Temperature influence on changes of parameters of the unit cell of biopolymer PHB

Abstract

The changes of parameters of the unit cell of biopolymer poly(/3-hydroxybutyrate) (PHB) during heating from room temperature to the melting temperature are measured and results are presented here. The considerable increase of value of parameter a with increase of temperature is noticed with coefficient of thermal expansion of (≈ 1.4 ± 0.3) × 10-4°C-1. In the same time the changes of parameters b and c are negligible. On the basis of wide-angle X-ray scattering diffractograms the coefficient k is determined to be 1.06 ± 0.08 (Hermans-Weidinger method).