AbstractThe characteristics of glycidyl methacrylate (GMA)–modifiers, including the polymerization properties, curing properties, and thermal stability, were studied. The degree of crosslinkage for (GMA–modifier)polyols increases with increasing hexamethoxymethylmelamine (HMMM) content and reaches maximum when HMMM content is about 40 wt %. The gels obtained from thermal free‐radical polymerization for GMA‐modifier monomer decrease with increasing acid value. UV curing experiments indicate that the energy of ultraviolet might be insufficient to promote the curing reaction through transetherification with short‐term irradiation. Kinetic parameters for the thermal decomposition of the polymer were measured with TG thermograms. © 1993 John Wiley