Performance Research Of Multifunctional Switchable Wettability Materials Based On Mineral

In the face of frequent oil leakage accidents,low cost and facile operation of switchable wettability materials stand out from all the oil-water separation materials.The preparation of switchable wettability materials not only requires the construction of micro-nano rough structures and low-surface energy materials on solid surfaces,but also the introduction of switchable wettability responsive functional groups.The reported external stimuli of switchable wetting materials include pH value,gas,electric field,temperature,solvent,magnetic field and light,etc.Because of great surface morphology and special chemical composition designed during the synthesis process,such intelligent responsive materials can effectively and controllably separate water or oil,and protect the surface from oil contamination in the meanwhile.Although great progress has been made in the research of switchable wettability materials,most of the existing switchable wettability materials require expensive heavy metal raw materials or highly toxic modified organic solvents,and the preparation process is time-consuming and requires strict control of temperature and humidity.The most important thing is that these materials are usually limited by the substrate,thus reducing the possibility of practical application of new materials.According to the current research condition,research thought of preparing multifunctional switchable wettability materials are prepared by using the mineral soil particles as raw materials and introducing the responsive polymer for selective modification.The main research content of this paper is divided into two parts:(1)The pH-responsive polymer was synthesized by using 3-(trimethoxysilyl)propyl methacrylate,2-(dimethylamino)ethyl methacrylate and 1H,1H-perfluorooczyl acrylate,and the switchable wettability fabric was prepared by grafting the responsive polymer and cheap quartz sand onto the fabric.The wettability of the material can change between and superhydrophilic/underwater superhydrophobic and superhydrophobic,so the reversible separation of water/light oil and water/heavy oil can be realized by alternating treatment of acid and alkali,and the material has a high oil/water separation efficiency for different water/light oil mixture or water/heavy oil mixture.The modified material still exhibits excellent superhydrophobicity after being worn 140 cm on 600#sandpaper.Even after being soaked in salt solution or exposed to UV environment for a week,the material still exhibits good water-repellent performance.(2)Based on micron-grade brucite and nano-grade titanium dioxide as raw materials,the multifunctional switchable wettability material was finally prepared through the modification of methyl perfluorooctanoate and 3-aminopropyltri ethoxy silane.Different from the previously reported pH-responsive materials,the wettability of this material can be reversibly switched between and superhydrophilic/superhydrophobic and superamphiphobic,so that the controllable separation of oil and water can be realized by alternating treatment of acid and alkali.In addition,this material can be widely used on a variety of substrates,and the modified material shows excellent superamphiphobic after wearing 140 cm on 600#sandpaper.And the material can still maintain good oil and water repellent performance after water drop impact test for 72 h.Moreover,the modified fabric coated with flameresistant coating will not be ignited even if burned by the candle flame.