Facile synthesis of mechanically flexible and super-hydrophobic silicone aerogels with tunable pore structure for efficient oil-water separation

Silicone aerogels are promising in efficient thermal insulating and oil absorbent materials due to the low density, low thermal conductivity, and unique micro -/nano-porous structure. However, poor mechanical reliability and water repellency along with the complicated processing greatly hinder their potential applications in emerging fields. Herein, we report a lightweight, wide-temperature mechanically flexible and surface super-hydrophobic silicone aerogels with tuned cross-linked network via a facile ambient drying process. Poly (methylhydridosiloxane) (PMHS) with different hydrogen contents was utilized to react with vinylmethyldimethoxysilane under Pt catalyst via hydrosilylation reaction and thus tune the cross-linking network in silicone aerogel effectively. The optimized PMHS-based silicone aerogels as -prepared exhibit a low density of 70-150 mg cm(-3), good mechanical reliability in both liquid nitrogen and high-temperature condition of 200 degrees C, excellent compressive resilience after 100 cyclic compressions, and outstanding surface water repellency with water contact angle of similar to 165 degrees and water sliding angle of <3 degrees. As expected, such multi-functional PMHS aerogels show a better thermal insulating performance than the commercial polymer foam materials. Furthermore, the as-prepared silicone aer-ogels not only display outstanding absorption capacity for both floating and sunken oil/solvent but also demonstrate excellent continuous oil/water separation efficiency. Clearly, the versatile PMHS-based aerogel prepared in this work may provide a new route for the design and development of high-performance silicone aerogel materials. (C) 2022 Elsevier Ltd. All rights reserved.