Preparation And Property Of Underwater Superoleophobic Coating

The underwater superoleophobic surfaces have attracted great research interest due to its promising applications in the manipulation of microfluids,anti-bioadhesion materials,water-oil separation,self-cleaning and so on.Hydrophilic chemical composition and rough micro-nanoscale hierarchical structure are the key factors for the construction of underwater superoleophobic surface.However,currently available underwater superoleophobic coating preparation method has the following disadvantages:process complex and costly,thus severely limiting the widespread use of underwater superoleophobic coatings.The underwater superoleophobic coatings are prepared of PNIPAm,polycarboxybetaine and polydopamine（PDA）as hydrophilic materials respectively by constructing roughness structure.The details are as follows:（1）P（NIPAm-co-TMSPMA）was synthesized successfully with NIPAm and 3-Meth-acryloxypropyltrimethoxysilane（TMSPMA）as functional monomer,Tetrahydrofuran as solvent and azobisisobutyronitrile（AIBN）as initiator by free-radical co-polymerization,the polymerizationconditionsofP（NIPAm-co-TMSPMA）havebeenoptimized.P（NIPAm-co-TMSPMA）/SiO₂ was successfully synthesized by sol-gel method.P（NIPAm-co-TMSPMA）/SiO₂coatingwaspreparedbydip-coatingmethod.P（NIPAm-co-TMSPMA）and P（NIPAm-co-TMSPMA）/SiO₂ coating were characterized by means of FTIR、¹H-NMR、GPC、TGA、SEM and contact angle measurement.The experimental results indicated that the underwater oil contact angle was 156°at 30wt%SiO₂,which own excellent underwater superoleophobicity and protein resistance.（2）P（CBMAE-co-TMSPMA）was synthesized successfully with CBMAE and TMSPMA as functional monomer,methanol-isopropanol mixtures as solvent and AIBN as initiator by free-radical co-polymerization,the polymerization conditions of P（CBMAE-co-TMSPMA）have been optimized.P（CBMAE-co-TMSPMA）/SiO₂ was successfully synthesized by sol-gel method.P（CBMAE-co-TMSPMA）and P（CBMAE-co-TMSPMA）/SiO₂ coating were characterized by means of FTIR、GPC、TGA、SEM and contact angle measurement.The experimental results indicated that the underwater oil contact angle was 168°at 30wt%SiO_2,after hydrolysis in a solution hydroxide solution,poly（cationic carboxylate）transformed into poly（carboxybetaine zwitterionic）,the underwater oil contact angle was 174°,which own excellent underwater superoleophobicity,anti-bacterial adhesion and anti-platelet adhesion ability.（3）P（CBMAE）was co-deposited with dopamine（DA）to decorate steel meshes,P（CBMAE）/DA-modified meshes were characterized by means of FTIR、GPC、TGA、SEM and contact angle measurement.The result indicates that the underwater oil contact angle was163°when mass（DA）:mass（PCBMAE）=1:1,which own excellent underwater superoleophobicity,solution stability,mechanical stability and oil/water separation;The separation efficiency remains high after 25 times use（94%for diesel/water mixture）,which own excellent repeatability stability.