INTERPENETRATING POLYMER NETWORKS OF POLYURETHANE AND VINYL ESTER RESIN FOR REACTIVE INJECTION-MOLDING PROCESS

Three kinds of polyurethane (PU) and vinyl ester resin interpenetrating polymer network (IPN) have been synthesized to study their morphologies and mechanical properties for the potential application in the reinforced reactive injection molding process. For the PU prepared from uretonimine modified pure MDI, the macrophase separation of the IPNs between the rubber and plastic phases was found by DSC measurement and scanning electron microscopy (SEM) observation, whereas the interpenetration between the two networks was also observed on SEM photos at least around the area of interface. However, for the IPN systems including PU prepared from TDI or graft polyol, which was synthesized by using macromer technique, the compatibility between the two phases is excellent. The mechanical properties of these IPNs were measured and could be correlated well enough with their morphologies. The IPN prepared with graft polyol exhibited the best mechanical properties over all IPN specimens studied in this work.