Renewable corn straw-based lignocellulose-mimetic films with tailorable functional properties

Efficiently valorizing agricultural straws to fabricate high-value-added materials is a scientifically and technologically significant research direction. In this work, corn straw (a typical lignocellulosic agricultural straw) was directly utilized with nanocrystalline cellulose from it acting as both an adhesive and reinforcing phase, to prepare corn straw lignocellulose (CSLC)/polybutylene adipate-co-terephthalate (PBAT)/polyvinyl alcohol (PVA) nanocomposite films in the N,N-dimethylacetamide/lithium chloride (DMAC/LiCl) dipolar aprotic solvent system. The preparation included two steps: controlled partial dissolution of corn straw in DMAC/LiCl, followed by the complete dissolution of introduced PBAT and PVA via precise parameter modulation. In the composites, undissolved corn straw-derived nanocrystal domains served as the reinforcing phase, while dissolved lignocellulosic fractions acted as an adhesive and part of the matrix. This structural design produced homogeneous, transparent pale beige nanocomposite films. High corn straw loading notably improved the interfacial compatibility between the PBAT/PVA matrix and lignocellulosic components, endowing the composites with excellent tensile properties-those with 50 wt% corn straw exhibited a tensile strength of 6.7 MPa and an elastic modulus of 4.4 MPa. Overall, this study develops a facile, low-cost and scalable strategy to convert renewable biomass into high-performance value-added materials, which has great practical application potential in relevant fields.