Effect of stabilizers in the thermal treatment of PVC—XII.: An I.R. spectroscopic study of the complexation of Na and Zn stearates in PVC

Abstract Effect of the 2:1 combination of Na and Zn stearates on the stabilization of PVC exposed to thermal stress at 180° in air has been studied by i.r. spectrometry (1900−1350 cm −1 ) and by determination of Zn, Na and Cl − in the decomposition products of the stearates (NaCl, ZnCl 2 ). Complexation of both components in PVC mixtures proceeds very easily; a 2:1 complex is the only one formed in the mixture. One stearate (Na) of the binary mixture is consumed selectively over a substantial part of the thermal stability period. The stearate mixture studied has no significant synergistic effect.