Modification And Property Research Of Ethylene-vinyl Acetate Copolymer

The main aim of this paper was the modification of ethylene-vinyl acetatecopolymer (EVA) by chlorination and in-situ chlorinating grafting copolymerization.There were no initiators added into reactive system, chlorine radicals derived from thedecomposed chlorine molecular were used as to initiate grafting reaction of EVA.Chlorination and grafting were simultaneous during the ISCGC.The structure of chlorinated EVA (CEVA) with different chlorine content werecharacterized by FT-IR, GPC and1H-NMR, which verified the feasibility ofmodification of EVA by chlorination and ISCGC. We could know that there werecarbon-carbon double bonds and vinylidene chlorines structure in the CEVA andCEVA-cg-MMA molecular chain. From the results of GPC, we knew that thecarbon-carbon were produced by the removal of HCl, not the oxide degradation. Forchlorinated EVA, we calculate the content of chemical group units by1H-NMR, andanalyzed the chlorinated mechanism. The grafting degree of CEVA-cg-MMA withdifferent MMA usage were calculate by1H-NMR also. The grafting degree wereincreased then decreased as the MMA usage increased. The content of carbon-carbondouble bonds and vinylidene chlorines structure were different with the grafting degreeis different. From the results of DSC, the crystallization degree were decreased and theglass transition temperature (Tg) increased,as the chlorine content of CEVA increased;the glass transition temperature (Tg) of CEVA-cg-MMA decreased as the graftingdegree increased.In addition, we also test the properties of CEVA and CEVA-cg-MMA which arefilm of coating. We researched the evolution of glossiness,impact strength,adhesionand hardness with chlorine content increased. We confirmed the MMA usage andchlorine content by discussed the properties of CEVA-cg-MMA.