TiO2／PBA／PMMA核壳粒子的制备与表征

纳米粒子是热力学不稳定体系，容易发生颗粒团聚。为了更好地改善纳米粒子的分散性,本文报道利用乳液聚合的方法制备以表面处理过的纳米二氧化钛为核丙烯酸丁酯和甲基丙烯酸甲酯为壳的TiO2／PBA／PMMA复合粒子。分析二氧化钛、乳化剂、引发剂、反应温度和超声震荡时间等因素对聚合反应单体转化率的影响，并表征核壳复合粒子。结果表明，利用乳液聚合方法制备的二氧化钛粒子为核壳结构。平均粒径为251nm。其粒径分布较未改性纳米TiO2明显变窄,改善了纳米粒子的分散性。

Preparation and characterization of TiO2/PBA/PMMA core-shell particles

Nano-particles are likely accumulative and the system is thermodynamics unstable.In order to improve the dispersion of nano-particles,TiO_2/PBA/PMMA coreshell composite particles are prepared by emulsion polymerization,with organized titanium dioxide as the core and acrylic ester monomers as the shell.Factors effecting the polymerization rate of acrylic ester monomers are analyzed,such as organized titanium dioxide,monomer proportion,initiator,emulsion,temperature and ultrasonic time.The particles' composition is also observed.The results show that the prepared TiO_2 particles is superior in core-shell structure with an average size of 251 nm.The distribution of modified nano-TiO_2 becomes obviously narrower and dispersion of the nano-particles is improved.