Effects of processing conditions on flexural properties of cellulose nanofiber reinforced “green” composites

Environmentally-friendly “green” composites were fabricated from starch-based, dispersion-type biodegradable resin and cellulose nanofibers. Dispersion-type biodegradable resin and cellulose nanofibers were blended well using a home-use mixer and a stirrer; the mixture was then dried in air or in vacuum. Composites were hot-pressed at 140 °C and 10–50 MPa. Their flexural strength and flexural modulus increased with increasing molding pressure. They were also affected by preparation methods and conditions. Their mechanical properties such as strength and modulus showed good correlation with their density. Especially, it is apparent that the stirrer mixing process is effective, yielding enhanced uniform dispersion of nanofibers.