Radiation-induced grafting of methyl-α,β,β- triflouroacrylate onto tetrafluoroethylene-propylene copolymer

Abstract

Radiation-induced grafting of flourine-containing monomer,methyl—α,β,β—trifluoroacrylate (MTFA) onto tetrafluoroethylene-propylene copolymer (TFEP) has been studied. The grafting was performed in a homogeneous medium: the polymer solution was irradiated with 60Co gamma rays in the presence of monomer. The irradiation was carried out in vacuum at room temperature, with total absorbed dose up to 420 kGy at dose rates 5, 10, and 15 kGy/h. All of the total weight increase, the graft yield, and the homopolymer formation showed similar complex dependences on absorbed dose. After nonlinear increase, it reached maximum and then decreased. The maximum was higher and reached at lower absorbed dose when irradiation was performed at lower dose rate. The grafted samples were characterized by IR spectroscopy and were subjected to the molecular weight distribution measurement (GPC). Surface characterization using scanning electron microscope was also done. From these results a model for the grafting process was proposed.