BULK THERMAL POLYMERIZATION OF DIETHYLENE GLYCOL BIS(ALLYL CARBONATE)AS STUDIED BY DIELECTRIC-RELAXATION SPECTROSCOPY

Broad-band dielectric relaxation spectroscopy (DRS) has been used to s tudy the changes in molecular relaxation behaviour when diethylene gly col bis(allyl carbonate) (CR39 monomer) is polymerised thermally in it s bulk state. As polymerisation proceeds the dielectric alpha-relaxati on process broadens markedly and moves to higher temperatures while, a t the same time, a small low-temperature beta-relaxation process incre ases in its intensity and moves to higher temperatures. The dielectric loss spectra are shown to provide a convenient fingerprint that indic ates the extent of cure in partially cured materials.