Crystallization and thermal behaviour of poly (d(−) 3-hydroxybutyrate)/poly(epichlorohydrin) blends

doi:10.1016/0032-3861(93)90220-5

Polymer

Volume 34, Issue 5, March 1993, Pages 996-1001

https://doi.org/10.1016/0032-3861(93)90220-5 Get rights and content

Abstract

Atactic poly(epichlorohydrin) (PECH) was blended in a wide range of ratios with poly(D(−)3-hydroxybutyrate) (PHB) isolated from Alcaligenes eutrophus cultures. The crystallization and thermal behaviour of PHB/PECH blends were analysed by d.s.c. and microscopy. All blends show a single glass transition temperature, whose value is dependent on composition, in good agreement with the theoretical values calculated by the Fox equation. The influence of blend composition on the overall crystallization rate and on the spherulite growth rate suggests that the two components form a miscible blend in the amorphous phase. The equilibrium melting temperature decreases with blending; the negative value of the χ₁₂ parameter of the PHB/PECH system suggests that the two components can form a miscible mixture which is thermodynamically stable above the equilibrium melting temperature. The reorganization phenomenon of PHB crystals after first melting was also observed.

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Polymer paperCrystallization and thermal behaviour of poly (d(−) 3-hydroxybutyrate)/poly(epichlorohydrin) blends

Abstract

Polymer

Polymer

Polymer

Polymer

Ann. Inst. Past.

J. Mater. Sci.

Bull. Am. Phys. Soc.

J. Polym. Sci. A2

Polymer

J. Polym. Sci., Polym. Phys. Edn

Polymer paper
Crystallization and thermal behaviour of poly (d(−) 3-hydroxybutyrate)/poly(epichlorohydrin) blends