The Effect of Tri(n-butyl) Tin(IV) –2– [3–Benzoyl phenyl] Propionate on the Degradation and Stabilisation of PVC in Inert and Oxidative Atmospheres

Abstract

Tri(n-butyl) tin(IV)–2–[3–benzoyl phenyl] propionate has been used to enhance the shelf life of rigid poly (vinyl chloride) (PVC). Studies of the thermal degradation of PVC have been a prime focus for a long time. Different substances have been tried to control and stabilise the process of thermal degradation. In the present work the aforementioned stabiliser has been used for this purpose. The samples of PVC containing different amounts of the stabiliser were prepared and treated at 190 ± 3 °C. The effect of the stabiliser on the degradation in nitrogen and air environments was studied through conductometric and spectroscopic measurements. The stabiliser was effective in slowing down the process of degradation. It also increased the initial induction period, i.e. the time during which no sign of degradation were observed. About 3% of stabiliser reduced the rate of the degradation of PVC by half, and almost doubled the induction period. It was more efficient in nitrogen than in air. These findings indicate that tri(n-butyl) tin(IV)–2–[3–benzoyl phenyl] propionate is a good inhibitor as well as an effective retarder.