Funktionalisierung von bestrahlten PTFE-Mikropulvern mittels radikalischer Pfropfcopolymerisation und Kopplung mit olefinisch ungesattigten Polymeren

摘要

The initial point for the development of chemically coupled PTFE materials is represented by the chemically coupled PTFE-PA compounds, which exhibit extraordinary wear resistant values and a low coefficient of friction. Compared to the blend materials, this improvement is caused by a complete compatibilization of the PTFE-particles in the PA-matrix due to the formation of chemical bonds. For a chemical coupling of PTFE with other polymer matrices, a further modification of the irradiated PTFE with other functional groups can be achieved using different methods, which is presented here. Irradiated PTFE powders possess persistent radicals, which can be used for graft copolymerisation with different (functional) monomers like styrene, acrylic acid, HEMA, MMA etc. as well as for a direct coupling with olefinic unsaturated matrix polymers such as SBS, ABS, NBR, EPDM etc. in a reactive extrusion process. Regarding these results, developments of novel materials for high performance tribological applications can be realised by simple and competitive irradiation and extrusion processes.