Thermolysis of poly(chloroethyl methacrylates) and poly(chloroethyl acrylates)

Poly(ethyl acrylates) and poly(ethyl methacrylates), chlorinated in the side groups, release chlorine and undergo intermolecular cross-linking if heated to temperatures up to 500 K. These processes are most significant in the cases of the dichloroethyl eaters. At T > 500 K both acrylate and methacrylate polymers decompose into low molecular fragments. In methacrylate polymers this process predominantly consists of depolymerization (formation of monomer). As far as the onset temperature for mass loss is concerned the chlorinated polymers definitely exhibit a lower stability than the nonchlorinated ones. Oxygen enhances cross-linking of the mono- and dichlorethyl methacrylate polymers but retards or prevents cross-linking in all other cases. The simultaneous action of both heat and UV light reduces the thermal stability. This effect is quite significant in the cases of the methacrylate polymers that are prone to unzipping.