Abstract
The influence of γ-irradiation on the structure and some mechanical properties of poly-β-hydroxybutyrate was studied. Specimens of PHB were γ-irradiated with various doses (1–20 Mrad) in air and vacuum. The molecular weight, structural characteristics of the crystalline and amorphous phases, characteristics of thermal degradation, and deformation of the polymer were determined. The crystallinity was found to increase with increase in the radiation dose and with the corresponding reduction in molecular weight. The increase of crystallinity was the greater the smaller the length of macromolecules (higher radiation dose). The melting temperature T m , which characterizes the crystalline order, decreased with decrease in the molecular weight. The results of calorimetric studies suggest that radiation-caused degradation, which occurs at a temperature at which “cold” crystallization (60°C) is possible, might also affect the crystalline part of the polymer.
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Institute of Polymer Materials, Riga Technical University, Riga, LV-1048, Latvia. Translated from Mekhanika Kompozitnykh Materialov, Vol. 35, No. 2, pp. 239–252, March–April, 1999.
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Bibers, I., Kalnins, M. Control of biopolymer poly-β-hydroxybutyrate characteristics by γ-irradiation. Mech Compos Mater 35, 169–178 (1999). https://doi.org/10.1007/BF02257247
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DOI: https://doi.org/10.1007/BF02257247