原位聚合聚氯乙烯树脂的合成及性能

研究了氯乙烯悬浮聚合时添加氯化聚乙烯(CPE)冲击改性剂、CaCO3填料、润滑剂及热稳定剂对聚合反应的影响，并对得到的可直接加工的原位聚合聚氯乙烯(RTUPVC)树脂的性能进行了表征。结果发现：CPE和CaCO3的加入均使达到相同压降的聚合时间缩短，氯乙烯聚合转化率相应减小；RTUPVC树脂的粒径随CPE粒径和用量的增大而增大，而CaCO3含量对RTUPVC树脂粒径影响不大；润滑剂和热稳定剂的加入，对聚合反应起延缓作用，但对RTUPVC树脂粒径影响不大；RTUPVC树脂加工塑化时间随CPE含量的增加而减少；相同CPE用量时，RTUPVC树脂的冲击强度和拉伸强度明显高于PVC/CPE共混物。

Preparation and Properties of In Situ Polymerization of Poly(vinyl chloride)

The in situ suspension polymerization of vinyl chloride was carried out in a system containing chlorinated polyethylene (CPE, the impact modifier), CaCO 3 (the filler), lubricants and thermal stabilizers to generate ready-to-processing PVC resins (RTUPVC). The effects of the various additives on the polymerization and the properties of the resins were investigated. The polymerization time until certain pressure drop was reduced with the addition of CPE and CaCO 3, however, the lubricant and thermal stabilizer retarded the polymerization. CPE improved the plasticity and both impact and tensile strengths. RTUPVC resin exhibited higher impact and tensile strengths than PVC/CPE blends with the same CPE content. The particle size of the resin was increased with increasing content of CPE, but not affected by other additives.