Free-Radical Cross-Linking Polymerization of Diallyl Terephthalate in the Presence of Microgel-like Poly(allyl methacrylate) Microspheres

Abstract

The cross-linking polymerization of diallyl terephthalate (DAT) was explored in detail in the presence of microgel-like poly(allyl methacrylate) (PAMA microsphere) as an extension of our continuing studies concerned with the elucidation of cross-linking reaction mechanism and the control of network formation in the free-radical cross-linking polymerization of multivinyl compounds. Thus, PAMA microspheres were prepared by the emulsion polymerization of AMA as reactive cross-linked polymer microspheres having abundant pendant allyl groups. The polymerization of DAT in the presence of microsphere was conducted in bulk using BPO as initiator at 80 °C. The gel-point conversion became higher with an increase in the feed amount of microsphere. No gel effect was observed. Variation of RI-monitored SEC curves with conversion suggested the copolymerization of the pendant allyl groups present on the surface of microsphere with DAT; this was also supported by light scattering and 1H NMR spectroscopy. The swelling ratios of the gels in the presence of microsphere were not high even just beyond the gel points, suggesting a preferential incorporation of microsphere into the gel. These are discussed mechanistically.