According to the requirement of the foreign clients, our company began to develop high degree of polymerization Ammonium polyphosphate. At present, we have managed to develop APP with high degree of polymerization that reaches several hundred. The product is an effective and nonpoisonous inflaming retarding agent. Due to its high content of N and P, the product has some merits, such as the high temperature of decomposition, good heat stability, small moisture absorption, small water solubility, small specific gravity and good dispersivity and so on. Furthermore, the product is nearly neutral and won't react when mixed with any other product. So it is applied very fast abroad in the nearly 20 years. It also can be an additive inflaming retarding agent widely applied in lumber, paper, coating, plastics and rubber products, or used together with other inflaming retarding agents.The function of APP with high degree of polymerization of our factory has achieved the international level of the same kind of products. However, our price is far lower than theirs. Our products have been exported to Germany, Taiwan and so on.