TY - CONF A1 - Boro, I. A1 - Hinrichsen, G. A1 - Kalinka, Gerhard A1 - Hampe, Andreas A1 - Koßmehl, G. T1 - Zur Wechselstromleitfähigkeit von elektrisch leitfähgen Polymeren T2 - Präsentationsveranstaltung des Berliner Verbandes für Polymerforschung e.V. CY - Berlin, Germany DA - 1989-03-25 PY - 1989 AN - OPUS4-12126 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Was war die Schadensursache - was der Folgeschaden? T2 - polymertec 14 gemeinsam mit 14. Problemseminar "Deformation und Bruchverhalten von Kunststoffen", Hochschule Merseburg CY - Merseburg, Deutschland DA - 2014-06-25 PY - 2014 AN - OPUS4-32038 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hinrichs, V. A1 - Leistner, A. A1 - Kalinka, Gerhard A1 - Schulz, Eckhard A1 - Hinrichsen, G. T1 - Viscoelastic properties of the interphase in fibre reinforced polymers - measurement and simulation KW - Polymer KW - Glass fibre KW - Interphase KW - Coating KW - Glass transition KW - Dynamic KW - Viscoelastic PY - 1999 VL - 6 IS - 2 SP - 93 EP - 101 PB - North-Holland CY - New York, NY AN - OPUS4-12003 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Verbundwerkstoffe als Energiespeicher T2 - 4. Umwelt- und Technologietag, Fa. Brose CY - Coburg, Deutschland DA - 2014-09-25 PY - 2014 AN - OPUS4-32039 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schukar, Vivien A1 - Baitinger, Eugen A1 - Kusche, Nadine A1 - Steinke, F. A1 - Habel, Wolfgang T1 - Use of spectral conditions to separate strain and temperature effects in fibre Bragg grating sensors embedded in load-carrying anisotropic laminates N2 - This work presents a further development of the methods of simultaneous determination of temperature and axial strain using a single fibre Bragg grating (FBG). The reflected spectrum of composite-embedded FBG sensors has been analyzed in order to separate temperature and load effects. We found out that during the curing process of the laminates, a superstructure has been introduced on the FBG. Analyzing this effect, a temperature and strain separation was implemented by simply calculating and comparing the integrated intensity of the spectral response signal. A mathematical four-parametric model has been developed to calculate the reflected spectrum of a superstructured fibre Bragg grating. The mathematically achieved data has been evaluated with experimentally determined data from fibre Bragg gratings embedded in glass-fibre reinforced composite materials. KW - Fibre Bragg grating KW - Patch KW - Four-parametric KW - model KW - Superstructure KW - Temperature KW - Strain PY - 2013 U6 - https://doi.org/10.1007/s11340-013-9773-y SN - 0014-4851 SN - 1741-2765 VL - 54 IS - 3 SP - 421 EP - 429 PB - Springer CY - Norwell, Mass. AN - OPUS4-29452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Asadujjaman, Asad A1 - Ahmadi, Vahid A1 - Schönhals, Andreas A1 - ten Brummelhuis, N. T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from hydrogen-bonding monomers N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - UCT&IOCB Theoretical Chemistry Seminars CY - University of Chemistry and Technology, Department of Physical Chemistry, Prague, Czech Republic DA - 24.11.2017 KW - Thermoresponsive polymers KW - UCST polymers KW - 2,6-diaminopyridine PY - 2017 AN - OPUS4-43129 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Schönhals, Andreas A1 - ten Brummelhuis, N. A1 - Ahmadi, Vahid A1 - Asadujjaman, Asad T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from acrylamide-based monomers N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the right side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - Bioorganik 2017 – 26th Symposium "Bioorganic Chemistry" for young researchers CY - Berlin, Germany DA - 20.09.2017 KW - Thermoresponsive polymers KW - UCST polymers KW - 2,6-diaminopyridine KW - Acrylamide PY - 2017 AN - OPUS4-42007 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Asadujjaman, Asad A1 - Ahmadi, Vahid T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from monomers with hydrogen-bonding interactions N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and/or 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - Invited Talk (Prof. Christine Papadakis) Technische Universität München - Soft Matter Physics CY - Munich, Germany DA - 03.07.2018 KW - Thermoresponsive polymer KW - UCST-type polymer KW - H bonds KW - Diaminopyridine KW - Acrylamide PY - 2018 AN - OPUS4-45423 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Asadujjaman, Asad T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from hydrogen-bonding monomers N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - Invited talk (Dr. Jean-Francois Lutz) Institut Charles Sadron CY - Strasbourg, France DA - 26.01.2018 KW - Thermoresponsive polymer KW - UCST-type polymer KW - H bonds KW - Diaminopyridine KW - Acrylamide PY - 2018 AN - OPUS4-44001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Asadujjaman, Asad A1 - Ahmadi, Vahid T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from hydrogen-bonding monomers N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - Séminaire Laboratoire de Chimie des Polymères (LCP), UPMC, Paris CY - Paris, France DA - 28.09.2017 KW - UCST-type polymers KW - H-bonding monomers PY - 2017 AN - OPUS4-42478 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Kent, B. A1 - ten Brummelhuis, N. A1 - Schönhals, Andreas A1 - Asadujjaman, Asad T1 - Upper Critical Solution Temperature (UCST)-type thermoresponsive polymers from acrylamide-based monomers N2 - UCST-type thermoresponsive polymers that phase separate from solution upon cooling present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel UCST-type polymers because of their hydrophilic nature (with the right side chain) and propensity to form hydrogen bonds. We want to present our latest results on the copolymer poly(acrylamide-co-acrylonitrile) (P(AAm-co-AN)) that present a UCST in water as well as on two homopolymers based on an acrylamide derivative of 2,6-diaminopyridine, namely poly(N-(6-aminopyridin-2-yl)acrylamide) (PNAPAAm) and poly(N-(6-acetamidopyridin-2-yl)acrylamide) (PNAcAPAAm) that show UCST-type thermoresponsiveness in water/alcohol mixtures. Our focus for P(AAm-co-AN)) is its aggregation behaviour above and below its phase transition temperature as the size of thermoresponsive polymeric systems is of prime importance for biomedical applications (as size dependent processes take place in the body) and is linked to the optical properties of a material that matter in materials science. In the case of PNAPAAm and PNAcAPAAm, we focused on the co-solvency/co-non solvency effect on the phase transition temperature in water/alcohol mixture. Indeed, polymers with UCST behavior below 60°C in water/alcohol mixtures are extremely promising for the preparation of “smart” materials for sensing. T2 - Soft smart responsive materials workshop: Fundamentals and applications (SmartCECAM) CY - Mainz, Germany DA - 11.05.2017 KW - Thermoresponsive polymers KW - UCST-type polymers KW - poly(acrylamide-co-acrylonitrile) KW - 2,6-diaminopyridine-based polymers KW - co-solvency in water/acohol mixture PY - 2017 AN - OPUS4-40211 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Asadujjaman, Asad A1 - Ahmadi, Vahid T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from hydrogen-bonding monomers N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - Deutsche Physikalische Gesellschaft (DPG)-Frühjahrtagung 2018 CY - Berlin, Germany DA - 11.03.2018 KW - Thermoresponsive polymer KW - UCST-type polymer KW - H bonds KW - Diaminopyridine KW - Acrylamide PY - 2018 AN - OPUS4-44569 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle A1 - Asadujjaman, A. A1 - Ahmadi, V. T1 - Upper Critical Solution Temperature (UCST)-type Thermoresponsive Polymers from Hydrogen-Bonding Monomers N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications,but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or Ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and/or 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - Bordeaux Polymer Conference BPC 2018 CY - Bodeaux, France DA - 28.05.2018 KW - Acrylamide KW - Thermoresponsive polymer KW - UCST-type polymer KW - H-bonds KW - Diaminopyridine PY - 2018 AN - OPUS4-45155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Boro, I. A1 - Hinrichsen, G. A1 - Hampe, Andreas T1 - Untersuchungs des Ermüdungsverhaltens glasfaserverstärkter Thermoplaste mittels Schwingungsmessungen T2 - Zweites Werkstoffsymposium Neue Verbundwerkstoffe CY - Regensburg, Germany DA - 1990-10-05 PY - 1990 AN - OPUS4-12127 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Untersuchung des Faser-Matrix-Interface in Verbundwerkstoffen mit Einzelfaserversuchen T2 - Technische Universität Clausthal, Institut für Polymerwerkstoffe und Kunststofftechnik - Eingeladener Vortrag CY - Clausthal-Zellerfeld, Germany DA - 2006-04-26 PY - 2006 AN - OPUS4-13803 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Schulz, Eckhard A1 - Hampe, Andreas T1 - Untersuchung der Phasenhaftung in Verbundwerkstoffen mit dem Faser-Eindrückversuch T2 - Wissensbörse - Präparationstechnik und Analytik CY - Berlin, Germany DA - 19.02.1998 PY - 1998 AN - OPUS4-12104 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kalinka, Gerhard A1 - Hinrichsen, G. T1 - Two-dimensional computer simulation of spherulite formation by branching lamellae KW - Thermoplaste KW - Kristallisation KW - Sphärolithe KW - Lamellen KW - Modellrechnungen PY - 1997 SN - 0323-7648 SN - 1521-4044 VL - 48 SP - 256 EP - 261 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-12004 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hampe, Andreas A1 - Kalinka, Gerhard A1 - Marotzke, Christian T1 - The Single Fibre Pull-Out Test Performed with a Microcomposite Sample T2 - The Seventh International Conference on Composite Interfaces - ICCI-VII CY - Fujisawa, Kanagawa, Japan DA - 1998-05-10 PY - 1998 AN - OPUS4-5940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hampe, Andreas A1 - Kalinka, Gerhard A1 - Schulz, Eckhard T1 - The Fracture Process in the Interphase Investigated by the Single Fiber Pull-out Test T2 - Composites Testing and Standardisation ECCM-CTS 2 CY - Hamburg, Germany DA - 1994-09-13 PY - 1994 AN - OPUS4-12009 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hampe, Andreas A1 - Marotzke, Christian A1 - Brzezinka, Klaus-Werner A1 - Kalinka, Gerhard A1 - Schulz, Eckhard T1 - The Fracture Process in the Fibre/Matrix Interphase T2 - The Fifth International Conference on Composite Interfaces CY - Gothenburg, Sweden DA - 1994-07-20 PY - 1994 AN - OPUS4-5908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hinrichsen, G. A1 - Hinrichs, V. A1 - Kalinka, Gerhard A1 - Leistner, André A1 - Macht, Christian A1 - Schulz, Eckhard A1 - Yu, Erkang T1 - The Fiber/Matrix Interphase: New Insights into an old Problem T2 - INTERNATIONAL CONFERENCES ON POLYMER CHARACTERIZATION POLYCHAR-6 CY - Denton, TX, USA DA - 1998-01-07 PY - 1998 AN - OPUS4-12006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Plichta, T. A1 - Sirjovona, V. A1 - Zvonek, M. A1 - Kalinka, Gerhard A1 - Cech, V. T1 - The Adhesion of Plasma Nanocoatings Controls the Shear Properties of GF/Polyester Composite N2 - High-performance fibre-reinforced polymer composites are important construction materials based not only on the specific properties of the reinforcing fibres and the flexible polymer Matrix but also on the compatible properties of the composite interphase. First, oxygen-free (a-CSi:H) and oxygen-binding (a-CSiO:H) plasma nanocoatings of different mechanical and tribological properties were deposited on planar silicon dioxide substrates that closely mimic E-glass. The nanoscratch test was used to characterize the nanocoating adhesion expressed in terms of critical normal load and work of adhesion. Next, the same nanocoatings were deposited on E-glass fibres, which were used as reinforcements in the polyester composite to affect its interphase properties. The shear properties of the polymer composite were characterized by macro- and micromechanical tests, namely a short beam shear test to determine the short-beam strength and a single fibre push-out test to determine the interfacial shear strength. The results of the polymer composites showed a strong correlation between the short-beam strength and the interfacial shear strength, proving that both tests are sensitive to changes in fibre-matrix adhesion due to different surface modifications of glass fibres (GF). Finally, a strong correlation between the shear properties of the GF/polyester composite and the adhesion of the plasma nanocoating expressed through the work of adhesion was demonstrated. Thus, increasing the work of adhesion of plasma nanocoatings from 0.8 to 1.5 mJ·m−2 increased the short-beam strength from 23.1 to 45.2 MPa. The results confirmed that the work of adhesion is a more suitable parameter in characterising the level of nanocoating adhesion in comparison with the critical normal load. KW - Mechanical properties KW - Plasma nanocoatings KW - Glass fibre KW - Polymer composite KW - Short-beam strength KW - Interfacial shear strength KW - Work of adhesion PY - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-521844 VL - 13 IS - 4 SP - 593 PB - MDPI CY - Basel,Schweiz AN - OPUS4-52184 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Testing the interface shear strength of carbon fibre reinforced composites T2 - Polydays 2006 CY - Berlin, Germany DA - 2006-10-04 PY - 2006 AN - OPUS4-13804 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Testing the fibre-matrix adhesion in fiber reinforced polymers using the single fibre push-out method T2 - 8th European Conference on Applications of Surface and Interface Analysis (ECASIA 99) CY - Seville, Spain DA - 1999-10-04 PY - 1999 AN - OPUS4-12106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Testing the fibre matrix interface of short glass fibre reinforced PMCs with using the push out technique N2 - With this presentation, the push-out technique is explained. The focus of the experimental work is on the characterization of the fiber-matrix interface of short fiber reinforced composites. The reinforcing component was glass fibers and the matrix polymer was PA6.6 and PPA. It is demonstrated for the first time that the push-out technique ca be applied on injection molded short fiber PMC and is sensitive to the mechanical interface properties. Further studies are planned on the influence of multiple processing, the temperature and humidity. T2 - Composirtes United Workshop „Fiber Matrix Interphases“ CY - Online meeting DA - 09.11.2023 KW - Polymer Matrix Composite KW - Glass Fibres KW - PA6.6 KW - PPA KW - Push-out Test KW - Interface Strength PY - 2023 AN - OPUS4-59053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kalinka, Gerhard A1 - Sahin, M. A1 - Schlögl, S. A1 - Wang, J. A1 - Kaynak, B. A1 - Mühlbacher, I. A1 - Ziegler, W. A1 - Kern, W. A1 - Grützmacher, H. T1 - Tailoring the interfaces in glass fiber-reinforced photopolymer composites N2 - The present work provides a comparative study on the interface and adhesion properties of surface modified single glass fibers embedded in an acrylate matrix. To facilitate a covalent bonding at the fibermatrix interface, the fibers are functionalized with selected organosilanes that comprise either passive (unsaturated C¼C bonds of methacrylate moieties) or photoactive functionalities (photocleavable bis(acyl)phosphane oxide groups). Immobilization of the functional silanes is carried out by a classic silanization reaction involving a condensation reaction across the surface hydroxyl groups of the inorganic glass fibers. The change of the physico-chemical properties of the fibers due to desizing and subsequent surface modification is monitored by X-ray photoelectron spectroscopy and zeta potential measurements. In addition, scanning electron microscopy is used to follow the changes in surface morphology. After the modification step, the desized and modified single fibers are embedded in a photocurable acrylate resin formulation. By performing single fiber pull-out tests, maximum pull-out force, friction strength and apparent interfacial shear strength are determined as a function of the coupled silanes. The results reveal that the attached organosilanes lead to a significant increase in adhesion strength, whilst the performance of the photo-cleavable organosilane is superior to the passive methacryl-functional derivative. KW - Photocleavable organosilanes KW - Fiber-matrix interface KW - Photopolymer composites KW - Single fiber pull-out test KW - Surface modification PY - 2018 U6 - https://doi.org/10.1016/j.polymer.2018.03.020 SN - 0032-3861 VL - 141 SP - 221 EP - 231 PB - Elsevier Ltd. CY - New York AN - OPUS4-44784 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pommet, M. A1 - Juntaro, J. A1 - Heng, J.Y.Y. A1 - Mantalaris, A. A1 - Lee, A.F. A1 - Wilson, K. A1 - Kalinka, Gerhard A1 - Shaffer, M.S.P. A1 - Bismarck, A. T1 - Surface modification of natural fibers using bacteria: depositing bacterial cellulose onto natural fibers to create hierarchical fiber reinforced nanocomposites N2 - Triggered biodegradable composites made entirely from renewable resources are urgently sought after to improve material recyclability or be able to divert materials from waste streams. Many biobased polymers and natural fibers usually display poor interfacial adhesion when combined in a composite material. Here we propose a way to modify the surfaces of natural fibers by utilizing bacteria (Acetobacter xylinum) to deposit nanosized bacterial cellulose around natural fibers, which enhances their adhesion to renewable polymers. This paper describes the process of modifying large quantities of natural fibers with bacterial cellulose through their use as substrates for bacteria during fermentation. The modified fibers were characterized by scanning electron microscopy, single fiber tensile tests, X-ray photoelectron spectroscopy, and inverse gas chromatography to determine their surface and mechanical properties. The practical adhesion between the modified fibers and the renewable polymers cellulose acetate butyrate and poly(l-lactic acid) was quantified using the single fiber pullout test. KW - Composires KW - Bacteria KW - Surface KW - Cellulose natural fibers PY - 2008 U6 - https://doi.org/10.1021/bm800169g SN - 1525-7797 VL - 9 IS - 6 SP - 1643 EP - 1651 PB - ACS Publ. CY - Washington, DC, USA AN - OPUS4-23162 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shirshova, N. A1 - Bismarck, A. A1 - Carreyette, S. A1 - Fontana, Q.P.V. A1 - Greenhalgh, E.S. A1 - Jacobsson, P. A1 - Johansson, P. A1 - Marczewski, M.J. A1 - Kalinka, Gerhard A1 - Kucernak, A.R.J. A1 - Scheers, J. A1 - Shaffer, M.S.P. A1 - Steinke, J.H.G. A1 - Wienrich, Malte T1 - Structural supercapacitor electrolytes based on bicontinuous ionic liquid-epoxy resin systems N2 - 'Structural electrolytes' retain the desirable mechanical characteristics of structural (epoxy) resins whilst introducing sufficient ionic conductivity to operate as electrolytes in electrochemical devices. Here, a series of ionic liquid–epoxy resin composites were prepared to identify the optimum system microstructure required to achieve a high level of multifunctionality. The ionic conductivity, mechanical properties, thermal stability and morphology of the cured epoxy based structural electrolytes were studied as a function of phase composition for three fully formulated high performance structural epoxy systems. At only 30 wt% of structural resin and 70 wt% of ionic liquid based electrolyte, stiff monolithic plaques with thicknesses of 2–3 mm were obtained with a room temperature ionic conductivity of 0.8 mS cm-1 and a Young's modulus of 0.2 GPa. This promising performance can be attributed to a long characteristic length scale spinodal microstructure, suggesting routes to further optimisation in the future. KW - Epoxy KW - Ionic liquid KW - Supercapacitor PY - 2013 U6 - https://doi.org/10.1039/c3ta13163g SN - 2050-7496 SN - 2050-7488 VL - 1 IS - 48 SP - 15300 EP - 15309 PB - RSC CY - London [u.a.] AN - OPUS4-29735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilder, Constanze A1 - Schukar, Marcus A1 - Steffen, Milan A1 - Krebber, Katerina T1 - Structural health monitoring of composite structures by distributed fibre optic sensors N2 - Structural Health Monitoring of composite materials gains in importance with the increasing use of Composite structures for safety-related applications, e.g. in aerospace. Because of the material properties of composites, defects often occur inside the structures and raise the demand for integrated sensors. The advantages of optical fibres predestine them not only for the surface-application on composite structures but also for the Integration into composite structures. Even without quasi-distributed sensors such as FBGs or LPGs, the optical fibre itself can be used to measure the structure and occurring events over the entire fibre length by distributed sensing techniques. This paper presents the surface-application of polyimide coated silica optical fibres onto PEEK specimens and the integration of copper and polyimide coated silica optical fibres into an AS-4/PEEK Composite to be used as distributed fibre optic sensors for SHM. Results from distributed measurements by optical backscatter reflectometry based on Rayleigh backscattering are shown. T2 - 5th International symposium on NDT in aerospace CY - Singapore DA - 13.11.2013 KW - Structural health monitoring (SHM) KW - Composite structures KW - Optical fibre KW - Distributed fibre optic sensors KW - Optical backscatter reflectometry PY - 2013 SN - 1435-4934 SP - 1 EP - 7 AN - OPUS4-29687 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marotzke, Christian T1 - Strength of composite structural parts - role of the fiber/matrix interface N2 - The strength of laminates distinctly depends on the transverse strength of the laminas. The transverse failure is dominated by the adhesion between fiber and