Synthesis Of Novel Nitrogen Phosphorus Containing Flame Retardants And Its Application On Polypropylene

In this paper,two kinds of new triazine-based flame retardants(DCPA and MBEL)have beenreported,synthesized from 1,3-Diphenylguanidine,cyanuric acid,2-Mercaptobenzothiazole andMelamine.And the results of Fourier transform infrared spectroscopy(FTIR),1H-NMR,andelemental analysis(EA)indicated that these two target products own the expected chemicalcomposition and molecule structure.Thermogravimetric analysis(TGA)was employed todetermine the thermal stability of these two products.The initial decomposition temperature ofDCPA was 246.8? in nitrogen atmosphere,the maximum decomposition rate was 17.39%/min;decomposition temperature of MBEL at loss 5wt% was 220.1?,two peak decompositiontemperatures were 265.8? and 305.9?,the decomposition rate were 13.20%/min,10.43%/minrespectively.The initial decomposition temperatures are higher than processing temperatures ofmany polymers and lower than decomposition temperatures of those polymers,so flameretardants can be decomposed before the polymer matrix and then play a good role.Polyolefin is a kind of environmentally friendly material in its entire product lifecycle including of production,processing,application and abandonment.Because of its cost-effective,it is widely used in the fields of automobile,construction,electronics and so on.Among them,polypropylene and polyethylene are two main varieties of polyolef ins,which occupy a large proportion in general plastics.The DPCA and MBEL were compounded with other flame retardants and applied to the flame retardant PP respectively.The flame retardancy and mechanical properties were studied by means of Limit oxygen index(LOI),vertical burning(UL-94),tensile test and impact test.The results indicated that the FR-PP of DCPA could achieve about 23% in LOI test,V-2 grade in UL 94 test;After adding MBEL compound flame retardant system to PP,the LOI of FR-PP increased to more than 23%,although the combustion time was shorter in the combustion test,but melt dripping phenomenon makes them only reach UL94 V-2.The tensile strength and impact strength of polymer decreased slightly while the elongation at break decreased obviously.Tris(hydroxymethyl)phosphine oxide glycidyl ether was synthesized by epichlorohydrin and Tris(hydroxymethyl)phosphine oxide.THPO and THPE were characterized by FTIR,EA and NMR.The results indicated that target products own the expected chemical composition and molecule structure.The thermal properties of THPE were analyzed by thermogravimetry(TGA).The initial decomposition temperature of THPE was 288.4 ? in nitrogen atmosphere,its decomposition temperature is very high.The mass residue at 650? is 42.01%.The residual carbon content is high,which can effectively play the role of flame retardant in the condensed phase.