DETERMINATION OF AVRAMI EXPONENT BY DIFFERENTIAL SCANNING CALORIMETRYFOR NONISOTHERMAL CRYSTALLIZATION OF POLYMERS

A novel approach was developed to study the non-isothermal crystalliza tion kinetics of polymers based on the Ozawa equation. The method dete rmines the Avrami exponent, n, using exclusively the data confined to the primary crystallization regime. It was applied to a selection of e leven semicrystalline polymers including some biodegradable polyesters . The differential scanning calorimetry exotherms were obtained from t he cooling rates covering 2 to 40 K min(-1). As noted, poly(-caprolact one) and nylon 6,10 resulted in the lowest and highest n, being equal to 1.5 and 5.1, respectively. The present findings on n were compared with those reported in the Literature. Their morphological implication s were also discussed. (C) 1998 Elsevier Science Ltd. All rights reser ved.