Study On High-performance Coating Materials For Carbon Fiber Woven Cloth

With the upgrading of aviation and aerospace vehicles,a large number of circuits and electronic equipments between the outer skin and the inner warehouse need to be protected by high-performance coating materials.However,at present,domestic and foreign commonly used coating materials in this field,such as polyester-based acrylate coated fabrics,PVC-based acrylate coated fabrics,cannot meet the increasing application requirements in the above fields.This study was intended to prepare high-performance acrylate modified silicone materials with low cost,excellent heat resistance,high water resistance and extremely strong adhesion for coated carbon fiber woven cloth.In this study,the best carbon fiber woven cloth silicone coating was selected from four representative silicone coatings.High-performance acrylate materials for the modification of silicone coatings were prepared by a bulk polymerization method using azobisisobutyronitrile(AIBN)as the initiator and using butyl acrylate(BA),styrene(St),methacrylic acid(MAA)and hexamethylene diisocyanate(HDI)as the polymerization monomers based on the free radical polymerization mechanism.Then polyvinyl alcohol(PVA)was selected as a solubilizing agent and an optimally formulated acrylate material was used to modify the optimum silicone coating material by physical blending method.In addition,the flexibility,water absorption,flame retardancy,adhesion,wettability and other properties of the coatings were tested.And the molecular structure of the coating,the solubilizing effect of PVA and the phase composition of the flame retardant were also studied by infrared spectroscopy,DSC,and XRD,respectively.The experimental results show that:(1)Two-component silicone material was the best choice for carbon fiber woven cloth coating among the four commercially available silicone coatings.(2)In the optimal acrylate material formulation,the AIBN content was 2.0 %,BA,St,MAA,HDI content were 46.0 %,46.0 %,5.0 %,3.0 %,respectively.With the increase of the HDI amount,the water absorption of the coating film decreases first and then increases.The FTIR spectra showed that the polymerization reaction between acrylate monomers was complete,and the addition of functional monomer HDI contributed to cross-linking between polymer chains.(3)DSC spectra showed that PVA not only improved the compatibility of acrylate coating and silicone coating,but also enhanced the heat resistance of the blends from 220 ? to 300 ?.The adhesion force and contact angle test results showed that silicone coating had excellent adhesion through the physical blending modification.The fluidity and infiltration of the modified coating were superior to those before the modification.Thus,the aim of modification could be achieved.Moreover,4148 flame retardant(20 % content)showed best flame retardant effect.