A SAXS Study of PHB/DGEBA Blends Crystallized at Different Temperatures
A small-angle X-ray scattering (SAXS) study of blends of poly-3-hydroxybutyrate (PHB)/diglycidyl ether of bisphenol A (DGEBA) with weight ratios of 90/10, 70/30 and 50/50 and PHB isothermally crystallized at temperatures between 60ºC and 120ºC for one hour was performed. PHB was studied at different temperatures between 30ºC and 140ºC. The scattering curve results (intensity as a function of scattering vector (q)) indicated a main peak and secondary peaks associated with the thickness of the lamellae of PHB (with a strong tendency to crystallization). The position of the main peak decreased when the temperature was increased. At high temperatures (~120ºC), a deformation was observed in the main peak and a secondary peak was superimposed. This secondary peak was associated with the lamellar structures formed during the re-crystallization process. The results are discussed based on the DGEBA inclusion in the blends, crystallization temperature and partial interlamellar segregation.