Graphene oxide (GO) was prepared from graphite powder by the classic Hummers method, and modified by 1-N-butyl-3-methylimidazolium hexafluorophosphate (IL) and 3-aminopropyltriethoxysilane (KH550) to obtain ionic liquid functionalized graphene oxide (ILGO). ILGO, compounded with traditional flame retardants (ammonium polyphosphate and expandable graphite), was used in unsaturated polyester resin (UPR) to enhance the flame retardancy. The flame retardant property and thermal degradation of the UPR composites were analyzed by limiting oxygen index (LOI), UL-94, cone calorimeter test (CCT), and thermogravimetric analysis (TGA). The results show that there is an obvious synergism between ILGO and the traditional flame retardants. The LOI value of UPR-4 containing ILGO reaches 28.2% and passes V-0 of UL-94, and UPR-4's the initial temperature (T_i), maximum degradation temperature (T_max), and residual carbon greatly increase. The experimental data shows that ILGO can promote UPR to form more residual carbon during combustion, enhance thermal stability, and make the material not easy to decompose. The morphology of carbon layer measured after CCT was observed by scanning electron microscope (SEM). SEM images show that the surface of char layer of UPR-4 containing ILGO becomes smoother, flatter and denser, compared with UPR containing only flame retardants. The cohesiveness and compact structure residual carbon can effectively prevent the oxygen, combustible gas, and heat transfer between the flame zone and the base material to reduce flammability.

中文翻译：

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离子液体功能化氧化石墨烯在不饱和聚酯树脂中的阻燃性

氧化石墨烯（GO）采用经典的Hummers法以石墨粉为原料，经1-N-丁基-3-甲基咪唑六氟磷酸盐（IL）和3-氨基丙基三乙氧基硅烷（KH550）改性，得到离子液体功能化氧化石墨烯（ILGO）。ILGO与传统阻燃剂（聚磷酸铵和可膨胀石墨）复合，用于不饱和聚酯树脂（UPR）以增强阻燃性。通过极限氧指数（LOI）、UL-94、锥形量热仪测试（CCT）和热重分析（TGA）对UPR复合材料的阻燃性能和热降解性能进行了分析。结果表明，ILGO与传统阻燃剂具有明显的协同作用。含ILGO的UPR-4的LOI值达到28.2%，通过UL-94的V-0，UPR-4的初始温度（T _i )、最大降解温度 ( T _max )和残留碳大大增加。实验数据表明，ILGO可以促进UPR在燃烧过程中形成更多的残碳，增强热稳定性，使材料不易分解。通过扫描电子显微镜（SEM）观察CCT后测量的碳层形貌。SEM图像显示，与仅含阻燃剂的UPR相比，含ILGO的UPR-4炭层表面变得更光滑、更平整、更致密。内聚性和致密结构的残碳能有效阻止火焰区与基材之间的氧气、可燃气体和热传递，降低可燃性。