Composites of poly(lactic acid)/poly(butylene adipate-co-terephthalate) blend with wood fiber and wollastonite: Physical properties, morphology, and biodegradability

Poly(lactic acid) (PLA) was first melt blended with five weight percentages (10-50 wt %) of poly(butylene adipate-co-terephthalate) (PBAT) on a twin-screw extruder and then injection molded. The blend at 30 wt % PBAT exhibited the highest impact strength and elongation-at-break without phase inversion. The 70/30 (w/w) PLA/PBAT blend with high toughness improvement was selected for preparing both single and hybrid composites using an organic filler, wood fiber (WF) and inorganic filler, wollastonite (WT) with a fix total loading at 30 parts per hundred of resin (phr) throughout the experiment. Five WF/WT (phr/phr) ratios for the composites were 30/0, 10/20, 15/15, 20/10, and 0/30. The prepared composites were investigated for the mechanical and thermal properties, melt flow index (MFI), morphology, flammability, water uptake, and biodegradability as a function of composition. All the composites showed a filler-dose-dependent decrease in the impact strength, elongation-at-break, MFI, and thermal stability, but an increase in the tensile and flexural modulus, tensile and flexural strength, antidripping ability, and water uptake compared with the neat blend. The addition of WF and WT was also found to promote the biodegradability of the PLA/PBAT blend. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47543.