Multi functionalization of polypropylene with controlled degradation and its structure characterization

摘要

The multi functionalization of isotactic polypropylenes (iPP) with glycidyl methacrylate (GMA) was carried out by in situ chlorinating graft copolymerization (ISCGC), in which chlorine (Cl2) is used as a radical initiator as well as a radical scavenger. The molecular weight measurement indicates that functionalized iPP with controlled degradation could be obtained because the unstable radicals that induce iPP degradation could be terminated quickly by chlorine. Owing to the unique allyl-containing structure of GMA, multi functionalized iPP could be synthesized under the effect of chlorine, which contained both epoxy groups and C=C double bonds as well as trace amount of chlorine atoms in the functionalized polymer structure. The structure of both the functionalization polymer and homopolymer formed in this system were analyzed by FTIR and 1H NMR. The mechanism of grafting reaction, iPP chain degradation, and GMA homopolymer formation scheme in ISCGC were proposed. The thermal properties of the functionalized polymer are also discussed.