AN INVESTIGATION OF THE THERMAL-STABILITY AND CHAR-FORMING TENDENCY OF CROSS-LINKED POLY(METHYL METHACRYLATE)

The thermal degradation of two network copolymers of methyl methacryla te was studied as a function of the chemical nature of the cross-linki ng agent and the frequency of cross-links. Unlike the linear homopolym er, both the trimethylolpropane triacrlylate and trimethylolpropane tr imethacrylate networks were found to char when burned. The correspondi ng derivative thermograms indicate that there are dramatic differences in the thermal degradation of these polymers even in the absence of o xygen. These differences are interpreted in terms of a simple model fo r the kinetics of depolymerization.