Highly wear-resistant and recyclable paper-based self-lubricating material based on lignin-cellulose-graphene layered interwoven structure

Conventional paper-based wear-resistant materials employ thermosetting resin as the matrix, which are difficult to recycle, degrade, and reuse after scrapping, causing significant damage to the environment. The discovery of sustainable alternatives has the potential to transform the manufacture of paper-based wear-resistant materials into low-carbon production. Herein, inspired by spider webs sticking to insects, a paper-based self-lubricating material based on lignin-cellulose-graphene layered interwoven structure was prepared by lignin-cellulose assisted in-situ exfoliation of flake graphite strategy. Graphene adheres to the interlaced cellulose network, while lignin serves as a natural binder and matrix, resulting in a 2D interwoven structure. The paper-based film had a 37.4% greater average mechanical strength than pure lignin-cellulose film and a 56% lower toughness loss following heat treatment. The friction coefficient of the film-15% was 173.3% lower than that of the film-10%, and it maintained long-term stability with a low wear rate of 3.9 × 10−3 mm3/(N·m). Furthermore, the end-of-life products were recycled five times and can be degraded by microorganisms in moist soil within 40 days. The degradation products can provide nutrients for plant growth, indicating that it is a potential alternative to non-recyclable wear-resistant materials for light-duty transmission machinery.