THE EFFECT OF MECHANICAL DEGRADATION ON THE PYROLYSIS OF POLY(METHYL METHACRYLATE) AND ITS COPOLYMERS

The effect of mechanical degradation in air on the thermal degradation of poly(methyl methacrylate) and its copolymers with methacrylamide and hydroxymethyl methacrylamide has been studied by pyrolysis-evolved gas-infrared analysis. It has been shown that degradation results in reduced zip length, decreased yield of monomer, and evolution of carbon dioxide, carbon monoxide, methanol and methane. These latter gaseous products can lead to erroneous interpretation and to postulation of incorrect degradation mechanisms. The results demonstrate that the effects of mechanical degradation must be considered when preparing samples for thermal degradation studies.