加工型ACR的合成及在PVC中的应用

Synthesis of processable ACR and its application in PVC

针对聚氯乙烯(PVC)/CaCO_(3)在混炼过程中存在的塑化困难、共混时间较长、不完全塑化等加工难点以及制品表面粗糙、无光泽等市场痛点,以叔十二烷基硫醇(TDDM)为链转移剂,设计并合成了一种加工型丙烯酸酯类共聚物(ACR-P)。探究了TDDM和ACR-P的添加量对PVC/CaCO_(3)/ACR-P复合材料力学性能、流变性能、微观形貌及塑化效果的影响。结果表明,随着TDDM添加量的增加,ACR-P特性黏度逐渐下降,PVC/CaCO_(3)/ACR-P复合材料的拉伸强度和储能模量明显提高,塑化时间大幅缩短,同时冲击强度略有增加。当TDDM添加质量分数为0.8%时,PVC/CaCO_(3)/ACR-P复合材料的拉伸强度达到52.79 MPa,与PVC/CaCO_(3)相比,提高了50.27%;塑化时间由71 s缩至32 s。ACR-P添加量的增加显著地影响了PVC/CaCO_(3)/ACR-P复合材料的力学性能和加工性能,当ACR-P添加量为10份时,复合材料的拉伸强度达到61.12 MPa,与PVC/CaCO_(3)相比,提高了87.6%;塑化时间由115 s缩至25 s。动态热机械分析测试显示PVC/ACR-P复合材料只有一个玻璃化转变峰,说明PVC树脂和ACR-P两相是一个相容体系。从扫描电子显微镜可以观察到PVC/CaCO_(3)复合材料中两相界面清晰,ACR-P的引入使复合材料的界面变得模糊,这表明复合材料的相容性得到改善,力学性能和加工性能得到提升。

To address the processing difficulties such as difficult plasticization,long blending times,incomplete plasticization during the blending process of Polyvinyl Chloride(PVC)/CaCO_(3),and market pain points like rough surface and lack of gloss of the products.,a processing-type acrylate copolymer(ACR-P)was designed and synthesized with tert-dodecyl mercaptan(TDDM)as chain transfer agent.The effects of the addition amount of TDDM and ACR-P on the mechanical properties,rheological behavior,microstructure,and plasticization effect of the PVC/CaCO_(3)/ACR-P blends were explored.The results show that with the increase in the addition amount of TDDM,the intrinsic viscosity of ACR-P gradually decreases,and the tensile strength and storage modulus of the PVC/CaCO_(3)/ACR-P blends significantly increase,while the plasticization time is substantially shortened,with a slight increase in impact strength and elongation at break.When the addition mass fraction of TDDM is 0.8%,the tensile strength of the blend reaches 52.79 MPa,a 50.28%increase compared to PVC/CaCO_(3),the plasticization time is reduced from 71 s to 32 s.The increase in the addition amount of ACR-P significantly affects the mechanical properties and processing performance of the PVC/CaCO_(3)/ACRP blends.When the addition amount of ACR-P is 10 phr,the tensile strength of the blend reaches 61.12 MPa,an 87.6%increase compared to PVC/CaCO_(3),the plasticization time is reduced from 115 s to 25 s.Dynamic thermomechanical analysis shows that the PVC/ACR-P blend has only one glass transition peak,indicating that the PVC resin and ACR-P form a compatible system.Scanning electron microscope observations reveal that the interface between the two phases in the PVC/CaCO_(3) composite material is clear,while the introduction of ACR-P makes the interface of the blend blurred,indicating that the compatibility of the blend is improved,and both mechanical properties and processing performance are enhanced.