改性纳米二氧化硅增强增韧聚对苯二甲酸丁二醇酯

采用四辛基溴化铵(TOAB)改善纳米二氧化硅颗粒(SiO_2)的分散性,并在SiO_2表面进行聚对苯二甲酸丁二醇酯(pCBT)的接枝改性。以不同含量改性的SiO_2(0.1%~2%(质量分数))与环状聚对苯二甲酸丁二醇酯(CBT)熔融共混,原位聚合制得SiO_2/pCBT纳米复合材料。纳米复合材料的结晶性能和力学性能表征结果表明:随着SiO_2含量的增多,结晶度逐渐提高;与纯pCBT相比,添加1%(质量分数)SiO_2的复合材料的杨氏模量提高了22%,断裂吸收能提高约56%;此外,SiO_2还能显著提高pCBT纳米复合材料的弹性模量和玻璃化转变温度。

Toughening and Reinforcing Polybutylene Terephthalate Nanocomposites by Modified Silica

The dispersion of nano SiO2 particles was improved by using tetraoctylammonium bromide(TOAB) as dispersing agent.SiO2 was successfully modified by grafting polybutylene terephthalate (pCBT)onto the surface. The pCBT nanocomposites containing different contents of modified SiO2 (0.1wt% -2wt%)were prepared via melt mixing and in-situ polymerization process.The samples were thoroughly characterized by SEM,TG,DSC,DMA and tensile tests.The results showed that the degree of crystallinity was gradually increased with the increase of SiO2 con-tent.The Young′s modulus and fracture energy of nanocomposites with 1wt% modified SiO2 increased by 22% and 56%,respectively.In addition,the elastic modulus and glass transition temperature of nanocomposites were also im-proved by adding SiO2 .