Innovative production of lignin nanoparticles using deep eutectic solvents for multifunctional nanocomposites

A green and simple lignin nanoparticles (LNPs) production strategy was developed using deep eutectic solvents (DES). The LNPs were formed with corncob alkali lignin by sequential DES dissolution and self-assembling pro-cess. Uniform size and spherical shape of LNPs were observed by scanning electron microscopy (SEM), transmis-sion electron microscopy (TEM), dynamic light scattering (DLS), zeta potential analyzer and gel permeation chromatography (GPC). Less than 100 nm of LNPs were formed, and these particles were preserved without sig-nificant size-increase or precipitation within 30 days. The nanocomposite films prepared by incorporating the LNPs into biodegradable poly(vinyl alcohol) (PVA) matrix display good mechanical properties (tensile strength of 82.5 MPa and breaking strain of 103.3%), excellent UV-blocking (100% shielding of the UV spectrum region), strong hydrophobicity (static contact angle of 117.0 degrees) and relatively high thermal stability (the maximum ther-mal weight loss temperature increased by 40 degrees C). Overall, this study not only facilitates the advancement of lignin-based nanotechnology by DES but also paves the way for the PVA polymer composites as potential food and medical packaging materials. (c) 2021 Published by Elsevier B.V.

Automated summary

A green and simple lignin nanoparticles (LNPs) production strategy was developed using deep eutectic solvents (DES), forming uniform size and spherical LNPs from corncob alkali lignin. Incorporating LNPs into biodegradable poly(vinyl alcohol) (PVA) matrix resulted in nanocomposite films with excellent mechanical properties, UV-blocking, hydrophobicity, and thermal stability. This study not only advances lignin-based nanotechnology by DES, but also opens up possibilities for using PVA polymer composites as food and medical packaging materials.