TY - CONF A1 - Just, Ulrich A1 - Weidner, Steffen A1 - Wittke, Wolfgang A1 - Friedrich, Jörg Florian A1 - Rittig, F. A1 - Gruber, F. T1 - 2D-Characterization of Polyamides using Chromatography and MALDI-TOF-MS T2 - Waters International GPC 2003 and ISPAC-16-Symposium CY - Baltimore, MD, USA DA - 2003-06-09 PY - 2003 AN - OPUS4-2631 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 - Weidner, Steffen A1 - Kühn, Gerhard A1 - Roessner, D. A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Lippitz, Andreas ED - Olefjord, I. ED - Nyborg, L. ED - Briggs, D. T1 - Changes in molecular weight distribution of polymers by plasma treatment 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 - 795 EP - 799 PB - Wiley CY - Chichester AN - OPUS4-6997 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 - Weidner, Steffen A1 - Geng, Sh. A1 - Wigant, L. A1 - Wöll, Ch. A1 - Erdmann, J. A1 - Gorsler, H.-V. T1 - Characterization of plasma-modified organic surfaces by electron spectroscopy, SEIRA, and MALDI-TOF-MS T2 - 6th European Conference on Applications of Surface and Interface Analysis CY - Montreux, Switzerland DA - 1995-10-09 PY - 1995 SP - TC 11 PB - Wiley CY - Chichester AN - OPUS4-7001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Koprinarov, Ivaylo A1 - Kühn, Gerhard A1 - Weidner, Steffen A1 - Vogel, Lydia T1 - Chemical reactions at polymer surfaces interacting with a gas plasma or with metal atoms - their relevance to adhesion N2 - The chemical and morphological stabilities of polymer segments in the near-surface layer were investigated by spectroscopic methods such as X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure spectroscopy. Model studies were undertaken with Langmuir–Blodgett films, self-assembled monolayers and oligomer films. For thin polymer layers (30 to 500 nm), the changes in molecular-weight distributions of some polymers were investigated systematically by size exclusion chromatography, matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry and thermal-field flow fractionation for oxygen- and helium-plasma exposures. The polymer surfaces were found to be relatively stable at exposure to an oxygen low-pressure plasma up to ca. 2 s. This is important information to get maximum adhesion to metals in composites. In correlation to their redox potentials, potassium, aluminium and chromium react with oxygen functional groups at the polymer/metal interface. In a dedicated study, chromium was found to attack aromatic rings and form different reaction products. PY - 1999 U6 - https://doi.org/10.1016/S0257-8972(99)00229-7 SN - 0257-8972 VL - 116-119 SP - 772 EP - 782 PB - Elsevier Science CY - Lausanne AN - OPUS4-6981 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 - 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 U6 - 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 - 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 - JOUR A1 - Kona, Balakantha Rao A1 - Weidner, Steffen A1 - Friedrich, Jörg Florian T1 - Epoxidation of Polydienes Investigated by MALDI-TOF Mass Spectrometry and GPC-MALDI Coupling N2 - Polybutadienes (PB) and polyisoprenes (PI) with various molecular weights and polydispersities were epoxidized applying two different synthetic routes. The degree of epoxidation was determined by means of matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). It has been found that the degree of functionalization of polybutadiene is generally lower than that for polyisoprenes. Additionally, PB shows lower degrees of epoxidation at higher masses, whereas the level of functionalization of PI was unaffected by the molar mass. Coupling of gel permeation chromatography (GPC) with MALDI-TOF mass spectrometry was successfully used for the investigation of epoxidized polymers with higher masses. Using mass spectra of single fractions, the degree of epoxidation could be determined and applied for a calibration of GPC. PY - 2005 U6 - https://doi.org/10.1080/10236660490935736 SN - 1023-666X SN - 1563-5341 VL - 10 IS - 1-2 SP - 85 EP - 109 PB - Gordon and Breach Publ. CY - Amsterdam AN - OPUS4-11860 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Jörg Florian A1 - Schulz, Eckhard A1 - Weidner, Steffen A1 - Kühn, Gerhard T1 - Improvement in Mechanical Strength of Fibre Polymer Composites by Fibre Pretreatment in Low-Pressure Plasmas T2 - Vortragsbände des 8. Internationalen Techtextil-Symposiums 1997 CY - Frankfurt am Main, Deutschland DA - 1997-05-12 PY - 1997 SP - 1(?) EP - 16(?) PB - Messe Frankfurt CY - Frankfurt am Main AN - OPUS4-7286 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mühlhan, C. A1 - Weidner, Steffen A1 - Friedrich, Jörg Florian A1 - Nowack, H. T1 - Improvement of bonding properties of polypropylene by low-pressure plasma treatment PY - 1999 SN - 0257-8972 VL - 116-119 SP - 783 EP - 787 PB - Elsevier Science CY - Lausanne AN - OPUS4-6982 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 U6 - 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 - Weidner, Steffen A1 - Kühn, Gerhard A1 - Friedrich, Jörg Florian T1 - Infrared-Matrix-assisted Laser Desorption/Ionization and Infrared-Laser Desorption/Ionization Investigations of Synthetic Polymers PY - 1998 SN - 0951-4198 SN - 1097-0231 VL - 12 SP - 1373 EP - 1381 PB - Wiley CY - Chichester AN - OPUS4-6988 LA - eng 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 U6 - 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 - CONF A1 - Weidner, Steffen A1 - Falkenhagen, Jana A1 - Friedrich, Jörg Florian A1 - Krüger, Ralph-Peter A1 - Schulz, Günter A1 - Much, Helmut T1 - Liquid Adsorption Chromatography near Critical Conditions of Adsorption coupled with Matrix-assisted Laser/Ionization Mass Spectrometry T2 - 47th ASMS Conference on Mass Spectrometry and Allied Topics CY - Dallas, TX, USA DA - 1999-06-13 PY - 1999 CY - Dallas, Tex AN - OPUS4-2165 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Geng, Sh. A1 - Koprinarov, Ivaylo A1 - Kühn, Gerhard A1 - Weidner, Steffen T1 - Modelling plasma-induced reactions on polymer surfaces using aliphatic self-assembling and LB layers PY - 1998 SN - 0257-8972 VL - 98 SP - 1132 EP - 1141 PB - Elsevier Science CY - Lausanne AN - OPUS4-6999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Friedrich, Jörg Florian A1 - Kühn, Gerhard A1 - Mix, Renate A1 - Retzko, Iris A1 - Gerstung, Vanessa A1 - Weidner, Steffen A1 - Schulze, Rolf-Dieter A1 - Unger, Wolfgang ED - Mittal, K. L. T1 - Plasma polymer adhesion promoters for metal-polymer systems T2 - 2nd International Symposium on Polyimides and Other High Temperature Polymers: Synthesis, Characterization and Applications CY - Newark, NJ, USA DA - 2001-12-03 KW - r.f. pulsed plasma KW - Plasma polymers with functional groups KW - Copolymers KW - Adhesion promoting interlayers KW - Metal-polymer systems PY - 2003 SN - 90-6764-378-5 VL - 2 SP - 359 EP - 388 PB - VSP CY - Utrecht AN - OPUS4-6967 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Koprinarov, Ivaylo A1 - Kühn, Gerhard A1 - Weidner, Steffen A1 - Vogel, Lydia ED - Mittal, K. T1 - Plasma Pretreatment of Polymer Surfaces - Relevance to Adhesion of Metals T2 - 5th Symposium on Metallized Plastics ; 6th Symposium on Metallized Plastics CY - Los Angeles, CA, USA DA - 1996-05-05 PY - 1998 SN - 90-6764-290-8 SP - 271 EP - 293 PB - VSP CY - Utrecht AN - OPUS4-6987 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidner, Steffen A1 - Kühn, Gerhard A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Lippitz, Andreas T1 - Plasmaoxidative Degradation of Polymers Studied by Matrix-assisted Laser Desorption/Ionization Mass Spectrometry PY - 1996 SN - 0951-4198 SN - 1097-0231 VL - 10 SP - 727 EP - 732 PB - Wiley CY - Chichester AN - OPUS4-7004 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Jörg Florian A1 - Wigant, L. A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Weidner, Steffen A1 - Kühn, Gerhard A1 - Geng, Sh. A1 - Erdmann, J. A1 - Gorsler, H.-V. T1 - Plasmavorbehandlungen von Polymeroberflächen T2 - 2. Freiberger Polymertag CY - Freiberg DA - 1995-05-30 PY - 1995 SP - 17 Seiten CY - Freiberg AN - OPUS4-7014 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -