Thermal behavior of amide substituted diacetylenes

Abstract

Abstract Diacetylenes substituted with various amide groups were prepared and their solid‐state polymerization behavior was studied. A calorimetric study of the isothermal polymerization of 1,6‐diacetylamino‐2,4‐hexadiyne was performed in detail. This compound has an extremely high reactivity. The reaction proceeded very quickly and the ultimate conversion reached over 40% slightly above room temperature. The feature of the reaction resembles those observed in the solid‐state polymerization of other diacetylene compounds, i.e., the reaction proceeds slowly in the initial stage, but the rate of reaction increases drastically at about 5% conversion to polymer. Quantitative conversion, however, was not attained at any temperature, and the reaction leveled off within 1.5 h. It is assumed that the reaction cannot continue owing to the distortions generated in the crystals during the polymerization process. The crystalline state of the polymer obtained was highly disordered.