SynopsisChanges in the quantities of active stabilizing components during thermal aging of plasticized poly(viny1 chloride) containing a mixture of calcium and zinc stearates were analyzed. A mathematical model of the stabilization process by using the stabilizer mixture and a computer program for analyzing the process of PVC thermal degradation after the beginning of HCl evolution are given.

SynopsisA model of the action of chemically homogeneous thermal stabilizers of poly(viny1 chloride) is shown. Based on the described computer program and experimental data, the proposed model is confirmed and rate constants of the reaction of stabilizers with HCI and the effect of the products of this reaction on the kinetics of PVC degradation are calculated.