乳液聚合法制备核(二氧化钛)-壳(聚苯乙烯)复合粒子

研究了乳液聚合技术用于聚苯乙烯(polystyrene,PS)包覆改性二氧化钛(TiO2)纳米粒子.十二烷基硫酸钠(sodium dodecyl sulfate,SDS)作乳化剂,考察了其浓度对复合粒子形态的影响.用Fourier红外光谱、透射电镜和热重分析表征了无机-有机核-壳复合粒子.用沉降实验评价复合粒子的分散性和分散稳定性.实验表明:SDS浓度为0.8mg/mL时,可以实现PS对纳米TiO2粒子的成功包覆.最佳条件下,乳液聚合单体转化率达62.0%:包覆效率为54.0%;复合粒子中PS占62.6%;复合粒子平均粒径为181nm.复合粒子能在乙酸乙酯中形成均匀分散体系.

PREPARATION OF CORE(TITANIUM DIOXIDE)-SHELL(POLYSTYRENE)COMPOSITE PARTICLES BY THE EMULSION POLYMERIZATION METHOD

Application of the emulsion polymerization technique to encapsulation of titanium dioxide(TiO2)nano-particles inside polystyrene(PS)latex particles was investigated.Sodium dodecyl sulfate(SDS)was used as the surfactant of emulsion polymerization.The effect of the SDS concentration on the morphdogy of composite particles was discussed in detail.The inorganic-organic core-shell composite particles were characterized by Fourier transform infrared spectrophotometry,transmission electron microscope and thermogravimetric analysis.The dispersibility and dispersion stability of composite particles wcre examined by sedimentation experiments.The most successful encapsulation was achieved with the SDS concentration of 0.8 mg/mL.The results show that the conversion of the monomer is 62.0% in the emulsion polymerization,while the encapsulation efficiency is 54.0%,and the PS is 62.6%(in mass) of the composite particles.The average particle diameter of the composite particles is 181 nm.As expected,a homogeneous dispersion of the composite particles in acetic ether without aggregation was achieved.