GRAFTED INTERPENETRATING POLYMER NETWORKS

A new class of interpenetrating polymer network (IPN) has been studied in which grafting reactions between the two components are varied. Small-angle neutron scattering of grafted and nongrafted IPNs shows that grafting greatly enhances the miscibility of the components. Five nonfunctionalized poly(methyl methacrylates) (PMMAs) with alkacrylate, methacrylate, acrylate, and cu-methylstyrene end groups were dissolved in styrene-divinylbenzene and polymerized. Small-angle X-ray scattering was used to characterize the extent of phase separation. The uniformity of the IPNs is strongly dependent on the grafting efficiency. Crafted and nongrafted IPNs were also made from the PMMAs and polyethylene glycol diacrylates. Thermal studies showed one transition in the grafted samples and two distinct transitions in a nongrafted sample.