P(MMA-St)/SiO_2纳米复合材料的制备及性能研究

Preparation and Performance of Composite of Nanosilica/Poly(methyl methacrylate-co-styrene)

采用硅烷偶联剂(KH-570)对纳米二氧化硅(SiO_2)进行有机化处理,然后将其与甲基丙烯酸甲酯(MMA)和苯乙烯(St)按一定比例进行原位悬浮聚合,得到甲基丙烯酸甲酯-苯乙烯共聚物P(MMA-St)/SiO_2纳米复合材料。利用傅里叶红外光谱、凝胶渗透色谱仪、热失重分析仪、透射电子显微镜等对纳米SiO_2及复合材料的结构、热稳定性、力学性能及加工流动性进行了分析和表征。结果表明,在保证良好加工性能的前提下,复合材料的热稳定性、力学性能均得到了显著提升,并且纳米SiO_2的加入使聚合物相对分子质量增大,相对分子质量分布变窄。

Nano-SiO2 was modified with a coupling agent （KH-570）, and was mixed with methyl methacrylate and styrene. The system was subjected to a suspension polymerization leading to P（MMA-St）/nano-SiO2 composites, in which Nano-SiO2 was evenly dispersed in the matrix. The structure and properties of the composites were characterized using Fourier transform infrared spectroscopy, gel permeation chromatography, thermal gravimetric analysis, TEM, universal testing machine, and torque rheometer. Because of the interaction between nano-SiO2 and P（MMA-St） ,the molecular weight became larger, and the molecular weight distribution became narrow. Thermal stability and mechanical performance of the composites were significantly im- proved.