Preparation of a good hydrogel supported on a fluorinated polymer film has been achieved by means of simultaneous radiation-induced grafting of N-vinyl-2-pyrrolidone (NVP) onto (tetrafluoroethyleneperfluorovinyl ether) copolymer (PFA). The conditions at which the graft polymerization proceeded with a suitable yield were determined. Ammonium ferrous sulphate (Mohr's salt), as an inhibitor, failed to inhibit the homopolymerization of NVP during the radiation grafting process. In contrast, the addition of Cu2C12 (0.5 wt%) effectively inhibited the homopolymerization process and smooth grafted films with suitable grafting yield were obtained. The grafting onto PFA films, which scarcely swell in any solvent or monomer, was critically controlled by the diffusivity of reactants through the grafted layers initially formed near the film surface. The addition of ZnCI2 (3 wt %) to the monomer solution slightly enhanced the grafting and much smoother grafted films were obtained. The dependence of initial rate of grafting on NVP concentration was of the order 0.54. The graft copolymer possessed good mechanical properties and high thermal and chemical stability. Such non-ionic supported hydrogel on fluorinated polymer may be of interest for some practical use in which high electrical conductivity is not required, as in biomaterials
Посилання на статтю:
Some investigations and characterization of radiation-initiated graft polymerization onto fluorinated copolymer / EI-Sayed A. Hegazy and Massarat B. S. Osman, S. M. Mokhtar and Abo EI-Khair B. Mostafa // Polymer. – 1992. – Vol 33. – P. 4230-4235.