Dynamics of Polymerization in Reactive Polymer Processing

Reactive polymer processes such as reaction injection molding are characterized by rapid exothermic reactions that convert prepolymers to high molecular weight plastics in irregularly shaped mold cavities. The time scales of the reaction are often much shorter than the time scales for heat conduction, causing significant non-uniformities in temperature and conversion profiles in the asymmetric cavity. These non-uniformities manifest themselves as significant differences in morphology, degree of crystallinity and mechanical properties across the final part.