氯化原位接枝改性CPVC流变行为的研究

采用氯化原位接枝技术制备了苯乙烯(St)、甲基丙烯酸甲酯(MMA)、丙烯酸-2-羟基乙酯(HEA)、丙烯酸-2-羟基丙酯(HPA)和丙烯酸丁酯(BA)等五种单体改性的CPVC.用毛细管流变仪测定了它们的流变行为.讨论了CPVC和改性CPVC的熔体粘度与剪切速率、剪切应力以及温度的关系.结果表明:CPVC和改性CPVC熔体均为假塑性流体,改性CPVC的假塑性增强,熔体表观粘度低于CPVC的熔体表观粘度.在190～205℃温度范围,两者的对数表观粘度与1/T呈非线性关系.CPVC-g-PMMA对温度和剪切应力更加敏感,CPVC-g-PHEA熔体的流动性明显高于CPVC及其他四种单体改性的CPVC.

Study on Rheological Behavior of Modified CPVC Prepared Using In-situ Chlorinated Graft Method

Grafting chlorinated polyvinyl chloride(CPVC) with styrene(St),methyl methacrylate(MMA),2-hydroxy ethyl acrylate(HEA),2-hydroxy propyl acrylate(HPA) and butyl acrylate(BA) was prepared using in-situ chlorinated graft method. Rheological behaviors of CPVC and modified CPVC were studied by capillary rheometer.The relationships of shear stress,shear rate and temperature to melt apparent viscosity were discussed.The results showed that the melts of CPVC and modified CPVC were pseudo-plastic fluids.The melt apparent viscosity of modified CPVC decreased rapidly comparing with CPVC.CPVC-g-PMMA was more sensitive to temperature and shear stress than CPVC and other modified CPVC.