纳米碳酸钙性质对聚氯乙烯复合材料界面及性能的影响

选择了不同的表面处理剂对纳米CaCO₃进行表面改性. 研究了不同表面处理剂对CaCO₃/PVC纳米复合材料微观结构、界面结合强度、力学性能及加工性能的影响.研究表明，钛酸酯偶联剂处理可使纳米CaCO₃颗粒在PVC基体中达到良好分散，明显改善纳米CaCO₃颗粒与PVC基体之间的界面结合，并提高其界面结合强度.力学性能和流变性能研究表明，钛酸酯处理的纳米CaCO₃填充PVC具有更高的拉伸强度、冲击强度以及更低的平衡转矩， 而且CaCO₃/PVC复合材料的冲击韧性在填充量为20%(mass)时达到最大值26.5 kJ•m^-2，是纯PVC的4倍.

Effect of properties of CaCO3 nanoparticles on interface and properties of poly(vinyl chloride) composites

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.