热稳定剂对PVC/PU共混体系性能的影响

INFLUENCE OF THE HEAT STABILIZER ON THE PROPERTIES OF PVC/PU BLENDS

本文研究了ＰＶＣ的热稳定剂对ＰＶＣ／ＰＵ共混体系性能的影响．通过红外光谱、热分析和透射电镜等手段探讨造成共混物性能差别的原因．结果表明：金属皂类稳定剂最有利于共混体系的韧性改善，而有机锡化合物、铅盐均不利于提高共混物的缺口冲击强度．不同的稳定剂对共混体系的应力－应变行为影响不大．溶剂抽提和红外光谱结果表明，加工过程中可能导致的化学交联不起显著的作用．动态力学的结果表明，不同的稳定剂体系导致ＰＵ与ＰＶＣ的两相相容性有差别，从而导致共混体系相态结构的差异，透射电镜研究结果证实了这一点．

The toughness of PVC/PU blends depended greatly on the heat stabillizer of PVC. Among the three kind of widely used heat stabilizers, stearate (Zinc and Barium et al.) were most benificial to improve the notched impact strength, while the mechanical property had little difference. Chemical and IR analysis revealed that the possible chemical crosslinking during the heat process is not the main reason for this difference. Dynamic mechanical analysis and transmission electron microscopy results proved that blends had different phase structure with different stabilizer wihch is responsible for the toughness difference.