Investigation of the mesomorphic structure of p-alkoxy-phenyl-p-acryloyloxy benzoate polymers

Polymers were prepared from the phenyl and p-alkoxy-phenyl esters of p-acryloyloxy benzoic acid. These polymers resulted in anisotropic systems during the cooling of their melt or on concentrating their solutions. The anisotropic polymers had a Schlieren texture. On the basis of small- and wide-angle X-ray scattering the polymers are identified as non-crystalline, the diffuse reflections are related to their molecular dimensions. By GPC in sym-trichloro benzene a broad distribution of molecular dimensions was observed where the number average molecular dimension corresponded to that measured in bulk. The average degree of polymerization is about the same for the five polymers. The polymer molecules are cylinders of 8–10 nm length and 2.5-3.9 nm diameter, which form the anisotropic state by close packing. The polymer molecule cylinders are made up of aperiodic helices, therefore the nematic state becomes glassy on cooling without formation of any crystalline polymer.