Preparation And Comprehensive Properties Of Hydrophobic Composite Fabrics Based On Modified Silica

In order to solve the problems of poor spinnability,brittleness and poor hydrophobicity of inorganic silica based fiber,and to objectively evaluate the comprehensive properties of modified silica based hydrophobic composite fabric.In this paper,the sol-gel method was used to introduce silane coupling agent vinyl triethoxysilane(VTES)into tetraethyl-orthosilicate(TEOS)to prepare spinnable hydrophobic silica sol.Electrospinning method was used to deposit the sol fiber on the substrate to prepare hydrophobic composite fabric.In order to improve the mechanical properties and formability of silica-based hydrophobic composite fabric,Polyurethane(PU)was used as the mechanical support of hybrid fibers for spinning,and the style differences between fluorine-containing and fluorine-free hydrophobic composite fabrics based on PU were explored.The main factor evaluation and fuzzy comprehensive analysis of the fabrics were carried out to objectively evaluate the comprehensive performance differences and influencing factors of different types of fabrics.The specific content is as follows:(1)With TEOS and VTES as silicon source precursors,spinnable hydrophobic silica sol was prepared.Combined with electrospinning technology,controllable preparation of Si O₂ based hydrophobic composite fabric was realized.The influence mechanism of VTES content on hydrophobic properties,mechanical properties and fabric style of composite fabrics was discussed.The experimental results show that when TEOS:VTES=1:0.6,the composite fabric has the best performance,the water contact Angle is 139.3°,the air permeability is 133.15mm/s,and the longitudinal tensile fracture strength is 1256.3 N and 989.1 N,respectively.(2)In order to further improve the brittleness of Si O₂-based fiber,PU/Si O₂composite fabric was prepared by introducing polyurethane as mechanical support.The experimental results show that the tensile fracture strength of the composite fabric increases by 12.3%,and the formability of the composite fabric increases from 0.48 to0.56 mm²,making it easier to prepare clothing.(3)Based on FAST fabric style instrument,fabric style comparison of fluorine-free and fluorine-containing polyurethane fabrics was carried out,the relationship between fabric style and various test indicators was explored,and 5 main factors affecting fabric performance were obtained,covering 92.738%of the original data information.The relationship between the main factor and the fabric style was established,and the comprehensive score of the fabrics was calculated and sorted.Among the fluorinated fabrics,the fabric style ranked the best when PU/FPU=10:5.Among all polyurethane fabrics,PU/Si O₂=12:2 has the best formability.(4)Fuzzy matter-element method was used to evaluate the comprehensive properties of composite fabrics.The coefficient of variation method was used to determine the weight of each index objectively,and the Euclidian degree of closeness was established to evaluate the comprehensive properties of composite fabrics.The results show that the comprehensive performance of PU/FPU=14:1 and PU/Si O₂=12:2is more than 0.5,so the comprehensive performance is better.