matrix. Usual strength criteria however do not take into account the adhesive strength explicitly. The determination of the interface strength is performed on the micromechanical scale using single fiber specimens. The fibers are loaded under off-axis loading while the debonding is monitored under a microscope. The stresses acting in the Interface are calculated by finite element analyses. It is found that for off-axial angles up to 35° interfacial debonding is the dominant failure mode while fiber breakage takes place at lower angles. The occurrence of fiber breakage and debonding under off-axis loading shows that the restriction to two potential failure planes - perpendicular or parallel to the fibers - as applied in common failure criteria has to be put in question. T2 - SEICO 11 - SAMPE Europe - 32nd International technical conference CY - Paris, France DA - 28.03.2011 KW - Composites KW - Strength KW - Adhesion PY - 2011 SN - 978-3-9523565-3-1 IS - Session 3B SP - 250 EP - 257 AN - OPUS4-23680 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Sonderprüfverfahren für Verbundwerkstoffe T2 - Vortragsveranstaltung VDI-AK Kunststofftechnik, BV BB an der TU Berlin CY - Berlin, Deutschland DA - 2011-03-17 PY - 2011 AN - OPUS4-34456 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Single Fiber Pull-out Test T2 - 4th International CFK-Valley Stade Convention CY - Stade, Germany DA - 2010-06-15 PY - 2010 AN - OPUS4-23289 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja A1 - Kalinka, Gerhard A1 - Schulz, Ulrich T1 - Simulation von Kratzeinwirkungen am Beispiel bewitterter Polymerwerkstoffe T2 - 32. Jahrestagung der GUS (Gesellschaft für Umweltsimulation) CY - Pfinztal, Germany DA - 2003-03-26 PY - 2003 AN - OPUS4-4032 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barnefske, Lena A1 - Wachtendorf, Volker T1 - Self-healing silicone rubber for fluorescent partial discharge POF sensors in high-voltage cable accessories N2 - To avoid a catastrophic failure of insulation in high-voltage (HV) applications, a monitoring of partial discharges (PDs) is necessary. Fluorescently labelled polymer optical fibers (F-POF) offer an electrically passive method for PD detection in HV facilities. F-POFs could be embedded in HV cable accessories, which are usually made of silicone rubber. Herein they detect the light emitted by the PD and convert it into an electrical signal that can be monitored. Due to the difficult accessibility of HV cable accessories, a self-healing silicone rubber with prolonged service life after PD detection represents an attractive material design for HV accessories. With this contribution, we would like to present and discuss the possibilities of combining self-healing materials with POF-based sensors for PD detection in HV applications. T2 - 26th International Conference on Plastic Optical Fibres CY - Aveiro, Portugal DA - 13.09.2017 KW - Fluorescent polymer optical fibres KW - Partial discharge detection KW - High voltage cable accessories KW - Self-healing KW - Silicone rubber PY - 2017 SN - 978-989-97345-2-4 SP - paper 16, 1 EP - 5 AN - OPUS4-42510 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barnefske, Lena A1 - Wachtendorf, Volker T1 - Self-healing silicone rubber for F-POF partial discharge sensors in HV cable accessories N2 - To avoid a catastrophic failure of insulation in high-voltage (HV) applications, a monitoring of partial discharges (PD) is necessary. Fluorescently labelled polymer optical fibres (F-POF) offer an electrically passive method for PD detection in HV facilities. F-POF could be embedded into HV cable insulation material, which are usually made of silicone rubber. Due to the difficult accessibility of HV cable accessories, a self-healing silicone rubber, based on incorporated capsules, with prolonged service life after PD detection represents an attractive material design for HV electrical insulation. T2 - 26th International Conference on Plastic Optical Fibres CY - Aveiro, Portugal DA - 13.09.2017 KW - Fluorescent polymer optical fibres KW - Partial discharge detection KW - High voltage cable accessories KW - Self-healing KW - Silicone rubber PY - 2017 AN - OPUS4-42511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krauklis, A. E. A1 - Starovka, O. A1 - Gibhardt, D. A1 - Aouissi, H. A. A1 - Burlakovs, J. A1 - Sabalina, A. A1 - Fiedler, Bodo A1 - Kalinka, Gerhard T1 - Reversible and irreversible effects on the epoxy GFRP fiber-matrix interphase due to hydrothermal aging N2 - Epoxy R-Glass Fiber-Reinforced Polymer (GFRP) composite plates were hydrothermally aged at 60 ◦C for 23, 75, and 133 days. The water content reached 0.97 wt%, 1.45 wt% and 1.63 wt%, respectively. The studied GFRP matrix was inert to hydrolysis or chain scission, allowing for investigation of irreversible changes in the fiber-matrix interphase due to hydrothermal aging upon re-drying. During each period, a subset of the specimens was removed from the water bath and dried in a chamber. The weight loss upon drying was explained with epoxy leaching (impurities), sizing-rich interphase hydrolysis, glass fiber surface hydrolysis, accumulated degradation products escaping, and water changing state from bound to free. The influence of hydrothermal aging on the fiber-matrix interfacial properties was investigated. Lower interfacial strength of hydrothermally aged (wet) samples was attributed to plasticization of the epoxy, plasticization and degradation of the sizing-rich interphase (including formation of hydrolytic flaws), and hydrolytic degradation of the glass fiber surface. The kinetics of epoxy-compatible epoxysilane W2020 sizing-rich interphase hydrolysis provided an estimate of ca. 1.49%, 4.80%, and 8.49% of the total composite interphase degraded after 23, 75, and 133 days, respectively. At these conditions, the interface lost 39%, 48%, and 51% of its strength. Upon re-drying the specimens, a significant part of the interfacial strength was regained. Furthermore, an upward trend was observed, being 13%, 10% and 3% strength, respectively; thus, indicating a possibility of partial recovery of properties. KW - GFRP KW - Hydrothermal Ageging KW - Interphase KW - Water Diffusion KW - Desorption KW - Interfacial Strength PY - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-581554 SN - 2666-6820 VL - 12 SP - 1 EP - 9 PB - Elsevier B.V. CY - Amsterdam, Niederlande AN - OPUS4-58155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gebhardt, M. A1 - Manolakis, I. A1 - Chatterjee, A. A1 - Kalinka, Gerhard A1 - Deubener, J. A1 - Pfnür, H. A1 - Chakraborty, S. A1 - Meiners, D. T1 - Reducing the raw material usage for room temperature infusible and polymerisable thermoplastic CFRPs through reuse of recycled waste matrix material N2 - In this work, a closed loop recycling process is investigated, which allows polymerised bulk thermoplastic matrix (Elium 150) from production waste (also referred to as recyclate) to be reused as additive in composite manufacturing by vacuum assisted resin infusion (VARI) of virgin Elium 150 monomer. It is shown that this process can save up to 7.5 wt% of virgin material usage in each processing cycle. At the same time, the thermal stability and stiffness of the composite increases with the proportion of recyclate introduced. Contemporarily, the shear and bending properties have also been observed to improve. Gel permeation chromatography (GPC) showed that the changes observed are due to an increase in molecular weight with the recyclate content. In particular, a correlation between the molecular weight and the shear properties of the composite was discovered using single fibre push-out tests. KW - Mechanical properties KW - Recycling KW - Carbon fibres KW - Fibre/matrix bond PY - 2021 U6 - https://doi.org/10.1016/j.compositesb.2021.108877 SN - 1359-8368 VL - 216 SP - 108877 PB - Elsevier Ltd. CY - Niederlande AN - OPUS4-52711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gebhardt, M. A1 - Malolakis, I. A1 - Kalinka, Gerhard A1 - Deubener, J. A1 - Chakraborty, S. A1 - Meiners, D. T1 - Re-use potential of carbon fibre fabric recovered from infusible thermoplastic CFRPs in 2nd generation thermosetting-matrix composites N2 - The research presented here attempts to assess the potential for re-using carbon fibre (CF) fabrics recovered from recycling infusible acrylic thermoplastic carbon fibre reinforced polymer composites (CFRPs) in a universal manner, i.e. by combining with a wide variety of matrices to manufacture 2nd generation composite laminates by resin infusion. The 2nd generation composites have been compared in terms of bulk and interfacial properties against counteparts processed with virgin carbon fibre fabric infused with the same matrices. Generally, an increase in damping (tanδ) was observed in all 2nd generation composites, which can be attributed to a residual thin thermoplastic layer present on the recovered fibres. The interfacial adhesion of the 2nd generation Composites was investigated by shear tests and scanning electron micsoscopy, and also appears to be less influenced by the type of matrix. KW - Composite recycling KW - Thermoplastic matrix KW - Thermosetting resin KW - Fibre/matrix bonding PY - 2021 U6 - https://doi.org/10.1016/j.coco.2021.100974 VL - 28 SP - 100974 PB - Elsevier Ltd. CY - Niederlande AN - OPUS4-53639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schulz, Eckhard A1 - Kalinka, Gerhard A1 - Meretz, S. A1 - Hampe, Andreas T1 - Pull-out of Single Fibres KW - Verstärkungsfaser KW - Verbundwerkstoffe KW - Interface KW - Adhäsion KW - Reibung KW - Haftung KW - Thermoplast PY - 1994 SN - 0945-0084 VL - 84 IS - 5 SP - 25 EP - 26 PB - Hanser CY - München AN - OPUS4-11989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sigrüner, M. A1 - Hüsken, Götz A1 - Pirskawetz, Stephan A1 - Herz, J. A1 - Muscat, D. A1 - Strübbe, N. T1 - Pull-out behavior of polymer fibers in concrete N2 - The bond between polymer fibers and the surrounding cementitious matrix is essential for the development of concrete reinforcement. The single fiber pull-out test (SFPT) is the standard characterization technique for testing the bond strength. However, the different phases of debonding cannot be distinguished by the SFPT. This study investigates the debonding of different polymer fibers from the surrounding cementitious matrix with a modified SFPT and proposes methods to change the SFPT setup to generate more valuable information on the debonding mechanism. The SFPT was equipped with linear variable differential transformers (LVDT), digital image correlation (DIC) and acoustic emission (AE) analysis. The results demonstrate that the modified SFPT allows a better understanding of the different phases of debonding during fiber pull-out. Furthermore, bond strength values calculated by different methods reveal that the chemical bond of the investigated polymers is not different as reported by previous studies. Deformation measurements performed using LVDTs and DIC are suitable measuring techniques to characterize the debonding mechanism in SFPT. A correlation between recorded AE and debonding phases was not found. KW - Polymer Fibres KW - Concrete KW - Pull-Out Behaviour KW - Debonding Mechanism PY - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-582918 SN - 2642-4169 SP - 1 EP - 13 PB - Wiley Periodicals, LLC. AN - OPUS4-58291 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Prüfung der Faser-Matrix-Wechselwirkung in Kompositen mittels Einzelfaser push- und pull-out Methoden T2 - 4. Wildauer Duromer-Tagung, TH Wildau CY - Wildau, Deutschland DA - 2014-03-03 PY - 2014 AN - OPUS4-32036 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Blaker, J. J. A1 - Anthony, David B. A1 - Tang, G. A1 - Shamsuddin, S.