核壳型苯丙胶乳的制备及其成膜性研究

Preparation of Styrene-Co-Butyl Acrylate Latex with Core-Shell Morphology and Study on the Latex Film Structure

以苯乙烯、丙烯酸丁酯和二乙烯基苯为单体,通过间歇-半连续细乳液聚合,制备不同交联度的核壳型胶乳。分别采用激光粒度仪和透射电镜测定了不同聚合阶段胶乳的粒径大小、分布和形态。并用场发射扫描电镜考察胶乳膜液氮淬断制得的断面形貌。结果表明,随着聚合阶段深入,胶乳粒径变大,聚合过程未发生二次成核;乳胶粒具有核壳结构;随交联剂二乙烯基苯浓度的提高,膜中初始乳胶粒的形态越加明显,膜的连续性下降,交联结构抑制聚合物链在乳胶粒间的扩散,破坏膜结构的连续性。

A series of latex with core-shell morphology is prepared by a batch-semibatch two stage miniemulsion polymerization technology.The crosslinking degree of the latex is controlled by the concentration of the crosslinker in the feeding stream.The constant number of particles demonstrates the absence of secondary nucleation throughout the polymerization.The core-shell morphology is proved by Transmission Electron Microscopy（TEM） analysis.And,the cross-sectional morphology of the resulting latex film is studied by Field Emission Scanning Electron Microscopy（FESEM）.It is found that the continuity of the film decreases greatly with the increase of the crosslinking degree,and the initial particles are more obvious.