Recombination of agricultural residues into moldable composites

Abstract

Increasing efforts have been devoted to developing biobased and biodegradable plastics and composites from lignocellulosic biomass. Current bioplastic production entails multiple challenging steps including monomer production from biomass as well as polymer synthesis and modification. Here, we report a practical recombination strategy to transform agricultural residues into moldable cellulose-reinforced lignin (CRL) composites. The strategy involves deconstruction of biomass particles followed by thermo-compression molding of cellulose fibers and lignin mixtures. The resulting CRL composites demonstrated excellent mechanical and thermal properties as well as water, abrasive, and flame resistance. Mechanistic studies reveal that small particle size, removal of water-soluble fractions, as well as reservation of lignin and its cross-linking reactivity have considerably positive effects on preparation of high-quality composite items. These insights offer a versatile strategy for transforming various types of low-grade biomass, such as corn stover, into eco-friendly and potentially biodegradable or compostable composites that can serve as sustainable alternatives to traditional duroplast materials.