Catalytic synthesis and characterization of well-defined polypropylene graft copolymers

Isotactic polypropylene graft copolymers including isotactic-polypropylene-graft-polystyrene (PP-g-PS) and isotactic-polypropylene-graft-poly(methyl methacrylate) (PP-g-PMMA) were prepared by atom transfer radical polymerization (ATRP) initiated by hydrochlorinated polypropylene (PP-Cl), a macroinitiator synthesized from pendant vinylbenzene group-containing functional polypropylene. The functional polypropylene was formed by copolymerization of propylene and 4-(3-butenyl)styrene (4BuSt) upon the addition of hydrogen using a rac-Me2Si[2-Me-4-naph(Ind)]2ZrCl2/MAO catalytic system. The PP-g-PS and PP-g-PMMA copolymers were obtained and characterized with proton nuclear magnetic resonance (1H NMR), differential scanning calorimetry (DSC), and high-temperature gel permeation chromatography (GPC) etc.