NONISOTHERMAL CRYSTALLIZATION KINETICS OF THERMOTROPIC POLYESTERS WITH FLEXIBLE SPACERS IN THE MAIN-CHAIN

The non-isothermal crystallization kinetics of two thermotropic polyes ters with flexible spacers in the main chain were studied. The influen ce of the spacer type on the kinetics has been considered. The Ozawa t heory for nonisothermal crystallization was used to analyse the differ ential scanning calorimetry data. The polyester with an oxyethylenic g roup as the flexible spacer followed the Ozawa equation and allowed th e calculation of the Avrami exponent under non-isothermal conditions, but in the case of the polyester with methylenic groups as the flexibl e spacer the Ozawa theory is not valid. (C) 1998 Elsevier Science Ltd. All rights reserved.