A fluorine-free approach for fabricating superhydrophobic coatings on bamboo using methyltrimethoxysilane (MTMS) under alkaline conditions

Abstract

To address growing global concerns about wood safety, a novel strategy has been developed to replace wood with bamboo, taking advantage of its abundant availability and sustainable potential. To reduce the natural hydrophilicity of bamboo, a superhydrophobic material was synthesized through a one-pot sol-gel process using methyltrimethoxysilane (MTMS). This method simplifies the preparation of superhydrophobic coatings by eliminating the need for additional micro- and nano-particle additives or modifications with other low surface energy materials. Under alkaline conditions, MTMS promotes the in-situ formation of a three-dimensional micro- and nano-scale structure on the bamboo surface via a straightforward impregnation process that simultaneously imparts low surface energy to the substrate. The chemical reaction between MTMS and the bamboo surface forms strong covalent bonds, resulting in a water contact angle of 155.4° and a sliding angle of 2.3°. Moreover, the NH₄OH@MTMS@bamboo composite exhibits exceptional durability under harsh conditions, including exposure to moisture, dirt, and intense ultraviolet radiation. This cost-effective, eco-friendly, and efficient preparation method offers significant potential for industrial-scale applications.