Engineered polysaccharide alpha‐1,3‐glucan in highly filled thermoplastic polyurethane systems

Abstract This study explores the use of α‐1,3‐glucan, which can be produced through an enzymatic polymerization process, as additive for thermoplastic polyurethane composite systems. Most importantly, highly filled thermoplastic polyurethane composites can be achieved with up to 80% by weight polysaccharide content. Analysis of mechanical properties demonstrates that strength and modulus can be significantly improved, while the plasticizer content allows for adjustments of compound flexibility. The addition of 60% α‐1,3‐glucan increased the flexural modulus of the thermoplastic polyurethane by 497% while adding 80% α‐1,3‐glucan increased the flexural modulus by 3193%. Citrate esters can be incorporated as plasticizer to improve processibility and flexibility of the compounds. An increase in impact strength of 55% was achieved when 10% of tributyl citrate was added to the 80% α‐1,3‐glucan composite. Based on the compatibility and property enhancements, the use of these engineered polysaccharides may provide additional options for producing sustainable composite materials with high renewable content and unique properties.