TY - JOUR A1 - Lippitz, Andreas A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang T1 - Plasma bromination of HOPG surfaces: a NEXAFS and synchrotron XPS study N2 - Br bonding on plasma brominated graphite surfaces has been studied by using Near Edge X-ray Absorption Fine Structure (NEXAFS) and X-ray Photoelectron Spectroscopy (XPS). Br2 and bromoform were used as plasma gases in an r.f. cw low pressure plasma process. Kr plasma had been used to study separately the physical and chemical plasma etching effects. At early steps of plasma bromination which lead to only small XPS Br surface concentration values a quick decay of aromaticity has been observed. At low Br surface concentration radical or even electrophilic addition of bromine onto sp2 carbon atoms is discussed as the dominating reaction pathway. At higher Br surface concentrations the inherent formation of sp3 defects in the graphene network by chemical etching processes promotes nucleophilic substitution of bromine at sp3 carbons as a competing reaction pathway. Both reaction pathways lead to C–Br species characterized by the same Br 3d XPS binding energy. However more than one Br 3d component in XP spectra has been found at lower Br2 plasma induced Br surface concentrations and complexation of bromine at HOPG is assumed as a third way of interaction with Br2 plasma. KW - HOPG KW - Graphite KW - Plasma bromination KW - Low pressure plasma KW - NEXAFS KW - XPS PY - 2013 DO - https://doi.org/10.1016/j.susc.2013.01.020 SN - 0039-6028 VL - 611 SP - L1 EP - L7 PB - Elsevier CY - Amsterdam AN - OPUS4-27928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Mix, Renate A1 - Friedrich, Jörg Florian A1 - Inagaki, N. ED - Thomas, M. ED - Mittal, K.L. T1 - Permanence of functional groups at polyolefin surfaces introduced by dielectric barrier discharge pretreatment in presence of aerosols N2 - A convenient way to overcome the chemical inertness of polyolefin surfaces is to expose them to the atmospheric air plasma of a dielectric barrier discharge (DBD). To improve the efficiency in formation of polar groups at the polyolefin surface, different liquids such as water and ethanol were sprayed as aerosol into the plasma zone between the powered electrode and the polyolefin surface. Both sprayed liquids as well as the polyolefin surface were simultaneously activated; thus, the formation of different functional groups at the polyolefin surface was realized. The type of aerosol-sprayed additive, exposure time, power etc. have been found to determine the efficiency with respect to introduction of polar groups. KW - PE KW - PP KW - Surface modification KW - Aerosol-assisted DBD PY - 2013 SN - 978-1-118-59621-0 DO - https://doi.org/10.1002/9781118747308.ch4 N1 - Serientitel: Adhesion and Adhesives: Fundamental and applied aspects – Series title: Adhesion and Adhesives: Fundamental and applied aspects IS - Part 1 / Chapter 4 SP - 131 EP - 156 PB - Wiley AN - OPUS4-28657 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Jörg Florian A1 - Mix, Renate T1 - Combination of plasma-chemical and wet-chemical processes - a simple way to optimize interfaces in metal-polymer composites for maximal adhesion N2 - Different surface treatments of polypropylene (PP) were tested to improve the peel strength of aluminium-PP systems. Plasma exposure followed by chemical grafting of spacers with -SiOH endgroups and thin adhesion promoting layers deposited by aerosol-assisted DBD using aqu. solutions of classic polymers were compared. Both methods were effective, however, –SiOH terminated spacers effected no peeling also after ageing. T2 - ISPC 21 - 21st International Symposium on Plasma Chemistry CY - Cairns, QLD, Australia DA - 02.08.2013 KW - Adhesion polypropylene-aluminium KW - Tailored interface structures KW - Aerosol-assisted DBD PY - 2013 SP - Paper 549, 1 EP - 4 AN - OPUS4-28661 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zeynalov, Eldar A1 - Friedrich, Jörg Florian A1 - Meyer-Plath, Asmus A1 - Hidde, Gundula A1 - Nuriyev, L. A1 - Aliyeva, A. Z. A1 - Cherepnova, Y. T1 - Plasma-chemically brominated single-walled carbon nanotubes as novel catalysts for oil hydrocarbons aerobic oxidation N2 - Brominated single-walled carbon nanotubes [(Br)n-SWCNT) produced by the plasma-chemical technique were involved in the liquid-phase process of hydrocarbons aerobic oxidation. The significant catalytic effect of the (Br)n-SWCNT was revealed at first by the cumene initiated model oxidation and then in experiments on profound aerobic oxidation of petroleum naphthenic fraction derived from the commercial Azerbaijan (Baku) oils blend diesel cut. The ability of (Br)n-SWCNT to accelerate the aerobic oxidation of the hydrocarbons was found out for the first time. Obviously this phenomenon originates from the peculiarities of electronic configuration of the (Br)n-CNT patterns. The plausible mechanism of (Br)n-SWCNT catalytic action is inclined to the formation of reactive oxygen species. The catalytic activity of (Br)n-SWCNT markedly exceeds the activity of the industrial catalysts, manganese salt of indigenous petroleum acids, used for the liquid phase petroleum hydrocarbons oxidation process. KW - Brominated carbon nanotubes KW - Plasma-chemical technique KW - Model cumene oxidation KW - Oxidation rate KW - Oxidation catalysts KW - Oil hydrocarbons liquid-phase oxidation KW - Manganese naphthenate KW - Synthetic petroleum acids PY - 2013 DO - https://doi.org/10.1016/j.apcata.2013.01.003 SN - 0926-860X SN - 1873-3875 VL - 454 SP - 115 EP - 118 PB - Elsevier CY - Amsterdam AN - OPUS4-28290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mohamed, Zeinab A1 - Krüger, Simone A1 - Hidde, Gundula A1 - Schimanski, A. A1 - Jäger, Christian A1 - Friedrich, Jörg Florian T1 - Deposition of thick polymer or inorganic layers with flame-retardant properties by combination of plasma and spray processes N2 - Mixtures of hexamethyldisiloxane (HMDSO) and oxygen have been used for deposition of SiO2-like layers by plasma polymerization under low-pressure conditions onto polyethylene and polystyrene used as basecoat. Water glass was cast onto these 0.5 µm plasma thick siloxane-like layers with a thickness of 5 to 40 µm. The adhesion of these bilayer systems and their flame resistance were tested. The effect of different plasma parameters such as monomer/gas ratio, pressure and power input into the discharge on the deposition rate and the composition of the formed layers was studied. Characterization and chemical composition of the formed films were performed using infrared, X-ray photoelectron and solid state nuclear magnetic resonance