丙烯酸类中空聚合物粒子的制备与电泳性能

Preparation and Electrophoretic Display of Acrylic Hollow Latex Particles

以甲基丙烯酸甲酯、丙烯酸丁酯、α-甲基丙烯酸和苯乙烯为单体,以过硫酸钠为引发剂,温度控制在78℃,搅拌速度为800 r/min,采用半连续加料法,经乳液聚合分别制得了种子、核及具有核壳结构的聚合物粒子。用动态光散射(DLS)、原子力显微镜(AFM)、扫描电镜(SEM)测得其平均粒径分别为72.1、400及500 nm。核壳粒子用w(NaOH)=10%的水溶液进行溶胀,得到的粒子经透射电子显微镜(TEM)显示为中空结构,在SEM下观察,其平均粒径在900 nm左右。用微电泳仪测得,该中空粒子在四氯乙烯分散介质中电泳淌度为0.004 98 s2.mA.kg,Zeta电位为0.032 2 mV,在水分散相中,Zeta电位为-43.880 mV。

The seed polymer, the core and the particles with core-shell structure were prepared by emulsion polymerization at 78 ℃ with methyl methacrylate, butyl acrylate and methacrylic acid as the monomers and sodium persulfate as the initiator stirring at 800 r/min. Their diameters were 72. 1,400 and 500 nm respectively, as measured by DLS, AFM and SEM. Then hollow particles for electrophoretic display were produced by swelling the core-shell particles with 10 wt% sodium hydroxide solution. The resulting particles have the hollow merphology with average grain size of 900 nm as checked through TEM and SEM. Zeta potentials of the hollow latex particles made by this method in perchloroethylene and in distilled water were 0. 032 2 mV and 0.004 98 mV respectively.