Study In Synthesis Of Novel Halogen-Free Flame Retardants

Polyethylene (PP) and Polypropylene (PP) are widely used thermoplastic materials. PE has many good characters, such as lightweight, no poisonous, good electrical insulation, chemical resistance and easy processibility. PP's density is very low only 0.90～0.91g/cm3. It has good surface brightness, high yield strength, good wear resistance and chemical durability. But these two materials are very easy combustible, so the flame retardancy of them is very important in widening their application areas. Intumescent flame retardants (IFR) have good flame retardancy in polyolefin. IFR's function is not only by simply charring but also developing an expanded char layer on the surface of the materials when they are exposed to fire. In this paper, three kinds of flame retardants were synthesized, A, B, and C. The first two are triazine derivatives, the third is bicyclophosphate. A is N,N-di(2,4-dihydroxyethylamino -1,3,5-s-triazino) ethylenediamine, B is poly-2-amino-4,6-dihydroxyethylamino-1 , 3 , 5-s-triazino , C is 1-oxo-4-hydroxym ethyl-2 , 6 ,7-trioxa-1-phosphabicyclo[2.2.2] octane. The effects of various reaction conditions such as solvent, reaction temperature, reaction time, and pH value were investigated. Blending A,B and APP,C in different proportion separately can come into Intumescent Fire Retardand. (IFR) .Adding these retardand into PP, testing oxygen index and the property vertical burning, and studying relation of flame retardancy and the amount of IFR, indicate that above IFR can increase oxygen index of PP, and has good flame retardancy.