Study on Chlorination of Maleic Anhydride Grafted Polypropylene

Abstract

The non-polarity of polypropylene has restricted its use; therefore it needs to be modified. Maleic anhydride grafted polypropylene(PP-g-MAH) is such a kind of modified polypropylene; however its polarity is still low. In order to improve its polarity, chlorinated maleic anhydride-grafted polypropylene (Cl-PP-g-MAH) prepared by free radical polymerization was carried out using PP-g-MAH as reaction material, carbon tetrachloride (CCl4) as solvent and benzoyl peroxide (BPO) as initiator. The products were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Nuclear Magnetic Resonance Spectroscopy (NMR). The effects of the reaction temperature, reaction time, flow rate of chlorine and concentrations of PP-g-MAH and BPO initiator on the degree of chlorination were studied. The optimum technological conditions were obtained, and the surface tension, light transmission, particle size and tensile strength of chlorinated maleic anhydride grafted polypropylene were better than those of maleic anhydride grafted polypropylene. After modification by maleic anhydride and chlorine, PP could meet commercial needs in the fibre composites, adhesives, printing inks, coatings and plastics industries.