TY - JOUR A1 - Altmann, Korinna A1 - Schulze, Rolf-Dieter A1 - Hidde, Gundula A1 - Friedrich, Jörg Florian T1 - Elektrospray-Ionisation (ESI) - Lochfreie elektrophoretische Abscheidung von ultra-dünnen Polymerschichten N2 - Die Elektrospray-Ionisations (ESI)-Vernebelung von Polymerlösungen wird analytisch zur massenspektrometrischen Bestimmung der Molmassen von Makromolekülen genutzt. Dabei werden die Polymermoleküle nach einem speziellen Mechanismus im Hochspannungsfeld unter Normaldruckbedingungen vereinzelt und in das Massenspektrometer überführt. Dieser Prozeß kann auch zur flächigen Abscheidung einzelner Polymermoleküle genutzt werden. Die Struktur und Zusammensetzung sowie die Molmassenverteilung der Polymere bleiben dabei erhalten. Schichten polarer oder ionischer Polymere der Dicke einer Quasi-Monolage bis hin zu mehreren 100 Nanometern können abgeschieden werden. Erwähnenswert ist, daß der ESI-Prozeß zu den elektrophoretischen Verfahren gehört, was die Ausbildung lochfreier Schichten auf elektrisch leitenden Substraten nicht nur auf der der Spraydüse zugewandten Seite ermöglicht, sondern auch auf der abgeschatteten Rückseite. Dieses Verhalten wurde zur vollständigen ESI-Umhüllung von dichtgepackten Kohlenstoff-Faser-Bündeln mit haftvermittelnden Polymerschichten ausgenutzt. PY - 2011 U6 - https://doi.org/10.1002/vipr.201100471 SN - 0947-076X SN - 1522-2454 VL - 23 IS - 6 SP - 17 EP - 23 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-25392 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Altmann, Korinna A1 - Schulze, Rolf-Dieter A1 - Hidde, Gundula A1 - Friedrich, Jörg-Florian T1 - Electrospray ionization for deposition of ultra-thin polymer layers – principle, electrophoretic effect and applications N2 - Nebulizing of polymer solutions, in a high-voltage field under atmospheric conditions by electrospray ionization (ESI), is a comfortable way to deposit ultra-thin layers of polar or ionic polymers onto any conductive substrate materials. The substrate is grounded and the polymer solution is sprayed through a powered capillary. The formed charged droplets shrink by solvent evaporation during their way to the grounded substrate, the charges close ranks and the droplets collapse consecutively by charge repulsion, thus forming finally charged single macromolecules. After their discharging at the grounded substrate, an ultrathin ‘quasi-monomolecular’ polymer layer is formed. It could be shown by imaging of scratches through the polymer layer by atomic force microscopy that the deposited polymer layers are dense at a thickness of about 10 nm. Carbon fibre bundles were coated with poly (allylamine) (PAAm) or poly(acrylic acid) (PAA) as potential adhesion-promoting layers in fibre–polymer composites. The polymer deposition is self-inhibiting after formation of a continuous coverage of about 200 nm for PAAm and 30 nm for PAA as result of surface charging. Continuous deposition onto such isolating layers or polymers without charging can be achieved by using current of alternating polarity. The film formation is self-healing because of the electrophoretic effect, i.e. the ion discharging occurs preferentially at noncoated areas. This electrophoretic effect of ESI was demonstrated by completely enwrapping all the carbon fibres of the roving within a distance of about 100 μm far from its outside and also at the backside of the fibre bundle with about 80% of the topside coverage, as measured by X-ray photoelectron spectroscopy and visualized using scanning electron microscopy. KW - Complete enwrapping of fibres KW - Ultra-thin polymer layers KW - Self-healing KW - Electrospray deposition KW - Carbon fibres KW - Electrophoretic effect PY - 2012 U6 - https://doi.org/10.1080/01694243.2012.727170 SN - 0169-4243 VL - 27 IS - 9 SP - 988 EP - 1005 PB - Taylor & Francis CY - London AN - OPUS4-42631 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - An, Q. A1 - Bäßler, Ralph A1 - Hertwig, Andreas A1 - Rehfeldt, Rainer A1 - Hidde, Gundula A1 - Otremba, Frank T1 - Investigation of Mechanical Stress and B10 Exposure on FKM Polymer N2 - Mechanical stress often accelerates the failure of polymer materials. The aim of this research is to