壳聚糖基含DOPO阻燃剂的制备及其在环氧树脂中的应用

Preparation of chitosan-based flame retardant with DOPO and EP application

通过壳聚糖、香草醛和9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)反应制备一种壳聚糖基含DOPO阻燃剂CS-L。采用红外光谱、紫外-可见光谱、X射线光电子能谱和热失重表征CS-L结构,并通过垂直燃烧、锥形量热和动态热机械分析研究CS-L对环氧树脂阻燃性能和玻璃化转变温度(T_(g))的影响。结果表明:制备的CS-L为预期结构。CS-L能抑制环氧树脂的滴落、燃烧以及烟的产生,由于其在气相和凝聚相中发挥阻燃作用。在燃烧过程中,15%CS-L使环氧树脂的热释放速率峰值、平均热释放速率、总热释放、平均质量损失率、总烟释放、总烟产量、平均比消光面积分别降低了243.2kW/m^(2)、58.8kW/m^(2)、18.4MJ/m^(2)、0.022g/s、698m^(2)/m^(2)、6.17m^(2)、120.6m^(2)/kg,使其残留量提高8.76%。CS-L对环氧树脂的T_(g)影响较小,含20%CS-L环氧树脂的T_(g)高达157.0℃。

A chitosan-based flame retardant with DOPO,named as CS-L,was prepared from chitosan,vanillin and DOPO(9,10-dihydro-9-oxa-10-phosphaphenantrtene-10-oxide).Its structure was characterized by FT-IR,UV-Vis,XPS and thermogravimetry.The effect of CS-L on the flame retardant property and glass transition temperature(T_(g)) of epoxy resin was studied.The results showed that the prepared CS-L had the expected structure.CS-L was able to inhibit dripping,burning and smoke generation of epoxy resin(EP)because it played the flame-retardant role in gas phase and condensed phase.The loading of 15wt%CS-L made the peak heat release rate,mean heat release rate,total heat release,mean mass loss rate,total smoke release,total smoke production and mean specific extinction area of EP reduced by 243.2kW/m^(2),58.8kW/m^(2),18.4MJ/m^(2),0.022g/s,698m^(2)/m^(2),6.17m^(2),120.6m^(2)/kg,respectively,and increased its residual amount by 8.76wt%.CS-L had little effect on the T_(g)of EP,and the T_(g) of EP with 20wt%CS-L was up to 157.0℃.