Dokument-ID Dokumenttyp Autoren/innen Persönliche Herausgeber/innen Haupttitel Abstract Auflage Verlagsort Verlag Herausgeber (Institution) Erscheinungsjahr Titel des übergeordneten Werkes Jahrgang/Band ISBN Veranstaltung Veranstaltungsort Beginndatum der Veranstaltung Enddatum der Veranstaltung Ausgabe/Heft Erste Seite Letzte Seite URN DOI Lizenz Datum der Freischaltung OPUS4-11278 Zeitschriftenartikel Weidner, Steffen; Kühn, Gerhard; Just, Ulrich Characterization of oligomers in poly(ethylene terephthalate) by matrix-assisted laser desorption/ionization mass spectrometry Chichester Wiley 1995 Rapid communications in mass spectrometry 9 697 702 2016-02-19 OPUS4-7014 Beitrag zu einem Tagungsband Friedrich, Jörg Florian; Wigant, L.; Unger, Wolfgang; Lippitz, Andreas; Weidner, Steffen; Kühn, Gerhard; Geng, Sh.; Erdmann, J.; Gorsler, H.-V. Plasmavorbehandlungen von Polymeroberflächen Freiberg Forschungsinstitut für Leder- und Kunstledertechnologie, TU Bergakademie Freiberg 1995 2. Freiberger Polymertag : 30. Mai 1995 / Forschungsinstitut für Leder- und Kunstledertechnologie, Aninstitut der TU Bergakademie Freiberg 2. Freiberger Polymertag Freiberg 1995-05-30 17 Seiten 2016-02-19 OPUS4-11905 Beitrag zu einem Tagungsband Weidner, Steffen; Kühn, Gerhard; Just, Ulrich; Werthmann, Barbara; Decker, Renate; Schwarz, Bärbel; Borowski, Renate MALDI/MS - A New Technique in Characterizing Chemical Heterogeneity of Degradation Products of Poly(Ethylene Terephthalate)s Milford, Mass. Waters Chromatography Division 1996 International GPC Symposium '96 International GPC Symposium '96 San Diego, CA, USA 1996-09-08 1996-09-11 632 651 2016-02-19 OPUS4-7004 Zeitschriftenartikel Weidner, Steffen; Kühn, Gerhard; Friedrich, Jörg Florian; Unger, Wolfgang; Lippitz, Andreas Plasmaoxidative Degradation of Polymers Studied by Matrix-assisted Laser Desorption/Ionization Mass Spectrometry Chichester Wiley 1996 Rapid communications in mass spectrometry 10 727 732 2016-02-19 OPUS4-11347 Zeitschriftenartikel Kühn, Gerhard; Weidner, Steffen; Just, Ulrich; Hohner, G. Characterization of technical waxes - Comparison of chromatographic techniques and matrix-assisted laser-desorption/ionization mass spectrometry Technical waxes and paraffins were investigated using supercritical fluid chromatography (SFC), matrix-assisted laser-desorption/ionization mass spectrometry (MALDI-MS) and size-exclusion chromatography (SEC). SEC enables the simultaneous determination of molecular masses up to high values and molecular mass distributions. The resolution of homologous species, however, is poor. In this respect the use of SFC is advantageous. Proper resolution of homologues may be provided up to Mr~1200 without great difficulty. To compare these chromatographic results MALDI-MS was applied for the determination of molecular masses and mass distributions in technical waxes for the first time. Using reflectron mode excellent MALDI mass spectra could be achieved in the molecular mass range up to 1000 Da. The mean values of the molecular masses calculated by MALDI-MS were in sufficient agreement with those of SFC. In the linear mode of MALDI-MS molecular masses could be determined to nearly 3000 Da. Beyond this mass range SEC still remains the method of choice. Advantages and difficulties of the used methods are discussed in this paper. Amsterdam Elsevier 1996 Journal of chromatography A 732 1 111 117 10.1016/0021-9673(95)01255-9 2016-02-19 OPUS4-11095 Zeitschriftenartikel Weidner, Steffen; Holländer, A.; Kühn, Gerhard Matrix-assisted Laser Desorption/Ionization Mass Spectrometry of C36- Alkane degradated by Vacuum Ultraviolet Radiation Chichester Wiley 1997 Rapid communications in mass spectrometry 11 447 450 2016-02-19 OPUS4-7286 Beitrag zu einem Tagungsband Friedrich, Jörg Florian; Schulz, Eckhard; Weidner, Steffen; Kühn, Gerhard Improvement in Mechanical Strength of Fibre Polymer Composites by Fibre Pretreatment in Low-Pressure Plasmas Frankfurt am Main Messe Frankfurt 1997 Techtextil-Symposium '97 Vortragsbände des 8. Internationalen Techtextil-Symposiums 1997 Frankfurt am Main, Deutschland 1997-05-12 1997-05-14 1(?) 16(?) 2016-02-19 OPUS4-7287 Beitrag zu einem Tagungsband Friedrich, Jörg Florian; Schulz, Eckhard; Weidner, Steffen; Kühn, Gerhard Verbesserungen der mechanischen Festigkeiten von Faser-Polymer-Verbundwerkstoffen durch Vorbehandlung der Fasern im Niederdruckplasma Frankfurt am Main Messe Frankfurt 1997 Techtextil-Symposium '97 8 Vortragsbände des 8. Internationalen Techtextil-Symposiums 1997 Frankfurt am Main, Deutschland 1997-05-12 1997-05-14 1(?) 16(?) 2016-02-19 OPUS4-6994 Beitrag zu einem Tagungsband Friedrich, Jörg Florian; Unger, Wolfgang; Lippitz, Andreas; Koprinarov, Ivaylo; Weidner, Steffen; Kühn, Gerhard Schindel-Bidinelli, E. Umweltfreundliches Metallisieren von Kunststoffen durch Plasmavorbehandlung in einem geschlossenen Reaktor Rorbas SWIBOTECH 1997 Kleben : Grundlagen, Technologie, Anwendung Swissbonding 97 ; 11. Internationales Symposium Klebtechnik und Umwelt ; 11th International Symposium Bonding and Sealing Technology Rapperswil, Schweiz 1997-05-26 1997-05-28 1(?) 3(?) 2016-02-19 OPUS4-6995 Beitrag zu einem Tagungsband Friedrich, Jörg Florian; Unger, Wolfgang; Lippitz, Andreas; Koprinarov, Ivaylo; Weidner, Steffen; Kühn, Gerhard Nowack, H. Wechselwirkungen zwischen plasmamodifizierten Polymeroberflächen und Metallen Mülheim Print-Service 1997 Plasmatec '97 5 5. Internationale Fachtagung - ND-Plasma-Technologie Duisburg, Deutschland 1997-09-22 1997-09-23 1(?) 17(?) 2016-02-19 OPUS4-6997 Beitrag zu einem Sammelband Weidner, Steffen; Kühn, Gerhard; Roessner, D.; Friedrich, Jörg Florian; Unger, Wolfgang; Lippitz, Andreas Olefjord, I.; Nyborg, L.; Briggs, D. Changes in molecular weight distribution of polymers by plasma treatment Chichester Wiley 1997 ECASIA 97 0-471-97827-2 7th European Conference on Applications of Surface and Interface Analysis Göteborg, Sweden 1997-06-16 1997-06-20 795 799 2016-02-19 OPUS4-11357 Zeitschriftenartikel Weidner, Steffen; Kühn, Gerhard; Werthmann, Barbara; Schröder, Hartmut; Just, Ulrich; Borowski, Renate; Decker, Renate; Schwarz, Bärbel; Schmücking, I.; Seifert, Ingetraut A new approach of characterizing the hydrolytic degradation of poly(ethylene terephthalate) by MALDI-MS The hydrolytic degradation of technical poly(ethylene terephthalate) (PET) was investigated by means of different methods such as size-exclusion chromatography (SEC), viscometry, light-scattering, thin-layer chromatography, end-group titration, and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The long-term degradation was simulated by exposing PET filament yarns to aqueous neutral conditions at 90°C for up to 18 weeks. By means of MALDI-MS and thin-layer chromatography, the formation of different oligomers was obtained during polymer degradation. As expected, an ester scission process was found generating acid terminated oligomers (H-[GT]m-OH) and T-[GT]m-OH and ethylene glycol terminated oligomers (H-[GT]m-G), where G is an ethylene glycol unit and T is a terephthalic acid unit. Additionally, the scission of the ester bonds during the chemical treatment led to a strong decrease in the number of cyclic oligomers ([GT]m). The occurrence of di-acid terminated species demonstrated a high degree of degradation. Hoboken, NJ Wiley 1997 Journal of polymer science A, polymer chemistry 35 11 2183 2192 10.1002/(SICI)1099-0518(199708)35:11<2183::AID-POLA9>3.0.CO;2-Z 2016-02-19 OPUS4-6987 Beitrag zu einem Sammelband Friedrich, Jörg Florian; Unger, Wolfgang; Lippitz, Andreas; Koprinarov, Ivaylo; Kühn, Gerhard; Weidner, Steffen; Vogel, Lydia Mittal, K. Plasma Pretreatment of Polymer Surfaces - Relevance to Adhesion of Metals Utrecht VSP 1998 Metallized plastics 5 & 6 90-6764-290-8 5th Symposium on Metallized Plastics ; 6th Symposium on Metallized Plastics Los Angeles, CA, USA 1996-05-05 1996-05-09 271 293 2016-02-19 OPUS4-6988 Zeitschriftenartikel Weidner, Steffen; Kühn, Gerhard; Friedrich, Jörg Florian Infrared-Matrix-assisted Laser Desorption/Ionization and Infrared-Laser Desorption/Ionization Investigations of Synthetic Polymers Chichester Wiley 1998 Rapid communications in mass spectrometry 12 1373 1381 2016-02-19 OPUS4-6989 Zeitschriftenartikel Weidner, Steffen; Kühn, Gerhard; Decker, Renate; Roessner, D.; Friedrich, Jörg Florian Influence of Plasma Treatment on the Molar Mass of Poly(ethylene terephthalate) Investigated by Different Chromatographic and Spectroscopic Methods 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 Hoboken, NJ Wiley 1998 Journal of polymer science A, polymer chemistry 36 10 1639 1648 10.1002/(SICI)1099-0518(19980730)36:10<1639::AID-POLA17>3.0.CO;2-H 2016-02-19 OPUS4-6999 Zeitschriftenartikel Friedrich, Jörg Florian; Unger, Wolfgang; Lippitz, Andreas; Geng, Sh.; Koprinarov, Ivaylo; Kühn, Gerhard; Weidner, Steffen Modelling plasma-induced reactions on polymer surfaces using aliphatic self-assembling and LB layers Lausanne Elsevier Science 1998 Surface and coatings technology 98 1132 1141 2016-02-19 OPUS4-6981 Zeitschriftenartikel Friedrich, Jörg Florian; Unger, Wolfgang; Lippitz, Andreas; Koprinarov, Ivaylo; Kühn, Gerhard; Weidner, Steffen; Vogel, Lydia Chemical reactions at polymer surfaces interacting with a gas plasma or with metal atoms - their relevance to adhesion 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. Lausanne Elsevier Science 1999 Surface and coatings technology 116-119 772 782 10.1016/S0257-8972(99)00229-7 2016-02-19 OPUS4-6983 Zeitschriftenartikel Kühn, Gerhard; Weidner, Steffen; Decker, Renate; Ghode, Archana; Friedrich, Jörg Florian Selective surface functionalization of polyolefins by plasma treatment followed by chemical reduction Polymer surfaces can be finished with functional groups upon exposure to a plasma. Species of the plasma gas are attached at surface carbon atoms, forming functional groups of different composition. To produce a modified polymer surface with a high density and homogeneity of hydroxyl groups only, the oxygen-plasma-formed oxygen functional groups were chemically reduced by diborane and LiAlH4 with yields of 10 to 11 OH groups per 100 carbon atoms in the 3 to 5 nm near-surface layer as detected by X-ray photoelectron spectroscopy (XPS). The identification of hydroxyl groups was performed by means of attenuated total reflectance–Fourier transform infrared spectroscopy and XPS. Lausanne Elsevier Science 1999 Surface and coatings technology 116-119 796 801 10.1016/S0257-8972(99)00232-7 2016-02-19 OPUS4-6975 Beitrag zu einem Sammelband Kühn, Gerhard; Ghode, Archana; Weidner, Steffen; Retzko, Iris; Unger, Wolfgang; Friedrich, Jörg Florian Mittal, K. L. Chemically well-defined surface functionalization of polyethylene and polypropylene by pulsed plasma modification followed by grafting of molecules Utrecht VSP 2000 Polymer surface modification (volume 2) 2 90-6764-327-0 2nd International Symposium on Polymer Surface Modification: Relevance to Adhesion Newark, NJ, USA 1999-05-24 1999-05-26 45 64 2016-02-19 OPUS4-6979 Beitrag zu einem Sammelband Friedrich, Jörg Florian; Unger, Wolfgang; Lippitz, Andreas; Giebler, Rainer; Koprinarov, Ivaylo; Weidner, Steffen; Kühn, Gerhard Mittal, K. L. Significance of interfacial redox reactions and formation of metal-organic complexes for the adhesion of metals on pristine and plasma-treated polymers Utrecht VSP 2000 Polymer surface modification (volume 2) 2 90-6764-327-0 137 171 2016-02-19