Chitin Fiber from Mushroom as Reinforcement for Biobased Polymer

Abstract

This project aimed to study the reinforcement effect of fungal chitin at different loading on chitin/PLA composite. The chitin nanofibers were extracted from three mushroom species (oyster mushroom Pleurotus ostreatus, shiitake mushroom Lentinula edodes, enoki mushroom Flammulina velutipes) and used as a reinforcement element in PLA. The chitin/PLA composite was fabricated using a solvent-casting method followed by the hot-compress molding method. In the solvent-casting method, the chitin nanofibers were dispersed in PLA/chloroform mixture and the mixture was left for solvent evaporation. The solvent-free chitin/PLA thin film was then filled in dog bone mold before proceeded with hot-compress molding at 190°C and 70 bar. The samples with different chitin loading were tested with tensile test to study the mechanical performance of nanocomposite. The chitin/PLA composite from oyster mushroom shows the optimum result (σ= 43 MPa, E= 12 MPa) at 5% chitin loading. The increment of the chitin loading leads to a decrease in both strength and strain. However, for the samples from enoki and shitake mushrooms, the optimum chitin loading is 10% with 55 MPa and 56 MPa tensile strength, respectively. This study suggests the potential of fungal chitin as reinforcement in PLA.