TY - THES A1 - Joshi, Ranjit Sharad T1 - Polymer surface modification using novel underwater plasma (UWP) technique N2 - Plasmachemische Methoden sind geeignet, um chemisch inerte Polyolefinoberflächen zu funktionalisieren. Meist entsteht jedoch dabei eine große Vielfalt verschiedener funktioneller Gruppen. Für Pfropfreaktionen an diesen Gruppen, aber auch für höherwertige Anwendungen ist die Existenz einer hochdicht mit einer einzigen Sorte funktioneller Gruppen versehenen Polymeroberfläche Voraussetzung. Dementsprechend sollte in dieser Arbeit versucht werden, einen solch einen selektiven Funktionalisierungsprozeß zu entwickeln, der möglichst nur eine Art funktioneller Gruppe in hoher Konzentration liefert. Innerhalb mehrerer neuentwickelter selektiver Plasmaprozesse erschien das Unterwasserplasma (UWP) besonders aus technischer Sicht zur Lösung dieses Problems geeignet. Das UWP ist Quelle von Ionen, Elektronen, UV-Strahlung, Schockwellen, Radikalen, wie Hydroxyl-, sowie reaktiven Neutralmolekülen, wie Wasserstoffperoxid, Wasserstoff und Sauerstoff. Das UWP und die nahverwandte Glimmentladungselektrolyse (GDE) stellen interessante neue Methoden für die Polymeroberflächenmodifizierung dar. Die Polymeroberfläche wird durch Wirken von Elektrochemie, Naßchemie, Plasma- und Strahlenchemie sowie durch Schockwellen umgestaltet. Das UWP ist naheliegenderweise besonders zur Polymeroberflächenmodifizierung mit OH-Gruppen geeignet. Es ist wegen der Art der Erzeugung (Kapillarentladung und Schockwellenerzeugung) ein strömungsbestimmtes Plasma. Je nach Entladungsbedingungen hatten die OH-Gruppen einen Anteil von 25-40% von allen durch das Plasma eingeführten sauerstoffhaltigen Gruppen. Dieser Anteil reicht nicht aus, um von einem selektiven Plasma zu sprechen, ist aber deutlich höher als bei der Modifzierung im Sauerstoffniederdruckplasma, wo weniger als 10% aller O-Funktionalitäten OH-Gruppen sind. Die genaue Bestimmung der OH- Gruppenkonzentration erfordert deren Derivatisierung mit Trifluoressigsäureanhydrid (TFAA), um über die Fluorbestimmung mit Photoelektronenspektroskopie (XPS) diese Konzentration berechnen zu können. Im Unterschied zu der etablierten Niederdruckplasmatechnik moderiert die Wasserphase im UWP die hochenergetischen Spezies sehr schnell auf ein energetisch niedriges Niveau, was den Energieeintrag und die damit verbundenen Veränderungen im Polymer begrenzt. Intensive Oxidation, starker Abbau, Vernetzung und Radikalbildung im Polymer werden weitgehend zurückgedrängt. Möglicherweise dennoch entstehende Abbauprodukte werden durch die umgebende Wasserphase sofort aufgelöst. Die Produktpalette an funktionellen Gruppen auf der im UWP modifizierten Polypropylenfolie beschränkt sich auf C-O-Spezies mit einer Sauerstoffeinfachbindung und wenigen mit zwei Sauerstoffbindungen. Ein weiterer interessanter Gesichtspunkt ist, dass eine Vielfalt an chemischen Additiven zum UWP zumischbar ist, wodurch sich die Reaktionsrichtung beeinflussen lässt. Wasserstoffperoxid- und Katalysatorzugabe (Fe-ZSM5) sollten die Reaktivität des UWP beeinflussen, indem die Konzentration der für die OH-Funktionalisierung verantwortlich gemachten OH-Radikale als Produkte der homolytischen Wasserstoffperoxiddissoziation erhöht wird. Der Katalysator beschleunigte die Gleichgewichtseinstellung zwischen OH- Gruppenbildung durch Dissoziation und Rekombination, was sich vor allem in einer erhöhten Oxidationsrate widerspiegelte. Entsprechend den analytischen Möglichkeiten der XPS konnten als Schnellbestimmung lediglich die Summe aller C-O einfach gebundenen Spezies gemessen werden, wie C-OH, C-O-C oder Hydroperoxide. Diese „C-O-Selektivität“ betrug im UWP 47 C-O/100 O-Atome und konnte durch Mitwirkung des Katalysators (Fe-ZSM5) auf 81 C-O/100 O-Atome verbessert werden, was zunächst einen bemerkenswerten Fortschritt darstellte. Die TFAA-Dervatisierung ergab jedoch, daß der Anteil an OH-Gruppen innerhalb der C-O-Spezies nicht erhöht werden konnte. Eine andere Möglichkeit bestand in der Erzeugung von Carboxylgruppen an der Polypropylenoberfläche. Dazu wurden Essigsäure, Acryl-, Malein- und Itaconsäure als Modifikatoren bzw. Monomere für die Polymerbildung eingesetzt. Die erwartete bevorzugte Bildung von COOH-Gruppen an der Polymeroberfläche war jedoch niedrig bei Einsatz polymerbildender Säuren. Diese Tatsache war nicht weiter verwunderlich, weil die gebildeten COOH- enthaltenden Polymere wasserlöslich sind. Nur die durch das UWP fragmentierten Monomere konnten eine im Wasser nicht lösliche Polymerabscheidung ergeben, die aber nur noch einen gewissen Bruchteil der ursprünglichen COOH-Gruppen besaß. Essigsäure muss diesen Fragmentierungsweg gehen, wobei gehofft wurde, dass überlebende COOH- Spezies an der Polypropylenoberfläche die gewünschten Säuregruppen in der vernetzten Schicht bilden würden. Die XPS wurde zur Identifizierung und Konzentrationsbestimmung der COOH(R)-Spezies benutzt. Zur zweifelsfreien Konzentrationsbestimmung wurde die Gasphasenderivatisierung mit Trifluorethanol eingesetzt. Eine wesentlich höhere COOH Ausbeute ergab der Einsatz von Acrylsäure in der GDE. N2 - Plasma chemical methods are well suited for introducing functional groups to the surface of chemically inert polymers such as polyolefins. However, a broad variety of functional groups is often formed. Unfortunately, for further chemical processing such as grafting of molecules for advanced applications a highly dense and monotype functionalized polyolefin surface is needed. Therefore, the main task was to develop a selective surface functionalization process, which forms preferably one type of functional groups at the surface in high and variable concentration. Amongst the novel plasma methods, the under-water plasma process (UWP) is one of most attractive to solve the problem of monotype functionalization. Such plasma is an efficient source of ions, electrons, UV-radiation, high frequency shock waves, radicals such as hydroxyl radical and reactive neutral molecules such as hydrogen peroxide, hydrogen and oxygen. It was found that underwater plasma and the closely related glow discharge electrolysis are interesting new methods for polymer surface functionalization. An effective modification into the topmost surface chemistry of polymer layer was observed by the collective effect of wet-chemistry, electrochemistry, atmospheric gas discharges, irradiation, and shock waves. Underwater capillary discharge was seen more effective in -OH functionalization and was largely seen as a flow dominated process because of the shock wave turbulences. Using such water-based plasma a fraction of 25-40% of all O-functional groups was produced as OH-groups in comparison to <10% OH produced in the oxygen low- pressure plasma. The exact concentration of the OH functionality was studied by TFAA gas phase derivatization and measuring the respective fluorine concentration by photoelectron spectroscopy (XPS). In contrast to established gas phase glow discharge processes, the water phase absorbs and therefore limits the particle and radiation energy and thus the energy input into the polymer. Extensive oxidation, degradation, cross-linking and radical formation in the polymer is more limited than under gas plasma exposure because of the liquid water environment, which moderates high energetic plasma species. The variety of plasma produced species in the water phase is also much smaller because of the limited reaction possibilities of the plasma with water. The possibility to admix a broad variety of chemical additives makes underwater plasma additionally highly attractive for the chemist. At last, the water removes all low-molecular weight oxidized products formed by plasma-induced polymer degradation. Hydrogen peroxide and the catalyst (Fe-ZSM5) should influence or increase the equilibrium concentration of OH radicals in the underwater process. It was supposed that these radicals play the most important role for OH functionalization of polyolefin surfaces. Hydrogen peroxide was believed to be the most prominent precursor for OH group formation in the UWP. The catalyst should modulate the steady state of OH group formation and recombination, and thus accelerate the functionalization. This was confirmed by an increased oxidation rate. Owing to the detection limit of XPS the C-O bond selectivity was defined as clearly resolvable subpeak within the C1s signal assigned to C-OH, C-O-C and other singly C-O bonded species. This bondamounts 47 C-O bonds/100 O atoms with pure UWP system and enhances to a maximum of the 81 C-O bonds/100 O atoms using the Fe-ZSM5 catalyst system. Therefore, this method exhibits a great progress for a start. However, after TFAA derivatization the fraction of desired OH groups could not be significantly increased. In the continuation acetic acid, acrylic acid, maleic and itaconic acid were used as additive monomers. The chemical selectivity in -COOH bond formation using bi-carboxylic additives was seen inferior. Acetic acid is not a chemically polymerizing monomer but it could polymerize by monomer/molecular fragmentation and recombination to a cross linked layer. The other monomers form preferably water-soluble polymers on a preferred chemical way. Only the fragmented fraction of these monomers could form an insoluble coating by cross linking to substrate. The XPS analysis was used to track the alterations in COO- bond percentage on the PP surface. To identify the -COOH groups on substrate surface unambiguously, which have survived the plasma polymerization process, the gas phase derivatization with trifluoroethanol was performed. A much higher yield in COOH groups was achieved using the glow discharge electrolysis and acrylic acid. T3 - BAM Dissertationsreihe - 59 KW - hydrogen peroxide KW - Feton-like processes KW - hydroperoxyl radicals KW - Polymer surface modification KW - polymer surface chemistry KW - underwater plasma KW - capillary discharge KW - selective monofunctional surface KW - hydroxyl fictionalization PY - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-993 SN - 978-3-9813550-2-4 SN - 1613-4249 VL - 59 SP - 1 EP - 145 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-99 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Joshi, Ranjit A1 - Friedrich, Jörg Florian T1 - Unterwasserplasma zur Funktionalisierung oder Beschichtung von Polymeroberflächen T2 - 16. Neues Dresdner Vakuumtechnisches Kolloquium - Beschichtung, Modifizierung und Charakterisierung von Polymeroberflächen CY - Dresden, Deutschland DA - 2008-10-16 KW - Polymer-Oberflächenfunktionalisierung PY - 2008 SN - 978-3-9812550-0-3 SP - 44 EP - 52 AN - OPUS4-18315 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Mix, Renate A1 - Schulze, Rolf-Dieter A1 - Meyer-Plath, Asmus A1 - Joshi, Ranjit A1 - Wettmarshausen, Sascha T1 - New Plasma Techniques for Polymer Surface Modification with Monotype Functional Groups N2 - The production of chemically-defined plasma polymers and the introduction of monotype functional groups onto polymer surfaces are described. One method is to lower the energetic level of low-pressure plasmas. Pressure- and plasma-pulsed plasmas were successfully tested for the production of chemically-defined plasma polymers by increasing the monomer supply during the plasma-off period. Well-defined ultra-thin polymer films with regular structure were deposited from atmospheric plasmas by electrospray techniques. Post-plasma wet-chemical processing was also applied, as were gas/liquid-based aerosols and underwater plasmas. KW - Plasma KW - Polymer-Oberflächenfunktionalisierung KW - Macromolecular plasma KW - Monotype functional groups KW - Plasma bromination KW - Plasma treatment KW - Pressure-pulsed plasma KW - Underwater plasma PY - 2008 U6 - https://doi.org/10.1002/ppap.200700145 SN - 1612-8850 SN - 1612-8869 VL - 5 IS - 5 SP - 407 EP - 423 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-17742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Joshi, Ranjit A1 - Wagner, M.H. A1 - Friedrich, Jörg F. T1 - Polymer suface treatment studies for ester bond generation using solution plasma technique and its relevance to surface modification with carboxylic functionality T2 - 23th Symposium on Plasma Physics and Technology CY - Prague, Czech Republic DA - 2008-06-16 PY - 2008 AN - OPUS4-17750 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Joshi, Ranjit A1 - Meyer-Plath, Asmus A1 - Schulze, Rolf-Dieter A1 - Friedrich, Jörg F. T1 - Surface modification studies of polypropylene films using underwater capillary discharge T2 - 3rd International Congress on Cold Atmospheric Pressure Plasmas: Sources and Application CY - Ghent, Belgium DA - 2007-07-10 PY - 2007 AN - OPUS4-15047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Joshi, Ranjit A1 - Schulze, Rolf-Dieter A1 - Meyer-Plath, Asmus A1 - Friedrich, Jörg F. A1 - Wagner, M.H. T1 - Selective surface modification of polypropylene using underwater plasma technique or underwater capillary discharge T2 - PSE-2008 11th International Conference on Plasma Surface Engineering CY - Garmisch-Partenkirchen, Germany DA - 2008-09-15 PY - 2008 AN - OPUS4-18064 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Joshi, Ranjit A1 - Schulze, Rolf-Dieter A1 - Meyer-Plath, Asmus A1 - Friedrich, Jörg F. T1 - Selective surface functionalisation of polypropylene films using the underwater capillary discharge T2 - 18th International Symposium on Plasma Chemistry CY - Kyoto, Japan DA - 2007-08-26 PY - 2007 AN - OPUS4-15752 LA - deu 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 U6 - 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 - CONF A1 - Joshi, Ranjit A1 - Friedrich, Jörg F. T1 - Effects of H2O2 generated during underwater discharges and hydroperoxyl functionality (-O-OH) formed on the selective (-OH) hydroxyl functionalization of PP-surface using underwater plasma technique. T2 - 19th International Symposium on Plasma Chemistry (ISPC '19) CY - Bochum, Germany DA - 2009-07-26 PY - 2009 AN - OPUS4-19722 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Joshi, Ranjit A1 - Friedrich, Jörg Florian A1 - Wagner, M. T1 - Role of hydrogen peroxide in selective OH group functionalization of polypropylene surfaces using underwater capillary discharge N2 - Plasma chemical methods are well suited for introducing functional groups to the surfaces of chemically inert polymers such as polyolefins. However, a broad variety of functional groups are often formed. Unfortunately, for further chemical processing such as grafting of molecules for advanced applications a highly dense monotype functionalized polyolefin surface is needed. Therefore, the main task was to develop a selective surface functionalization process, which formed preferably only a single type of functional groups at the surface in high concentration. Amongst the novel plasma methods, the underwater plasma process (UWP) is one of most attractive options to solve the problem of monotype functionalization. Such plasma is an efficient source of ions, electrons, UV-radiation, high-frequency shock waves, radicals such as hydroxyl radical, and reactive neutral molecules such as hydrogen peroxide. In contrast to established gas phase glow discharge processes, the water phase limits the particle and radiation energies and thus the energy input into the polymer. By virtue of the liquid water environment, which moderates highly energetic plasma species, extensive oxidation, degradation, cross-linking and radical formation on the polymer are more limited as compared to gas plasma exposure. The variety of plasma produced species in the water phase is also much smaller because of the limited reaction possibilities of the plasma with water. The possibility to admix a broad variety of chemical additives makes underwater plasma even more attractive. Hydrogen peroxide and the catalyst (Fe-ZSM5) should influence and increase the equilibrium concentration of OH radicals in the underwater plasma process. It was found that these radicals played a very important role in OH functionalization of polyolefin surfaces. Hydrogen peroxide was identified to be the most prominent precursor for OH group formation in the UWP. The catalyst would affect the steady state of OH radical formation and its reaction with the substrate surface and thus accelerates the functionalization process. KW - Surface modification KW - Polymer functionalization KW - Underwater plasma KW - Capillary discharge KW - Hydroxyl functionalization KW - Hydrogen peroxide KW - Hydroperoxyl radicals KW - Heterogeneous catalysis KW - Fenton-like processes PY - 2011 U6 - https://doi.org/10.1163/016942410X520862 SN - 0169-4243 SN - 1568-5616 VL - 25 SP - 283 EP - 305 PB - VNU Science Press CY - Utrecht AN - OPUS4-22413 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Joshi, Ranjit A1 - Schulze, Rolf-Dieter A1 - Meyer-Plath, Asmus A1 - Wagner, M.H. A1 - Friedrich, Jörg Florian T1 - Selective surface modification of polypropylene using underwater plasma technique or underwater capillary discharge N2 - Among new types of plasma processes, the underwater plasma is one of the most attractive methods for functionalization of polymer surfaces. The interesting features of plasma solution system are that the material surfaces to be modified remain in contact with the plasma-moderated solution. The role of plasma-moderated liquids, allows the reach of the reactive species through solution onto the geometrically hindered sites. The UV radiation produced in plasma formation helps in generating additional excited, ionized, and dissociated molecules and species in the reaction solution. An interesting feature of the technique is its flexibility to use a wide variety of additives as or in solution system. This allows us to create a selective or monotype functionalization of material surfaces. Such system was studied for the selective hydroxyl functionalization of polypropylene surface. The oxidation of polymer surfaces and the introduction of O-containing functional groups by underwater plasma was found to exceed concentrations typically achieved in oxygen low-pressure gas discharge plasmas up-to two-folds (maximal 56 O/100 C). The fraction of OH groups among all O-containing moieties amounts from 25 to 40% in comparison to that in the gas plasma of about 10% OH groups. Addition of hydrogen peroxide into this same system increases the fraction of C—O bonds up to 75% (27-OH/100 O). A study was focused to optimize the role of hydrogen peroxide on the efficiency of oxidation and selectivity with chemical derivatization with respect to the formation of mono-sort hydroxyl functionalities, calculated using a chemical derivatization technique. KW - Capillary discharge KW - Functionalization of polymer KW - Modification surfaces KW - Underwater plasma KW - Surface modification KW - Polymer functionalization PY - 2009 U6 - https://doi.org/10.1002/ppap.200930601 SN - 1612-8850 SN - 1612-8869 VL - 6 IS - Suppl. 1 SP - 5218 EP - 5222 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-22772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Friedrich, Jörg Florian A1 - Meyer-Plath, Asmus A1 - Mix, Renate A1 - Schulze, Rolf-Dieter A1 - Joshi, Ranjit ED - Tachibana, K. ED - Takai, O. T1 - New plasmas for polymer surface functionalization 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 - 29A/a8, 1 EP - 4 PB - International Union of Pure and Applied Chemistry CY - Kyoto AN - OPUS4-20666 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mix, Renate A1 - Joshi, Ranjit A1 - Schulze, Rolf-Dieter A1 - Meyer-Plath, Asmus A1 - Friedrich, Jörg Florian ED - Tachibana, K. ED - Takai, O. T1 - Aerosol and underwater plasma for polymer surface functionalization 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 - 27P/80, 1 EP - 4 PB - International Union of Pure and Applied Chemistry CY - Kyoto AN - OPUS4-20667 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Joshi, Ranjit A1 - Schulze, Rolf-Dieter A1 - Meyer-Plath, Asmus A1 - Friedrich, Jörg Florian T1 - Selective surface modification of Poly(propylene) with OH and COOH groups using liquid-plasma systems N2 - Underwater plasma and glow discharge electrolysis are interesting new methods for polymer surface functionalization. The achievable content of O-containing functional groups exceeds that of oxygen glow discharge gas plasmas by a factor of two (up to ca. 56 O/100 C). The percentage of OH groups among all O-containing groups can reach 25 to 40%, whereas it is about 10% in the gas plasmas. Addition of hydrogen peroxide increases the fraction of OH groups to at most 70% (27 OH/100 C). The liquid plasma systems are also able to polymerize acrylic acid and deposit the polymer as very thin film on substrate surfaces or membranes, thereby retaining about 80% of all COOH functional groups (27 COOH/100 C). KW - Polymeroberflächen KW - Funktionelle Gruppen PY - 2008 U6 - https://doi.org/10.1002/ppap.200700175 SN - 1612-8850 SN - 1612-8869 VL - 5 IS - 7 SP - 695 EP - 707 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-18884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Joshi, Ranjit A1 - Friedrich, Jörg Florian A1 - Wagner, M.H. T1 - Study of carboxylic functionalization of polypropylene surface using the underwater plasma technique N2 - Non-equilibrium solution plasma treatment of polymer surfaces in water offers the possibility of more dense and selective polymer surface functionalization in comparison to the well-known and frequently used low-pressure oxygen plasma. Functional groups are introduced when the polymer surface contacts the plasma moderated solution especially water solutions. The emission of ions, electrons, energy-rich neutrals and complexes, produced by the ion avalanche are limited by quenching, with the aid of the ambient water phase. The UV-radiation produced in plasma formation also helps to moderate the reaction solution further by producing additional excited, ionized/dissociated molecules. Thus, monotype functional groups equipped polymer surfaces, preferably OH groups, originating from the dissociated water molecules, could be produced more selectively. An interesting feature of the technique is its flexibility to use a wide variety of additives in the water phase. Another way to modify polymer surfaces is the deposition of plasma polymers carrying functional groups as carboxylic groups used in this work. Acetic acid, acrylic acid, maleic and itaconic acid were used as additive monomers. Acetic acid is not a chemically polymerizing monomer but it could polymerize by monomer/molecular fragmentation and recombination to a cross linked layer. The other monomers form preferably water-soluble polymers on a chemical way. Only the fragmented fraction of these monomers could form an insoluble coating by cross linking to substrate. The XPS analysis was used to track the alterations in -O-CO- bond percentage on the PP surface. To identify the -COOH groups on substrate surface unambiguously, which have survived the plasma polymerization process, the derivatization with trifluoroethanol was performed. KW - Polymeroberflächen KW - Funktionelle Gruppen PY - 2009 U6 - https://doi.org/10.1140/epjd/e2009-00088-6 SN - 1434-6060 VL - 54 IS - 2 SP - 249 EP - 258 PB - Springer CY - Berlin AN - OPUS4-19607 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Joshi, Ranjit A1 - Friedrich, Jörg F. T1 - Influence of hydroperoxy functionality and hydrogen peroxide on selective surface funtionalization of PP-surface T2 - CAPPSA 2009 4th International Congress on Cold Atmospheric Pressure Plasmas: Sources and Applications CY - Ghent, Belgium DA - 2009-06-22 PY - 2009 AN - OPUS4-19561 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -