Superhydrophobic Materials Based On Silicone Combustion Product

Superhydrophobic materials have many practical applications in the fields of self-cleaning, anti-icing, anti-fogging, oil-water separation and etc. The keys of preparing superhydrophobic surface are constructing micro-nano hierarchical structure and modifying it with low surface energy materials. Due to the excellent properties of elasticity, thermal stability and insulation, organic silicone rubber is widely used in numerous high performance products. However, the present methods of recycling silicone are limited. In this work, we utilized the smoke particles and residues from the silicone combustion to fabricate superhydrophobic coatings and explored appropriate preparation methods. Besides, the prepared superhydrophobic materials were applied to separate oil-water mixture. The work provides a new approach to recycling silicone.By smoke deposited method, the smoke particles from silicone combustion process were used to prepare superhydrophobic silica/silicone composite coating, which shows a water contact angle higher than 160°and a sliding angle lower than 1°. The nanoparticles agglomerates formed and fixed on the silicone to construct dual-scale rough morphology, endowing the surface superhydrophobicity with excellent stabilities of heat, water impact and water immersion.After the silicone combustion product was powdered, they were hot-pressed into the PP substrate and superhydrophobic composite coating was obtained, exhibiting a high water contact angle (>150°) and a low sliding angle (3.5°). The amount of powder and hot-pressing time have an influence on the morphology and superhydrophobicity of the composite coating. The abrasion resistance of the composite coating was also studied. Conductive superhydrophobic composite coating can be prepared by introduced Ketjen black into the silicone.The superhydrophobic silica/silicone composite coating on copper mesh substrate can be applied in separating oil-water mixture, achieving high separation efficiency of over 90% for various organic solvents and diesel. The silicone combustion product was used to fabricate oil-absorbing bag possessing rapid absorption. The absorbed oil can be recycled by distillation or utilized through burning, which also refreshed the initial properties of the combustion product. A device connecting the oil-absorbing bag and vacuum system for continuous separating oil-water mixture was also constructed.