Effect of nanolignin and nanocrystalline cellulose on thermal, mechanical, and water barrier properties of starch composites

In this work, a ternary biopolymer composite was obtained by reinforcing the thermoplastic starch (TPS) with nanocrystalline cellulose (NCC), and nanolignin (NL) originated from oil palm empty fruit bunch (EFB). The samples were characterized for optical, thermal, mechanical, and water barrier properties. UV-vis spectrometry and contact angle results revealed a synergistic effect between NL and NCC in improving transparency, UV light barrier and hydrophobicity of the composites. Furthermore, the ternary films showed better moisture absorbance and swelling performance than the neat and binary films. The glass transition temperature (Tg) of the film with 4 wt% of NL and 4 wt% of NCC increased from 40 to 61 °C compared to the neat film. In addition, the tensile strength was found to be approximately 150% higher than the neat film. This work suggested that incorporating NL and NCC into the starch composites could be a promising alternative to current packaging material with improved mechanical strength, thermal stability, water, and UV light barrier performance.