Tacticity, molecular weight, and molecular-weight-distribution relationships in stereoregular polyacrylonitrile prepared by electron beam irradiationcanal polymerization

The preparation and characterization of stereoregular isotactic polyacrylon itrile (PAN) by electron beam (EB) irradiation on a urea canal complex are described. The EB method has several advantages over the ordinary gamma-ray irradiation method: a very short polymerization time is needed (within a f ew seconds) and EB irradiation is carried out intermittently, and so all th e polymer properties can be studied as a function of the EB irradiation dos e. The structure-properties relationships of PAN, such as intrinsic viscosi ty versus the number-average molecular weight and the viscosity versus the isotacticity range were clarified. Significant information for the optimiza tion of the tacticity of PAN was extracted.