中空聚合物微球的制备——种子及核乳胶粒的制备  

Preparation of Hollow Latex Particles——Preparation of Seed and Core Particles

作　　者：袁才登[1] 曹建伟[1] 缪爱花[1] 曹同玉[1] 

机构地区：[1]天津大学化工学院高分子科学与工程系,天津300072

出　　处：《高校化学工程学报》2006年第4期576-582,共7页Journal of Chemical Engineering of Chinese Universities

摘　　要：为了制得具有中空结构的聚合物微球,首先以十二烷基苯磺酸钠(SDBS)为乳化剂,在其用量低于CMC的条件下,进行甲基丙烯酸甲酯(MMA)、甲基丙烯酸(MAA)和丙烯酸丁酯(BA)的乳液聚合,制备了带羧基的种子乳胶粒。然后采用MMA、MAA和二乙烯基苯为单体进行种子乳液聚合,制备了轻度交联的带羧基的核乳胶粒。该核乳胶粒经过核-壳乳液聚合和适当的碱处理工艺就可成为具有中空结构的聚合物微球。采用粒度仪测定了乳胶粒的直径及其分布,采用TEM对乳胶粒结构形态进行了表征。研究了种子及核乳胶粒制备过程中单体加料方式、乳化剂用量及羧基单体种类等因素对聚合稳定性、乳胶粒直径及其分布以及最终的中空聚合物微球结构形态的影响,确定了制备种子及核乳胶粒的最佳工艺条件。在制备种子阶段,SDBS用量为单体总量的0.5%,采用一次性加入单体的进料工艺;在核乳胶粒制备阶段,以MAA为羧基单体,所有单体采用“饥饿式”加料,半连续补加乳化剂并使乳化剂用量为核单体总量的0.15%时可保持聚合稳定性并保证无新乳胶粒生成。For preparing the hollow polymer particles, seed latex particles with carboxylic group were synthesized via emulsion polymerization by using methyl methacrylate （MMA）, butyl acrylate （BA） and methacrylic acid （MAA） as comonomers. The sodium dodecyl benzene sulfonate （SDBS） was used as emulsifier and its dosage used was lower than its critical micelle concentration （CMC）. The seeded emulsion copolymerization of MMA, MAA and divinyl benzene was carried out by using the prepared carboxylated latex particles as seeds, so that the lightly crosslinked core particles with more carboxylic groups were prepared. Hollow polymer particles can be obtained by core-shell emulsion polymerization on the base of the core particles and then by alkalization treatment of the core-shell latex particles. The diameters and their distributions of latex and hollow particles were determined by nanosizer. The particle morphology was also characterized by TEM. The effects of the ways of monomer feeding, emulsifier dosage used and kinds of carboxylated monomer used on the polymerization stability, seed and core diameters and their distributions were studied. The optimal conditions for preparing seed and core latex particles were obtained as follows. During seed forming stage, the SDBS dosage used is 0.5%（wt） of total monomer and the monomer mixture is fed in one batch. During the core forming stage, MAA is used as carboxylic comonomer, and the monomer mixture is fed in a starved feeding fashion, the supplementary emulsifier is fed in a semi-continuous fashion and its dosage used is 0.15%（wt） of the total monomers to ensure the polymerization stability and monodispersity of the obtained seed and core particles.

关 键 词：中空乳胶粒 乳液聚合 核壳乳胶粒 乳胶粒形态 

分 类 号：O632.5[理学—高分子化学] TQ316.334[理学—化学]