Abstract Construction of carbon fiber (CF)-reinforced epoxy resin (EP) composites with excellent mechanical properties and desired flame retardancy is of particular interests for both academia and industry. In this work, an interfacial treatment strategy is used to address the above issues instead of adding flame retardants into the composites: without additional other flame retardants, EP is fire-retarded and reinforced only by surficially-treated CFs, which are fabricated by quickly soaking CFs in aqueous solution of polyelectrolyte complexes (PEC) consisting of polyethyleneimine (PEI) and ammonium polyphosphate (APP) at room temperature. Both the content and the morphology of the resulting PEC coating are conveniently tuned by adjusting the coating conditions. Without any change in the molding process of the EP/CF composites compared with the conventional process, the phosphorus-containing PEC coating of CF surfaces endows the EP/CF composites with high fire retardancy, exhibiting a high limiting oxygen index of 43%, UL-94 V-0 rating, and a 47% reduction in the peak heat release rate (PHRR) from cone calorimetry tests. Moreover, the PEC coating greatly improved the interaction between CFs and EP matrix, and enhanced the mechanical properties and glass transition temperature of the composite. Therefore, this work presents an effective and facile strategy to develop fiber-reinforced composites with superior fire-retardant and mechanical properties for future massive production.

中文翻译：

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表面处理的碳纤维通过可调且简便的工艺增强和阻燃的环氧树脂复合材料

摘要 具有优异机械性能和所需阻燃性的碳纤维 (CF) 增强环氧树脂 (EP) 复合材料的构建是学术界和工业界特别感兴趣的。在这项工作中，界面处理策略用于解决上述问题，而不是在复合材料中添加阻燃剂：没有额外的其他阻燃剂，EP 仅通过表面处理的 CF 进行阻燃和增强，CFs 通过快速浸泡制造室温下由聚乙烯亚胺 (PEI) 和聚磷酸铵 (APP) 组成的聚电解质复合物 (PEC) 水溶液中的 CF。通过调整涂层条件可以方便地调整所得 PEC 涂层的含量和形态。与常规工艺相比，EP/CF复合材料的成型工艺没有任何变化，CF表面的含磷PEC涂层赋予EP/CF复合材料高阻燃性，表现出43%的高极限氧指数，UL -94 V-0 等级，锥形量热法测试的峰值热释放率 (PHRR) 降低了 47%。此外，PEC涂层大大改善了CFs与EP基体之间的相互作用，提高了复合材料的力学性能和玻璃化转变温度。因此，这项工作提出了一种有效且简便的策略来开发具有优异阻燃和机械性能的纤维增强复合材料，以供未来大规模生产。显示出 43% 的高极限氧指数、UL-94 V-0 等级以及锥形量热法测试的峰值热释放率 (PHRR) 降低 47%。此外，PEC涂层大大改善了CFs与EP基体之间的相互作用，提高了复合材料的力学性能和玻璃化转变温度。因此，这项工作提出了一种有效且简便的策略来开发具有优异阻燃和机械性能的纤维增强复合材料，以供未来大规模生产。显示出 43% 的高极限氧指数、UL-94 V-0 等级以及锥形量热法测试的峰值热释放率 (PHRR) 降低 47%。此外，PEC涂层大大改善了CFs与EP基体之间的相互作用，提高了复合材料的力学性能和玻璃化转变温度。因此，这项工作提出了一种有效且简便的策略来开发具有优异阻燃和机械性能的纤维增强复合材料，以供未来大规模生产。