Halogen-free Double-phosphonate Flame Retardants Synthesis And Application Of Research

Recently, fire hazards associated with the use of polymer materials, which cause the loss of life and property, are of particular concern among govenment regulatory bodies, consumers and manufacturers. The use of flame retardants to reduce combustibility of the polymers, and smoke or toxic fume production, therefore, the flame retardant is developing toward halogen-free, low toxicity and light smoke in the future.Halogen-free bis-phosphonate flame retardant is just about accord with this development demand. In this paper, halogen-free bis-phosphonate flame retardant such as 1,2-ethylene bis(dimethyl Phosphonate),1,2-ethylene bis(diethyl Phosphonate),methane bis(dimethyl Phosphonate) and methane bis(diethyl Phosphonate) were synthesized by the reaction Arbuzov. The effects of the catalyst, the reaction temperature, the reaction time, the reaction molecular ratio and the mass of the catalyst on the reaction yield were studied by orthogonal experiment. The optimal reaction conditions of 1,2-ethylene bis(dimethyl Phosphonate) were obtained:the reaction temperature 160℃, the reaction time 4.0h,the ratio of trimethyl phosphite tol,2-dibromoethane 3.0:1.0, the mass of the catalyst 0.5% of reactant. The optimal reaction conditions of 1,2-ethylene bis(diethyl Phosphonate) were obtained:the reaction temperature 165℃, the reaction time 6.0h,the ratio of triethyl phosphite to1,2-dibromoethane 3.0:1.0, the mass of the catalyst 0.5% of reactant. The optimal reaction conditions of methane bis(dimethyl Phosphonate) were obtained:the reaction temperature 150℃, the reaction time 10.0h,the ratio of trimethyl phosphite to dibromomethane 3.0:1.0, the mass of the catalyst 0.5% of reactant. The optimal reaction conditions of methane bis(diethyl Phosphonate) were obtained:the reaction temperature 155℃, the reaction time 14.0h,the ratio of triethyl phosphite to dibromomethane 3.0:1.0, the mass of the catalyst 0.5% of reactant. ESI-MS,IR and 1HNMR were used to characterize its chemical structure. The thermal degradation behavior of flame retardants and flame retarded polymer materials was investigated by TGA.1,2-ethylene bis(dimethyl Phosphonate) contributes an excellent flame retardaney to polyurethane soft foam products. V-0 ratings in the UL-94 vertical test were aehieved at 13% loading of 1,2-ethylene bis(dimethyl Phosphonate), when LOI values reached at least27.2%. The physical properties of polyurethane soft foam products treated by fire-retardant was significantly enhanced, and showed good performance of flame retardant and plasticity.