spectroscopy. Peel strengths of composites were measured and the locus of peel front propagation was detected. Thermal properties of composites were analyzed by thermo-gravimetric analysis. Finally, the fire-retardant properties of thick coated polymers were determined by exposure to flames and the behavior of coatings on the polymers during flaming was observed visually. KW - Plasma polymerization KW - Hexamethyldisiloxane plasma polymer KW - Polystyrene KW - Polyethylene KW - Flame retardancy PY - 2013 DO - https://doi.org/10.1016/j.surfcoat.2013.04.039 SN - 0257-8972 VL - 228 SP - 266 EP - 274 PB - Elsevier B.V. CY - Lausanne AN - OPUS4-28735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Joshi, Ranjit A1 - Friedrich, Jörg Florian A1 - Krishna-Subramanian, S. T1 - Surface modification of ultra-high molecular weight polyethylene membranes using underwater plasma polymerization N2 - Ultra-high molecular weight polyethylene membranes were modified and subsequently polymer coated using the underwater plasma produced by glow discharge electrolysis. This plasma pretreatment generated various O-functional groups among them OH groups have dominated. This modified inner (pore) surface of membranes showed complete wetting and strong adhesion to a hydrogel copolymerized by glow discharge electrolysis also. The deposited hydrogel consists of plasma polymerized acrylic acid crosslinked by copolymerization with the bifunctional N,N'-methylenebis(acrylamide). Tuning the hydrogel hydrophilicity and bio-compatibility poly(ethylene glycol) was chemically inserted into the copolymer. Such saturated polymer could only be inserted on a non-classic way by (partial) fragmentation and recombination thus demonstrating the exotic properties of the underwater plasma. The modification of membrane was achieved by squeezing the reactive plasma solution into the pores by plasma-induced shock waves and supported by intense stirring. The deposited copolymer hydrogel has filled all pores also in the inner of membrane as shown by scanning electron microscopy of cross-sections. The copolymer shows the characteristic units of acrylic acid and ethylene glycol as demonstrated by infrared spectroscopy. A minimum loss in carboxylic groups of acrylic acid during the plasma polymerization process was confirmed by X-ray photoelectron spectroscopy. Additional cell adhesion tests on copolymer coated polyethylene using IEC-6 cells demonstrated the bio-compatibility of the plasma-deposited hydrogel. KW - Glow discharge electrolysis (GDE) KW - UHMWPE membrane KW - Pore modification KW - Adhesion KW - Copolymer hydrogel PY - 2013 DO - https://doi.org/10.1007/s11090-013-9476-2 SN - 0272-4324 VL - 33 IS - 5 SP - 921 EP - 940 PB - Plenum Publ. Corp. CY - New York, NY, USA AN - OPUS4-29335 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Kühn, Gerhard A1 - Schulz, Ulrich A1 - Jansen, Kirsten A1 - Möller, B. A1 - Fischer, S. T1 - Fluorination of Polymer Surfaces PY - 2002 SN - 0947-076X SN - 1522-2454 VL - 14 IS - 5 SP - 285 EP - 290 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-1466 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schartel, Bernhard A1 - Kühn, Gerhard A1 - Mix, Renate A1 - Friedrich, Jörg Florian T1 - Surface Controlled Fire Retardancy of Polymers Using Plasma Polymerisation N2 - Communication: Fire retardant coatings are deposited on polyamide-66 using plasma polymerisation. Chemical composition and thickness of deposits are adjusted varying the plasma treatment based on hexamethydisiloxane mixed with oxygen. The fire retardancy performances are evaluated using a cone calorimeter. The correlation between fire retardancy and thickness as well as chemical composition is discussed. KW - Cone calorimeter KW - Flame retardance KW - Heat release KW - Plasma polymerization KW - Polyamides PY - 2002 DO - https://doi.org/10.1002/1439-2054(20020901)287:9<579::AID-MAME579>3.0.CO;2-6 SN - 1438-7492 SN - 1439-2054 VL - 287 IS - 9 SP - 579 EP - 582 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-1537 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schulze, Rolf-Dieter A1 - Friedrich, Jörg Florian T1 - Pulsed r.f. plasma for polymer film deposition with SEERS diagnostic T2 - 8th International Conference on Plasma Surface Engineering (PSE2002) CY - Garmisch-Partenkirchen, Germany DA - 2002-09-09 KW - C pulsed KW - C radio frequency KW - C plasma KW - D nitrogen KW - D oxygen KW - DX plasma deposition PY - 2002 SN - 0257-8972 SP - 405 PB - Elsevier Science CY - Lausanne AN - OPUS4-1615 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Friedrich, Jörg Florian A1 - Retzko, Iris A1 - Kühn, Gerhard A1 - Unger, Wolfgang A1 - Lippitz, Andreas ED - Mittal, K. T1 - Metal doped plasma polymer films T2 - 7th Symposium on Metallized Plastics CY - Newark, NJ, USA DA - 1999-12-02 KW - Plasma polymer KW - r.f. pulsed plasma KW - Conducting films KW - Metal-polymer interface PY - 2001 SN - 90-6764-340-8 VL - 7 SP - 117 EP - 142 PB - VSP CY - Utrecht AN - OPUS4-929 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Geng, Sh. A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Erdmann, J. A1 - Gorsler, H.-V. T1 - Plasma functionalization and reorientation of macromolecules at polymer surfaces KW - Plasma KW - Polymer KW - Monolayer KW - Einschichtsystem KW - NEXAFS KW - Spektroskopie KW - Oberflächenanalyse PY - 1995 SN - 0257-8972 VL - 74-75 SP - 664 EP - 669 PB - Elsevier Science CY - Lausanne AN - OPUS4-627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Wigan, L. A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Erdmann, J. A1 - Gorsler, H.-V. T1 - Barrier properties of plasma and chemically fluorinated polypropylene and polyethyleneterephthalate N2 - The functionalization, perfluorination or an coating of polypropylene (PP) and polyethyleneterephthalate (PET) surfaces in different plasma atmospheres and in an F[2] + N[2] gas mixture were investigated. The aim of this work was to form a barrier layer against solvent and fuel permeation. Typical test solvents were n-pentane, toluene, tetrachloroethylene and mixtures of n-pentane and methanol. The permeation was gravimetrically measured. The permeation of the solvent mixtures was analyzed by mass spectrometry and Fourier transform IR spectroscopy. The permeation of the solvent mixtures through the plasma-modified polymer samples was associated with increased absorption of polar solvent components in the polymer film. The thickness of the plasma-fluorinated PP surface layer was 10-100 nm and that of chemically fluorinated PP about 5000 nm. Nearly the same barrier efficiency was measured for both plasma- and chemically fluorinated samples. T2 - International Conference on Plasma Surface Engineering No. 4 CY - Garmisch-Partenkirchen, Germany DA - 1994-09-19 KW - Plasma KW - Fluor KW - Plasmapolymer KW - Sperrschicht KW - Permeation PY - 1995 UR - http://cat.inist.fr/?aModele=afficheN&cpsidt=3158319 SN - 0257-8972 VL - 74-75 IS - 1-3 SP - 910 EP - 918 PB - Elsevier Science CY - Lausanne AN - OPUS4-628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lippitz, Andreas A1 - Koprinarov, Ivaylo A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Weiss, K. A1 - Wöll, Ch. T1 - Surface analysis of metaillized poly(bisphenol A cabonate) films by x-ray absorption spectroscopy (NEXAFS) KW - NEXAFS KW - Röntgenadsorptionsspektroskopie KW - Oberflächenanalyse KW - Film, metallisiert KW - Polymeroberfläche PY - 1996 SN - 0032-3861 SN - 1873-2291 VL - 37 IS - 14 SP - 3157 EP - 3160 PB - Springer CY - Berlin AN - OPUS4-649 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lippitz, Andreas A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Schertel, A. A1 - Wöll, Ch. T1 - Surface analysis of partially crystalline and amorphous poly(ethylene terephthalate) samples by x-ray absorption spectroscopy (NEXAFS) KW - NEXAFS KW - Röntgenadsorptionsspektroskopie KW - Oberflächenanalyse KW - Polymeroberfläche PY - 1996 SN - 0032-3861 SN - 1873-2291 VL - 37 IS - 14 SP - 3151 EP - 3155 PB - Springer CY - Berlin AN - OPUS4-650 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Lippitz, Andreas A1 - Koprinarov, Ivaylo A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Schertel, A. A1 - Wöll, Ch. T1 - NEXAFS analysis of a plasma treated, partially crystalline poly(ehtylene terephtalate) surface KW - NEXAFS KW - Röntgenstrukturanalyse KW - Oberflächen behandeln KW - Plasma PY - 1996 SN - 0179-4159 SP - 279 EP - 281 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-681 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Gross, Thomas A1 - Friedrich, Jörg Florian A1 - Wöll, Ch. A1 - Nick, L. T1 - The Use of Octadecyltrichlorosilane Self-Assembled Layers as a Model for the Assessment of Plasma Treatment and Metallization Effects on Polyolefins N2 - Self-assembled octadecyltrichlorosilane (CH3(CH2)17SiCl3, OTS) films were deposited on an oxidized silicon wafer. They were carefully exposed to a low-pressure oxygen direct current (dc) plasma and/or Cr vapor. Subsequently, they were characterized by X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy, and atomic force microscopy. Detailed information on the oxygen functionalization and the molecular conformation of the OTS films was obtained. The main result was that functionalization conditions can be found where the order of the film remains almost unaffected. Similarly, Cr evaporation of pure OTS films revealed only slight effects on the order in the film. Cr evaporation of an ordered but functionalized OTS film immediately changes its state toward a fully isotropic one. In the course of interaction, oxygen sites at the surface of the functionalized OTS film are reduced whereas Cr becomes oxidized. A redox reaction scheme is proposed for this interfacial reaction. Finally, it is concluded that the given study should be of importance for advanced plasma processing of polyolefins. KW - NEXAFS KW - OTS Self-Assembled Layers PY - 1999 DO - https://doi.org/10.1021/la981174l SN - 0743-7463 SN - 1520-5827 VL - 15 IS - 4 SP - 1161 EP - 1166 PB - American Chemical Society CY - Washington, DC AN - OPUS4-808 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Koprinarov, Ivaylo A1 - Giebler, Rainer A1 - Lippitz, Andreas A1 - Unger, Wolfgang T1 - Reactions and Intermediates at the Metal-Polymer Interface as Observed by XPS and NEXAFS Spectroscopy KW - XPS KW - NEXAFS KW - Interfacial polymer-metal redox reactions KW - Chromium-polymer intermediates KW - Near edge X-ray absorption fine structure spectroscopy KW - Adhesion KW - Polymer-metal bonds KW - Polymer-aluminium bonds KW - Polymer-copper bonds PY - 1999 SN - 0021-8464 SN - 1545-5823 VL - 71 SP - 297 EP - 321 PB - Gordon & Breach CY - New York, NY AN - OPUS4-798 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoffmann, Katrin A1 - Mix, Renate A1 - Resch-Genger, Ute A1 - Friedrich, Jörg Florian T1 - Fluorescence Measurements on Functionalized Polymer Surfaces - Problems and Troubleshooting KW - Fluorescence spectroscopy KW - Polymer functionalization KW - Surface labeling KW - Pyrylium label PY - 2008 DO - https://doi.org/10.1196/annals.1430.015 SN - 0077-8923 SN - 1749-6632 SN - 0094-8500 VL - 1130 SP - 28 EP - 34 PB - New York Academy of Sciences CY - New York, NY AN - OPUS4-17567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoffmann, Katrin A1 - Resch-Genger, Ute A1 - Mix, Renate A1 - Friedrich, Jörg Florian T1 - Fluorescence Spectroscopic Studies on Plasma-Chemically Modified Polymer Surfaces with Fluorophore-Labeled Functionalities N2 - Molecular engineering of polymer surfaces that includes the attachment of functional molecules to existing or previously generated reactive chemical groups like e.g., - OH, - NH2, or - CHO requires simple strategies and tools for the controlled generation of surface functionalities and their derivatization as well as for their identification and eventually quantification. Here, we systematically investigate the plasma-chemical surface modification of polypropylene films in combination with dansyl labeling chemistry and conventional, yet costly, XPS and highly sensitive fluorescence spectroscopy for the detection of surface groups. Based on these results, the potential of and requirements on the fluorometric characterization and quantification of surfaces functionalities are discussed. KW - Fluorescence spectroscopy KW - Surface functionalization KW - Covalent labeling of polymer surfaces KW - Plasma modification KW - Fluorescent probe PY - 2006 DO - https://doi.org/10.1007/s10895-006-0076-x SN - 1053-0509 SN - 1573-4994 VL - 16 IS - 3 SP - 441 EP - 448 PB - Plenum Publ. Corp. CY - New York, NY AN - OPUS4-12560 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Kühn, Gerhard A1 - Mix, Renate A1 - Hoffmann, Katrin A1 - Resch-Genger, Ute T1 - Tailoring of polymer surfaces with monotype functional groups of variable density using chemical and plasma chemical processes N2 - Polymer surfaces were modified in low-pressure glow discharge plasmas for introduction of monotype functional groups of different type and density. For this purpose three ways are selected, (i) oxygen plasma treatment followed by wet-chemical reduction of O functional groups to OH groups, (ii) plasma bromination for introducing C - Br groups and (iii) coating by deposition of thin plasma (co-) polymerized layers of functional groups-bearing monomers with OH, NH2, COOH, epoxy etc. functionalities. Subsequently, these groups were used as anchoring points for chemical grafting of spacer molecules, oligomers, prepolymers, fluorescent labels, ionic and nucleic acid residues, employing different chemical routes. The yield in monosort functional groups at polymer surfaces ranged from 10–14 (process i), 20–40 (process ii) and 18–31 groups per 100 C atoms (process iii) as measured by XPS after derivatization. The consumption of functional groups amounted to 40–90% of all functionalities present at the surface and depended on the dimensions of grafted molecules. For infinitely variably tuning the number of functional groups process iii was performed as copolymerization of a functional group-carrying comonomer with a non-functionalized (“chain-extending”) comonomer. KW - Introduction of functional groups KW - Plasma modification KW - Reactions at Polymer surfaces PY - 2006 SN - 0340-255x SN - 1437-8027 VL - 132 SP - 62 EP - 71 PB - Springer CY - Berlin AN - OPUS4-12515 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hoffmann, Katrin A1 - Mix, Renate A1 - Friedrich, Jörg Florian A1 - Resch-Genger, Ute ED - Geddes, C.D. T1 - Spectroscopic characterization of plasma - Chemically functionalized and fluorophore-labeled polymer surfaces N2 - The potential of spectrofluorometry and fluorescence microscopy for the characterization and quantification of different functionalities like OH and NH2 groups at plasma-chemically modified polymer surfaces is assessed using traditional reactive dyes such as dansyl derivatives and a sophisticated VIS-excitable chromogenic and fluorogenic pyrylium label showing binding-induced spectral and intensity changes in absorption and emission. Aiming at an improved fluorometric surface analysis, based upon these measurements, several sources of uncertainty inherent to fluorescence measurements are illustrated ranging from environment-dependent dye absorption and emission features over spectral correction and nonspecific adsorption to the critical influence of label choice on the measured background. Solutions to these drawbacks are given thereby underlining the potential of fluorometry for surface analysis. KW - Polymer functionalization KW - Plasma modification KW - Fluorescence spectroscopy KW - Surface labeling PY - 2010 SN - 978-1-4419-0828-5 DO - https://doi.org/10.1007/978-1-4419-1260-2_6 N1 - Serientitel: Reviews in Fluorescence – Series title: Reviews in Fluorescence VL - 5 SP - 139 EP - 160 PB - Springer Science + Business Media AN - OPUS4-21274 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mix, Renate A1 - Hoffmann, Katrin A1 - Buschmann, H.-J. A1 - Friedrich, Jörg Florian A1 - Resch-Genger, Ute T1 - Anbindung von Fluoreszenzfarbstoffen an plasmachemisch funktionalisierte und Cucurbituril-modifizierte Oberflächen N2 - Plasmapolymerisierte Allylaminschichten (50 nm) wurden auf Polypropylenfolien abgeschieden. Die auf diese Weise generierte NH2-funktionalisierte Polymeroberfläche wurde mit Xanthen-Fluorophoren chemisch umgesetzt. Da die Farbstoff-gekoppelten Folien nur geringe Fluoreszenz aufwiesen, wurden zwei Wege zur möglichen Entkopplung der Farbstoffe von der Oberfläche und damit zur Erhöhung der Fluoreszenzintensität getestet. Als erstes wurde ein Spacer durch die Umsetzung der primären Aminogruppen mit Glutaraldehyd und der nachfolgenden Kettenverlängerung mit Diaminohexan eingeführt. Diese nachfolgende Reaktion ergab eine spacergebundene NH2-Oberfläche, die analog der Allylaminschicht mit den Farbstoffen umgesetzt wurde. Als weiterer Weg wurde der Zusatz einer geeigneten Käfigverbindung, des Cucurbit[6]urils, getestet. Die spacergebundenen und zusätzlich mit Cucurbituril modifizierten aminofunktionellen Oberflächen zeigten nach der Farbstoffankopplung eine verbesserte Fluoreszenzintensität. KW - Fluoreszenz KW - Spacer KW - Cucurbituril PY - 2007 DO - https://doi.org/10.1002/vipr.200700329 SN - 0947-076X SN - 1522-2454 VL - 19 IS - 5 SP - 31 EP - 37 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-16000 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoffmann, Katrin A1 - Mix, Renate A1 - Friedrich, Jörg Florian A1 - Buschmann, H.-J. A1 - Resch-Genger, Ute T1 - Anchoring of Fluorophores to plasma-chemically modified polymer surfaces and the effect of Cucurbit[6]uril on dye emission N2 - Polypropylene supports were functionalized by plasma-deposition of polymeric allylamine layers. The surface amino groups generated were wet-chemically reacted with xanthene dyes resulting in fluorescent polymer films. The effect of polymer-attachment of the dyes on their emission features was studied fluorometrically and different methods were tested to improve the fluorescence properties of the films. Modification with cucurbit[6]uril (CB6) yields a moderately enhanced fluorescence as well as an improved photostability. The observed effect is most likely due to CB6-induced rigidization of the linker molecules which seems to reduce fluorescence quenching dye–dye and fluorophore–surface interactions. KW - Fluorescence KW - Cucurbituril KW - Surface modification KW - Plasma functionalization KW - Polymer surface KW - Xanthene dyes PY - 2009 DO - https://doi.org/10.1007/s10895-008-0407-1 SN - 1053-0509 SN - 1573-4994 VL - 19 SP - 229 EP - 237 PB - Plenum Publ. Corp. CY - New York, NY AN - OPUS4-19154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mix, Renate A1 - Hoffmann, Katrin A1 - Resch-Genger, Ute A1 - Decker, Renate A1 - Friedrich, Jörg Florian ED - Mittal, K. T1 - Covalent coupling of fluorophores to polymer surface-bonded functional groups KW - Plasma modification KW - Fluorescence KW - Surface functionalization KW - Reactions at polymer surfaces KW - Spectroscopy KW - Quantification PY - 2007 SN - 978-90-6764-453-2 VL - 4 SP - 171 EP - 191 PB - VSP CY - Utrecht AN - OPUS4-14867 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoffmann, Katrin A1 - Mix, Renate A1 - Resch-Genger, Ute A1 - Friedrich, Jörg Florian T1 - Monitoring of Amino Functionalities on Plasma-Chemically Modified Polypropylene Supports with a Chromogenic and Fluorogenic Pyrylium Reporter N2 - A straightforward strategy toward the sensitive fluorometric detection of primary amino groups on plasma-chemically modified polypropylene supports is presented, exploiting the transformation of the sterically nonhindered pyrylium dye Py-1 into its pyridinium counterpart. The reaction-induced blue-shifted absorption and emission bands and an increased fluorescence quantum yield provide the basis for the spectroscopic distinction between covalently bound and free, that is, nonspecifically adsorbed label molecules. With this label, for the first time, plasma-chemically introduced amino functionalities could be monitored on the surface of a polymer film employing fluorescence spectroscopy and confocal laser scanning microscopy. KW - Fluorescence spectroscopy KW - Surface characterization KW - Covalent labeling KW - Plasma modification KW - Fluorescent label PY - 2007 UR - http://pubs.acs.org/cgi-bin/abstract.cgi/langd5/2007/23/i16/abs/la7004908.html SN - 0743-7463 SN - 1520-5827 VL - 23 IS - 16 SP - 8411 EP - 8416 PB - American Chemical Society CY - Washington, DC AN - OPUS4-15717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mix, Renate A1 - Hoffmann, Katrin A1 - Decker, Renate A1 - Friedrich, Jörg Florian A1 - Resch-Genger, Ute ED - Blasek, G. T1 - Möglichkeiten der kovalenten Anbindung von Funktionsmolekülen an Polymeroberflächen T2 - 13. Neues Dresdner Vakuumtechnisches Kolloquium "Beschichtung und Modifizierung von Kunststoffoberflächen" CY - Dresden, Deutschland DA - 2005-10-13 PY - 2005 SP - 35 EP - 41 PB - VDI-Verl. CY - Dresden AN - OPUS4-11946 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lukowiak, M.C. A1 - Wettmarshausen, Sascha A1 - Hidde, Gundula A1 - Landsberger, Petra A1 - Boenke, Viola A1 - Rodenacker, K. A1 - Braun, Ulrike A1 - Friedrich, Jörg Florian A1 - Gorbushina, Anna A1 - Haag, R. T1 - Polyglycerol coated polypropylene surfaces for protein and bacteria resistance N2 - Polyglycerol (PG) coated polypropylene (PP) films were synthesized in a two-step approach that involved plasma bromination and subsequently grafting hyperbranched polyglycerols with very few amino functionalities. The influence of different molecular weights and density of reactive linkers were investigated for the grafted PGs. Longer bromination times and higher amounts of linkers on the surface afforded long-term stability. The protein adsorption and bacteria attachment of the PP-PG films were studied. Their extremely low amine content proved to be beneficial for preventing bacteria attachment. PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-325406 DO - https://doi.org/10.1039/c4py01375a SN - 1759-9954 SN - 1759-9962 VL - 6 IS - 8 SP - 1350 EP - 1359 AN - OPUS4-32540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Sturm, Heinz A1 - Schulz, Eckhard A1 - Stark, Wolfgang A1 - Bovtun, V. A1 - Friedrich, Jörg Florian ED - Olefjord, I. ED - Nyborg, L. ED - Briggs, D. T1 - Techniques for surface composition analysis with scanning force microscopy (SFM) using electrical surface properties T2 - 7th European Conference on Applications of Surface and Interface Analysis CY - Göteborg, Sweden DA - 1997-06-16 PY - 1997 SN - 0-471-97827-2 SP - 579 EP - 582 PB - Wiley CY - Chichester AN - OPUS4-6854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Friedrich, Jörg Florian A1 - Mix, Renate A1 - Wettmarshausen, Sascha A1 - Sturm, Heinz ED - Tachibana, K. ED - Takai, O. T1 - A new concept of adhesion promotion in metal-polymer composites by introduction of covalently bonded hydrophobic spacers at interface T2 - Proceedings of the 18th International Symposium on Plasma Chemistry (ISPC-18) CY - Kyoto, Japan DA - 2007-08-26 PY - 2007 SN - 978-4-9903773-4-2 SP - 27A EP - p5, 1 PB - International Union of Pure and Applied Chemistry CY - Kyoto AN - OPUS4-20668 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fahmy, A. A1 - Mix, Renate A1 - Schönhals, Andreas A1 - Friedrich, Jörg Florian T1 - Structure of plasma-deposited copolymer films prepared from acrylic acid and styrene: Part I dependence on the duty cycle N2 - Copolymers of acrylic acid and styrene (AA/S) were prepared by pulsed plasma deposition and their structures were studied in dependence on the duty cycle (DC) for a fixed composition of 1:1. As a result, low values of DC doses preserve the structure of monomers in the plasma deposited polymers while high DC leads to a higher degree of fragmentation and a loss in regular structure. Regarding plasma copolymerisation as a feasible method to finish surfaces with a definite number of functional groups it is necessary to characterize both, the chemical nature and the physical properties of the deposited layer. Therefore, a combination of different methods was employed for the characterization of thin plasma copolymer films (FTIR, dielectric spectroscopy, differential scanning calorimetry, X-ray photoelectron spectroscopy (XPS)). Special attention was paid on the unambiguous identification of COOH groups at the surface after derivatization with trifluoroethanol by XPS and in the volume by FTIR. The glass transition temperature of the copolymer system is lower than that for the both plasma deposited homopolymers and increases with the DC in difference to plasma deposited poly(acrylic acid). The dielectric measurements showed that the plasma deposited films were not thermally stable and underwent an undesired post-plasma chemical reaction. The results obtained by dielectric spectroscopy are discussed in detail in comparison with the data from FTIR and XPS measurements. KW - Plasmapolymerisation KW - Copolymerisation KW - Acrylic acid–styrene copolymer KW - Dynamic mobility KW - Plasma copolymerisation KW - Surface functionalization KW - Thin film properties PY - 2012 DO - https://doi.org/10.1002/ppap.201100117 SN - 1612-8850 SN - 1612-8869 VL - 9 IS - 3 SP - 273 EP - 284 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-25654 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mix, Renate A1 - Friedrich, Jörg Florian A1 - Inagaki, N. T1 - Modification of branched polyethylene by aerosol-assisted dielectric barrier discharge N2 - Three polyethylene (PE) types with different branching structures were subjected to air, water and ethanol aerosol-assisted dielectric barrier discharges (DBD) for surface modification. Using the air DBD the incorporated oxygen concentration was found to be independent on the branching of PE in contrast to the introduction of OH groups, which was PE-2 > PE-1 > PE-3. For water-aerosol DBD the succession of OH concentration was in the order of PE-1 > PE-2 > PE-3. Ethanol aerosol-assisted DBD produced the lowest concentration of OH groups also independent on the branching of PE. The chemical nature of introduced oxygen functional groups was inspected by X-ray photoelectron spectroscopy (XPS) and assigned as C–O, >C=O/CHO/O–C–O and O=C–O. KW - PE KW - Surface modification KW - Aerosol-assisted DBD PY - 2012 DO - https://doi.org/10.1002/ppap.201100052 SN - 1612-8850 SN - 1612-8869 VL - 9 IS - 4 SP - 406 EP - 416 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-25748 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mix, Renate A1 - Hielscher, Stefan A1 - Beck, Uwe A1 - Friedrich, Jörg Florian T1 - Plasma meets chemistry: Combined methods for tailored interface design in metal-polymer composites by selective chemical reactions on plasma modified surfaces N2 - The applicability of polymer-metal composites is mainly determined by the durability of the adhesive strength between both components. Aluminium (Al) deposited on polypropylene (PP) exemplifies different options of interface design. By deposition of plasma polymers on PP the effect of the type of the functionality was investigated. Spacer insertion was accomplished to position the functional group away from the topmost surface. A further kind of interface design involved a partial condensation of functional groups. Hydroxyl and carboxyl groups were most effective to improve adhesion in Al-PP systems. Approximately 7-10 carboxyl or 25-27 hydroxyl groups per 100 C atoms were necessary to increase the peel strength up to ~700 N/m. In this range, the failure of the composite propagated along the interface Al-tape (no peeling of the metal). Spacer molecules between surface and functional groups provoked the effect that the number of needed functional groups for maximum adhesion was strongly reduced. Linking of the functional groups resulted in non-peelable Al-PP laminates. Two adhesion tests were applied - the peel test and the centrifuge technology. For PP foils modified with chemically bonded and additionally linked silanol groups (no peeling) an adhesive strength of (2.5 ± 0.2) N/mm² was determined by centrifuge technology. XPS inspection of both fracture surfaces indicated a sub-surface failure in the polymer. T2 - HTPP-12 - 12th High-tech plasma processes conference CY - Bologna, Italy DA - 24.06.2012 KW - Adhesion PP-Al KW - Modified surfaces KW - Interface design PY - 2012 DO - https://doi.org/10.1088/1742-6596/406/1/012004 SN - 1742-6588 SN - 1742-6596 VL - 406 SP - 012004-1 - 012004-11 PB - IOP Publ. CY - Bristol, UK AN - OPUS4-28658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Natte, Kishore A1 - Behnke, Thomas A1 - Orts Gil, Guillermo A1 - Würth, Christian A1 - Friedrich, Jörg Florian A1 - Österle, Werner A1 - Resch-Genger, Ute T1 - Synthesis and characterisation of highly fluorescent core-shell nanoparticles based on Alexa dyes N2 - Current and future developments in the emerging field of nanobiotechnology are closely linked to the rational design of novel fluorescent nanomaterials, e.g. for biosensing and imaging applications. Here, the synthesis of bright near infrared (NIR)-emissive nanoparticles based on the grafting of silica nanoparticles (SNPs) with 3-aminopropyl triethoxysilane (APTES) followed by covalent attachment of Alexa dyes and their subsequent shielding by an additional silica shell are presented. These nanoparticles were investigated by dynamic light scattering (DLS), transmission electron microscopy (TEM) and fluorescence spectroscopy. TEM studies revealed the monodispersity of the initially prepared and fluorophorelabelled silica particles and the subsequent formation of raspberry-like structures after addition of a silica precursor.Measurements of absolute fluorescence Quantum yields of these scattering particle suspensions with an integrating sphere setup demonstrated the influence of dye labelling density-dependent fluorophore Aggregation on the signaling behaviour of such nanoparticles. KW - Silica KW - Alexa dyes KW - Fluorescent particles KW - Quantum yields KW - Nanoparticles KW - Protective shell KW - Nanobiotechnology PY - 2012 DO - https://doi.org/10.1007/s11051-011-0680-9 SN - 1388-0764 SN - 1572-896X VL - 14 IS - 2 SP - 680-1 - 680-10 PB - Kluwer CY - Dordrecht AN - OPUS4-25872 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hanelt, Sven A1 - Friedrich, Jörg Florian A1 - Meyer-Plath, Asmus T1 - UV spectrometric indirect analysis of brominated MWCNTs with UV active thiols and an alkene-reaction kinetics, quantification and differentiation of adsorbed bromine and oxygen N2 - Indirect UV-absorption spectrometry was shown to be a valuable tool for chemical characterization of functionalized carbon nanotubes (CNTs). It complements data from X-ray photoelectron spectroscopy (XPS) or FTIR analysis since it helps to clarify the type and concentration of functional groups. The principles of indirect application of UV-spectrometry and its mathematical interpretation are discussed. Their facile application, together with their adequate sensitivity and high flexibility, make UV-absorption-based approaches a valuable alternative to fluorescence spectrometry. Here, the approach was applied to the chemical analysis of oxidizing substances on CNTs. For this, pristine CNTs of low but finite oxygen content as well as brominated CNTs were analyzed by reaction in suspension with UV-active thiol reagents and a styrene derivative. It was shown that carefully selected reagents allow differentiation and quantification of bromine and generally oxidizing entities like oxygen. For brominated CNTs, it was shown that physisorbed bromine may dominate the overall bromine content. KW - Carbon nanotubes KW - CNTs KW - UV-spectrometry KW - Bromination KW - Thiols KW - Mercaptans KW - Disulfides KW - Quantification KW - Kinetics PY - 2013 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-289077 DO - https://doi.org/10.3390/ma6083035 SN - 1996-1944 VL - 6 IS - 8 SP - 3035 EP - 3063 PB - MDPI CY - Basel AN - OPUS4-28907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ramanujam, Maalolan A1 - Wachtendorf, Volker A1 - Purohit, Purv A1 - Mix, Renate A1 - Schönhals, Andreas A1 - Friedrich, Jörg Florian T1 - A detailed dielectric relaxation spectroscopy study of artificial UV weathered low density polyethylene N2 - Artificial weathering of LDPE under dry conditions (<10% of relative humidity) by UV radiation was monitored by dielectric spectroscopy. For an apolar polymer like LDPE, dielectric study yields Information about the change in structure and dynamics of the system. The fluctuations of the polar groups which are generated as a result of photooxidation such as carbonyl groups can be monitored as characteristic relaxation processes like the αc or β mode. The dielectric loss characterized by typical dielectric parameters like the activation energy and dielectric strength are strongly dependent upon changes induced by photooxidation in the amorphous and crystalline domains. This paper discusses in detail how the foil reached its mechanical disintegration. It was found that initial stages of weathering induce chain scission and/or crosslinking in the amorphous domains of the polymer and the motional processes in the crystalline regions are not affected. After this induction period, an increase in the degree of crystallization was observed by employing differential calorimetry. The increasing crystallinity is considered as one of the reasons for embrittlement which finally leads to the complete loss of the structural integrity. KW - Artificial weathering KW - UV radiation KW - Dielectric relaxation KW - LDPE PY - 2012 DO - https://doi.org/10.1016/j.tca.2011.12.003 SN - 0040-6031 SN - 1872-762X VL - 530 SP - 73 EP - 78 PB - Elsevier CY - Amsterdam AN - OPUS4-25547 LA - eng 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 - 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 DO - 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 - Friedrich, Jörg Florian T1 - Polymer deposition morphology by electrospray deposition - Modifications through distance variation N2 - Electrospray deposition (ESD) of highly diluted polymers was examined with regard to the deposited surface structure. Only the flight distance (flight time) onto the resulting deposited surface was varied from 20 to 200 mm. An apparatus without any additional heating or gas flows was used. Polyacrylic acid (PAA) and polyallylamine (PAAm) in methanol were deposited on Si wafers. The polymer layers were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, derivatization reactions and Fourier transform infrared spectroscopy using a grazing incidence unit. SEM images illustrated the changing structures of PAA and PAAm. For PAA the deposited structure changed from a smooth film (20 mm) to a film with individual droplets on the coated surface (100 mm and 200 mm), while for PAAm individual droplets can be seen at all distances. The ESD process with cascades of splitting droplets slows down for PAA after distances greater than 40 mm. In contrast, the ESD process for PAAm is nearly stopped within the first flight distance of 20 mm. Residual solvent analysis showed that most of the solvent evaporated within the first 20 mm capillary-sample distance. KW - Electrospray ionization KW - Electrospray deposition KW - Ultra-thin layers KW - Capillary-sample distance KW - Residual solvent PY - 2014 DO - https://doi.org/10.1016/j.tsf.2014.06.020 SN - 0040-6090 VL - 564 SP - 269 EP - 276 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-31252 LA - eng 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 DO - 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 - 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 DO - 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 - TY - JOUR A1 - Weidner, Steffen A1 - Kühn, Gerhard A1 - Decker, Renate A1 - Roessner, D. A1 - Friedrich, Jörg Florian T1 - Influence of Plasma Treatment on the Molar Mass of Poly(ethylene terephthalate) Investigated by Different Chromatographic and Spectroscopic Methods N2 - The influence of different types of low and atmospheric pressure plasma on poly(ethylene terephthalate) (PET) has been studied in terms of changes in molar mass and molar mass distribution. Apart from a variation of plasma gases (oxygen, helium) different types of plasma (microwave, radio frequency, corona discharge) were used for the plasma surface modification. The changes in molar mass and types of functional end groups of lower molar mass products were investigated by means of matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOFMS), whereas the high-molar mass fraction was analyzed by means of size-exclusion chromatography (SEC). The formation of crosslinked products during exposure to a helium plasma, which emits preponderately energy-rich and intense ultraviolet radiation, was proved by means of thermal field-flow fractionation (ThFFF). This method combined with a multiangle laser light scattering (MALLS) detector allows detection of weakly crosslinked polymers and microgels. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1639-1648, 1998 KW - Poly(ethylene terephthalate) KW - PET KW - Plasma PY - 1998 UR - http://www3.interscience.wiley.com/cgi-bin/abstract/36482/ABSTRACT DO - https://doi.org/10.1002/(SICI)1099-0518(19980730)36:10<1639::AID-POLA17>3.0.CO;2-H SN - 0360-6376 SN - 0887-624X VL - 36 IS - 10 SP - 1639 EP - 1648 PB - Wiley CY - Hoboken, NJ AN - OPUS4-6989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hanelt, Sven A1 - Friedrich, Jörg Florian A1 - Orts Gil, Guillermo A1 - Meyer-Plath, Asmus T1 - Study of Lewis acid catalyzed chemical bromination and bromoalkylation of multi-walled carbon nanotubes N2 - Chemical functionalization of carbon nanotubes (CNT) with nucleophiles requires introduction of electrophilic reactive sites on the CNTs. This can, for instance, be accomplished by the chemical bromination procedure with elemental bromine and a set of Lewis acids (BBr3, BF3 × Et2O, AlBr3, FeBr3, ZnBr2, TiBr4, SiBr4, SnBr4, VBr3) or a radical starter like dibenzoylperoxide (DBPO) in appropriate solvents at varied temperature. The present approach to electrophilic sites relies on the well-known electrophilic aromatic substitution or addition of bromine with aromatic structural units. In addition to the use of bromine, the introduction of haloalkyl groups was also investigated here using bis-electrophiles or haloalcohols and Brønsted acids. The advantages and drawbacks of the studied reaction conditions, the obtained degree of bromination as analyzed by X-ray photoelectron spectroscopy (XPS) and the amount of introduced bromine that can be substituted by a nucleophile are presented and discussed. KW - Carbon nanotubes KW - Bromierung KW - Lewis Säure KW - Bromalkylierung KW - CNT PY - 2012 DO - https://doi.org/10.1016/j.carbon.2011.11.009 SN - 0008-6223 SN - 1873-3891 VL - 50 IS - 3 SP - 1373 EP - 1385 PB - Pergamon Press CY - New York, NY AN - OPUS4-25207 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Koprinarov, Ivaylo A1 - Weidner, Steffen A1 - Kühn, Gerhard ED - Nowack, H. T1 - Wechselwirkungen zwischen plasmamodifizierten Polymeroberflächen und Metallen T2 - 5. Internationale Fachtagung - ND-Plasma-Technologie CY - Duisburg, Deutschland DA - 1997-09-22 PY - 1997 VL - 5 SP - 1(?) EP - 17(?) PB - Print-Service CY - Mülheim AN - OPUS4-6995 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidner, Steffen A1 - Falkenhagen, Jana A1 - Much, Helmut A1 - Krüger, Ralph-Peter A1 - Friedrich, Jörg Florian T1 - Determination of chemical and molecular-weight distributions of heterogeneous polymers by means of MALDI-MS coupled with chromatography T2 - 219th ACS national meeting CY - San Francisco, CA, USA DA - 2000-03-26 PY - 2000 SN - 0032-3934 VL - 41 IS - 1 SP - 