Mechanically durable, superhydrophobic, and flame-retardant wood fabricated via hierarchical hybrid solution impregnation

Abstract

The preservation of traditional wooden structures and the demands of modern architectural interior decoration continue to drive an urgent need for wood modification technologies that impart anti-fouling, self-cleaning, flame-retardant, and thermal insulation properties. However, the limited mechanical and physical durability of functional coatings has hindered the development of next-generation functional wood. This study addresses these challenges by developing a novel multifunctional modification strategy for commercial wood boards. Through a combination of delignification and the impregnation-deposition of micro–nano organic–inorganic hybrid building units, a wood sample with enhanced self-cleaning and flame-retardant properties was fabricated. After impregnation treatment, the wood sample exhibited excellent hydrophobic and anti-fouling characteristics, with water and oil contact angles reaching 160° and 155°, respectively. Multiple stability tests demonstrated that the coating retained its superior hydrophobic and anti-fouling performance even under harsh conditions, including mechanical abrasion, repeated cleaning, and chemical corrosion. Furthermore, the impregnated wood sample displayed outstanding thermal insulation performance, with a temperature reduction of up to 59.9% compared to untreated wood, along with excellent flame retardancy and self-extinguishing properties. In summary, this innovation overcomes two major challenges in functional wood technology, preventing the loss of functional components and extending the service life of functional wood, providing a scalable, high-performance wood composite solution for applications in green building, historical preservation, and safety-critical infrastructure.