Interaction between thermoplastic starch and cellulose in poly (butylene adipate-co-terephthalate) composites with cellulosic fillers

Abstract

Starch and cellulose being both carbohydrate polymers, thermoplastic starch (TPS) is expected to be a suitable compatibilizer for materials made of cellulosic fillers and polyesters. This paper investigates the interactions between TPS and cellulose in Poly(butylene adipate-co-terephthalate) (PBAT), melt-blended composites. For this, microfibrillated cellulose (MFC) were dispersed in a commercially available polymer (Mater-Bi, MB), containing TPS already dispersed in PBAT. Microscopic observations were performed on composites based on either MB or neat PBAT reinforced with microfibrillated cellulose (MFC). Tensile tests and dynamic mechanical analysis in solid and in the molten state revealed a percolating network of fillers. Results indicated interaction between TPS and cellulose as the origin of the adhesion of the components but also of biphasic agglomerates.