Fabrication And Application Of Functional Superhydrophobic Fabrics

With the development of science and technology,new materials with functions such as waterproofing,anti-fouling,anti-bacterial and conductive properties have become a hot research spot.In addition,due to the increasingly serious problem of marine pollution,the preparation of durable oil-water separation materials via simple and efficient methods has also attracted widespread attention.Superhydrophobic surface has been widely used in water repellence,anti-fouling,oil-water separation,ice melting and self-cleaning areas due to its excellent water resistance.At present,the methods of preparing superhydrophobic coating on fabric surface have some disadvantages such as time-consuming process,harsh preparation conditions and the frequent use of expensive fluorine-containing compounds,which limit their application in practical production.In this paper,nanoparticles were introduced on fabric surface to construct roughness,and hydrophobic materials were used to reduce the surface energy of fabric.The as-fabricated superhydrophobic fabrics with different functions were applied in the fields of oil-water separation,self-cleaning,anti-bacterial,ice melting and sensors.The main research contents and results are listed as following:(1)The modified graphene oxide(mGO)was obtained by chemically grafting graphene oxde(mGO)with(3-mercaptopropyl)trimethoxysilane(MPTMS),and the vinyl-terminated polydimethylsiloxane(V-PDMS)was used as low-surface-energy substance,then the graphene-based superhydrophobic fabric was obtained via dipping-UV curing method.The successful modification of GO was confirmed by Fourier transform infrared(FT-IR)spectroscopy,X-ray photoelectron spectroscopy(XPS)and thermogravimetric analyzer(TGA).Scanning electron microscopy(SEM),water contact angle(WCA)measurement and atomic force microscopy(AFM)were ultilized to study the effects of the mass ratio of mGO and VPDMS on the surface morphology and wettability of fabric.The results showed that with the increase of the mass ratio of mGO and V-PDMS,the roughness of the fabric surface significantly increased and the contact angle of fabric increased firstly and then decreaseed slightly.When the mass ratio was 0.25,the WCA of the fabric reached 157°.In addition,the graphene-based superhydrophobic fabric showed excellent thermal and chemical stabilities and could be successfully applied in the field of oil-water separation,exhibiting high separation efficiency and good recyclability.(2)Dopamine(DPA)was used to pretreat pristine fabric by oxidative self-polymerization,and silver particles were formed on fabric surface by in-situ generation method to construct rough structure.The mixture of 1-dodecanethiol(HS(CH2)11CH3)and 11-mercaptoundecanoic acid(HS(CH2)10COOH was ultilized to endow the fabric hydrophobicity and pH responsiveness.It was confirmed that polydopamine,silver particles and mercaptan mixtrure were successfully introduced on fabric surface by XPS,SEM and AFM tests.With the increase of the molar ratio of 1-dodecanethiol in the mixed mercaptan solution,the WCA of the fabric gradually increased.When the molar ratio was 0.7,the as-fabricated fabric exhibited superhydrophobicity under acidic and neutral conditions while superhydrophilicity under alkaline condition.The pH-responsive superhydrophobic fabric showed unique bidirectional oil-water separation ability,high separation efficiency and excellent recyclability.In addition,due to the presence of silver particles,the pH-responsive superhydrophobic fabric demonstrated good anti-bacterial function.(3)The pristine fabric was firstly immersed into the solution of silver nanowires(AgNWs)synthesized by polyol method,and then immersed into the hexane solution of polydimethylsiloxane.After being cured at high temperature,the conductive superhydrophobic fabric was obtained.The successful preparation of AgNWs was confirmed by SEM,UV-vis spectrometer(UV-vis)and X-ray diffractometry(XRD).FT-IR was employed to confirm the successfully introduction of AgNWs and polydimethylsiloxane on fabric surface.The surface morphology,wettability and electrical conductivity of the as-fabricated fabric were studied,and results showed that with the increase of the dipping cycle in AgNWs solution,the roughness,hydrophobicity and conductivity of the fabric gradually increased.The conductive superhydrophobic fabric could be used not only for the efficient separation of oil-water mixtures,but also for ice melting and piezoresistive sensing.