甲基丙烯酸3-三甲氧基硅丙酯在乳液体系中的分配

PARTITION OF 3-TRIMETHOXYSILYL PROPYL METHACRYLATE IN EMULSION POLYMERIZATION SYSTEM

通过气相色谱(GC)研究了甲基丙烯酸3_三甲氧基硅丙酯(MPS)在乳液体系各相中的分配行为,并测得了MPS在各种情况下的分配系数.发现当MPS加入量达到聚合物种子的约10 wt%时,体系进入饱和状态,且大部分MPS分配在粒子相中.通过对单体相分配行为的理论分析,并结合实验数据,发现种子乳胶粒粒径、聚合物种子中的化学组成对MPS的分配行为影响很小,而温度则使MPS在各相中的饱和浓度增加.

By the emulsion polymerization process, organic polymers carrying functional groups have been involved in the elaboration of the hybrid latex in order to imporve the chemical bonding between the organic and inorganic components. The organic-inorganic hybrid nanoparticles have been synthesized using 3-trimethoxysilyl propyl methacrylate （MPS） by this method in our previous work. In the emulsion polymerization process of MPS and styrene, the partition of MPS in each phase of the emnlsion not only influenced the free radical polymerization rate and the chemical composition of the copolymer, but also influenced the hydrolysis-condensation ractions of SiOR groups in MPS. The emulsion stability and the organic-inorganic hybrid microstructures largely depended on it also. In this paper, the MPS partition behavior is characterized by gas chromatography （GC）, and the partition coefficients are also measured. It is found that the system becomes saturated when the MPS amount is about 11 wt% of polymer seeds, and most MPS are parted in the polymer phase. Through theoretical analysis and experimental approving, it was found that the MPS partition behavior didn＇ t change with the particle size and chemical composition of polymer seeds, and the saturated concentrations of MPS in each phase were increased with the temperature.