period of 15 min under stirring and then the mixture was stirred for another 15 min the solution was neutralized with nahco 3 and copolymer recovered by precipitation in water and washing 3 times in methanol prior to vacuum drying the resulting elastomeric material 2c was completely soluble in thf the solubility of this material suggests that the silane substituent previously introduced into the copolymer was successfully capped by reaction with the dimethyl 3 3 3 trifluoropropylchlorosilane this conclusion is further supported by the 19 f nmr spectra which showed the characteristic fluorine chemical shift of the trifluoropropyl group at 68 ppm elemental analysis of the material showed 0 39 si and 0 1 n corresponding to 2 1 to 2 2 wt of siloxane grafted groups another portion of mixture 2a 30 ml was combined with titanium diethoxy diacetylacetonate 0 1 ml and cast into a film on a calendered polytetrafluoroethylene ptfe sheet after standing overnight the film about 0 1 mm thick was insoluble in thf and had a tensile strength of 1140 psi a plastomeric copolymer of vinylidene fluoride and hexafluoropropene commercially available under the trademark kynar flex 2801 30 g was dissolved in 300 ml of anhydrous thf and mixed with sodium mathoxide 0 54 g 3 aminopropyltrimethoxysilane 1 8 g and tetrabutylammonium bromide 0 15 g the mixture was heated at reflux for 7 h viscosity increased noticeably a portion of the mixture 30 ml was diluted with 5 ml of thf to reduce viscosity and then titanium diethoxy diacetylacetonate 0 05 ml was added the catalyzed mixture was cast on a ptfe sheet after evaporation of the solvent a film.