Preparation Of The High Degree Of Polymerization Ammonium Polyphosphate (app)

As the development of the society, the high polymer material are more and more applied to people lives every aspect, but the mostly high polymer material are combustible material, greatly increased the latent fire risk. To reduce the fire risk, it required change the essential of this kind material. Although the traditional halogen flame retardant is very good to resistance burns, it release virulent and the corrosive gas. thus develops anti-does not have the halogen to burn the technology have a good future.Ammonium polyphosphate(APP) is a good flame retardant(FR), but the compatibility between APP and resin depends on the degree of polymerization. The study deeply investigated the synthetic technology and technology conditions that used NH₄H₂PO₄ and C0(NH₂)₂ as material. Deeply discussed the reaction time, temperature of reaction, reagent proportioning, initiating agent, explored the pressure of NH₃ and N₂, the flow rate of ammonia and nitrogen gases. Got optimum seeking technology and improved the quality of APP.The optimum technology conditions can be gained in the range of experiment: the high temperature T=295℃, reaction time t=100min, reagent proportioning: NH₄H₂P0₄:CO(NH₂)₂: A=1:1. 1:0.04, total pressure was 1.0atm, the pressure of NH₃ of rise step was 0.6atm, the pressure of N₂ of rise step was 0.4atm, the pressure of NH₃ of high temperature was 0.3atm, the pressure of N₂ of high temperature was 0.7atm. Got APP with 800 average degree of polymerization, and broke through the limitation that documents had reported on using NH₄H₂P0₄ and urea.The optimum technology conditions which have had gave were also could be industrialization. We have got APP with 700 average degree of polymerization.