| Polytetrafluoroethylene(PTFE)-polyphenylene sulfide(PPS) composite coating mesh film was successfully prepared by a spray-plasticizing method on the stainless steel mesh. These composite coating mesh films show super-hydrophobic and super-oleophilic properties. Contact angle of this mesh film is 156.3°for water,and close to 0°for diesel oil and kerosene. The contact angle hysteresis is about 4.3°(5μL droplet) for water.The surfaces of the prepared PTFE-PPS composite coating mesh films were analyzed through scanning electron microscopy(SEM).It is shown that lots of particles with microscale accumulate on the surface of the mesh film and on these particles find reseaus of nanometer scale.It was analyzed by Wenzel model that the micro- and nanostructures on the surface of mesh film could enhance hydrophobicity and oleophilicity of the surface.Surface micro- and nanostructures is the key to PTFE-PPS composite coating mesh films with super-hydrophobicity and super-oleophilicity.Performance of PTFE-PPS composite coating mesh films was studied in some aspects, such as the water and oil droplets' behaviors on the mesh films,the effects of the mesh films being immerged in different solutions on the super-hydrophobicity and super-oleophilicity, the pencil hardness,flexility and the adhesive force of the mesh films.It is shown that PTFE-PPS composite coating mesh films have the characters of super-hydrophobic, super-oleophilic,high hardness,strong adhesive force,better flexility and corrosion resistance, which lay a foundation for application of these mesh films.According to the two extreme properties of super-hydrophobicity and super-oleophilicity, PTFE-PPS composite coating mesh films were used to separate oil and water.A simple oil/water separation device with many stages was designed to investigate the separation ability of the prepared mesh films.The retentate separated by the mesh film was analyzed through extraction-uv spectrophotometer.In the experiment,the effects of the state of oil in the water,initial oil content,pore diameter of the stainless steel mesh substrate and separation stages of the mesh film on the separation effect were studied.The results show that PTFE-PPS composite coating mesh films are only used for the separation of the floating oil at present.The more initial oil content,the higher oil removal rate;the smaller pore diameter of the stainless steel substrate,with the increase of separation stages of the mesh film,the less oil content in the retentate and higher oil removal rate. PTFE-PPS composite coating mesh films on the 400 meshes/inch(0.038 mm) stainless steel mesh were used to design two oil/water separation devices respectively.And the separation effect of the two oil/water separation devices was investigated.The results show that the separation effect of the improved device is stabler than that of the initial device;the smaller flow rate,the less oil content in the retentate and higher oil removal rate.The oily feed containing 16.9 wt%(about 163.7 g/L) is separated by the improved device to 20 mg/L.
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