Kuniharu Nagakubo

Preparation of polyamides having 2-phenyl-4,5-imidazolediyl units in the main chain

Abstract Polyamides having 2-phenyl-4,5-imidazolediyl units in the main chain were prepared from 4,4′-2-phenyl-4,5-imidazole)dibenzoic acid and aromatic diamines. Polycondensation by a direct solution method gave high-molecular-weight polymers. The polymers are highly soluble in polar solvents and show high T g (> 290°C) and T d (> 440°C) values. Films were cast from dimethylacetamide or 1-methyl-2-pyrrolidone solutions. Mechanical properties, i.e. tensile strength, elongation at break and tensile modulus, were evaluated.

Synthesis and photodegradation of copolyamides containing α-diketone linkage in the main chain

Abstract Copolyamides were prepared from 4,4′-dichloroformylbenzil, adipyldichloride and hexamethylenediamine. The melting points and solubilities of the copolyamides varied with benzil content. The copolyamides were irradiated by u.v. light in solution and in a film. The copolyamide irradiated in solution was still soluble but the copolyamide irradiated in a film was crosslinked. The mechanisms of the photochemical reactions are discussed.