Synthesis And Characterization Of Intumescent Flame Re Tardant And The Research Of Its Flame Retardant Performance In PC

Polycarbonate(PC) as one of the five general plastics, has excellent comprehensive performance, which widely used in the national economy in various fields. But the PC belong to flammable materials, which greatly limits its application. So the PC flame retardant modification is very important. Traditional containing halogen flame retardant with its adding quantity is little, and the advantages of good flame retardant effect, occupies an important position in the flame retardant PC, but it produces a large amount of poisonous, corrosive halolide gases, and release a lot of smoke when burnt. Along with the people environmental protection consciousness enhancement, halogen free flame retardant has gradually become the mainstream. In many halogen- free flame retardants, intumescent flame retardant agent in the flame retardant efficiency is relatively high, the advantages of low toxicity, low smoke, have become the focus in the flame retardant PC. The main research contents and results are listed as foiiowing:(1) Two novel triazine-based intumescent flame retardant namely TSN(2-(4’-sodium sulfonate) phenylammino-4, 6-di(2’-hydroxy) ethylamino-1, 3, 5-triafine) and TSNP(2-(4’-sodium sulfonate) phenylammino-4,6-bis(bis(2-(diphenoxyphosphoryl)oxy)) ethylamino-1,3,5-tria- fine) were designed an synthesized by using cyanogen chloride(TCT), diethanolamine and so on. The structure and thermal stability of TSN and TSNP were characterized by fo urier transform infrared spectrometry(FT-IR), nuclear magnetic resonance spectrometry(NMR) and mass spectra(MS) and themogravimetric ananlysis(TGA). The results show that TSN has good thermal stability, TSNP has better charring- form in air and nitrogen.(2) The flammability and thermal degradation properties of composites material were characterized by limiting oxygen index(LOI)、UL-94 measurements、Cone calorimeter test(CONE) and thermogravimetry ananlysis(TGA). The srsults showed that composite system can effectively improve the LOI value of the PC. The LOI value were 36.5% and 38.0%, respectively, when the adding amount 0.05 wt. % of TSN, 0.75 wt. % of TSNP. Thermal stability study shows that TSN improves the thermal stability of PC base material under high temperature and carbon rate; TSNP reduces the initial decomposition temperature of the PC, promoted the PC form dense carbo n layer. The Cone Calorimetry test(CONE) results showed that the pk-HRR of composite systems was reduced by 16.93%, 41.33% and the TTI increased by 46.74% and 50.00%, respectively, when compared with PC. The Fourier transformed infrared spectra(FT-IR) and Raman spectra revealed that the flame retardant mechanism of composite systems might be the condenced phase rather than in the gas phase. It was ascribed to its “aromatic” and phosphpric char formed during combusition. Super depth of field 3-D microscope system observation further indicated that flame retardant could promote forming stable and compact intumescent char layer and effectively protect the underlying PC form burning.