College of Environment and Resources, Fuzhou University, 2 Xueyuan Road, Fuzhou 350116, PR China.
State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, PR China; Institute of Textiles & Clothing, The Hong Kong Polytechnic University, Hunghom, Hong Kong, China.
J Colloid Interface Sci. 2018 Jul 1;521:160-171. doi: 10.1016/j.jcis.2018.02.054. Epub 2018 Feb 19.
A facile approach was developed to simultaneously functionalize and reduce graphene oxide (GO) with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-phosphonamidate. To achieve stable dispersion and effective stress transfer, graphene was functionalized by polyethyleneimine (PEI). To improve the fire resistance of bare graphene, DOPO was grafted on the surface of PEI-reduced graphene oxide (PEI-rGO) to obtain the grafting of DOPO-phosphonamidate on the graphene. A morphological study indicated that, due to the good interfacial interaction between the functionalized graphene and epoxy (EP), functionalized reduced graphene oxide (f-rGO) was well-dispersed in the host polymer. Incorporation of 3.0 wt% f-rGO led to the increased char yields of the EP. Moreover, the storage modulus and glass transition temperature were improved, respectively. The evaluation of combustion behavior demonstrated that the peak heat release rate and total heat release of f-rGO/EP were reduced by 31% and 34.3%, respectively, compared to those of neat EP. This dramatically reduced fire hazards were mainly attributed to the synergistic effect of f-RGO. On one hand, DOPO-phosphonamidate on the surface of GO promoted flame inhibition in the gas phase while protecting the rGO against fire. On the other hand, the adsorption and barrier effect of rGO inhibited the heat and gas release, respectively, promoting the formation of graphitized carbons.
开发了一种简便的方法，用 9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物（DOPO）-膦酸酰胺酯同时对氧化石墨烯（GO）进行功能化和还原。为了实现稳定的分散和有效的应力传递，使用聚乙烯亚胺（PEI）对石墨烯进行功能化。为了提高裸露石墨烯的阻燃性，将 DOPO 接枝到 PEI-还原氧化石墨烯（PEI-rGO）的表面上，从而在石墨烯上接枝 DOPO-膦酸酰胺酯。形态研究表明，由于功能化石墨烯和环氧树脂（EP）之间的良好界面相互作用，功能化还原氧化石墨烯（f-rGO）在主体聚合物中得到了很好的分散。加入 3.0wt%的 f-rGO 导致 EP 的残炭产率增加。此外，存储模量和玻璃化转变温度分别得到提高。燃烧行为评估表明，与纯 EP 相比，f-rGO/EP 的峰值放热率和总放热量分别降低了 31%和 34.3%。这种显著降低的火灾危险主要归因于 f-RGO 的协同效应。一方面，GO 表面上的 DOPO-膦酸酰胺酯在气相中促进了火焰抑制，同时保护 rGO 免受火灾。另一方面，rGO 的吸附和阻挡效应分别抑制了热和气体的释放，促进了石墨化碳的形成。