-R. A1 - Kalinka, Gerhard A1 - Wienrich, Malte A1 - Abdolvand, Amin A1 - Shaffer, M. S. P. A1 - Bismarck, A. T1 - Property and shape modulation of carbon fibers using lasers N2 - An exciting challenge is to create unduloid-reinforcing fibers with tailored dimensions to produce synthetic composites with improved toughness and increased ductility. Continuous carbon fibers, the state-of-the-art reinforcement for structural composites, were modified via controlled laser irradiation to result in expanded outwardly tapered regions, as well as fibers with Q-tip (cotton-bud) end shapes. A pulsed laser treatment was used to introduce damage at the single carbon fiber level, creating expanded regions at predetermined points along the lengths of continuous carbon fibers, while maintaining much of their stiffness. The range of produced shapes was quantified and correlated to single fiber tensile properties. Mapped Raman spectroscopy was used to elucidate the local compositional and structural changes. Irradiation conditions were adjusted to create a swollen weakened region, such that fiber failure occurred in the laser treated Region producing two fiber ends with outwardly tapered ends. Loading the tapered fibers allows for viscoelastic energy dissipation during fiber pull-out by enhanced friction as the fibers plough through a matrix. In these tapered fibers, diameters were locally increased up to 53%, forming outward taper angles of up to 1.8°. The tensile strength and strain to failure of the modified fibers were significantly reduced, by 75% and 55%, respectively, ensuring localization of the break in the expanded region; however, the fiber stiffness was only reduced by 17%. Using harsher irradiation conditions, carbon fibers were completely cut, resulting in cottonbud fiber end shapes. Single fiber pull-out tests performed using these fibers revealed a 6.75-fold increase in work of pull-out compared to pristine carbon fibers. Controlled laser irradiation is a route to modify the shape of continuous carbon fibers along their lengths, as well as to cut them into controlled lengths leaving tapered or cotton-bud shapes. KW - Composite KW - Irradiation KW - Pull-out tests KW - Pulsed laser treatment KW - Single carbon fibers PY - 2016 U6 - https://doi.org/10.1021/acsami.6b05228 SN - 1944-8244 SN - 1944-8252 VL - 8 IS - 25 SP - 16351 EP - 16358 PB - ACS Publications CY - 1155 Sixteenth Street, NW, Washington, DC 20036, USA AN - OPUS4-37699 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Radl, S. A1 - Kreimer, M. A1 - Manhart, J. A1 - Griesser, T. A1 - Moser, A. A1 - Pinter, G. A1 - Kalinka, Gerhard A1 - Kern, W. A1 - Schlögl, S. T1 - Photocleavable epoxy based materials N2 - The present study aims at the development of photodegradable epoxy based materials comprising o-nitrobenzyl ester links that undergo well defined bond cleavage in response to UV irradiation. New bi-functional epoxy based monomers bearing o-nitrobenzyl ester groups are synthesized and thermally cured with an anhydride hardener to yield photosensitive polymers and duromers. The UV induced changes in solubility are exploited for the preparation of positive-type photoresists. Thin patterned films are obtained by photolithographic processes and characterized by microscopic techniques. The results evidence that sensitive resist materials with good resolution and high contrast behavior can be accomplished. Along with resist technology, the applicability of o-nitrobenzyl chemistry in the design of recyclable polymer materials with thicknesses in the millimeter range is evaluated. By monitoring the thermo-mechanical properties upon UV illumination, a distinctive depletion of storage modulus and glass transition temperature is observed with increasing exposure dose. Additionally, single fiber pull-out tests are carried out revealing a significant decrease of the interfacial adhesion at the fiber-matrix interface due to the phototriggered cleavage reaction. KW - Epoxy based network KW - Photocleavage KW - o-Nitrobenzyl ester KW - Adhesion KW - Mechanical properties KW - Interfacial shear strength PY - 2015 U6 - https://doi.org/10.1016/j.polymer.2015.05.055 SN - 0032-3861 SN - 1873-2291 VL - 69 SP - 159 EP - 168 PB - Elsevier Ltd. AN - OPUS4-34566 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Optische Beobachtungen der Faser-Matrix-Trennung im Pull-out-Versuch N2 - Der Vortrag behandelt Rissentstehung und Ausbreitung an Faser-Matrix-Interfaces, untersucht mit dem optischen Mikroskop. T2 - Composites United, CU-Arbeitsgruppe/n Faser-Matrix-Haftung & Matrices CY - Online meeting DA - 02.12.2021 KW - Faser KW - Matrix KW - Pull-out KW - Interface PY - 2021 AN - OPUS4-53968 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Munz, Martin A1 - Sturm, Heinz A1 - Kalinka, Gerhard T1 - On the stiffness gradient at the interface between an amine-cured epoxy and a thermoplast T2 - 6. Workshop 'Rasterkraftmikroskopie in der Werkstoffwissenschaft' an der Uni Erlangen, Inst. für Werkstoffwissenschaften veranstaltet vom Arbeitskreis 'Rastersondenmikroskopie in der Werkstoffwissenschaft' im Fachausschuss Metallographie der Deutschen Gesellschaft für Materialkunde (DGM) CY - Erlangen, Germany DA - 2005-02-17 PY - 2005 AN - OPUS4-7137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Chung, Jaeun T1 - Nanoscale Characterization of Epoxy Interphase on Copper Microstructures N2 - The epoxy/metal interface regions are recognized as crucial for the mechanical reliability of composite materials. In particular, the spatial stress distribution is governed by modulus variations, which may result from the physical-chemical interactions between epoxy and the metal surface. The properties of the interphase between bulk polymer and metal were analyzed in nanometer scale. It was aimed to characterize the stiffness gradient of the polymeric interphase, which was formed by a thermoset being cured in contact with a metal surface. N2 - Die Grenzfläche zwischen Epoxid und Metall spielt für die mechanische Zuverlässigkeit des Verbundwerkstoffes (Composite) Epoxid/Metall eine wichtige Rolle. Insbesondere hängt die räumliche Verteilung mechanischer Spannungen von Variationen des Elastizitätsmoduls ab, die durch die physikalisch-chemischen Wechselwirkungen zwischen dem Epoxid und der Metalloberfläche hervorgerufen werden können. Daher wurden die Eigenschaften des Grenzbereichs (Interphase) zwischen dem Polymer, das nicht durch Grenzflächen-Wechselwirkungen beeinflusst wurde (Bulk-Polymer), und dem Metall auf der Nanometer-Skala analysiert. Hauptziel war es, die Steifigkeitsgradienten innerhalb der Epoxid-Interphase zu detektieren. Diese können durch die Gegenwart der Metall-Grenzfläche (Interface) hervorgerufen werden, die einen Einfluss auf den Prozess der Aushärtung zeigt. Die Rasterkraftmikroskopie (Scanning Force Microscopy, SFM) im Force Modulation Mode (FMM) erlaubt die hochauflösende Abbildung von Steifigkeitsvariationen. Die Ergebnisse aus der SFM-FMM wurden mit Konzentrationsprofilen aus der energiedispersiven Analyse von Röntgenstrahlen im Rasterelektronenmikroskop (REM-EDX) verglichen, als auch mit Relaxationskurven aus der dynamisch-mechanischen Analyse (DMA), die an Epoxid-Referenzproben durchgeführt wurde. Die untersuchten Verbundwerkstoff-Proben bestanden aus Epoxid und Kupfer. Es wurde Elektronstrahl-Lithographie (EBL) in Verbindung mit der Lift-off Technik verwendet, um Kupfer-Mikroelektroden auf einem Silizium-Wafer herzustellen. Danach wurde die Mischung aus Epoxidharz und Amin-Härter in der Gegenwart der Kupfer-Mikroelektroden ausgehärtet, wodurch ein Epoxid/Kupfer Verbundwerkstoff entstand. Es wurden zwei verschiedene Epoxid-Härter Systeme verwendet, um unterschiedliche Probentypen herzustellen. Eines bestand aus Diglycidyl-Ether des Bisphenol A (DGEBA) und einem modifizierten cycloaliphatischen Amin (EPIKOTE828 und EPIKURE F205 von Resolution Europe). Das andere bestand aus DGEBA und einem aromatischen Amin (DER332 von Dow Chemical und DDS von Fluka Chemikalien). SFM-FMM erlaubt es, die lokalen mechanischen Eigenschaften des Grenzbereichs zu beschreiben. Die neue Art der Probenpräparation ermöglicht es, eine an die Erfordernisse der SFM-FMM angepasste Glattheit der zu untersuchenden Oberfläche zu erzielen. Bei der SFM-FMM wird die vertikale Position der Probe moduliert und die dynamische Verbiegungsamplitude des SFM-Cantilevers gemessen, während sich die Spitze im Kontakt mit der Probenoberfläche befindet. Neben dem resultierenden Amplituden- und Phasensignal sind noch andere Kontraste verfügbar, wie Topographie, Auflagekraft und Lateralkraft. Diese ergänzenden Kontraste wurden dazu verwendet, die Kupfer-Grenzfläche zu identifizieren. Ferner dienten sie der Kontrolle der Qualität der SFMMessung. Insbesondere konnte gezeigt werden, dass von der Topographie induzierte Kontraste auftreten können, wenn ihre Neigung mehr als ~|3°| beträgt. Außerdem wurde die Morphologie der Oberfläche des Epoxids untersucht, die noppenartige Strukturen, so genannte „Noduln“, aufwies. Bei den gegebenen Aushärtungsbedingungen (Tg bei 80°C über 2 Stunden, Nachhärtung bei 130°C über 1 Stunde) betrug die Durchschnittsgröße der Noduln ~125 nm, und 90 Prozent der Noduln waren zwischen 75 und 200 nm groß. Das aus EPIKOTE828-EPIKURE F205 bestehende Epoxid-System bildete eine Interphase mit einer Breite von ~1,9 μm aus und der Punkt der niedrigsten Steifigkeit war in einem Abstand von ~0,4 μm vom Kupfer. Andererseits wies das DER332-DDS System eine Interphase mit einer Breite von ~2,3–4,0 μm auf. Es wurden verschiedenartige Steifigkeitsprofile festgestellt. Diese Ergebnisse zeigen, dass die Eigenschaften des metallinduzierten Grenzbereichs vom Epoxid-System abhängen. Die Steifigkeit in der Nähe von Kupfer (bis zu 0,2–0,25 μm Abstand) war deutlich höher als im Volumen des Epoxids. Sowohl die im REM als auch die im TEM durchgeführten EDX-Messungen zeigten, dass die Konzentration des Amins in der Nähe von Kupfer verringert ist. Die unter Verwendung von SFM-FMM gemessene Steifigkeit wurde mit dem Modulwert verglichen, der mittels DMA an Referenzproben wohldefinierter Amin-Epoxid Konzentrationsverhältnisse bestimmt wurde. Die gefundene Relation wurde im Rahmen eines Reaktions-Diffusions Modells interpretiert. Danach treten räumliche Schwankungen im Konzentrationsverhältnis