新型高效含磷杂吖嗪基阻燃剂的构建及其阻燃环氧树脂性能与机理研究

Epoxy resin is widely used in modern industrial area. However, the high loading of flame retardants and decrease in heat resistance, mechanical and other properties are the bottleneck problems during its flame retarded modification. In this project, the low loading and high flame-retardant efficiency of phenophosphazine unit will be as the skeleton of flame retardants, and the reactive activity of P-H bond in the 5, 10-dihydro-phenophosphazine-10-oxide (DPPA)molecule with a variety of functional groups will be used to design molecular structures of curing agent, epoxy pre-polymer and comonomer. So the novel phenophosphazine-containing reactive flame retardants with high-efficient flame retardancy can be builded by introduction of groups that can improve flame retardancy, heat resistance and other properties of materials via simple and environment-friendly synthetic method. The structure of flame retardant will be regulated and the processing technology of epoxy resins will be optimized to make flame retardant give epoxy resins excellent flame retardancy at low loading and at the same time impove its heat resistance, machanical and other properties. Systemic investigation in the influence of diversity structures of flame retardants on the epoxy resins' curing process, and flame retarded, heat resistant, and flame retarded mechanism will be conducted to figure out the relationship between structure and performances and flame retarded mechanism. The final aim is to clarify the theoretical design-frame and applied technology of intrinsic halogen-free flame retarded epoxy resin materials containing phenophosphazine unit and to provide new pathway of high-effective halogen-free flame retardant system for organic polymer materials.

现代工业领域中广泛使用的环氧树脂材料，阻燃改性时存在阻燃剂用量大，以及在提高阻燃性能的同时造成材料耐热等性能下降的瓶颈问题。本项目拟采用具有用量低且阻燃效率高的磷杂吖嗪基为骨架，利用5,10-二氢-磷杂吖嗪-10-氧化物 (DPPA)分子中P-H键能够与多种官能团反应的特性，设计固化剂、环氧预聚物和共聚单体的分子结构，采用简洁和环境友好的合成方法，引入能够改善材料阻燃、耐热等性能的基团，构建新型高效含磷杂吖嗪基反应型阻燃剂。通过调控阻燃剂的分子结构和优化环氧树脂的加工工艺，使阻燃剂能以较小的用量赋予环氧树脂优异阻燃性能，同时改善材料耐热等性能，并系统地研究阻燃剂的结构多样性对固化过程和固化物阻燃、耐热以及阻燃机理的影响，揭示阻燃剂结构对阻燃树脂性能以及阻燃机理的影响规律，阐明含磷杂吖嗪基本征型无卤阻燃环氧树脂材料的设计理论框架和应用工艺，为有机高分子材料的高效无卤阻燃提供新途径。

现代工业领域中广泛使用的环氧树脂材料，阻燃改性时存在阻燃剂用量大，以及在提高阻燃性能的同时造成材料耐热等性能下降的问题。本项目拟采用具有用量低且阻燃效率高的磷杂吖嗪基为骨架，利用5,10-二氢-磷杂吖嗪-10-氧化物(DPPA)分子中P-H键的反应特性，设计阻燃剂的分子结构，引入能够改善材料阻燃、耐热等性能的基团，构建新型高效含磷杂吖嗪基反应型阻燃剂。通过调控阻燃剂的分子结构和优化树脂的加工工艺，使阻燃剂能以较小的用量赋予环氧树脂优异阻燃性能，同时改善材料其它性能。.合成出四种新型高效含磷杂吖嗪基反应型阻燃剂，分别记为阻燃剂1、2、3和4，表征了其结构。这四种阻燃剂均能以较小的用量赋予环氧树脂优异的阻燃性能，同时对树脂其它性能产生较小的负面影响，或者提高树脂某些性能。阻燃剂1以3 wt%添加量使环氧树脂的阻燃级别达到UL-94 V-0级，极限氧指数（LOI）由24.1%升高至31.8%，同时使其拉伸强度由75.1 MPa升高至85.9 MPa，冲击强度维持不变，对其初始热分解温度（T5%，氮气氛围）和玻璃化转变温度（Tg）仅有微小的负面影响。阻燃剂2以1.5 wt%添加量使环氧树脂的阻燃级别达到UL-94 V-0级，LOI值提高至29.5%，同时使其弯曲强度由114.8 MPa升高至123.3 MPa，Tg维持不变，T5%的下降幅度仅为1.97%，拉伸强度仅稍有降低。阻燃剂3以2.0 wt%添加量使环氧树脂的阻燃级别达到UL-94 V-0级，同时使其Tg由160.0 ℃升高至169.6 ℃，T5%由352.3 ℃升高至359.6 ℃。阻燃剂4以2.5 wt%添加量使环氧树脂的阻燃级别达到UL-94 V-0级，同时使其Tg由161.6 ℃升高至169.0 ℃，T5%由358.7 ℃升高至360.2 ℃。这四种阻燃剂均在气相和凝聚相中发挥阻燃作用。该研究为环氧树脂的无卤高效阻燃提供新途径。目前以此内容以第一作者发表3篇SCI收录论文，申请两项专利。.项目期间对其它类型阻燃剂进行了研究，包括含磷氮反应型阻燃剂、DPPA与改性纳米二氧化钛的复配阻燃剂，有机阻燃剂改性的镁铝双氢氧化物。该研究有助于对各种阻燃剂进行了解，扩展研究思路。以该内容以第一作者发表3篇CSCD收录论文，申请一项专利。.该项目的执行情况和研究目标的完成情况均良好。