In situ preparation of reduced graphene oxide/DOPO-based phosphonamidate hybrids towards high-performance epoxy nanocomposites
In situ preparation of reduced graphene oxide/DOPO-based phosphonamidate hybrids towards high-performance epoxy nanocomposites
复制标题
原位制备还原氧化石墨烯/DOPO基膦酰胺杂化物以制备高性能环氧纳米复合材料
DOI：
10.1016/j.compositesb.2017.05.024
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发表时间：
2017-08-15
影响因子：
13.1
通讯作者：
Hu, Yuan
中科院分区：
文献类型：
--
作者：
Guo, Wenwen;Yu, Bin;Hu, Yuan
该工作报告了一种基于哌嗪还原的氧化石墨烯（rGO）/哌嗪基DOPO-膦酰胺化物（PiP-DOPO）的策略，以克服石墨烯的分散和环氧树脂（EP）基质与添加剂型阻燃剂的机械劣化的挑战。将氧化石墨烯（GO）功能化，同时用哌嗪还原，然后通过原位反应将GO引入到PiP-DOPO中，形成杂化物（PD-rGo）。随后，将PD-rGO掺入环氧树脂（EP）中以制备纳米复合材料。对PD-rGO的结构和热性能进行了表征。EP中PD-rGO的存在改善了700 ℃下的炭产率，并降低了氮气下的最大质量损失速率，表明在高温下改善了热稳定性。燃烧性能的评价表明，与纯EP相比，通过在EP中添加4重量%的PD-rG 010（在混合物中为10重量%的rGO），PHRR和THR值分别显著降低43.0%和30.2%。具有4 wt% PD-rG 05（在混杂物中5wt%rGO）的环氧复合物可以通过UL-94 VO等级，LOI为28.0%。其阻燃机理可归因于PD-rGO杂化材料中两种成分之间的协同作用：在UL-94燃烧测试中，PiP-DOPO有利于抑制火焰蔓延，而石墨烯的阻挡效应在抑制热释放速率方面占主导地位。此外，由于杂化物中石墨烯的高刚度，PD-rGO杂化物的添加导致储能模量和拉伸强度略微改善。PD-rGO杂化材料结合了石墨烯优异的力学性能和DOPO基化合物良好的阻燃效果，为同时改善阻燃性能和力学性能的高性能环氧树脂纳米复合材料提供了一种很有前途的解决方案。(C)2017爱思唯尔有限公司版权所有
The work reports a strategy based on piperazine-reduced graphene oxide (rGO)/piperazine-based DOPO-phosphonamidate (PiP-DOPO) to overcome the challenge of the dispersion of graphene and mechanical deterioration of epoxy resin (EP) matrix with additive-type flame retardants. Graphene oxide (GO) was functionalized and reduced by piperazine simultaneously, and then incorporated into PiP-DOPO through in situ reaction, resulting in the formation of the hybrids (PD-rGo). Subsequently, the PD-rGO was incorporated into epoxy resin (EP) to fabricate nanocomposite. The structure and thermal properties of PD-rGO were well characterized. The presence of PD-rGO in EP improved the char yields at 700 degrees C and reduced the maximum mass loss rate under nitrogen, indicating the improved thermal stability at elevated temperature. The evaluation of combustion behavior demonstrated that the PHRR and THR values were decreased significantly by 43.0% and 30.2% by the addition of 4 wt% PD-rG010 (10 wt% rGO in hybrid) in EP respectively, in comparison to neat EP. The epoxy composite with 4 wt% PD-rG05 (5 wt% rGO in hybrid) could pass UL-94 VO rating and the LOI was 28.0%. The flame retardant mechanism could be attributed to the synergism between two compositions in PD-rGO hybrid: the PiP-DOPO was favorable to flame spread inhibition in UL-94 burning test, while the barrier effect of graphene was dominant in terms of heat release rate suppression. Moreover, the addition of PD-rGO hybrid led to slightly improved storage modulus and tensile strength, due to the high stiffness of graphene in hybrids. The PD-rGO hybrid combines the outstanding mechanical behavior of graphene with the good flame retardant effect of DOPO-based compounds, which provides a promising solution to high performance epoxy nanocomposites with improved flame retardant and mechanical properties simultaneously. (C) 2017 Elsevier Ltd. All rights reserved.