von Amin und Epoxid auf, die zu Variationen in der Netzwerkstruktur des ausgehärteten Epoxidsführen und sich somit auch auf dessen mechanische Eigenschaften auswirken. T3 - BAM Dissertationsreihe - 15 KW - Nanoscale Characterization KW - Epoxy Interphase KW - Copper Microstructures PY - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-1435 SN - 978-3-86509-514-3 SN - 1613-4249 VL - 15 SP - 1 EP - 104 PB - Wirtschaftsverlag NW CY - Bremerhaven AN - OPUS4-143 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schäferling, Michael T1 - Nanoparticle-based luminescent probes for intracellular sensing and imaging of pH N2 - Fluorescence imaging microscopy is an essential tool in biomedical research. Meanwhile, various fluorescent probes are available for the staining of cells, cell membranes, and organelles. Though, to monitor intracellular processes and dysfunctions, probes that respond to ubiquitous chemical parameters determining the cellular function such as pH, pO2, and Ca2+ are required. This review is focused on the progress in the design, fabrication, and application of photoluminescent nanoprobes for sensing and imaging of pH in living cells. The advantages of using nanoprobes carrying fluorescent pHindicators compared to single molecule probes are discussed as well as their limitations due to the mostly lysosomal uptake by cells. Particular attention is paid to ratiometric dual wavelength nanosensors that enable intrinsic referenced measurements. Referencing and proper calibration procedures are basic prerequisites to carry out reliable quantitative pH determinations in complex samples such as living cells. A variety of examples will be presented that highlight the diverseness of nanocarrier materials (polymers, micelles, silica, quantum dots, carbon dots, gold, photon upconversion nanocrystals, or bacteriophages), fluorescent pH indicators for the weak acidic range, and referenced sensing mechanisms, that have been applied intracellularly up to now. KW - pH sensing KW - Luminescent probes KW - Imaging PY - 2016 U6 - https://doi.org/10.1002/wnan.1366 SN - 1939-0041 SN - 1939-5116 VL - 8 IS - 3 SP - 378 EP - 413 PB - Wiley-Blackwell CY - Hoboken, New Jersey, USA AN - OPUS4-36367 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Elabshihy, Karim T1 - Nano-mechanical characterization of epoxy/Cu interphase N2 - Characterization of the mechanical properties of interphases is essential when designing multicomponent materials such as fiber-reinforced matrices, protective coatings or multi-layered structures for integrated circuits. It can provide vital information about the durability of the finished product as a composite because failure is often initiated in the interfacial region induced by internal or external stress during fabrication or service. Nanoindentation is a powerful tool for investigating mechanical properties on the micro/nano scale. However, there are some challenges associated with conducting nanoindentation near interface regions. One main challenge is that the small thickness of the interphase region (typically 1-2µm) makes it difficult to apply several adjacent indents without overlap. Another issue is that the indentations are usually restricted by local reinforcement, and it becomes difficult to isolate the change in mechanical properties due solely to interphase formation. In this study we try to gauge the feasibility of nanoindentation for characterizing epoxy/Cu interphases. We develop a sample preparation method and optimize nanoindentation parameters in an attempt to avoid the restrictions mentioned above. Atomic force microscopy (AFM) and finite element analysis are employed as reference techniques to evaluate the effectiveness of our technique. We show the influence of preparation method and nanoindentaion parameters on measurements of interphase properties and how they relate the mentioned challenges. T2 - Nanobrücken 2016 CY - Saarbrücken, Germany DA - 02.03.2016 KW - Composite KW - Epoxy KW - Interphase KW - Nanoindentation PY - 2016 AN - OPUS4-35496 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kaiser, T. M. A1 - Braune, C. A1 - Kalinka, Gerhard A1 - Schulz-Kornas, E. T1 - Nano-indentation of native phytoliths and dental tissues: implications for herbivore-plant combat and dental wear proxies N2 - Tooth wear induced by abrasive particles is a key process affecting dental function and life expectancy in mammals. Abrasive particles may be plant endogenous opal phytoliths, exogene wind-blown quartz dust or rain borne mineral particles ingested by mammals. Nano-indentation hardness of abrasive particles and dental tissues is a significant yet not fully established parameter of this tribological system. We provide consistent nano-indentation hardness data for some of the major antagonists in the dental tribosystem (tooth enamel, tooth dentine and opaline phytoliths from silica controlled cultivation). All indentation data were gathered from native tissues under stable and controlled conditions and thus maximize comparability to natural systems. Here we show that native (hydrated) wild boar enamel exceeds any hardness measures known for dry herbivore tooth enamel by at least 3 GPa. The native tooth enamel is not necessarily softer then environmental quartz grit, although there is little overlap. The native hardness of the tooth enamel exceeds that of any silica phytolith hardness recently published. Further, we find that native reed phytoliths equal native suine dentine in hardness, but does not exceed native suine enamel. We also find that native suine enamel is significantly harder than dry enamel and dry phytoliths are harder than native phytoliths. Our data challenge the claim that the culprit of tooth wear may be the food we chew, but suggest instead that wear may relates more to exogenous than endogenous abrasives. KW - Phytolith KW - Indentation hardness KW - Enamel KW - Dentine KW - Tooth wear PY - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-451417 UR - http://zoobank.org/5C7DBB2B-B27D-4CE6-9656-33C4A0DA0F39 VL - 2 SP - 55 EP - 63 PB - PENSOFT CY - USA AN - OPUS4-45141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bismarck, A. A1 - Carreyette, S. A1 - Fontana, Q.P.V. A1 - Greenhalgh, E.S. A1 - Jacobsson, P. A1 - Johansson, P. A1 - Marczewski, M.J. A1 - Kalinka, Gerhard A1 - Kucernak, A. A1 - Shaffer, M.S. A1 - Shirshova, N. A1 - Steinke, J.H.G. A1 - Wienrich, Malte T1 - Multifunctional epoxy resin for structural supercapacitors N2 - Polymer-based electrolytes based on commercially available epoxy resins were prepared through the addition of a liquid electrolyte, a solution of a lithium salt in an ionic liquid. The polymer monoliths were characterized using impedance spectroscopy, 3-point bending test, scanning electron microscopy (SEM) and nitrogen adsorption (BET). The balance of ionic conductivity and flexural modulus is crucially dependent on the relative proportions of epoxy resin to electrolyte. Also the effect of the liquid electrolyte on curing kinetics and processing was assessed by complex viscosity measurements and differential scanning calorimetry (DSC). Only one out of the three resins investigated exhibited a significant acceleration effect. T2 - ECCM15 - 15th European conference on composite materials CY - Venice, Italy DA - 2012-06-24 KW - Multifunctional epoxy KW - Polymer electrolyte KW - Morphology KW - Ionic liquid PY - 2012 SN - 978-88-88785-33-2 SP - 1 EP - 8(?) AN - OPUS4-28694 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bismarck, A. A1 - Carreyette, Shuijin A1 - Fontana, Quentin P. A1 - Greenhalgh, E. A1 - Jacobsson, P. A1 - Johansson, P. A1 - Kalinka, Gerhard A1 - Wienrich, Malte T1 - Multifunctional Epoxy Resin for Structural Supercapacitors T2 - European Conference on Composite Materials 15 CY - Venice, Italy DA - 2012-06-24 PY - 2012 AN - OPUS4-27466 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Schulz, Eckhard T1 - Monitoring the interface crack propagation with micromechanical test devices T2 - Interfacial Phenomena in Composite Materials CY - Berlin, Germany DA - 2001-01-28 PY - 2001 AN - OPUS4-12107 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shirshova, Natasha A1 - Kalinka, Gerhard A1 - Bismarck, A. A1 - Carreyette, Shuijin A1 - Fontana, Quentin P. A1 - Greenhalgh, E. A1 - Kucernack, Anthony A1 - Schaffer, Milo A1 - Wienrich, Malte T1 - Modified epoxy resin as electrolytes for structural supercapacitors T2 - European Polymer Congress 2011 CY - Granada, Spain DA - 2011-06-26 PY - 2011 AN - OPUS4-24452 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Neumann, Burt T1 - Mikromechanische Testmethoden zur Bestimmung von Haftung und Reibung in Faserverbundwerkstoffen T2 - Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Institut für Strukturmechanik CY - Braunschweig, Germany DA - 2004-02-04 PY - 2004 AN - OPUS4-4700 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Mikromechanische Methoden zur Messung der Faser-Matrix-Haftung in Polymermatrix-Verbundwerkstoffen T2 - Kolloquium des Fraunhofer IZM CY - Teltow, Germany DA - 2007-07-20 PY - 2007 AN - OPUS4-15858 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Mikromechanik T2 - BAM, DGM Fachausschuss "Gefüge und Eigenschaften von Polymerwerkstoffen" CY - Berlin, Germany DA - 2003-12-05 PY - 2003 AN - OPUS4-4088 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marotzke, Christian A1 - Kalinka, Gerhard T1 - Microscopical failure processes in fiber reinforced polymers - Mechanical aspects of the adhesion between fiber and matrix T2 - 11th International Conference on Mechanics and Technology of Composite Materials CY - Sofia, Bulgaria DA - 2006-10-02 PY - 2006 AN - OPUS4-13239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marotzke, Christian A1 - Kalinka, Gerhard ED - Zachariev, G. T1 - Microscopical Failure Processes in Fiber Reinforced Polymers - Mechanical Aspects of the Adhesion between Fiber and Matrix T2 - 11th International Conference on Mechanics and Technology of Composite Materials CY - Sofia, Bulgaria DA - 2006-10-02 KW - Composite materials KW - Failure process KW - Adhesion PY - 2006 SP - 37 EP - 42 PB - Bulgarian Academy of Sciences CY - Sofia AN - OPUS4-14027 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Guerra, E. S. S. A1 - Silva, B. L. A1 - Melo, J. D. D. A1 - Kalinka, Gerhard A1 - Barbosa, A. P. C. T1 - Microscale evaluation of epoxy matrix composites containing thermoplastic healing agent N2 - Among the strategies to produce healable thermosetting systems is their modification by the addition of thermoplastic particles. This work investigates the influence of poly(ethylene-co-methacrylic acid) (EMAA) on fibermatrix interfacial properties of a glass fiber reinforced epoxy matrix composite. Epoxy-EMAA interactions were evaluated using differential scanning calorimetry (DSC) and infrared spectroscopy. The effects of EMAA on the epoxy network formation were evidenced by changes in glass transition temperature, cure kinetics and alteration of chemical groups during