STRUCTURE AND PROPERTIES OF POLY(NAPHTHOL YNEIMIDOBENZIMIDAZOLE) POLY(QUINAZOLONOBENZIMIDAZOLE) BLOCK-COPOLYMERS

The structures of poly(naphtholyneimidobenzimidazole) and poly(quinazo lonobenzimidazole) and their block copolymers and blends were studied using light and electron microscopy and X-ray scattering. These materi als display heterogeneous structure and a uniform distribution of anis otropic elements. Mechanical and dielectric relaxation studies of the initial and thermally treated films of homopolymers and block copolyme rs reveal that the low-molecular-mass impurities significantly affect the occurrence of relaxation processes; high molecular mobility is obs erved both at low and high temperatures. Large-scale molecular mobilit y in a wide temperature range usually associated with beta'-relaxation was also suggested. The films examined show very high stability in th ermomechanical testing. By varying the length of the blocks, it is pos sible to obtain materials with high stress-strain and elastic properti es.