摘要
采用向种子乳液中连续滴加预乳液的方法制备了大粒径(约1μm)核壳型PBA/PMMA乳胶粒,经透射电镜和光散射粒径分析仪测试乳胶粒子的微观结构和粒径分布,结果显示乳胶粒的微观形貌确实为核壳结构,粒径接近微米级,粒径呈高斯分布并且相对分布较窄.将此类乳胶粒干燥后用于PVC改性,考察了粒径对共混物力学性能的影响,其中粒径在500 nm左右时的ACR具有较好的增韧效果.
Latex particles of up to 1μm can be made by standard emulsion polymerization methods.In this work,it is shown that use of an oil-soluble initiator AIBN) provides a means by which large(1?μm) polybutyl acrylate/polymethyl methacrylate latex particles can be made by squential core-shell polymerizations.It is suggested that the limited water solubility of AIBN decreases the formation of secondary particles and that the lower ionic strength of the water phase enhances stability of the latex compared to a conventional persulfate initiator.To further minimize formation of secondary particles,long reaction times and progressively larger proportions of seed latex are used in successive reactions.Transmission electron microscope(TEM) study indicates that ACR latex particles have a regular core-shell structure obviously.The exact particle size distributions were determined with a particle size analyzer and are shown to be Gaussian about means and relative narrow distribution.The ACR were used as the modifier for PVC.The results showed that the impact strength of the modified PVC with ACR particle of 0.5?μm were better than that of others.
出处
《云南大学学报(自然科学版)》
CAS
CSCD
北大核心
2005年第S3期511-515,共5页
Journal of Yunnan University(Natural Sciences Edition)
基金
河北省重大攻关资助项目(01213074D)
河北省教育厅资助项目(2004420)
关键词
聚氯乙烯共混改性
乳液聚合
聚丙烯酸酯树脂
核壳型乳胶粒
力学性能
blending modification of PVC
emulsion polymerization
ACR resin
core/shell latex particles
mechanical properties