Mechanistic aspects of the thermal stabilisation of PVC by organotin compounds

When subjected to heat and mechanical shear PVC decomposes via the elimination of HCl. This process is controlled most efficiently by the use of organotin stabilisers. This review outlines the basic degradation/stabilisation mechanisms which are involved in these processes. The organotin compounds of most commercial significance receive particular attention. Model compound studies which highlight potential stabilisation mechanisms are discussed but emphasis is placed on in‐situ studies which are much more realistic. Finally the phenomenon of synergism is discussed with reference to conventional alkyltin and the more novel estertin compounds.