Lu He,Gege Bao,Xi Yu,Xiaofeng Zhang,Xiaobei Jin,Zixuan Yu,Rong Zhang,Daochun Qin
Bamboo is a sustainable structural material with excellent mechanical properties, but its high flammability and hygroscopicity restrict industrial utilization. This study develops a synergistic dual-modification approach using sodium silicate mineralization and hydrophobic treatment to enhance flame retardancy, mechanical strength, dimensional stability, and mold resistance. Compared to untreated bamboo, the modified bamboo exhibited 50.9%, 21.0%, 64.1%, and 16.7% reductions in peak heat release rate, total heat release, peak smoke production rate, and total smoke release, respectively. The Limiting Oxygen Index reached 36.0% with a Fire Performance Index of 1.4. Hydrophobic treatment reduced water absorption by 84.5% and thickness swelling by 52.2% (longitudinal), 52.0% (radial), and 57.6% (tangential), achieving a 147° water contact angle. Mechanical properties improved significantly, with modulus of elasticity and modulus of rupture increasing by 15.3% and 9.2%, respectively. Mold growth was completely inhibited under high humidity conditions. This strategy overcomes key limitations of bamboo in flammability, moisture sensitivity, and mechanical performance while preserving sustainability, thereby demonstrating significant potential for fire-safe construction and engineered biocomposites.
The complex and demanding marine environment poses significant challenges for concrete coatings. Despite the exceptional properties, superhydrophobic coatings have encountered limitations such as complex preparation processes and limited structural stability, thus impeding their widespread application. In this study, we employed molecular monomers to simultaneously conduct in-situ silica mineralization and silane hydrolysis reactions on mortar substrate. The mineralized product, nano-silica, effectively fills microcracks and pores, serving as an internal reinforcing agent. Simultaneously, the silica is utilized to construct a robust and dense micro-nano hybrid structure. The results in the preparation of a silica mineralized layer with exceptional mechanical strength on the surface. The in-situ hydrolysis of silane introduces a low surface energy for hydrophobic modification, leading to the formation of a stable superhydrophobic coating with a contact angle of 157°. Mineralized structure and hydrophobic surface offer both internal and external protective effects. This one-step approach promotes the complete hybridization of hydrophobic silane groups with the three-dimensional silica matrix. During the in-situ reaction process, the hydrolyzed silane molecules bond with the surface of silica microspheres , significantly enhancing the integrity and stability of the coating structure . Notably, even after multiple cycles of peeling and abrasion, the coating surface maintains its hydrophobic properties, further emphasizing its durability. The results demonstrate that this coating enhances both the structural and chemical performance of cement-based materials, paving the way for the expanded application and development of superhydrophobic coatings in the marine concrete industry.
危险品化学品经营许可证（带存储）