On the basis of our earlier work, extensive experiments were conducted to further investigate grafting vinyl acetate onto different films (10 types of films and 20 binds of film combinations), using various photoinitiators, for example, BP, AQ, ITX, XAN, Irgacure 651 and 184, acetone, and cyclohexanone, irradiated by UV radiation. Several means were applied to confirm the grafted PE-g-PVAc film. The results showed that increasing UV radiation intensity is favorable for grafting polymerization and the far UV radiation plays a decisive role. Among the photoinitiators tested, BP is the best one, because it was found that BP initiates the grafting copolymerization efficiently, and other initiators are less effective. To various combined substrates, the affinity between the monomer and films, the reactivity of hydrogens on the substrates, and the transparence of the top film to UV radiation are main factors affecting polymerization. Both direct method (FTIR) and indirect methods (contact angle, color reaction, absorption of dye and water) verified the true product PE-g-PVAc.