甲基丙烯酸-2-羟丙酯/苯乙烯分散共聚合的研究

采用梳型结构分散剂，对亲水性单体甲基丙烯酸－2－羟丙酯（HPMA）的分散聚合进行了研究。通过反应在不同结构分散剂存在下表现的不同的动力学特征，提出了反相微悬浮成核机理。并通过HPMA与共聚单体苯乙烯（St)分散共聚合动力学规律的研究，证实了这种成核机理的存在。认为亲水性单体HPMA的分散聚合存在两种机理，均相成核机理和反相微悬浮机理，当采用F－1分散剂时倾向于遵循反相微悬浮成核机理。而且共聚单体苯乙烯，反应比例越小越倾向于反相微悬乳机理，当采用F－2分散剂时反应倾向于均相成核机理，而且苯乙烯单体共聚的引入，使聚合速率变快，有利于提高体系的稳定性。

Study on Kinetics of Dispersion Polymerization of 2-Hydroxypropyl Methacrylate

In the present work, the dispersion polymerization of 2-hydroxypropyl methacrylate (HPMA) was carried out by using comb-structure polymer as dispersant. According to the different features of reaction kinetics resulted from different structure of dispersing agents, all inverse mini-emulsion nucleation was proposed, and it was verified through the kinetic study of copolymerization with comonomer styrene. Furthermore, it was suggested that the dispersion polymerization of HPMA have two mechanisms, i.e. homogeneous nucleation and inverse mini-emulsion nucleation. When using F-1 as the dispersant, the dispersion polymerization of HPMA foIlows the inverse mini-emulsion nucleation. In this case the lower the styrene content in the system, the more likely the reaction tend to follow the inverse mini-emulsion nucleation. However, the reaction will obey the homogeneous nucleation when the dispersant F-2 is used. In addition, the introduction of comonomer styrene will quicken the reaction rate and make the reaction system more stable.