Crystallizability of a biodegradable polymer as a criterion for assessing the degree of influence of the aquatic environment on its structure

Abstract

The work is devoted to the study of the effect of an aqueous medium on a polymeric biodegradable material based on poly-3- hydroxybutyrate (PHB) by differential scanning calorimetry (DSC). To analyze the structural reorganizations of the polymer, we studied the effect of an aqueous medium on the process of polymer crystallization after soaking in distilled water. It is shown that after exposure to water, the forms of crystallization exotherms change, the rate of polymer crystallization decreases, and the heat of the process decreases insignificantly. To analyze the kinetics of non-isothermal crystallization, we used the kinetic crystallization parameter G [deg/min], which characterizes the rate of polymer crystallization in the non-isothermal mode. It has been established that the crystallizability of PHB decreases after exposure of the samples. The observed dependence of the parameter G on the scanning rate indicates a decrease in the mobility of polymer chains, a decrease in their flexibility after exposure to an aqueous medium, which is a consequence of a change in their structure.