Preparation Of UV-Curable Fluorinated Polyphosphazene Coating And Its Application In Electrical Insulation And Nylon Fabrics

Polyphosphazene is a kind of organic/inorganic hybrid polymer with phosphorus-nitrogen as the inorganic backbone structure.Unlike traditional carbon backbone polymers,polyphosphazenes have a unique phosphorus-nitrogen backbone structure.This structural feature gives them more excellent heat resistance,flame retardancy,and insulation properties.Each phosphorous site on the polyphosphazene main chain can be connected to two identical or different side groups,and the chemical structure of different substituted side groups can give it different physical and chemical properties to meet different application requirements.In order to give full play to the performance advantages of polyphosphazene materials,the paper synthesized and prepared different kinds of fluoroalkoxy polyphosphazenes(PFAP),and used them as the matrix,through formula optimization research or modification of other materials,prepared super Hydrophobic insulating composite material and high-durability hydrophobic flame-retardant modified nylon fabric:1.Preparation of double bond-containing fluoroalkoxy polyphosphazene(E-PFAP)that can be cured by ultraviolet light(UV)at room temperature and has excellent insulation,hydrophobic and flame-retardant properties,and the content of unsaturated double bonds is used as 10%E-PFAP-10%is used as the matrix.It is compounded with multi-dimensional and multi-scale hydrophobic insulating functional fillers such as fluorinated h-BN,micron SiO₂ and nano SiO₂ to prepare E-PFAP-based insulators.Body-type insulating super-hydrophobic composite material.The paper explored the influence of factors such as the amount and orientation of h-BN,the amount and particle size of SiO₂ on the water contact angle,volume resistivity,breakdown voltage and surface flashover voltage of the composite material.Through the adjustment and optimization of the filler system,an E-PFAP-based composite material with a static contact angle of 151° and a rolling angle as low as 7° is obtained.At the same time,the material also exhibits good resistance to mechanical abrasion and ultraviolet radiation.While realizing super-hydrophobicity on the surface,the volume resistivity,breakdown voltage and flashover voltage of the composite material can reach 1.6×10¹³?·m,34.67kV/mm and 14kV,respectively,and have a limit oxygen of up to 53.8%.Index,UL-94 level reached V-0.2.The E-PFAP-10%with 10%unsaturated double bond content was selected for surface treatment of nylon fabric,and E-PFAP was successfully coated on the surface of nylon fabric by one-step immersion and UV light initiation and its curing was achieved.The modified nylon fabric sample showed the best flame retardant performance when the glue amount was 13.7 wt%,and its oxygen index LOI increased to 22.3%.At the same time,the introduction of E-PFAP-10%reduced the nylon fabric HRR and THR and other experimental results.When the sizing amount of nylon fabric is 7.4wt%,the hydrophobicity of its surface is maximized,and the contact angle is 143.5°.After 100 intense washing tests,the flame-retardant properties of the modified nylon fabric have been maintained.At the same time,the weight loss of the modified nylon fabric after washing is within 5%,showing excellent high durability.