편광현미경을 이용한 PTT/PTN 블렌드의 등온결정화 거동 분석

Abstract

Isothermal crystallization behaviors of poly(trimethylene terephthalate) (PTT), poly(trimethylene naphthalate) (PTN), and PTT/PTN blends were analyzed using a polarizing microscope equipped with a hot-stage. As the melting time at 260oC of PTT/PTN blends increased, the crystallization proceeded slowly due to the copolymer formation which resulted from the ester interchange reaction at the elevated temperature. PTT and PTT-rich blends formed spherulites over the temperature range of experiment, but PTN formed spherulites only at lower crystallization temperatures such as 150oC. PTN and PTN-rich blends formed distorted spherulites at high temperatures such as 180oC, which seemed to result from the b-crystal formation of PTN at that temperature. The radial growth rate of the spherulite formed during the crystallization was obtained by the measurement of radii of the spherulites. The radial growth rate decreased as PTN content in the blends increased.