聚甲基丙烯酸甲酯／纳米SiO2复合材料研究

目的分析纳米SiO2对聚甲基丙烯酸甲酯／纳米SiO2复合材料基体的各方面性能的影响．方法采用在位分散聚合方法制备聚甲基丙烯酸甲酯／纳米SiO2复合材料，利用硅烷偶联剂KH-570对纳米颗粒表面进行改性，比较改性前和改性后的纳米SiO2及物理方法和化学方法改性的纳米SiO2对复合材料抗折性能、耐热性、耐溶剂性能的影响，并利用扫描电镜拍摄断面照片，观测基体内纳米颗粒的分散形态与材料断面．结果经KH-570表面改性后的纳米材料在基体中分散均匀，复合材料的力学强度虽没有明显提高，但将其玻璃化温度提高了10℃，耐溶剂性也较聚甲基丙烯酸甲酯有明显改善；物理方法处理纳米颗粒表面改性效果更加突出．结论表面改性后的纳米SiO2对聚甲基丙烯酸甲酯的耐热性、耐溶剂性能有明显改善，利用物理方法对纳米颗粒表面改性更适用于工程应用．

Study on Polymethyl Methacrylate/Nano-SiO2 Composites

The polymethyl methacrylate/SiO2 composites were prepared by in-situ polymerization, and the surface of Nano-SiO2 was modified by KH-570 through physical and chemistry, the two kinds of surface modified method. The properties of the composites filled with different-surface SiO2 on mechanics, thermal stability and resistant solvent were compared;the configuration of the cross section by SEM was observed. The results revealed that Nano-SiO2 could be dispersed uniformly when the surface was modified by KH-570;the strength of mechanics was not improved but the glass transition temperature was improved 10℃ ;the performances on solvent resistance and toughness were also improved. Physical method was effective on surface modification and more suitable for the engineering application.