Study On Preparation Of Oleophobic Nylon Fabric And Sponge And Its Oil-water Separation Performance

The frequent occurrence of oil spills at sea and the random discharge of domestic water have a serious impact on the ecological environment and human health.Special wetting materials have attracted wide attention because of their good selectivity and high separation efficiency for oil-water mixtures.In this paper,several oil-water separation materials were designed for different oil-water mixtures and oil-water emulsions.Firstly,kaolin and guar gum composite coatings were constructed on the surface of nylon fabric in order to make the surface have certain roughness and adhesion,and then perfluorononanoic acid was used to reduce the surface energy of modified nylon.Nylon fabric with superhydrophilic / oleophobic property in air was obtained.The highest contact angle of the nylon fabric to oil is 149 °.It has good corrosion resistance and the separation efficiency for different oil-water mixtures is more than96%.Secondly,the composite coating of nano-silica and polydopamine was constructed on the surface of cotton fabric,combined with the low surface energy of perfluorononanoic acid,the modified cotton fabric with super oil-repellent property in air was prepared.The contact angle of the modified cotton fabric is as high as 164.5 °.After 25 cycle experiments,the oil-water separation efficiency is still up to 97%.The separation efficiency of the mixture of corrosive solution and oil can also be as high as 96%.In addition,the modified fabric has good surface mechanical properties.Finally,using polyurethane foam as the basic skeleton,cellulose powder was dissolved and regenerated in the skeleton,and the cellulose / polyurethane composite foam with underwater super-hydrophobic property was obtained.The composite foam can separate the mixture of toluene,kerosene,gasoline,petroleum ether and n-hexane with water,and the separation efficiency can be maintained above 97%.Most importantly,the resulting foam can also effectively separate water-toluene and water-kerosene water-in-oil emulsions.It has certain resistance to corrosive liquids.The composite foam can also effectively separate the water containing methylene blue dye,which shows a wide application prospect in the field of water treatment.