One-step compatibilization of poly(lactic acid) and tannin via reactive extrusion

The compatibility issue between poly(lactic acid) (PLA) and tannin is a big challenge for preparing PLA/tannin biocomposites with enhanced properties. In this work, composites with enhanced properties have been accomplished using an efficient one-step reactive extrusion method with the help of methylene diphenyl diisocyanate (p-MDI) or 3-aminopropytriethoxysilane (APS). The extent of compatibility achieved via the one-step was evaluated by tensile, morphological, rheological, and thermal properties. The obtained results indicated that the adhesion promoters, especially p-MDI, contributed efficiently to an improved tensile behavior of the resulting composites with a tough tensile-fracture surface compared with incompatibilized PLA/tannin composite. Moreover, these composites displayed a plateau-like rheological behavior, enhanced complex viscosity, higher melting and thermal degradation temperature. This approach can be potentially adapted to other PLA/biopolymers composite systems. (C) 2020 The Authors. Published by Elsevier Ltd.