Preparation And Properties Of POSS Based Superhydrophobic Materials

Superhydrophobicity is a unique wetting property of the material surface,and the water droplets remain spherical on the super-hydrophobic surface.Polyhedral oligomeric silsesquioxane(POSS),as a functional nanomaterial with excellent thermal stability,mechanical properties,low surface energy and reactivity,shows unique advantages in many fields.Using POSS as the core material for the preparation of superhydrophobic materials,different "durable" superhydrophobic materials were prepared by a simple process,and their functional applications were discussed.The work of this paper mainly includes the following contents:(1)Octapropyltrimethoxypolyhedral oligomeric silsesquioxane(OTPOSS)and 1H,1H,2H,2H-perfluorooctyltrimethoxysilane(FAS)were used as monomers,POSS-FAS composite nanoparticles were successfully synthesized by sol-gel method.By adjusting the mass ratio of OT-POSS and FAS,different nanoparticles were prepared,and their formation mechanism was analyzed: the hydrolysis and condensation between OTPOSS formed silicon core,and FAS and OT-POSS hydrolyzed monomers further reacted with it to form nanoparticles.Using POSS-based nanoparticles as coatings,a superhydrophobic surface was prepared by spraying method with a maximum contact angle of 156.6°.The superhydrophobic surface was ablated,and the hydrophobic properties were further improved,showing excellent non-wetting properties,with a contact angle of 165.4° and a rolling angle of 0°.(2)Using POSS-based nanoparticles(POSS-FAS)as superhydrophobic functional materials and polydimethylsiloxane(PDMS)as binders for fixing nanoparticles,POSS-FAS/PDMS superhydrophobic coatings were prepared.The adhesion and fixation of PDMS were optimized by controlling the experimental variables.Due to the adhesion of PDMS,the coating can be applied to different substrates(glass,aluminum,cotton fabric).The coating remains super hydrophobic after water impact or sandpaper wear,and POSS also gives the coating good acid and alkali resistance and UV resistance.In addition,the coating has self-cleaning performance,antifouling performance and enhanced buoyancy performance.(3)The hydrophobic cotton fabric with contact angle of 144.9 °was prepared by in-situ grafting of γ-mercaptopropyltrimethoxysilane(MPTTS)and cyclohexyl epoxy oligomeric silsesquioxane(G-POSS)onto cotton fabric.Because POSS combines with cotton fabric by covalent bond,modified cotton fabric exhibits excellent durability,including wear resistance,washing resistance,acid and alkali resistance,organic solvent resistance and UV resistance.In the oil-water separation experiment,the modified cotton fabric shows high separation efficiency;in addition,under adverse conditions,the modified cotton fabric still maintains excellent oilwater separation ability,which is expected to be used as a reliable separation and filtration material in real life.