Effect of allyl chloride comonomer on the thermal degradation of poly(methyl methacrylate-co-allyl chloride)

Abstract

The degradation behaviour of copolymers of allyl chloride and methyl methacrylate has been studied by using thermogravimetry in dynamic nitrogen and thermal volatilisation analysis (TVA) under vacuum, with programmed heating at 10°C/min. Volatile products have been separated by sub-ambient TVA and identified by spectroscopic methods. The cold ring fraction and partially degraded polymer have been examined by IR spectroscopy. Copolymers of allyl chloride and methyl methacrylate are more stable than homopolymer. On degradation, the major product is methyl methacrylate monomer. Minor products include carbon dioxide, hydrogen chloride and methyl chloride. In the case of copolymer I two additional products, methanol and lactone have also been identified. Copolymer I with high allyl chloride contents, shows the formation of anhydride ring structures in the cold ring fraction and in the residue after partial degradation. The mechanism of degradation is discussed.