Shanghai Juqian Chemical Co., Ltd.

The phosphorus content of ammonium polyphosphate as high as 30% ~ 32%, 14% ~ 16% nitrogen. This kind of flame retardant is the most prominent feature of the generation of smoke during combustion is extremely low, does not produce hydrogen halide. The ammonium polyphosphate has good thermal stability, can substitute for ammonium phosphate.

Ammonium polyphosphate is a white crystalline or amorphous powder. APP water solubility and hygroscopicity increases with the polymer. According to the different degree of polymerization of N in China can be divided into water soluble (n=10 ~ 20, the relative molecular mass of 2000 ~ 1000) and water insoluble (n>20, relative molecular mass greater than 2000) two kinds. N can be greater than 1000. N<100 is called crystalline phase I (APP I) in foreign countries, and n>1000 is called crystalline phase APP (APP II). N<100 short chain APP to water sensitivity (hydrolysis) than the long chain (M>1000) APP large, and the latter's thermal stability and resistance to hydrolysis. Long chain APP began to decompose into phosphoric acid and ammonia in the above 300 degrees, while the short chain APP at 150 DEG to start breaking down.

The crystalline APP is used as a water insoluble long-chain polyphosphate ammonium salt. APP P, high nitrogen content, the synergistic effect of phosphorus and nitrogen system flame retardant. The relatively low density, good dispersion, good chemical stability, low toxicity and smoke.