Effects of thermoplastic elastomers on mechanical and thermal properties of glass fiber reinforced poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) composites

This study investigates the effects of thermoplastic elastomers on the mechanical and thermal properties of glass fiber reinforced bacterial polyester, poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) (PHBH), composites. The thermoplastic elastomers used were styrene‐ethylene‐butylene‐styrene copolymer (SEBS) and maleated styrene‐ethylene‐butylene‐styrene copolymer (SEBS‐MA). Composites were prepared by melt‐compounding and injection molding. Mechanical test results suggested that SEBS‐MA was more effective than SEBS in improving ductility, fracture energy, and notched Izod impact strength of glass fiber reinforced PHBH composites. Scanning electron microscopy results suggested that SEBS‐MA encapsulated fibers as well as dispersed in the PHBH matrix, whereas SEBS dispersed in the PHBH matrix without fiber encapsulation. Differential scanning calorimetry results suggested that both SEBS and SEBS‐MA addition decreased the degree of crystallinity of the PHBH matrix in glass fiber reinforced PHBH composites. POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers