STRUCTURE AND PROPERTIES OF IMPACT COPOLYMER POLYPROPYLENE - I - CHAIN STRUCTURE

In this work, impact copolymer polypropylene (ICPP) was fractionated i nto 4 fractions. ICPP and the 4 fractions were studied using Fourier t ransform infrared and C-13 nuclear magnetic resonance analysis. The re sults demonstrate that fraction A is ethylene-propylene rubber, fracti on B is ethylene-propylene (EP) segmented copolymer, fraction C is eth ylene-propylene block copolymer, and fraction D is polypropylene with a few ethylene monomers in the chain. The differences in properties be tween different impact copolymer polypropylenes should be due to their fractions' differences in composition and chain sequence structure. ( C) 1999 John Wiley & Sons, Inc.