化学微交联聚氯乙烯的结构和性能

通过氯乙烯/邻苯二甲酸二烯丙酯(VC/DAP)悬浮共聚,合成了含部分凝胶结构的化学微交联PVC树脂,对微交联PVC的玻璃化转变行为、加工性能、消光性能、加热-形变行为和力学性能进行了研究。当DAP用量在0.25%mol以下时,PVC的玻璃化温度变动不大。凝胶含量的增加将导致交联PVC_d~T的光泽度下降,消光性能提高;塑化时间和加工扭矩均增加,加工性能急剧变差;加热变形值下降,最高使用温度提高。凝胶对PVC拉伸性能的影响较为复杂,但压缩永久变形则随凝胶含量的增加而下降,材料的弹性性能逐渐提高。

Structure and Properties of Slightly Chemically Crosslinked Poly (vinyl chloride)

The glass transition behaviors, processability,dulling, heat-defomation behaviors and mechanical properties of slightly chemically crosslinked PVC with partial gel structure prepared by vinyl chloride/diallyl phthalate suspension copolymerization were investigated in this paper, The change of PVC glass transition temperature was little as the dosage of DAP was less than 0.25% mol.The increasing content of gel would result in decreased gloss of crosslinked PVC, improved flattening property,increased fusion time and torque, sharply worsened processability, dropped heat-distortion value and elevated maximum use temperature. The effect of gel on tensile strength was complicated, but permanent compression set of PVC could be decreased with increasing content of gel, and its elasticity could be progressivly enhanced.