RADIATION-INDUCED FUNCTIONALIZATION OF FLUOROPOLYMERS

The electron radiation induced changes in the chemical composition and structure of tetrafluoroethylene homopolymer (PTFE) as well as its copolymers with hexafluoropropylene (FEP) and perfluoropropylvinylether (PFA) were studied mainly by infrared spectroscopy. Irradiations carried out in the presence of air cause the formation of acid fluoride end groups, which subsequently hydrolyzed to carboxylic acid end groups in the presence of moisture. The irradiation of these three fluoropolymers yield essentially the same results. However, the degree of oxidation is higher in the case of FEP and PFA copolymers than for PTFE under the same irradiation conditions. In the second part, we describe the covalent linkage of (aminopropyl)triethoxysilane to the irradiated fluoropolymer surfaces. It should be possible to use such modified materials containing triethoxysilane functionality as 'coupling agents' to bond fluoropolymers onto glass or metal.