SynopsisBased on experimental data, changes of properties of plasticized PVC containing stearates of Ca, Zn, Cd, and Pb stabilizers during thermal degradation are discussed. The mechanism of action of these stabilizers is described in kinetic form.

No abstract

degradation process is discussed. homogeneous stabilizers has been worked out and experimentally tested. The influence of components of PVC compositions on the character of the polymer An equation permitting to calculate the beginning of HCl splitting off for chemical ZUSAMMENFASSUNG: des thermischen Abbaus des Polymeren diskutiert. der Dehydrochlorierung fur chemisch homogene Stabilisatoren gestattet. Es wird uber den EinfluB der Bestandteile von PVC-Mischungen auf den Verlauf Ferner wird eine Gleichung abgeleitet und experimentell gepruft, die die Ermittlung Materials Polyvinyl chloride: typical industrial PVC types were used: Hostalit PVP 3475, Hostalit Plasticizers: purificated industrial products: DOP, DOZ, TKP. Stabilizers: pure chemical reagents: stearates of Ca, Cd and Zn, dibasic lead stearate, tribasic lead sulphate. Besides those stabilizers, some different industrial stabilizers have been chosen: type Irgastab, Mark, Nuostab and Sicostab. PVP 5470, Geon 121, Vestolit B 7021.Antistatics: laboratory samples of following chemical structure were used:

O n the Mechanism of Action of Epoxy Stabilizers in Poly(viny1 Chloride) Compositiom Epoxy compounds are generally used as thermal stabilizers of PVC. On the other hand, these compounds are used as plasticizers of polymer. The stabilizing action of epoxy compounds consists in the formation of chlorohydroxy derivatives with liberated hydrogen chloride.14

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.