Mechanical and thermal properties of biocomposite films produced from hazelnut husk and polylactic acid

This study focused on the potential use of hazelnut husk (HH) flour, agricultural by-product, as filler in the PLA biocomposite films. The tensile strength and elongation at break of the biocomposites films decreased with the increasing content of the HH flour. As the amount of the HH flour in the PLA was increased by 10 wt%, the tensile strength decreased from 33 to 26.3 MPa. A sharp decrease in the tensile strength (6.33 MPa) of the specimens was determined as the amount of the HH flour was increased by 20 wt%. There was no significant difference in the tensile strength as the HH content increased from 20 to 40 wt%. The main reason for the lower tensile strength was mainly attributed to them due to the weak interfacial bond between HH flour with higher polar surface and the PLA with lower polar surface. The hydrophilic nature of the HH leads to a tendency for HH fibers to mingle or form agglomerations, which resulted in the lower tensile strength, especially at high HH filler loadings. The increase in the filler content improved the thermal stability of biocomposites.