Study On The Interfacial Bonding Performance Of High Performance Polyaramid Fiber And Rubber

Polyaramid fiber have excellent properties such as high strength,high modulus,high temperature resistance and creep resistance,etc.However,their surfaces are smooth and chemically inert and their interfacial bonding properties with rubber are poor,so they generally require pretreatment such as impregnation when applied to fiber/rubber composites.Three impregnation systems,pre-condensed resorcinol-formaldehyde–latex(RFL),hydroxyl acrylic resin-amino resin–latex(HAAL)and hydroxyl acrylic resin-amino resin-latex-carbon nanotubes(HAAL-CNT)were used to comparatively study the interfacial bonding properties and bonding mechanism of polyaramid fibers and rubber.(1)The optimal formulation of the pre-condensed RFL impregnation system was determined and after its impregnation treatment of polyaramid fiber,the H extraction force of the composites could reach 184.5 N,the peeling force could reach 14.6 N and the number of dynamic cycles could reach 19011,the impregnation system had good stability.New reactive groups were introduced on the fiber surface and the resin of the impregnated layer formed a double continuous phase structure with the latex,through which the stress transfer could be effectively improved by connecting the fiber and the rubber matrix.For the polyaramid/nylon blended fibers,the H extraction force was 220.3 N,the peeling force was 22.2 N and the dynamic cycle number was20,955 after treatment with the optimal pre-condensation RFL impregnation system.(2)The optimal formulation of HAAL impregnation system was determined and after its impregnation treatment of polyaramid fiber,the H extraction force of the composite was 156.8 N,the peeling force was 13.4 N and the number of dynamic cycles was 16,951,the impregnation system had good stability.New reactive groups were likewise introduced on the fiber surface and the resin of the impregnated layer formed an island structure with the latex,through which the transfer of stress could be improved to some extent by connecting the fiber and the rubber matrix.For the polyaramid/nylon blended fibers,the H extraction force is 194.5 N,the peeling force is16.7 N and the number of dynamic cycles is 19,502 after treatment with the optimal HAAL impregnation system.(3)The optimal HAAL-CNT impregnation system was determined and the interfacial bonding performance of the composites was significantly improved by its impregnation treatment of polyaramid fiber,with an H extraction force of 182.5 N,a peeling force of 13.8 N and the number of dynamic cycles was 19,435.CNT enhancement affects the stability of the impregnation system to some extent.CNT induces the resin to form smaller island phase structures and has a reinforcing effect on the impregnated layer,thus improving the stress transfer efficiency.For the polyaramid/nylon blended fibers,the H extraction force was 200.9 N,the peeling force was 18.9N and the number of dynamic cycles was 22,802 after treatment with the optimal HAAL-CNT impregnation system.By comparing the above three impregnation systems,the interfacial bonding performance of the polyaramid-fiber-rubber composite impregnated with carbon nanotube-reinforced HAAL system and the pre-condensed RFL system is comparable,and the HAAL impregnation system can replace the pre-condensed RFL impregnation system.