Study On The Preparation And Performance Of Water-based Organosilicon Polyurethane Coated Superhydrophobic Fabric

As a flexible functional material,superhydrophobic fabric has excellent application value in the fields of self-cleaning,oil-water separation,anti-fouling,and other fields because of its special wetting properties,so it has been widely favored by domestic and foreign researchers.However,the preparation of superhydrophobic fabrics has disadvantages such as cumbersome conditions and methods,poor durability,and the use of low surface energy compounds containing fluorine,which hinder the practical application of the superhydrophobic fabrics.For this reason,this paper proposed a method for preparing superhydrophobic fabrics with simple process,good stability and environmental friendliness.The main research contents and result were as follows:Firstly,through molecular design,with isophorone diisocyanate?IPDI?,single-ended dihydroxy polydimethylsiloxane?2-PDMS?,3-methoxy-1,2-propanediol as the main raw materials,2,2-dimethylolbutanoic acid?DMBA?as the hydrophilic monomer,trimethylolpropane?TMP?as a crosslinking monomer,and monohydroxy polydimethylsiloxane as a blocking agent,a series of water-based silicone polyurethane?WSiPu?were prepared by a prepolymer method.And the effect of polydimethylsiloxane structure,organ silicone content,DMBA content,TMP content and R value?the molar ratio of-NCO to-OH?on the WSi Pu aqueous dispersion and the film were explored.The average particle size,storage stability,surface tension of WSiPu aqueous solution,wetting and water resistance of WSiPu film were systematically studied.The optimal conditions for synthesizing WSiPi are determined as follows:the content of silicone is 70%,the content of DMBA is 5%,the TMP content is 1%,the R value is 1.2.And the overall performance of WSi Pu prepared is the best under these conditions.At the same time,the structure of the target product was characterized by FTIR and TGA analysis,which was consistent with the expected results.Then,the micro-nano rough structure was constructed on the surface of the polyester fabric by alkali etching.And the effects of alkali treatment temperature,alkali treatment time and alkali treatment concentration on the etching degree of the polyester fabric were explored.The morphological structure of the polyester fabric was observed by SEM and AFM,and the mechanical strength of the polyester fabric was tested by a universal testing machine.The optimal process conditions for alkali etching of the polyester fabric are determined as follows:alkali treatment temperature is 90?,alkali treatment time is 60 min and the alkali treatment concentration is 3mol/L.Finally,the prepared WSiPu aqueous solution was sprayed onto the surface of the polyester fabric with rough structure by alkali etching,so as to prepare a safe,harmless and durable superhydrophobic fabric.The static water contact angle?WCA?of the prepared superhydrophobic fabric is 153°.In the meantime,the tensile test,friction resistance test and chemical solvent resistance test showed that the superhydrophobic fabric prepared in this experiment has good tensile strength,mechanical stability and chemical durability.Through the oil absorption test under water,the fabric's adsorption of oily substances and the oil-water separation experiment,the results showed that the separation efficiencys of the superhydrophobic fabric are over 99%in various types of oil-water mixture system,and the permeation flux is above 15000 L·m²·h^-1.Thus it can be seen that the superhydrophobic fabric prepared by this method was expected to be applied in the field of oil-water separation.