Influence of the polymerization temperature on the stereoregularity of radical poly(phenyl methacrylate)

The dependence of the tacticity of radical poly(phenyl methacrylate) upon polymerization temperature has been examined by NMR spectroscopy. Bernouillian statistics were confirmed for polymerization temperatures between 30 and 80°, but slight deviation was found for elevated temperatures (100°). The calculated values of differential enthalpies and entropies of activation for isotactic and syndiotactic propagations revealed that poly(methyl methacrylate) radicals grow more easily in syndiotactic placement than poly(phenyl methacrylate) radicals.