Study on Synthesis of Cyclotriphosphazene containing Aminopropyisilicone Functional Group as Flame Retardant

摘要

A novel non-halogen flame retardant APESP, cyclotriphosphazene containing six aminopropyliriethoxysilicone functional groups N_3P_3[NH(CH_2)_3Si(OCH_2CH_3)_3]_6, was synthesized by menas of S_N2 nucleophilic substitution reaction, using hexachlorocyclotriphosphazcnc(HCCP) and 3-aminopropyltriethoxy-silane (KH550) as material. Firstly the industrial grade HCCP was purified through recrystallization and sublimation. Then (he reaction process was investigated to prompt the yield, and the optimum reaction conditions were as follows: trieythylamine as acid-binding agent, teirahydrofuran as solvent, HCCP/KH55O/tricthylaminc molar ratio 1:7.2:7.2, dripping time: 1 hour, temperature: 67°C and reaction time: 20h. Maximum APESP yield reached 94.3%. The chemical structure and purity was characterized by element analysis, Fourier-transformed infrared spectroscopy (FTIR), mass spectrum, gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) analysis. The results showed that the structure of synthesized product is consistent with the theoretical structure, in which the chlorine atoms were completely substituted. The charge distribution calculation of HCCP and KH550 confirmed the reaction mechanism.