悬浮聚合法制备SiO2气凝胶-聚苯乙烯复合材料

PREPARATION OF SiO2 AEROGEL-POLYSTYRENE COMPOSITE BY SUSPENSION POLYMERIZATION

采用悬浮聚合的方法制备了SiO2气凝胶-聚苯乙烯复合材料,研究了SiO2气凝胶添加量对复合材料在合成过程中的聚合时间、聚合度、分子量及其分布的影响,以及对复合材料的Tg、高温稳定性等性能的影响。结果表明,随着SiO2气凝胶含量的增多,聚合反应时复合材料的聚合时间增长,单体转化率下降;GPC测试表明,随着SiO2气凝胶添加量的增加,数均分子量减低,且PDI有所增加,同时平均粒径增长迅速;DSC与TG测试表明,玻璃化转变温度与初始分解温度逐渐升高,失重速率有所降低。

Silica aerogel-polystyrene composites were prepared by suspension polymerization.The effects of silica aerogel addition on the polymerization time,polymerization degree,molecular weight and distribution of the composites were studied.The influence on the properties such as Tg and high temperature stability of the composite was also investigated.The results show that with the increase of silica aerogel content,the polymerization time of the composite increases during polymerization,and the monomer conversion rate decreases.The GPC test shows that the number average molecular weight decreases and PDI increases with the addition of silica aerogel.In the mean time,the average particle size increased rapidly.The DSC and TG tests showed that the glass transition temperature and the initial decomposition temperature gradually increased,and the weight loss rate decreased.