“溴-碳分子协同阻燃体系”对溴系阻燃剂的抑烟作用及其机理研究

Brominated flame retardant is widely used in the flame retardation of polymer due to its banlanced mechanical properties, flame retardancy and processing advantages. However, polymer/brominated flame retardant system generated a great of heat and smoke during combustion. We designed the synergistic flame retardation of graphene and brominated styrenic-based polymer by the Friedel-Crafts alkylated reaction. On one hand, brominated styrenic-based polymer has the high performance of flame retardation by capturing the radicals forming in thermal degradation of polymer. On another hand, graphene can form the network structure during combustion, which has the potentiality of cutting off the exchange of heat and smoke. Therefore, the synergistic effect of graphene and brominated styrenic-based polymer may improve the defect of brominated styrenic-based polymer in generating much heat and smoke during combustion. It is helpful to comprehend the synergistic mechanism of graphene and brominated styrenic-based polymer by way of the research and discuss of the "closed effect" of network structure for radicals and the ability of capturing radicals in the "closed effect" for brominated flame retardant.

目前"无卤化"风潮席卷高分子阻燃材料领域，而现有无卤阻燃剂的综合阻燃效果远不如溴系阻燃剂，想要实现高分子材料的完全"无卤化"阻燃至少在今后很长一段时间是不可能的。本项目针对环保溴系阻燃剂高发热和高发烟的问题，采用Friedel-Crafts反应从分子结构上实现溴代苯乙烯聚合物类阻燃剂与石墨烯的协同复配，既保留了溴系阻燃剂的高效阻燃性，又利用石墨烯燃烧过程中形成的网络结构，将溴系阻燃剂捕获自由基的过程从气相转移到凝聚相，试图解决溴系阻燃剂在烟密度、热释放速率等方面的问题。并通过对"溴-碳分子协同阻燃体系"微观结构的可控构筑，初步总结燃烧过程中形成的网络结构对聚合物热降解产生自由基的"密闭"效果及溴系阻燃剂在网络结构内部捕获自由基的能力，揭示溴系阻燃剂与石墨烯分子结构上的协同阻燃规律，为实现溴系阻燃剂的"低热低烟化"，满足日益严格的阻燃剂生产和使用标准提供理论指导。

目前“无卤化”风潮席卷高分子阻燃材料领域，而现有无卤阻燃剂的综合阻燃效果远不如溴系阻燃剂，想要实现高分子材料的完全“无卤化”阻燃至少在今后很长一段时间是不可能的。本项目首先解决了石墨烯、碳纳米管、富勒烯等碳纳米材料在高分子基体中的分散问题，发现了Friedel-Crafts反应在高分子碳纳米复合材料中的作用机理，揭示了Friedel-Crafts反应可使碳纳米材料与高分子链段通过静电吸附作用相连接，为改善材料阻燃性能构筑完整连续的阻隔炭层打下基础。而且，针对环保溴系阻燃剂高发热和高发烟的问题，将引入Friedel-Crafts反应的碳纳米材料与溴系阻燃剂协同复配，既保留了溴系阻燃剂的高效阻燃性，又利用石墨烯燃烧过程中形成的连续网络结构，将溴系阻燃剂捕获自由基的过程从气相转移到凝聚相，解决了溴系阻燃剂在烟密度、热释放速率等方面的问题，总结出了燃烧过程中形成的网络结构对聚合物热降解产生自由基的“密闭”效果及溴系阻燃剂在网络结构内部捕获自由基的能力，揭示溴系阻燃剂与石墨烯分子结构上的协同阻燃规律，为实现溴系阻燃剂的“低热低烟化”，满足日益严格的阻燃剂生产和使用标准提供理论指导。