655 EP - 656 PB - American Chemical Society CY - Newark, NJ AN - OPUS4-2169 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kühn, Gerhard A1 - Ghode, Archana A1 - Weidner, Steffen A1 - Retzko, Iris A1 - Unger, Wolfgang A1 - Friedrich, Jörg Florian ED - Mittal, K. L. T1 - Chemically well-defined surface functionalization of polyethylene and polypropylene by pulsed plasma modification followed by grafting of molecules T2 - 2nd International Symposium on Polymer Surface Modification: Relevance to Adhesion CY - Newark, NJ, USA DA - 1999-05-24 KW - Plasma modification KW - Chemical conversion of functional groups KW - Spacers KW - Polypropylene KW - Polyethylene PY - 2000 SN - 90-6764-327-0 VL - 2 SP - 45 EP - 64 PB - VSP CY - Utrecht AN - OPUS4-6975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Jörg Florian A1 - Gerstung, Vanessa A1 - Mix, Renate A1 - Kühn, Gerhard A1 - Weidner, Steffen ED - d'Agostino, R. T1 - Pulsed plasma initiated homo- and copolymerisation - molar masses T2 - 16th International Symposium on Plasma Chemistry (ISPC-16) CY - Taormina, Italy DA - 2003-06-22 PY - 2003 IS - CD-ROM PB - Dep. of Chemistry, Univ. CY - Bari AN - OPUS4-2710 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Ralph-Peter A1 - Falkenhagen, Jana A1 - Much, Helmut A1 - Schulz, Günter A1 - Friedrich, Jörg Florian T1 - Beiträge zur Charakterisierung von synthetischen Si-Polymeren durch Kopplung von HPLC-Trennmethoden mit der MALDI-TOF-MS T2 - DFG-Symposium zum Schwerpunktprogramm "Silicium-Chemie" CY - Werfenweng, Österreich DA - 2000-09-27 PY - 2000 AN - OPUS4-2251 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Falkenhagen, Jana A1 - Friedrich, Jörg Florian A1 - Schulz, Günter A1 - Krüger, Ralph-Peter A1 - Much, Helmut A1 - Weidner, Steffen T1 - Liquid Adsorption Chromatography near Critical Conditions of Adsorption coupled with Matrix-assisted Laser Desorption/Ionization Mass Spectrometry N2 - Chemical heterogeneities and molecular weight distributions of poly(ethylene oxide) (PEO)-co-polymethylene (PM) model oligomers, which are relevant to the synthesis of commonly used tensides, were investigated. For analytical characterization, the well-known principle of liquid adsorption chromatography at 'critical conditions' (LACCC) was modified. Near the critical conditions of adsorption of the PEO unit, e.g., at slight adsorption conditions of PM, the copolymers could be separated according to their PM chain length. The eluates were separated and single fractions of each peak were continuously transferred onto the MALDI target by means of a commercially available device. Simultaneously, the MALDI matrix solution was continuously added with a second pump. This procedure offers the possibility of the formation of homogeneous matrix-polymer textures. By MALDI-MS a complete characterization of the chemical composition (PEO and PM chain length) of each peak could be achieved. The obtained MALDI mass spectra of the eluates at different retention times could be used for the molecular weight calibration of the LAC system. In this way, an additional application of SEC, as in conventional 2D-chromatography, was avoided by using the MALDI method as quasi chromatographic separation KW - Liquid adsorption chromatography KW - Matrix-assisted laser desorption KW - Ionization mass spectrometry KW - Coupling methods KW - MALDI PY - 2000 DO - https://doi.org/10.1080/10236660008034644 SN - 1023-666X SN - 1563-5341 VL - 5 SP - 549 EP - 562 PB - Gordon and Breach Publ. CY - Amsterdam AN - OPUS4-2168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidner, Steffen A1 - Just, Ulrich A1 - Wittke, Wolfgang A1 - Rittig, F. A1 - Gruber, F. A1 - Friedrich, Jörg Florian T1 - Analysis of modified polyamide 6.6 using coupled liquid chromatography and MALDI-TOF-mass spectrometry KW - MALDI-TOF-MS KW - Liquid chromatography KW - Coupling methods PY - 2004 SN - 0168-1176 SN - 0020-7381 SN - 1387-3806 SN - 1873-2798 VL - 238 IS - 3 SP - 235 EP - 244 PB - Elsevier CY - Amsterdam AN - OPUS4-6966 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krüger, Ralph-Peter A1 - Heinemann, M. A1 - Falkenhagen, Jana A1 - Hartmann, A. A1 - Friedrich, Jörg Florian A1 - Fritz, H.-G. ED - Fritz, H. ED - Eisenbach, C. T1 - Charakterisierung biologisch abbaubarer Homo- und Copolyester / Characterisation of biodegradable Homo- and Copolyesters T2 - 19. Stuttgarter Kunststoff-Kolloquium 2005 CY - Stuttgart, Deutschland DA - 2005-03-09 KW - MALDI-TOF-MS KW - Bioabbaubare Polyester KW - Flüssigchromatographie KW - Methodenkopplung KW - Biodegradable polyesters KW - Liquid chromatography KW - Coupling of analytical methods PY - 2005 SN - 3-00-015246-6 SP - 5/P1-1 - 5/P1-9 PB - IKT CY - Stuttgart AN - OPUS4-11767 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wettmarshausen, Sascha A1 - Friedrich, Jörg Florian A1 - Meyer-Plath, Asmus A1 - Kalinka, Gerhard A1 - Hidde, Gundula A1 - Weidner, Steffen T1 - Coating of carbon fibers with adhesion-promoting thin poly(acrylic acid) and poly(hydroxyethylmethacrylate) layers using electrospray ionization N2 - Thin coatings of poly(acrylic acid) (PAA) and poly(hydroxyethylmethacrylate) (PHEMA) were deposited onto carbon fibers by means of the electrospray ionization (ESI) technique in ambient air. These high-molecular weight polymer layers were used as adhesion promoters in carbon fiber–epoxy resin composites. Within the ESI process, the carbon fibers were completely enwrapped with polymer in the upper 10 plies of a carbon fiber roving. As identified with scanning electron microscopy also shadowed fibers in a bundle as well as backsides of fiber rovings were pinhole-free coated with polymers (‘electrophoretic effect'). Under the conditions used, the layers have a granular structure. Residual solvent was absent in the deposit. PAA and PHEMA films did not show any changes in composition and structure in comparison with the original polymers as analyzed by X-ray photo-electron spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Single-fiber pullout tests of coated fibers embedded in epoxy resin showed significantly increased interfacial shear strength. It is assumed that chemical bonds between carbon fiber poly(acrylic acid) and epoxy resin contribute significantly to the improved interactions. KW - Adhesion promotion KW - Thin polymer layers KW - Electrospray ionization (ESI) KW - Carbon fiber–epoxy resin laminates KW - Layer topography PY - 2015 DO - https://doi.org/10.1080/01694243.2015.1040980 SN - 0169-4243 SN - 1568-5616 VL - 29 IS - 15 SP - 1628 EP - 1650 PB - VNU Science Press CY - Utrecht AN - OPUS4-34564 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -