Preparation and properties of binary green blends from poly(butylene succinate-co- adipate) and β-(1,3)-D-glucan ester derivative

Propionate-hexanoate mix ester of paramylon (PaPrHe), a bio-based β-(1,3)-d-glucan photosynthesized by Euglena, was blended with poly(butylene succinate-co-adipate) (PBSA) and analysed for its physical properties. The morphology of the blend was revealed using a combination of selective enzymatic etching and SEM. The morphology changed from phase separated to co-continuous and then uniform dispersion with increasing PBSA content. In particular, the 10% PaPrHe loading had a unique sub-micron level dispersion with a median particle diameter of 0.6 μm. This ratio also had the highest toughness (67.3 kJ/m2) among all the ratios, surpassing even neat PBSA (53.2 kJ/m2). X-ray analyses of thermally stretched films showed high degree of orientation (94%) and crystallinity in the PBSA rich blends, leading to a 160–400% increase in the tensile strength. All the blend ratios had high thermal stability and melt-processability making the PBSA/PaPrHe green blend a sustainable alternative for packaging and mulch-film applications.