cure. Interfacial shear strength (IFSS) measurements obtained by single fiber pull-out tests indicate similar interfacial properties for pure and EMAA modified epoxy. Additionally, the potential for self-healing ability of an EMAA modified epoxy was demonstrated. However, IFSS after a healing cycle for the EMAA modified epoxy was lower as compared to the pure epoxy, because of the lower fiber-EMAA interfacial shear strength. So, thermoplastic healing agents has not only to fill cracks in the matrix material, but also have to be optimized regarding its interface properties to the reinforcing fibers. KW - Interfacial strength KW - Fiber/matrix bond KW - Self-healing KW - Polymer-matrix composites (PMC) PY - 2022 U6 - https://doi.org/10.1016/j.compscitech.2022.109843 SN - 0266-3538 VL - 232 SP - 1 EP - 9 PB - Elsevier Ltd. CY - Niederlande AN - OPUS4-56379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Micro indentation near stiff-soft phase boundaries T2 - Polydays 2004 CY - Potsdam, Germany DA - 2004-10-04 PY - 2004 AN - OPUS4-4703 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Micro indentation near stiff-soft boundaries T2 - "Nanomech5, 5th European Symposium on nano-Mechanical Testing" CY - Hückelhoven, Germany DA - 2004-09-07 PY - 2004 AN - OPUS4-4704 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Micro indentation and scratch tests for surface characterisation T2 - XXII. Donauländergespräche über die natürliche und künstliche Alterung von Polymeren CY - Berlin, Germany DA - 2001-09-17 PY - 2001 AN - OPUS4-7506 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hampe, Andreas A1 - Marotzke, Christian A1 - Kalinka, Gerhard T1 - Mechanische Messungen der Bruchzähigkeit des Faser-Matrix-Grenzbereiches in polymeren Verbundwerkstoffen T2 - 35. Internationale Chemiefaser-Tagung CY - Dornbirn, Austria DA - 1996-09-25 PY - 1996 AN - OPUS4-5922 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Marotzke, Christian T1 - Mechanische Eigenschaften des Faser/Matrix Interfaces in Verbundwerkstoffen T2 - ILA 2010-Berlin Airshow, Konferenz: Composites in der Luft- und Raumfahrt CY - Berlin, Germany DA - 2010-06-08 PY - 2010 AN - OPUS4-21415 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Mechanische Charakterisierung des Faser-Matrix-Interface mit Einzelfaser-Tests T2 - Werkstoffwoche 2004: Kongress für innovative Werkstoffe, Verfahren und Anwendungen CY - Munich, Germany DA - 2004-09-21 PY - 2004 AN - OPUS4-4701 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Greenhalgh, E.S. A1 - Ankersen, J. A1 - Asp, L. E. A1 - Bismarck, A. A1 - Fontana, Q.P.V. A1 - Houlle, M. A1 - Kalinka, Gerhard A1 - Kucernak, A. A1 - Mistry, M. A1 - Nguyen, S. A1 - Qian, H. A1 - Shaffer, M.S.P. A1 - Shirshova, N. A1 - Steinke, J.H.G. A1 - Wienrich, Malte T1 - Mechanical, electrical and microstructural characterisation of multifunctional structural power composites N2 - Multifunctional composites which can fulfil more than one role within a system have attracted considerable interest. This work focusses on structural supercapacitors which simultaneously carry mechanical load whilst storing/delivering electrical energy. Critical mechanical properties (in-plane shear and in-plane compression performance) of two monofunctional and four multifunctional materials were characterised, which gave an insight into the relationships between these properties, the microstructures and fracture processes. The reinforcements included baseline T300 fabric, which was then either grafted or sized with carbon nanotubes, whilst the baseline matrix was MTM57, which was blended with ionic liquid and lithium salt (two concentrations) to imbue multifunctionality. The resulting composites exhibited a high degree of matrix heterogeneity, with the ionic liquid phase preferentially forming at the fibres, resulting in poor matrix-dominated properties. However, fibre-dominated properties were not depressed. Thus, it was demonstrated that these materials can now offer weight savings over conventional monofunctional systems when under modest loading. KW - Carbon fibres KW - Functional composites KW - Mechanical properties KW - Elastic properties KW - Fractography PY - 2014 U6 - https://doi.org/10.1177/0021998314554125 SN - 0021-9983 SN - 1530-793X SP - 1 EP - 12 PB - Sage CY - London AN - OPUS4-34567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Marotzke, Christian T1 - mechanical properties of the fibre/matrix interface region of composite materials T2 - Eingeladener Vortrag Katholike Universitaet Leuven CY - Leuven, Belgium DA - 2010-07-01 PY - 2010 AN - OPUS4-23078 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard T1 - Mechanical characterization of the fiber-matrix interface in brittle and ductile polymers by using pull-out and push-out tests T2 - COMPO2014 Nanocomposites&Biocomposites, Weizmann Institute of Science CY - Rehovot, Israel DA - 2014-04-28 PY - 2014 AN - OPUS4-32037 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Greenhalgh, E.S. A1 - Ankersen, J. A1 - Asp, L. E. A1 - Bismarck, A. A1 - Fontana, Q.P.V. A1 - Houlle, M. A1 - Kalinka, Gerhard A1 - Kucernak, A. A1 - Mistry, M. A1 - Nguyen, S. A1 - Qian, H. A1 - Shaffer, M.S.P. A1 - Shirshova, N. A1 - Steinke, J.H.G. A1 - Wienrich, Malte T1 - Mechanical and microstructural characterisation of multifunctional structural power composites N2 - Although the inherent anisotropy of polymer composites has presented daunting technical challenges, these materials now offer engineers considerable opportunities for efficient structural design. More recently, the advent of multifunctional composites which can fulfill more than one role within a system has attracted considerable interest, providing designers with exciting opportunities to innovate. Of particular interest here are structural power composites, which simultaneously carry mechanical load whilst storing/delivering electrical energy. Although the development of these composites is highly challenging, often with conflicting constituent requirements, the STORAGE consortium has had considerable success in the development of these materials for automotive applications. The focus of this paper is structural supercapacitors, the basic architecture of a single cell of which is shown in Fig. 1. This entails two carbon fibre woven lamina (electrodes) which sandwich a glass fibre woven lamina (separator), all of which is embedded within a multifunctional matrix (electrolyte). This architecture has been the focus of the research to date, leading to components such as that shown in Fig.1 having been fabricated. This paper reports on the mechanical properties and microstructures of the different reinforcement and matrix combinations for structural supercapacitors. T2 - ICCM19 - 19th International conference on composite materials CY - Montreal, Canada DA - 28.07.2013 KW - Structural electrolyte KW - Multifunctional supercapacitor KW - Fractography KW - Ionic conductivity KW - Mechanical properties PY - 2013 SP - 2228 EP - 2237 AN - OPUS4-29272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hampe, Andreas A1 - Marotzke, Christian A1 - Kalinka, Gerhard T1 - Measurement of the Interfacial Toughness in Composites by Micromechanical Experiments T2 - 4th Arab International Conference on Polymer Science & Technology CY - Cairo, Egypt DA - 1997-09-08 PY - 1997 AN - OPUS4-5929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Qian, H. A1 - Kalinka, Gerhard A1 - Chan, K.L.A. A1 - Kazarian, S.G. A1 - Greenhalgh, E.S. A1 - Bismarck, A. A1 - Shaffer, M.S.P. T1 - Mapping local microstructure and mechanical performance around carbon nanotube grafted silica fibres: Methodologies for hierarchical composites N2 - The introduction of carbon nanotubes (CNTs) modifies bulk polymer properties, depending on intrinsic quality, dispersion, alignment, interfacial chemistry and mechanical properties of the nanofiller. These effects can be exploited to enhance the matrices of conventional microscale fibre-reinforced polymer composites, by using primary reinforcing fibres grafted with CNTs. This paper presents a methodology that combines atomic force microscopy, polarised Raman spectroscopy, and nanoindentation techniques, to study the distribution, alignment and orientation of CNTs in the vicinity of epoxy-embedded micrometre-scale silica fibres, as well as, the resulting local mechanical properties of the matrix. Raman maps of key features in the CNT spectra clearly show the CNT distribution and orientation, including a ‘parted’ morphology associated with long grafted CNTs. The hardness and indentation modulus of the epoxy matrix were improved locally by 28% and 24%, respectively, due to the reinforcing effects of CNTs. Moreover, a slower stress relaxation was observed in the epoxy region containing CNTs, which may be due to restricted molecular mobility of the matrix. The proposed methodology is likely to be relevant to further studies of nanocomposites and hierarchical composites. KW - Nanotubes KW - Silica fibres KW - Nano indentation KW - Mapping PY - 2011 U6 - https://doi.org/10.1039/c1nr10497g SN - 2040-3364 SN - 2040-3372 VL - 3 IS - 11 SP - 4759 EP - 4767 PB - RSC Publ. CY - Cambridge AN - OPUS4-34718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Munz, Martin A1 - Chung, Jae Un A1 - Kalinka, Gerhard ED - Possart, W. T1 - Mapping Epoxy Interphases T2 - 7th European Conference on Adhesion ; 7th EURADH CY - Freiberg, Germany DA - 2004-09-01 KW - Interface KW - Interphase KW - Epoxy KW - Copper (Cu) KW - Polyvinylpyrrolidone (PVP) KW - AFM/SFM KW - DSI KW - EDX/EDS KW - Stiffness KW - Modulus KW - Interdiffusion PY - 2005 SN - 3-527-31263-3 VL - 7 SP - 103 EP - 123 PB - Wiley-VCH CY - Weinheim AN - OPUS4-10894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rabe, T. A1 - Kalinka, Gerhard A1 - Mieller, Björn T1 - Manufacturing and deformation behavior of alumina and zirconia helical springs at room temperature N2 - Ceramic helical springs with identical dimensions were produced by hard machining from alumina, alumina toughened zirconia (ATZ), and tetragonal zirconia polycrystals (TZP) stabilized with different oxides. According to the results of the spring constant determination under deformation rates of 3 mm/min, the deformation behavior of all ceramic springs obeys to Hook’s law. However, variation of the deformation rate, tests under constant load, and spring recovery behavior revealed differences in the deformation behavior of alumina, TZP, and ATZ springs. Alumina springs exhibited time-independent deformation in all tests. In contrast, anelastic deformation at room temperature was demonstrated in all springs containing TZP. This deformation is completely reversible over a period of several days. Anelastic behavior is particularly pronounced in Y-TZP springs, whereas Ce-TZP springs exhibit comparatively very low but still reliably detectable anelasticity. Oxygen vacancies in the TZP ceramic are considered the most likely explanation for the anelastic behavior of TZP springs at room temperature. KW - Alumina KW - Creep KW - Elastic properties KW - Zirconia PY - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-571858 SN - 0002-7820 SP - 1 EP - 14 PB - Wiley-Blackwell CY - Oxford [u.a.] AN - OPUS4-57185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Marotzke, Christian T1 - Local mechanical relaxation time spectroscopy with using the nano indentation technique T2 - THERMOSETS 2009 CY - Berlin, Germany DA - 2009-10-01 PY - 2009 AN - OPUS4-20123 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marotzke, Christian A1 - Bohse, Jürgen A1 - Kalinka, Gerhard T1 - Local failure processes in fiber reinforced polymers T2 - International Conference on Composite Materials (ICCM17) CY - Edinburgh, Scotland DA - 2009-07-27 PY - 2009 AN - OPUS4-18372 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marotzke, Christian A1 - Kalinka, Gerhard T1 - Local failure processes in fiber reinforced polymers N2 - The breakage of a fiber and its effect on the strain energy is studied in a model composite, this is, a single fiber embedded in a dogbone specimen. The fracture process is recorded by an acoustic emission device, the crack patterns are monitored under a microscope. A finite element analysis is performed in order to estimate the energy released by different failure scenarios. The abilities and limitations of the acoustic emission analysis in characterizing different failure types in fiber reinforced composites are evaluated. T2 - ICCM17 - 17th International conference on composite materials CY - Edinburgh, UK DA - 2009-07-27 KW - Fiber KW - Interface KW - Composite material KW - Failure KW - Acoustic emission KW - Fracture mechanics KW - Energy release rate KW - Finite element analysis PY - 2009 IS - D7:8 SP - 1 EP - 10 CY - Edinburgh, UK AN - OPUS4-21295 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sturm, Heinz A1 - Schulz, Eckhard T1 - Local AC current contrast on carbon fiber surfaces imaged by scanning force microscopy N2 - After a delamination process in a C-fiber reinforced polymer composite, the identification of the polymer residue of poly-(phenylene sulphide) on carbon fiber surfaces gives important information on the composite failure mechanism. Using scanning force microscopy (SFM) in its lateral force imaging mode or with the stiffness imaging mode, it is almost impossible to distinguish the two composite components owing to a very low material-based contrast of the local friction and compliance. The new technique using contrast based on a local AC current measurement allows a clear identification of the conducting carbon fiber and the non-conducting polymer coverage. KW - Matrix adhesion KW - Films KW - Photoconduction KW - Composites PY - 1995 U6 - https://doi.org/10.1002/actp.1995.010460505 SN - 0323-7648 SN - 1521-4044 VL - 46 IS - 5 SP - 379 EP - 384 PB - Wiley-VCH Verl. CY - Weinheim, Germany AN - OPUS4-6848 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Camp, N. V. A1 - Kalinka, Gerhard A1 - Bergeler, J. T1 - Light-cured polymer electrodes for non-invasive EEG recordings N2 - We invented the first non-metallic, self-adhesive and dry biosignalling electrode. The PEDOT polymer electrode changes its aggregate state and conductivity by a light curing procedure. The electrode can be applied as a gel underneath hair without shaving. With the aid of blue light, the electrode can be hardened within a few seconds at the desired location on the scalp. The cured polymer electrode is highly conductive and can be applied on a very small location. Unlike other EEG electrodes, our electrode does not lose conductivity upon drying. Furthermore, our electrode strongly bonds to Skin and does not require any additional adhesive. Short circuits due to an outflow of gel are prevented with this technique. Therefore, the PEDOT polymer electrode is extremely well suited for applications that, up to now, have been challenging, such as non-invasive EEG recordings from awake and freely moving animals, EEG recordings from preterm babies in the neonatal intensive care unit or long-term recordings in the case of sleep monitoring or epilepsy diagnostics. We addressed two technical questions in this work. First, is the EEG recorded with polymer electrodes comparable to a standard EEG? Second, is it possible to record full-band EEGs with our electrodes? KW - Light curing KW - Polymer KW - Electric conductivity PY - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-459803 UR - https://rdcu.be/7aPD SN - 2045-2322 VL - 8 IS - 14041 SP - 1 EP - 9 PB - Nature Publishing Group CY - London AN - OPUS4-45980 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meretz, S. A1 - Lahser, K. A1 - Lehmann, V. A1 - Kalinka, Gerhard A1 - Hampe, Andreas T1 - Kristallisationskinetik bei Faserverbundwerkstoffen T2 - Kolloquium der Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin, Germany DA - 1993-10-01 PY - 1993 AN - OPUS4-12128 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griepentrog, Michael A1 - Beck, Uwe A1 - Reiners, Georg T1 - Kratzbeständigkeit Prüfmethoden und deren Bewertung N2 - Der Vortrag widmet sich der Kratzbeständigkeit-Prüfmethoden und deren Bewertung und beschreibt Begriffe/Definitionen, Wirtschaftliche Bedeutung der Kratzbeständigkeit, Mess- und Prüfverfahren – allgemein (Anwendbarkeit, Messunsicherheit, Validierung), Mess- und Prüfverfahren – speziell die Erzeugung, Prüfverfahren von Einzel- und Vielfach-Kratzern, die Charakterisierung von Verkratzungen und eine zusammenfassende Bewertung im Einzelnen T2 - SKZ-Seminare für die Kunststoff-Branche: Modifikation der Kratz- und Abriebbeständigkeit CY - Peine, Germany DA - 19.04.2016 KW - Kratzfestigkeit KW - Haftfestigkeit KW - Ritztest KW - Instrumentierte Eindringprüfung KW - Normung PY - 2016 AN - OPUS4-37598 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN ED - Rockland, Ulrike T1 - Jahresbericht 2013 T1 - Annual report 2013 T3 - BAM Reports/Jahresberichte - 2013 PY - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-4507 SN - 0934-9456 N1 - Volltext (PDF) in deutsch und englisch - Full text (PDF) in German and English VL - 2013 SP - 1 EP - 122 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-450 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN ED - Rockland, Ulrike T1 - Jahresbericht 2009 T1 - Annual report 2009 T3 - BAM Reports/Jahresberichte - 2009 PY - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-4546 SN - 0934-9456 N1 - Volltext (PDF) in deutsch und englisch - Full text (PDF) in German and English VL - 2009 SP - 1 EP - 118 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-454 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN ED - Rockland, Ulrike T1 - Jahresbericht 2008 T1 - Annual report 2008 T3 - BAM Reports/Jahresberichte - 2008 PY - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-4550 SN - 0934-9456 N1 - Volltext (PDF) in deutsch und englisch - Full text (PDF) in German and English VL - 2008 SP - 1 EP - 110 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-455 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN ED - Rockland, Ulrike T1 - Jahresbericht 2007 T1 - Annual report 2007 T3 - BAM Reports/Jahresberichte - 2007 PY - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-4564 SN - 0934-9456 N1 - Volltext (PDF) in deutsch und englisch - Full text (PDF) in German and English VL - 2007 SP - 1 EP - 153 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-456 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN ED - Rockland, Ulrike T1 - Jahresbericht 2006 T1 - Annual report 2006 T3 - BAM Reports/Jahresberichte - 2006 PY - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-4578 SN - 0934-9456 N1 - Volltext (PDF) in deutsch und englisch - Full text (PDF) in German and English VL - 2006 SP - 1 EP - 108 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-457 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN ED - Lexow, Jürgen T1 - Jahresbericht 2004 T1 - Annual report 2004 T3 - BAM Reports/Jahresberichte - 2004 PY - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-4592 SN - 0934-9456 VL - 2004 SP - 1 EP - 97 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-459 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN T1 - Jahresbericht 2002 T3 - BAM Reports/Jahresberichte - 2002 PY - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-4619 SN - 0934-9456 VL - 2002 SP - 1 EP - 282 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-461 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nowak, H. A1 - Kalinka, Gerhard A1 - Hinrichsen, G. T1 - Investigations on the cold crystallization of pure and filled PETP by dielectric measurements N2 - The cold crystallization of pure and filled poly(ethylene terephthalate) (PETP) after quenching from the melt has been investigated by dielectric measurements in two different modes: The first one using constant heating-rate (in the temperature range from 320 to 480 K) and the second one under isothermal conditions (at 378 K). The complex dielectric constant (ε´, tan δ) is influenced by crystallization. Two α-relaxation regions are identified: The αa-relaxation region from the pure amorphous phase and the α´-relaxation region from the spherulitic phase. The investigations on the filled systems (PETP + 10% aramid puple, PETP + 30% short glass fibres) prove that an influence of the fillers on the time delay and rate of crystallization and on the geometry of the growing spherulites exists. KW - Verbundwerkstoffe KW - Gefüllte Kunststoffe KW - Elektrische Eigenschaften KW - Verlustfaktor KW - Dielektrische Analyse PY - 1993 SN - 0323-7648 SN - 1521-4044 VL - 44 IS - 1 SP - 25 EP - 28 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-11995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schulz, Eckhard A1 - Kalinka, Gerhard A1 - Sturm, Heinz A1 - Munz, Martin T1 - Investigations of the mechanical behaviour of heterogeneous polymeric systems and fibre reinforced composites using micro indentation and scanning force microscopy T2 - Special Lectures, 18. Disc. Conf. And 56the PMM.: Mech. Behaviour of polymeric materials CY - Prague, Czech Republic DA - 1998-07-20 PY - 1998 AN - OPUS4-12092 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schulz, Eckhard A1 - Kalinka, Gerhard A1 - Sturm, Heinz A1 - Munz, Martin T1 - Investigation on mechanical behaviour of heterogeneous polymeric systems and fibre reinforced composites using micro indentation and scanning force microscopy T2 - 18th Disc. Conf. and 56th PMM CY - Prague, Czech Republic DA - 1998-07-20 PY - 1998 AN - OPUS4-6451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Elabshihy, Karim A1 - Kalinka, Gerhard T1 - Investigation of the time-dependent behavior of cnt-filled epoxy using nanoindentation N2 - Epoxy/Carbon nanotube (CNT) composites are interesting materials that could be used in a wide variety of applications. In this study, CNT contents of 0.25, 0.5, 1 and 2 wt% were used for reinforcing epoxy. A nanoindentation device and a temperature regulating system were developed in order to investigate the effect of CNTs on the time-dependent properties