Preparation And Application Of Organic-Inorganic Composite Superhydrophobic Nanometer Coatings

Superhydrophobic surfaces have been widely used in waterproofing,self-cleaning,drag reduction,selective absorption,electrochemistry,etc.The biomimetic study on the surface self-cleaning property of lotus leaves shows that the perfect hydrophobicity is derived from the synergistic effect of the dual micro-structure and nano-scale combination and the low surface energy materials covered on the surface.To simulate the structure of lotus leaves,researchers have tried many methods,including sol-gel method,plasma etching,phase separation and templating,etc.However,these methods are not only complicated but also expensive,which are not convenient to prepare a large number of superhydrophobic materials in the actual production and life.Therefore,it is more meaningful to seek a simple and inexpensive preparation method.Superhydrophobic coating and superhydrophobic film are simple and easy ways to widely use superhydrophobic surface.In this paper,hydroxylated multi-wall carbon nanotubes(HMWCNTs) with good physical and chemical properties were used as raw materials to prepare coatings with good superhydrophobic and superoleophilic properties,which provided a certain method for the application of superhydrophobic surfaces in practice.First,the hydroxylated carbon nanotubes(HMWCNTs) were modified by one-step solvent synthesis to obtain almost completely superhydrophobic and superoleophilic nanopowder.Then the HMWCNTS @MTMS prepared above were mixed into the ordinary industrial coatings with a certain quality ratio,and the modified superhydrophobic coatings were obtained.By investigating the effect of different proportion of HMWCNTS @MTMS added into the coating on the morphology and hydrophobicity of the final coating and analyzing the stability of the coating surface,the optimal use ratio of such additives and coatings was found out,and the superhydrophobic coating were skillfully obtained.It is worth pointing out that the modified coating has excellent strength and adhesive force of the tradiional coating and greatly improves the mechanical properties of the superhydrophobic coating.We put the best ratio of paint spray on the surface of metal,glass,wood,metal mesh,etc.,the cured film can be given excellent superhydrophobic and superoleophilic characteristics.The contact angles(CA)of water and oil on the coated surface are 170 o and close to 0 o,respectively.Due to the superhydrophobic and superoleophilic characteristics and excellent stability of the superhydrophobic and superoleophilic coating prepared in this work,we attempted to spray the modified coating with the optimal ratio on the surface of the copper mesh for oil-water separation.After the test,the contact angles(CA) of water and oil on the coated surface of the copper mesh are about 165 o and 0 o,respectively.We use the copper mesh separated different types of oil-water mixture and experimental results showed that the network has high separation efficiency(> 96%) and can be recycled,which provides a simple method for the preparation of oil-water separation membrane.