高分子中空微球的制备及其在聚硫密封剂中的应用

摘要

Core-shell structured polymer microsphere fabricated via seeded emulsion polymerization, taking methacrylic acid and methacrylate as nuclear monomer,styrene as shell monomer.Hollow pol-ymer microsphere was prepared using the method of stepwise alkali/acid treatment,nuclear layer that containing rich carboxylic acid was fully ionized and moved away from the microsphereviaswelling. The finial particle size of the hollow microsphere were controlled through adj usting the amount of emulsifier in the seed preparation stage,and two different size of hollow microsphere (551nm and 156nm)were gotten.The polysulfide sealant was prepared by blending the two kinds of microsphere with polysulfide rubber respectively and the property of the sealant was investigated.The structural characteristics,morphology,ingredients and mechanical properties were analyzed by transmission electron microscope (TEM),Fourier infrared spectrometer (FTIR),electronic tensile machine.The results show that hollow microspheres have a uniform distribution of particle size and high degree of hollowness.The addition of hollow polymer microsphere can reduce the density of the sealant,as well as improve mechanical properties.In comparison,hollow polymer microsphere with big size has a bet-ter filling effect.%以甲基丙烯酸及甲基丙烯酸酯类单体为核、苯乙烯单体为壳层,通过种子乳液聚合法合成核壳结构的聚合物微球.采用碱酸分步处理的方法,将富含羧酸的微球内核充分离子化,通过溶胀离开微球,得到高分子中空微球.通过种子制备阶段乳化剂用量的控制可调控最终中空微球的粒径,并获得两种不同粒径的中空微球(分别为551nm和156nm).将两种高分子中空微球分别与聚硫橡胶共混,制备出相应的聚硫密封剂.采用透射电子显微镜(TEM)、傅里叶红外光谱仪(FTIR)、电子拉力机对其结构、形貌、成分及其力学性能进行研究.结果显示:所制备的中空微球粒径分布均匀,中空度较高.添加高分子中空微球可以降低密封剂密度,同时提升其力学性能.相比较而言,粒径较大的高分子中空微球具有更好的应用效果.