Influences of dispersion degree of macromolecular costabilizers on the thermal stabilization of poly(vinyl chloride)

摘要

Synergetic effects of ethylene-vinylacetate eopolymers (EVA) with zinc stearate, calcium stearate synergetic soap on the thermal stabilization of poly(vjnyl chloride) (PVC) was investigated by colorimetry. Under the present conditions, a marked synergetic effect was observed with increasing vinyl acetate content of EVA. The image processing evaluation for the compatibility of EVA indicated that the EVA were finely dispersed into PVC with increased acetyl group contents. These results suggest that the effects of EVA were markedly dependent on their compatibility with PVC. The values obtained for relationships involving NCG (distance to nearest center of gravity) or A (area) of EVA particles in compound PVC and amounts of EVA added were useful parameters to evaluate the compatibility of additives with the matrix.