THE THERMAL-DEGRADATION OF GLYCIDYL METHACRYLATE-METHYL METHACRYLATE COPOLYMERS

Copolymers of glycidyl methacrylate and methyl methacrylate with widel y differing compositions have been studied by thermal volatilisation a nalysis (TVA), thermogravimetry (TG), differential thermal analysis (D TA) and pyrolysis-mass spectrometry (Py-MS) techniques. The apparent a ctivation energies for the decomposition of the copolymers were calcul ated from the results of thermo-gravimetric experiments. The condensab le volatile degradation products have been identified after separation by subambient TVA (SATVA). The cold ring fraction (CRF) and the struc tural changes in the residue in the course of degradation were examine d. Non-condensable products formed during TVA degradation were identif ied using a mass spectrometer attached to the TVA apparatus. The two m onomers are the major products of degradation of the copolymers, which , unlike the PMMA, also yield CRF products. Anhydride rings are detect ed in the CRF and in the residue from partial degradation to 340 degre es C. Glycidyl methyl ether is also one of the degradation products. A mechanism of degradation is proposed.