study the interaction between the sealing material FKM and biofuels B10 (heating oil with 10% biodiesel). The mechanical stress test was carried out in a special apparatus. Both mechanical and non-mechanical stress tests were conducted on specimens at 20, 40, and 70 °C for 28 days to document changes in mass, volume, and tensile properties. Both increasing temperature and mechanical stress have a significant effect on the tensile strength of the FKM polymer when exposed to B10. The combination of increasing temperature and mechanical stress induced rupture within 2 h. It was also established that FKM polymer with pre-exposure in B10 survived longer during mechanical stress compared to specimens exposed only to air. With the support of infrared (IR) spectroscopy, we were able to confirm the penetration of B10 into the FKM polymer. T2 - TMS 2024 Annual Meeting & Exhibition Teilnahme mit Präsentation CY - Orlando-Florida / USA DA - 03.03.2024 KW - Biofuels KW - Sealing materials KW - Mechanical stress KW - Change in tensile properties PY - 2024 U6 - https://doi.org/10.1007/978-3-031-50349-8_108 SP - 1253 EP - 1261 PB - Springer CY - Orlando-Florida / USA AN - OPUS4-59638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Jennifa A1 - Beck, Uwe A1 - Hidde, Gundula A1 - Hielscher, Stefan A1 - Lange, Thorid A1 - Mix, Renate T1 - Plasmagestützte Oberflächenfunktionalisierung von Polypropylen (PP) N2 - Polypropylen (PP) ist als Niedrigenergie-Polymer ohne nass- und plasmachemische Vorbehandlung weder haftfest zu beschichten noch verbundfest zu kleben. Typische Haft- bzw. Klebfestigkeiten liegen für die unbehandelte Polymeroberfläche bei maximal 0,5 MPa. Hinzu kommt, dass bei der Bestimmung von Haft- und Klebfestigkeiten der unmodifizierten Oberfläche mit großen Streuungen zu rechnen ist, die bezogen auf die Spannweite durchaus einem Faktor 5 entsprechen können. Generell besteht bei Prüfung der Haftfestigkeit mittels Stirnabzugsversuch und bei der Prüfung der Klebfestigkeit die Notwendigkeit eines statistisch validierten Herangehens. Hierzu sind zeitaufwändige Ein-Proben-Klebungen und -Prüfungen nur eingeschränkt geeignet. Zudem ist, insbesondere für geringe Haft- bzw. Klebfestigkeiten, ein querkraftfreies Prüfen Grundvoraussetzung. Im vorliegenden Beitrag werden verschiedenartige plasmagestützte Oberflächenfunktionalisierungen von PP sowie das Mehr-Proben-Konzept zur Klebung/Prüfung von bis zu acht Proben vorgestellt. Dazu werden ein BAM-Funktionsmuster einer Mehr-Proben-Kleb-Vorrichtung und eine kommerzielle analytische Zentrifuge zum Prüfen verwendet. T2 - 24. Workshop des Anwenderkreises Atmosphärendruckplasma "Haftung durch Oberflächenfunktionalisierung" CY - Erfurt, Germany DA - 11.11.2015 KW - Plasmamodifizierung KW - Polypropylen KW - Haftfestigkeit KW - Klebfestigkeit KW - Mehr-Proben-Kleben/-Prüfen PY - 2015 SP - 1 EP - 6 PB - Anwenderkreis Atmosphärendruckplasma CY - Jena AN - OPUS4-34838 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baier, Jennifa A1 - Hidde, Gundula A1 - Beck, Uwe T1 - Oberflächenaktivierung von Polymeren mittels O2-Plasma N2 - Zur Verbesserung der Verbundfestigkeit kann beim Kleben [1] oder Beschichten von Polymeren die Oberfläche mittels 02-Plasma gereinigt (Feinstreinigung) und aktiviert werden. Bei der Plasmaaktivierung werden sauerstoffhaltige funktionelle Gruppen auf der Oberfläche gebildet. Die Polymersubstrate wurden mit 02-Plasma behandelt, zum einen mit einem Plasmajet bei 200 W (PP, PA) und zum anderen mit einem Mikrowellenplasma bei 100 W (Folie: PE, PP, PS, PC, PET), mittels FTIR-Spektroskopie (p-ATR) charakterisiert sowie die Änderung der Oberflächenenergie mittels Kontaktwinkelmessung bestimmt. T2 - 10. ThGOT Thementage Grenz- und Oberflächentechnik mit 4. Optik-Kolloquium CY - Leipzig, Germany DA - 02.09.2014 KW - Plasma KW - Oberflächenaktivierung PY - 2014 SP - 1 EP - 2 AN - OPUS4-31337 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Beck, Uwe A1 - Baier, Jennifa A1 - Hidde, Gundula A1 - Hielscher, Stefan A1 - Kittler-Packmor, Kai A1 - Lange, Thorid A1 - Mix, Renate A1 - Weise, Matthias T1 - Multiple-sample approach: reliable ranking and validated statistics of bonding and adhesive