磷酸乙基新戊二醇酯的合成及阻燃性能测试

Synthesis and Flame Retardant Performance of Ethyl Neopentyl Phosphate

以新戊二醇、三氯氧磷、乙醇为原料,合成了一种阻燃剂磷酸乙基新戊二醇酯(Ⅱ),采用FTIR、1HNMR、13CNMR、31PNMR、ESI-MS表征了其化学结构。考察了物质的量比〔n(新戊二醇磷酰氯)∶n(乙醇)〕、反应温度和反应时间等因素对反应的影响,得到最佳反应条件为∶n(新戊二醇磷酰氯)∶n(乙醇)=1∶5,反应温度50℃,反应时间8 h,产率达80.8%。将合成的阻燃剂磷酸乙基新戊二醇酯添加到硬质聚氨酯泡沫(RPUF)中,通过极限氧指数(LOI)、垂直燃烧(UL-94)实验测定了RPUF的阻燃性能,以及利用TGA表征了阻燃剂和RPUF的热稳定性。结果表明:磷酸乙基新戊二醇酯的添加,在一定程度上降低了RPUF的热稳定性,但是RPUF的阻燃性能有所提高。添加量为30%(质量分数,以材料总质量计)时可使RPUF的LOI值从17.1%提高到22.5%,通过垂直燃烧V-2级,以及在800℃时,残炭量由15.8%增加到18.9%。

A kind of flame retardant,2-ethoxy-5,5-dimethyl-[1,3,2]dioxaphosphinane(Ⅱ)was synthesized using neopentylglycol,phosphorus oxychloride and ethanol as raw materials.Its chemical structure was identified by means of FTIR,1HNMR,13CNMR,31PNMR and ESI-MS.The effects of molar ratio of2-chloro-5,5-dimethyl-[1,3,2]dioxaphosphinane to ethanol,reaction time and reaction temperature on the yield of the target product were studied.The results showed that the optimum conditions were obtained as follows:n(2-chloro-5,5-dimethyl-[1,3,2]dioxaphosphinane)∶n(ethanol)=1∶5,reaction temperature 50℃,reaction time 8 h.Under these conditions,the yield of the target product reached 80.8%.Subsequently,the synthesized flame retardant was then added to rigid polyurethane foams(RPUF).The flame retardancy of the resulting composite material was tested by limiting oxygen index(LOI)and vertical(UL-94)tests.Meanwhile,the thermal stability of flame retardant and RPUF was characterized by thermogravimetric analysis(TGA).The results indicated that the addition of 2-ethoxy-5,5-dimethyl-[1,3,2]dioxaphosphinane reduced the thermal stability of RPUF to a certain extent,but improved its flame retardancy.The composite containing 30%compoundⅡachieved UL-94 V-2 rating with a LOI value of 22.5%,higher than that of pure RPUF(17.1%),and the residual mass increased from 15.8%(for pure RPUF)to 18.9%.