The thermooxidative degradation of poly(vinylchloride): 3. The stabilisingaction of dibutyltin maleate and trisnitro(1,3-dihydroxy-2-hydroxymethyl-2-nitropropane). Effect of outdoor exposure on PVC

The effects of the stabilising action of admired mixtures of dibutyltin mal eate and trisnitro and its ester homologues on polyvinyl chloride exposed t o natural atmosphere were studied. The degradation and stabilisation reacti ons were monitored by i.r., colour formation, tensile strength, elongation at break, reduced viscosity as well as determination of time to embrittleme nt. Observed reductions in carbonyl group formation, lack of colour formati on and generally improved mechanical properties of the stabilised PVC sampl e indicated effective reduction in degradation reactions. The stabilising a gents containing 7.2x10(-3)mol% DBTM in admixture with 10 x 10(-4) mol% of stearyl ester of trisnitro was most effective. (C) 1999 Elsevier Science Lt d. All rights reserved.