of epoxy using relaxations and creep tests on the nano scale. The relaxation tests showed a significant shift for the relaxation spectrum towards shorter times with introducing a low CNT content of 0.25 wt%. Additionally, creep tests showed that both the holding time at a constant load and the unloading velocity have a major effect on the contact stiffness. However, there was no effect for the CNTs on the creep behavior with contents lower than 1 wt%, which was related to the presence of a percolation threshold around this value. T2 - Nanobrücken 2013 CY - Dresden, Germany DA - 20.03.2013 KW - Epoxy KW - CNT KW - Time-dependent KW - Nanoindentation PY - 2013 AN - OPUS4-35533 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schulz, Eckhard A1 - Kalinka, Gerhard A1 - Leistner, André A1 - Sturm, Heinz A1 - Munz, Martin A1 - Hampe, Andreas T1 - Investigation of polymeric composites reinforced with high oriented short glass fibres using the single fibre push-out test T2 - Euro-Conf. Surfaces and Interfaces in Polymers and Composites CY - Lausanne, Switzerland DA - 1997-06-03 PY - 1997 AN - OPUS4-6439 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhandarov, S. A1 - Mäder, E. A1 - Kalinka, Gerhard A1 - Scheffler, C. A1 - Poitzsch, C. A1 - Fliescher, S. T1 - Investigation of interfacial strength parameters in polymer matrix composites: Compatibility and reproducibility N2 - Effects of various geometrical and physical factors, as well as the method of data reduction (analysis of experimental forceedisplacement curves) on the values of local interfacial strength parameters (local IFSS, td, and critical energy release rate, Gic) determined by means of a single fiber pull-out test are discussed. Experimental results of our pull-out tests on several fiberepolymer matrix systems showed that td and Gic weakly depended on geometrical factors. However, the pull-out test appeared to be sensitive to the conditions of specimen formation and testing, such as changing the nature of the contacting surfaces (fiber sizing) and the fiber pull-out rate. Of several methods of td and Gic Determination from a forceedisplacement curve, the most reliable and reproducible one is the approach based on the values of the maximum force recorded in a pull-out test and the interfacial frictional force immediately after fiber debonding. KW - Interface KW - Interfacial shear strength KW - Pull-out composite materials KW - Polymer matrix composites KW - Critical energy release rate KW - Geometrical factors PY - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-460918 SN - 2542-5048 VL - 1 IS - 1 SP - 82 EP - 92 PB - Elsevier CY - Amsterdam AN - OPUS4-46091 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Godara, A. A1 - Gorbatikh, L. A1 - Kalinka, Gerhard A1 - Warrier, A. A1 - Rochez, O. A1 - Mezzo, L. A1 - Luizi, F. A1 - van Vuure, A.W. A1 - Lomov, S.V. A1 - Verpoest, I. T1 - Interfacial shear strength of a glass fiber/epoxy bonding in composites modified with carbon nanotubes N2 - In recent years, carbon nanotubes (CNTs) grown on fibers have attracted a lot of interest as an additional reinforcing component in conventional fiber-reinforced composites to improve the properties of the fiber/matrix interface. Due to harsh growth conditions, the CNT-grafted fibers often exhibit degraded tensile properties. In the current study we explore an alternative approach to deliver CNTs to the fiber surface by dispersing CNTs in the fiber sizing formulation. This route takes advantage of the developed techniques for CNT dispersion in resins and introduces no damage to the fibers. We focus on unidirectional glass fiber/epoxy macro-composites where CNTs are introduced in three ways: (1) in the fiber sizing, (2) in the matrix and (3) in the fiber sizing and matrix simultaneously. Interfacial shear strength (IFSS) is investigated using single-fiber push-out microindentation. The results of the test reveal an increase of IFSS in all three cases. The maximum gain (over 90%) is achieved in the composite where CNTs are introduced solely in the fiber sizing. KW - A. Carbon nanotubes KW - A. Hybrid composites KW - A. Polymer-matrix composites (PMCs) KW - B. Interfacial strength PY - 2010 U6 - https://doi.org/10.1016/j.compscitech.2010.04.010 SN - 0266-3538 VL - 70 IS - 9 SP - 1346 EP - 1352 PB - Elsevier CY - Barking AN - OPUS4-22171 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Hampe, Andreas T1 - Interfacial properties and their determination by using stiffness optimized test devices T2 - Workshop on Micro-Mechanics Measurement Technologies, NIST CY - Gaithersburg, MD, USA DA - 1997-05-28 PY - 1997 AN - OPUS4-12103 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ho, K.K.C. A1 - Lamoriniere, S. A1 - Kalinka, Gerhard A1 - Schulz, Eckhard A1 - Bismarck, A. T1 - Interfacial behavior between atmospheric-plasma-fluorinated carbon fibers and poly(vinylidene fluoride) N2 - Atmospheric-plasma fluorination was used to introduce fluorine functionalities onto the surface of carbon fibers without affecting their bulk properties. The interfacial adhesion between atmospheric-plasma-fluorinated carbon fibers and poly(vinylidene fluoride) (PVDF) was studied by means of direct wetting measurements and single fiber pullout tests. Measured contact angles of PVDF melt droplets on modified carbon fibers show that short exposure times of carbon fibers to atmospheric-plasma fluorination (corresponding to a degree of surface fluorination of F/C = 0.01 (1.1%)) leads to improved wettability of the fibers by PVDF melts. The apparent interfacial shear strength as a measure of practical adhesion, determined by the single-fiber pullout test, increases by 65% under optimal treatment conditions. The improved practical adhesion is not due to the formation of transcrystalline regions around the fibers or a change of the bulk matrix crystallinity or to an increased surface roughness; it seems to be due to the compatibilization of the interface caused of the atmospheric-plasma fluorination of the carbon fibers. KW - Carbon fibers KW - Fluorination KW - Contact angle KW - Interface KW - Adhesion KW - Surface area KW - Fiber properties PY - 2007 U6 - https://doi.org/10.1016/j.jcis.2007.04.076 SN - 0021-9797 SN - 1095-7103 VL - 313 IS - 2 SP - 476 EP - 484 PB - Elsevier CY - Orlando, Fla. AN - OPUS4-16026 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marotzke, Christian A1 - Kalinka, Gerhard T1 - Interface Faser-Matrix - welche Rolle spielt das Interface bei der Festigkeit von Faserverbundwerkstoffen T2 - 15. Nationales SAMPE Symposium, BAM CY - Berlin, Germany DA - 2009-02-18 PY - 2009 AN - OPUS4-19016 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kalinka, Gerhard A1 - Schulz, Eckhard T1 - Influence of water on the fibre-matrix adhesion investigated by the single fiber indentation method T2 - 4th European Conference on Adhesion, 1st World Congress on Adhesion an Related Phenomena CY - Garmisch-Partenkirchen, Germany DA - 1998-09-06 PY - 1998 AN - OPUS4-12105 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Taketa, I. A1 - Kalinka, Gerhard A1 - Gorbatikh, L. A1 - Lomov, S. A1 - Verpoest, I. T1 - Influence of cooling rate on the properties of carbon fiber unidirectional composites with polypropylene, polyamide 6, and polyphenylene sulfide matrices N2 - The longitudinal and transverse strength of three unidirectional thermoplastic prepreg systems: carbon fiber/polypropylene (CF/PP), polyamide 6 (CF/PA6), and polyphenylene sulfide (CF/PPS) are studied and analytical formulas are proposed for the estimation of matrix and fiber/matrix interface properties from composites properties. Since the matrices are semi-crystalline thermoplastics, the influence of cooling rate on the strength is statistically evaluated. While the 0° tensile strength is found to be independent of the cooling rate, the 90° tensile strength is strongly influenced by the matrix type and cooling rate. The matrix modulus increases as the cooling rate is decreased; the degree of crystallinity also increases. The matrix residual stress, interfacial shear strength, and mode II interlaminar fracture toughness are also found to depend on the cooling rate, with the trends different for different matrices. KW - Matrix residual stress KW - Thermoplastic prepreg KW - Unidirectional composites KW - Cooling rate KW - Interfacial strength PY - 2020 U6 - https://doi.org/10.1080/09243046.2019.1651083 SN - 0924-3046 SN - 1568-5519 N1 - Die originale japanische Version des Artikels erschien in: Journal of the Japan Society for Composite Materials, Jg. 44, Nr. 4 (2018), S. 123-128. - The original Japanese version of the article was published in: Journal of the Japan Society for Composite Materials, vol. 44, no. 4 (2018), pp. 123-128. VL - 29 IS - 1 SP - 101 EP - 113 PB - Taylor & Francis CY - London AN - OPUS4-45433 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sturm, Heinz A1 - Silbernagl, Dorothee A1 - Ghasem Zadeh Khorasani, Media T1 - Improving polymer matrix additives for composite structures: a focus on boehmite N2 - The aims of the Research Unit „Acting Principles of Nano-Scaled Matrix Additives for Composite Structures“ (DFG FOR 2021) are based on different synergetic pathways. Challenges are to achieve an improved damage tolerance combined with unchanged processability and a proof of the nano-based effect from molecular scale up to structural level. First of all, a comprehensive understanding of the acting mechanisms of nano-scaled ceramic additives onto polymer matrices of continuous fibre reinforced polymer composites with respect to improved matrix dominated properties is in focus. To proof of the nanoscopic and microscopic effects up to structural level; experimental investigations start on the functional correlation between the particle properties and the resulting properties of the epoxy as suspension and in the solid state. This includes tests for the resulting composite structures as well. Along the entire process chain different multi-scale simulations are performed from molecular modelling up to the macroscopic, structural level. The combination of experimental investigations and simulation methods enables a holistic understanding of the acting principles and basic mechanisms. Specialized techniques based on Scanning Force Microscopy are the basis of our analysis of physicochemical properties of the boehmite nanoparticles and their polymer environment. A surface map of mechanical properties as an input for simulations facilitate a deeper understanding of such composites across all scales. This enables us to understand the macroscopic structure-property relationship and to predict failure mechanisms as well as routes for optimization. T2 - 92nd DKG annual meeting and symposium on high performance ceramics CY - Berlin, Germany DA - 19.03.2017 KW - Boehmite nanoparticle KW - Intermodulation AFM KW - Composite structures KW - Pull-out test KW - Thermoset KW - Crack propagation energy PY - 2017 AN - OPUS4-39519 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -