Compatibilité de polymères porteurs de groupements amides tertiaires avec le poly(difluoro‐1,1 éthylène). Etude par enthalpimétrie différentielle

Abstract

Abstract The miscibility of poly(1,1‐difluoroethylene) ( 1 ) with poly( N ‐vinyl‐2‐pyrrolidone) poly( N ‐methyl‐ N ‐vinylacetamide) and poly( N , N ‐dimethylacrylamide), containing tert ‐amido groups, was investigated by differential scanning calorimetry. Amorphous homogeneous blends were obtained whenever the weight fractions of polymer 1 is less than 0,7. The dependence of the single glass transition temperature ( T g ) versus composition may be readily analyzed either through the Gordon‐Taylor equation (high values of the k parameter, suggesting strong specific interactions between the homopolymers) or by means of the Couchman relation (no adjustable parameter). The broadening of the glass transition range and the variation of the increment of specific heat at T g for the blends are discussed.