strength N2 - Bonding strength of adhesive-bonded joints and adhesive strength of coatings have been exclusively determined in single-sample tests using a tensile testing machine. Necessarily, the single-sample approach was also applied to the corresponding bonding procedure. As a consequence, reliability and reproducibility of results were restricted. By applying the newly introduced centrifuge technology, the multiple-sample approach was realized for simultaneous tensile testing of up to eight samples under identical conditions without any disturbing shear-force effects. In order to introduce the multiple-sample approach into the bonding procedure, a hydraulic bonding set-up was developed which enables identical bonding pressure also for slightly different heights of sample assemblies. Both sample approaches were compared for various application examples: ranking of different classes of adhesives, validated statistics of adhesive-bonded joints using one particular adhesive and effects of cleaning and plasma-treatment on the adhesive strength of coatings. The investigated systems included glass, metals and polymer substrates, different adhesives, metallic and dielectric coatings on polymers. KW - Bonding strength KW - Adhesive strength KW - Multi-sample approach KW - Centrifuge technology PY - 2014 SN - 978-3-944261-28-7 SN - 978-3-944261-36-2 SN - 978-3-944261-52-2 VL - 5 SP - 1 EP - 5 AN - OPUS4-31310 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Baier, Jennifa A1 - Hidde, Gundula A1 - Hielscher, Stefan A1 - Kittler-Packmor, Kai A1 - Lange, Thorid A1 - Mix, Renate A1 - Weise, Matthias T1 - Multiple-sample approach: reliable ranking and validated statistics of bonding and adhesive strength N2 - Bonding strength of adhesive-bonded joints and adhesive strength of coatings have been exclusively determined in single-sample tests using a tensile testing machine. Necessarily, the single-sample approach was also applied to the corresponding bonding procedure. As a consequence, reliability and reproducibility of results were restricted. By applying the newly introduced centrifuge technology, the multiple-sample approach was realized for simultaneous tensile testing of up to eight samples under identical conditions without any disturbing shear-force effects. In order to introduce the multiple-sample approach into the bonding procedure, a hydraulic bonding set-up was developed which enables identical bonding pressure also for slightly different heights of sample assemblies. Both sample approaches were compared for various application examples: ranking of different classes of adhesives, validated statistics of adhesive-bonded joints using one particular adhesive and effects of cleaning and plasma-treatment on the adhesive strength of coatings. The investigated systems included glass, metals and polymer substrates, different adhesives, metallic and dielectric coatings on polymers. T2 - EURADH 2014 - 10th European Adhesion Conference CY - Alicante, Spain DA - 22.04.2014 KW - Bonding strength KW - Adhesive strength KW - Multi-sample approach KW - Centrifuge technology PY - 2014 SN - 978-84-616-9067-1 SN - 84-616-9067-2 SP - Paper 49, 211 EP - 214 AN - OPUS4-31309 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Farag, Zeinab A1 - Moustapha, M. A1 - Hidde, Gundula A1 - Friedrich, Jörg A1 - Azzam, M. A1 - Krüger, Simone ED - Mital, K.L. T1 - Promotion of Adhesion of Green Flame Retardant Coatings onto Polyolefins by Depositing Ultra-Thin Plasma Polymer Films N2 - Various methods have been used for introducing fire retardant additives into polymers. Deposition of thick fire retardant coatings directly onto polymer substrates is an alternative technique. An important advantage of the coating technique is the preservation of the physical and chemical integrity of the polymer material. Moreover, the fire retardancy of the polymer materials can be achieved following their production. Suitable coating materials are inorganics, intumescent, char-forming, oxygendiluting, and cooling or radical quenching layers. The most important problem is to achieve sufficient coating thickness to withstand the direct attack of flame and to protect the polymer bulk from pyrolysis, otherwise blistering of coating, caused by emitted pyrolysis gases, is often observed. To avoid blistering of coating, the adhesion between polyolefin substrate and fire retardant coating has to be extraordinarily high. In order to achieve such a high level of adhesion, the polymer surface has to be modified with adhesion-promoting functional groups. The deposition of thin plasma polymers as adhesion-promoting layers with NH2, OH or COOH groups has been the most suited method. These functional groups are able to form covalent bonds and other interactions between the fire-resistant coating and the plasma-modified polyolefin substrate. Additionally, the plasma polymer counteracts the strong mechanical stresses in the laminate on exposure to high temperatures by its flexibility. KW - Plasma KW - Adhesion PY - 2017 SN - 978-1-119-40748-5 SN - 978-1-119-40638-9 U6 - https://doi.org/10.1002/9781119407485 VL - 2 SP - 399 EP - 427 PB - Scrivener Publishing CY - Beverly, USA AN - OPUS4-47227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Farag, Zeinab Ramadan A1 - Friedrich, Jörg Florian A1 - Krüger, Simone A1 - Hidde, Gundula A1 - Moustapha, M. E. T1 - Adhesion promotion of thick polyphosphate-poly(allylamine) films onto polyolefin substrates by plasma polymers N2 - The adhesion of thick poly(allylamine)-polyphosphate layers (1 µm) deposited by the wet-chemical layer-by-layer technique (LbL) onto polyethylene or polystyrene (each 100 µm) was very low. To promote the adhesion of these LbL layers the polyolefin substrates were oxidized at the surface by short exposure to the oxygen plasma (2 or 5 s) and subsequently coated with an interlayer of plasma-deposited poly(allylamine) or poly(allyl alcohol) (100 nm). The plasma polymer interlayers have improved strongly the adhesion between polyolefin substrates and polyphosphate coatings. Such phosphate coatings are interesting for life sciences (nucleotide formation) but also for fire retardancy in combination with N-rich compounds such as melamine. The intention was to prefer chemical and hydrogen bonds for adhesion promoting because of their high binding energy. Therefore, the introduced oxygen-containing groups at the polyolefin surface could interact with the OH or NH2 groups of the adhesion-promoting plasma polymer interlayer. These groups were also able to interact strongly with the poly(allylamine)-polyphosphate topcoating. The coated polyolefins were investigated using Fourier Transform Infrared Spectroscopy in Attenuated Total Reflectance mode (FTIR-ATR), X-ray Photoelectron Spectroscopy (XPS), Thermo-Gravimetric Analyses (TGA) and Atomic Force Spectroscopy (AFM) and 90° peel test. KW - Plasma-polymerized poly(allylamine) KW - Adhesion KW - Layer-by-layer deposition KW - Plasma polymerization PY - 2016 UR - http://www.tandfonline.com/doi/abs/10.1080/01694243.2015.1095626 U6 - https://doi.org/10.1080/01694243.2015.1095626 SN - 1648-4142 VL - 30 IS - 3 SP - 231 EP - 246 PB - Taylor & Francis AN - OPUS4-35885 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg A1 - Altmann, Korinna A1 - Wettmarshausen, Sascha A1 - Hidde, Gundula T1 - Coating of carbon fibers with adhesion-promoting thin polymer layers using plasma polymerization or electrospray ionization technique—A comparison N2 - Plasma polymers and electrospray-ionization (ESI) polymer layers are compared for most efficient adhesion promotion in carbon fiber-epoxy resin composites. The ultra-thin ESI layers (2–30 nm) of commercial poly(acrylic acid) and poly-(hydroxyethylmethacrylate) produce an significant increase of adhesion measured by single-fiber pull out tests. However, plasma Treatment has also advantages, such as simultaneous activation of the fiber substrate. Chemical structure and composition are rather far from the regular structure of commercial polymers as deposited by ESI processing. KW - Plasma polymers KW - Electrospray ionization polymers KW - Poly(acrylic acid) KW - Poly- (hydroxyethylmethacrylate) PY - 2017 U6 - https://doi.org/10.1002/ppap.201600074 SN - 1612-8869 SN - 1612-8850 VL - 14 IS - 3 SP - e1600074-1 EP - 14 AN - OPUS4-40510 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -