采用电导法、紫外光谱法、GPC和电子显微镜等方法对甲基苯乙烯和苯乙烯的无乳化剂乳液聚合进行了较为详细的研究。探讨了这两种单体在无乳化剂乳液聚合初期的引发成核机理，比较了它们在无乳化剂乳液聚合时的异同。甲基苯乙烯的无乳化剂聚合机理与苯乙烯类似，即采用胶束成核机理聚合。但是，由于甲基苯乙烯有较低的活化能和链增长速率常数，使其在聚合初期有较高的转化率和更加显著的水相终止。所以在相同的条件下，甲基苯乙烯比苯乙烯有较大的胶乳粒子尺寸。

Controlled synthesis of aldehyde-functional poly(methystyrene) (PMS) latexes in an emulsifier-free system was achieved via an emulsifier-free emulsion polymerization of methylstyrene using V-50 as an initiator, followed byanin-situ surface oxidation catalyzed by copper(Ⅱ) chlorideandtert-butyl hydroperoxide. Our investigation of the effect of oxidant concentration, reaction time, and temperature demonstrated that controlling the surface concentration of aldehyde and carboxylic acid groups was readily accomplished by altering these three reaction parameters. The concentration of the catalyst, however, was found to have little affect on the rate of oxidation. Furthermore, the amounts of surface aldehyde and carboxylic acid groups were determined by conductometric and potentiometric titrations. Electrolyte stability of functionalized latexes was also examined with regard to their critical coagulation concentrations in various salt solutions. Finally,SEMstudies were conducted and clearly showed that surface morphology of functional latexes hardly altered with a low degree of oxidation but became aggregates when highly oxidized latexes were formed.

methylstyrene.PMS. latex particles in an emulsifier-free emulsion were first synthesized by using 2,29-azobis-2-amidinopropane. dihydrochlorideV-50. as an initiator. Purification of the latexes by dialysis was followed inorder to remove residual monomer, initiator and electrolytes. The cationic polymethylstyrene. latexes were then oxidized in the presence of t-butyl hydroperoxide catalyzed by copper chloride at 608C under air. The degree of oxidation increased with reaction time, but the emulsions of highly oxidized poly methylstyrene. latexes were found to be unstable. An increase of oxidant concentration enhanced the rate of oxidation, while the catalyst concentration had little influence on it. The effect of reaction temperature and pH value on the catalytic oxidation of poly methyl-styrene. latexes was also investigated.