writer：Cai-Li YU, Fa-Ai ZHANG, Xing-Hua ZHU
keywords：emulsion polymerization, kinetics, nano-SiO2, hydroxyl methacrylate
source：期刊
specific source：Polym. Adv. Technol. 2009, 20 347–350
Issue time：2009年

Kinetic of acrylic emulsion polymerization containing hydrophilic hydroxyethyl methacrylate (HEMA) and acrylic acid (AA) in the presence of nano-SiO₂ was investigated. The influence of temperature, emulsifier level, hydroxyl monomer content and the level of nano-SiO₂ on monomer conversion, polymerization rate (Rp) and the particle size was investigated. The results showed that the presence of nano-SiO₂ increased the Rp when the level was below  5% but decreased when the level was above 7.5%, the more levels, the more seriously. As the temperature and emulsifier levels increased, and the presence of hydroxyl monomer, the Rp increased. The active energy of the system was 142.01kJ/mol and the relationship of Rp and the concentration of emulsifier (E) was Rp∝[E]^0.38. The mean particle size increased, particle size distribution became broader as the increase of nano-SiO₂ levels.