Syndiotactic polymerization of methyl methacrylate

Typical Ziegler‐type catalysts derived from AIR 3 and TiCl 4 were found to be effective in the syndiotactic polymerization of methyl methacrylate at low temperatures. The influences of polymerization variables on the polymer yield, the molecular weight of the polymer produced, and the syndiotactic regulating capacity of the catalysts were investigated. In general AlEt 3 /TiCl 4 molar ratios of 3:10 mixing of both the catalyst components and aging of the catalyst system in the temperature range of −30 to 30°C. using aromatic hydrocarbon solvents such as toluene as a polymerization medium, and low polymerization temperature, such as −78°C. are the preferred conditions for the formation of syndiotactic, high molecular weight poly(methyl methacrylate) in high yield. From the results of testing catalyst activities of the separated catalyst systems it was concluded that some cooperation between AIR 3 and the insoluble Ti halide compound obtained by the reduction of TiCl 4 with AIR 3 is essential for the formation of syndiotactic poly(methyl methacrylate).