Reverse atom transfer radical polymerization (ATRP) of n-butyl methacrylate was conducted in an aqueous dispersed system. Using a water-soluble initiator (V-50), a nonionic surfactant (Brij 98), and a hydrophobic ligand (dNbpy) to complex a copper halide, polymers with relatively well controlled molar masses and low polydispersities wen: obtained. Stable latexes with particle diameters within 150-300 nm were formed. Kinetic studies were performed under various experimental conditions. The influence of the concentrations of the catalyst, the surfactant, and the initiator as well as the temperature on the polymerization rate, molecular weight, and particle size was investigated. Because of the lack of high molecular weight polymer during the early polymerization stage, reverse ATRP in the aqueous dispersed system presumably has a different nucleation mechanism from that of a conventional emulsion polymerization. In addition, fast decomposition of the initiator prevents the continuous entry of radicals into the particles from the aqueous phase. As a result, the kinetics of the reverse ATRP is fundamentally different from a classical emulsion polymerization and is controlled mainly by the atom transfer equilibrium.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据