微波合成SiO_2气凝胶核/聚苯乙烯壳微球研究

Researching on microwave synthesize of SiO_2 aerogels core/polystyrene shell microsphere

将水玻璃为硅源所制备的纳米孔硅气凝胶与苯乙烯单体用微波加热合成法制备出SiO2气凝胶核/聚苯乙烯壳复合微球.用顺序间隔取样测试方法试验复合微球的密度、转化率和包覆率与微波合成温度、时间和聚合体系各组分变化情况,分析讨论了影响变化因素和原因.通过TEM和FE-SEM对复合微球进行结构与形貌表征.结果表明,优选体系组分配比为SiO2气凝胶3g、苯乙烯21g、乙醇水溶剂配比为380g∶20g、引发剂4.2g及稳定剂2g,微波合成工艺参数为加热功率500W,加热时间40min、加热温度60℃.在此工艺条件下合成,复合微球合成转化率是67.1%、包覆率为32.7%,制备出的核壳结构复合微球的粒径约为100～200nm、震实密度为0.353g/cm3,且表面凹凸不平状似＂草莓＂的微粒.

The water glass as silicon source of the nanoporous silica aerogel with styrene monomer by microwave heating were prepared from SiO2 aerogel nuclear/polystyrene shell composite microspheres.Using sequential interval method to test the density of the composite microsphere,conversion rate and encapsulation with the change of microwave synthesis temperature,time and the component of polymer system.Analyzes and discusses the factors and reasons of the change.Characterize the structure and morphology of the composite microsphere through TEM and FE-SEM.The results show that the system is preferred ratio of SiO2 airgel group assignment 3g,styrene 21 g,ethanol aqueous solvent ratio of 380g∶20g,initiator 4.2g and stabilizer 2g,microwave synthesis process parameters heating power 500 W,heating time 40 min,the heating temperature 60℃.Synthesis under these conditions,the composite microspheres synthesis conversion rate is 67.1%,covering rate is 32.7%,core-shell composite microspheres prepared by the particle size of about 100～200nm,jolt density is 0.353g/cm3,and the uneven surface like a＂strawberry＂particles.