Study of the kinetics, mass transfer, and particle morphology in the production of high-impact polypropylene

A sequence of experimental steps was perfected to produce high-impact modified polypropylene (PP), and to study the influence of particle morphology and rubber content on the reaction kinetics, especially in terms of mass transfer limitations. It was found that after a critical copolymer content at approximately 40% (with respect to total weight), it was impossible to obtain high reaction rates. This is thought to be the result of a fundamental change in particle morphology attributed to the presence of a soft EPR copolymer phase in the micropores. (C) 2001 John Wiley & Sons, Inc.