The Optimize Design Of The Properties Of Smoke Suppressant And Flame Retardant HDPE For Cable Protection Pipe

This paper introduced systematicly the research work of the smoke suppressant and flame retardant HDPE for cable protection pipe, including the halogen and halogen-free flame retardant system, and the intumescent flame retardant system. The combustion performance, mechanical performance, the heat-resisting performance, rheology properties, crystallization behavior etc. are studied, and the combustion mechanism is investigated by the means of TGA. It is emphasized to promote the tougheness of halogen-free flame retardant HDPE materials, and to develop a well overall performance material. The main conclusions are listed as follows:(1) The content of halogen flame retardant additives is smaller, and the overall performance of material is outstanding. This is because of the very good compatibility between the additives and HDPE matrix.(2) The toughness of MH/ZB halogen-free flame retardant HDPE greatly reduces along with the content of MH/ZB increases, simultaneously the processing ability of flame material is getting worse, due to the bad compatibility between MH particles and HDPE matrix.(3) Amino silicon oil can improve the impact strength at some degree, but it makes the tensile strength and modulus decrease a lot. At the same time, amino silicon oil cannot improve the flame retardant behavior of the system. The toughening mechanism of amino silicon oil is that it could soften the polyethylene resin around the flame retardant particles, thus forms a flexible interphase with acertain thickness between the flame retardant additives and the matrix.(4) The flame retardant additives' granularity and the distribution play a very important role to the final performance of material. The additives with a small particle size and centralized distribution can be dispersed in the matrix evenly, and can enhance the tensile toughness and impact toughness of material, also the flame retardant performance of material.(5) PE-g-MAH (polyethylene grafted with maleic anhydride) can modify the interface compatibility of the composites and improve the dispersing level of flame retardant additives in the matrix, and then improve material's toughness. The PE-g-MAH toughening mechanism mainly was "the interface acid and alkali match" and forming a flexible interphase layer.(6) The suitable and proportional intumescent flame retardant additives (the TPP/PER/MA system) may enhance the toughness of MH/ZB flame retardant HOPE material, but fails to enhance the combustion performance, simultaneously causes the thermostability of material to drop.(7) The TG analysis of MH/ZB halogen-free flame retardant HDPE indicates: in the combustion process, the dehydration and heat absorption reduced the thermal decomposition speed of material; in the final stage of combustion, MH/ZB can promote the neat production of coal quantity of the system, thus it can bring a good fire retardant effects.(8) The DSC measurement of MH/ZB halogen-free flame retardant HDPE shows: after the usage of MH/ZB, the heat-resisting of material has a little enhancement, the crystallization rate increases, the crystallinity changes a little.