Rich-Syndiotacticity of Poly(Ethyl Methacrylate) Prepared by Modified Microemulsion Polymerization.

Nanoscale poly(ethyl methacrylate) (PEMA) particles were prepared by a monomer post-added microemulsion polymerization procedure. ¹H NMR analysis suggested that the PEMA samples were rich in syndiotactic content (58-64% rr) and lower in isotactic content (4-6%mm). The glass transition temperatures (Tg's) of the products were also higher than those of the PEMA samples prepared by ordinary free-radical polymerization. The polymer properties, such as particle size, molecular weight, tacticity, and Tg were affected by the reaction conditions. The smaller the particle size, the higher the syndiotacticity, the lower the isotacticity, the greater the molecular weight, then the higher the Tg of PEMA. A possible mechanism of rich-syndiotacticity was also discussed primarily. [ABSTRACT FROM AUTHOR]