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 - CONF A1 - Weidner, Steffen T1 - Liquid Adsorption Chromatography near Critical Conditions of Adsorption coupled with Matrix-assisted Laser Desorption / ionization Mass Spectrometry T2 - 47th Conference of The American Society of Mass Spectrometry CY - Dallas, TX, USA DA - 1999-06-11 PY - 1999 AN - OPUS4-2240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, Jörg Florian A1 - Ghode, Archana A1 - Kühn, Gerhard A1 - Weidner, Steffen A1 - Geng, Shiming A1 - Retzko, Iris A1 - Unger, Wolfgang A1 - Lippitz, Andreas ED - Schindel-Bidinelli, E. T1 - Polymeroberflächenfunktionalisierungen im gepulsten Plasma mit nachfolgender chemischer Behandlung T2 - 14. Internationales Symposium Swissbonding ; 14. Internationaler Kongreß Swiss Bonding ; 14th Swiss Bonding 00 CY - Rapperswil, Schweiz DA - 2000-05-16 PY - 2000 SP - 31 EP - 44 PB - SWIBOTECH GmbH CY - Bülach AN - OPUS4-6980 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weidner, Steffen T1 - Mechanism of homogeneously catalyzed polymerization of liquid-crystalline sidegroup monomers investigated by means of MALDI-TOF-MS (No. 433) T2 - 219th ACS National Meeting CY - San Francisco, CA, USA DA - 2000-03-26 PY - 2000 AN - OPUS4-11314 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 - Gross, J.H. A1 - Weidner, Steffen T1 - Influence of Electric Field Strength and Emitter Temperature on Field Desorption Mass Spectra of Polyethylene Oligomers N2 - The influence of electric field strength and emitter temperature on dehydrogenation and C–C cleavage in field desorption (FD) mass spectrometry of polyethylene (PE) oligomers of average molecular weights ranging from 500 to 2000 is examined. Low mass oligomers yield molecular weight (MW) distributions that are basically in accordance with results from gel-permeation chromatography. For these materials, dehydrogenation can be greatly reduced by reduction of the emitter potential. Furthermore, the influence of emitter potential on MW distributions indicates the occurrence of field-induced C–C cleavages. Reliable MW distributions are more difficult to obtain from higher mass oligomers by FD-MS because of the need for higher field strength and higher emitter temperatures to effect their desorption/ionization. Experiments reveal that the application of FD-MS to PE oligomers is limited not only by field-induced but also by thermally-induced fragmentations. Even then, FD mass spectra contain valuable information on mass range and homogeneity of PE samples up to about m/z 3600. PY - 2000 DO - https://doi.org/10.1255/ejms.300 SN - 1469-0667 SN - 1356-1049 SN - 1365-0718 IS - 6 SP - 11 EP - 17 PB - IM Publications CY - Chichester AN - OPUS4-11098 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 - Giebler, Rainer A1 - Koprinarov, Ivaylo A1 - Weidner, Steffen A1 - Kühn, Gerhard ED - Mittal, K. L. T1 - Significance of interfacial redox reactions and formation of metal-organic complexes for the adhesion of metals on pristine and plasma-treated polymers KW - Oxygen low-pressure plasma treatment of polymers KW - Metal-polymer interactions KW - Peel strength PY - 2000 SN - 90-6764-327-0 VL - 2 SP - 137 EP - 171 PB - VSP CY - Utrecht AN - OPUS4-6979 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 - 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 - GEN A1 - Falkenhagen, Jana A1 - Krüger, Ralph-Peter A1 - Much, Helmut A1 - Schulz, Günter A1 - Weidner, Steffen ED - Grellmann, W. T1 - Characterization and identification of new polymer structures by optimization and coupling of HPLC and MALDI-TOF-MS T2 - Polymerwerkstoffe 2000 CY - Halle (Saale), Germany DA - 2000-09-25 PY - 2000 SN - 3-86010-605-8 PB - Martin-Luther-Univ. CY - Halle AN - OPUS4-2250 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weidner, Steffen T1 - Neue Wege zur analytischen Charakterisierung komplexer Polymersysteme T2 - Berliner Polymerentage 2000 CY - Berlin, Germany DA - 2000-10-09 PY - 2000 AN - OPUS4-11134 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weidner, Steffen T1 - MALDI-TOF-MS of low-molar mass polyethylene and waxes T2 - 49th Conference of the American Society of Mass Spectrometry CY - Chicago, IL, USA DA - 2001-05-25 PY - 2001 AN - OPUS4-11302 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Falkenhagen, Jana A1 - Krüger, Ralph-Peter A1 - Schulz, Günter A1 - Weidner, Steffen T1 - Polymer characterization by LC / MALDI-MS coupling T2 - Bayreuther Polymer Symposium 2001 CY - Bayreuth, Germany DA - 2001-09-16 PY - 2001 CY - Bayreuth AN - OPUS4-2256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Czichocki, G. A1 - Fiedler, H. A1 - Haage, K. A1 - Much, Helmut A1 - Weidner, Steffen T1 - Characterization of alkyl polyglycosides by both reversed-phase and normal-phase modes of high-performance liquid chromatography N2 - Alkyl polyglycosides today represent the most important sugar surfactant. Nonionic sugar surfactants produced via different synthetic routes are mixtures of alkyl homologues, oligomers, anomers and isomers. Alkyl homologues and oligomers of alkyl mono- and diglucosides were separated by reversed-phase high-performance liquid chromatography (HPLC) with methanol–water as the mobile phase using a gradient elution. The gradient was optimized in respect to a simultaneous separation of alkyl glycosides according to their alkyl chain length and alkyl polyoxyethylene glucosides with regard to their length of the polyoxyethylene spacer. The separation of alkyl glycosides into ?- and ?-anomers was carried out by normal-phase HPLC with isooctane–ethyl acetate (60:40, v/v)–2-propanol in the gradient mode. Light scattering detection was used. Matrix-assisted laser desorption ionization time-of-flight mass spectra of alkyl glucosides and dodecyl glucosides with oxyethylene spacer groups are presented. PY - 2002 DO - https://doi.org/10.1016/S0021-9673(01)01459-5 SN - 0021-9673 VL - 943 IS - 2 SP - 241 EP - 250 PB - Elsevier CY - Amsterdam AN - OPUS4-11099 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weidner, Steffen T1 - MALDI von geregelten und ungeregelten Polyamiden nach kritischer Chromatographie T2 - VII. Anwendertreffen MALDI-TOF-MS zur Charakterisierung von synthetischen Polymeren CY - Berlin, Germany DA - 2002-05-14 PY - 2002 AN - OPUS4-11136 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cappella, Brunero A1 - Sturm, Heinz A1 - Weidner, Steffen T1 - Breaking polymer chains by dynamic plowing lithography N2 - The adhesion of poly(methyl methacrylate) (PMMA) and polystyrene (PS) films, whose surface has been previously structured by dynamic plowing lithography (DPL), has been measured by means of force–displacement curves. The different adhesion of modified and unmodified PS leads to the assumption that polymer chains are broken during DPL. After measuring the energy dissipated by the tip during DPL, in order to check that the transferred energy is sufficient to break covalent bonds, the polymer chain scission caused by the lithographic process has been definitely confirmed by size exclusion chromatography measurements of the lithographed films. KW - AFM KW - Nanolithography KW - Chain scission PY - 2002 DO - https://doi.org/10.1016/S0032-3861(02)00285-9 SN - 0032-3861 SN - 1873-2291 VL - 43 IS - 16 SP - 4461 EP - 4466 PB - Springer CY - Berlin AN - OPUS4-1608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Falkenhagen, Jana A1 - Krüger, Ralph-Peter A1 - Schulz, Günter A1 - Weidner, Steffen T1 - Polymer Characterization by LC / MALDI-MS Coupling T2 - Vortragstagung "Funktionspolymere für Systemlösungen" CY - Darmstadt, Germany DA - 2002-03-18 PY - 2002 AN - OPUS4-1805 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weidner, Steffen T1 - LC-MALDI Coupling for "quantitative" Analysis of Polymers T2 - NIST CY - Gaithersburg, MD, USA DA - 2002-11-06 PY - 2002 AN - OPUS4-11138 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 - Weidner, Steffen T1 - Rezension: Kompakte Zusammenfassung - MALDI-TOF Mass Spectrometry of Synthetic Polymers. Von H. Pasch, W. Schrepp. Springer, Heidelberg 2003, 298 Seiten. geb., 79,95 Euro. ISBN 3-540-44259-6 PY - 2003 DO - https://doi.org/10.1002/nadc.20030511123 SN - 1439-9598 SN - 1521-3854 VL - 51 IS - 11 SP - 1173 PB - Wiley-VCH CY - Weinheim AN - OPUS4-4678 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -