Neue Verfahren zur Oberflächenmodifizierung von Elastomeren für Anwendungen in der Medizin- und Elektrotechnik

Translated title of the contribution: New surface modification techniques for elastomers for medical and electronic applications

Dietmar Lenko

Research output: ThesisDoctoral Thesis

Abstract

Interfacial surface properties of materials such as wettability, polarity, friction, and adhesion play a key role in many technical applications. The present work aims at the development of novel surface modification methods for elastomeric materials, which allows a specific tuning of tribologic properties as well as ensuring optimal adhesion quality. Donning properties of dipped latex goods (for example gloves) made either of NR- or synthetic latices are predominately influenced by the tribologic properties of the elastomeric material Currently, industrial applications utilize elaborate chlorination processes in production where toxic processing chemicals (e.g. chlorine gas) and long reaction times are required to ensure low friction on elastomeric surfaces. In this investigation, new methods were developed to functionalize diene rubber surfaces. Wet chemical processes (e.g. epoxidation), gas phase reactions (fluorination), and photochemical methods, and new polymer coatings were analyzed. The properties of the modified surfaces were characterized spectroscopically (ATR-IR, XPS), measuring contact angle, zeta potential and REM-EDX. To thoroughly evaluate the tribologic properties a new measurement setup was developed, resulting in a substantial correlation between human skin tribology and empirically determined donning properties. Another main topic of the thesis addresses the preparation and development of new composite materials; which show an increased level of delamination resistance when used as insulation material in high voltage applications. To avoid the occurrence of delaminations in high voltage insulating materials (which significantly affect the average lifetime of the generators), newly designed elastomeric damping materials are applied. Silicone elastomers were selected for use due to their high thermal stability (> 180°C) and excellent electrical properties. To ensure a good adhesion as well as adequate covalent bonding between the matrix resin and the silicone elastomer (respectively), the surface of the silicone rubber is functionalized. Resulting evidence shows that mechanical properties can be tuned by the implementing modified silicone elastomers without influencing the electrical parameters. Through investigating the characterization of industrial scale insulation prototypes, evidence strongly suggests that (with the innovative damping elements) a higher lifetime and a better delamination resistance is achievable. This work gives a comprehensive overview as to how specific challenges of the industry can be solved with surface chemistry.
Translated title of the contributionNew surface modification techniques for elastomers for medical and electronic applications
Original languageGerman
QualificationDr.mont.
Supervisors/Advisors
  • Schlögl, Sandra, Co-Supervisor (internal)
  • Lankmayr, Ernst, Assessor B (external), External person
  • Kern, Wolfgang, Assessor A (internal)
Publication statusPublished - 2013

Bibliographical note

no embargoed

Cite this