关键词: 聚氯乙烯, 纳米碳酸钙, 界面结合, 力学性能, 流变性能, 增韧, 动态力学性能

Abstract: Poly(vinyl chloride) composites were prepared via a melt blending filled with CaCO₃ nanoarticles, which were pretreated with titanate coupling agent and stearic acid respectively.The effects of different agents on the microstructure of composites, the interfacial cohesion of CaCO₃/PVC and the mechanical properties of composites were studied. The microstructure of CaCO₃/PVC nanocomposites was characterized by scanning electron micrograph, and the interfacial cohesion between CaCO₃ particles and PVC matrix was determined by dynamic mechanical analysis experiments. It was found that CaCO₃ nanoparticles were uniformly dispersed in PVC matrix and had a good interfacial cohesion with the matrix after treatment with titanate coupling agent. A little amount of nanoparticles agglomeration and some cavities were found after treatment with stearic acid, while a lot of agglomeration and cavities occurred when filled with untreated CaCO₃ nanoparticles.Better interfacial cohesion and stronger interfacial adhesion strength were obtained after the inorganic filler was pretreated with titanate coupling agent, with which the PVC composites filled had lower equilibrium torque, higher tensile strength and notched impact strength. The notched impact strength of composites reached 26.5 kJ•m^-2, which was about 4 times as high as that of neat PVC composites, when the mass ratio of nano-CaCO₃/PVC was 20/100.

Key words: 聚氯乙烯, 纳米碳酸钙, 界面结合, 力学性能, 流变性能, 增韧, 动态力学性能