A liquid bi-functional phosphaphenanthrene siloxane molecule that imparts excellent flame-retardancy and improved mechanical properties to an epoxy amine network was identified and synthesized. The modifier was added to a reactive epoxy amine system to create a low viscosity, miscible, flame retardant resin potentially able to be manufactured via high-pressure resin transfer molding (HP-RTM). The additive reduced the viscosity of the epoxy resin system, remained miscible in the epoxy resin after cure producing a transparent network while simultaneously enhancing self-extinguishing flame retardancy, flexural properties and fracture toughness. At a concentration of 25%, the viscosity of the modified resin system prior to cure was very low (less than 100 mPa.s at 80 °C), cured rapidly (less than 8 min at 150 °C), exhibited a T_g over 110 °C, displayed improved flexural strength (13%), modulus (23%) and fracture toughness (23%), increased thermal stability and displayed self-extinguishing behaviour (UL 94 V-0). Examination after combustion revealed a transformation to a porous but stable char layer likely a result of the synergistic effects of the silicon and phosphorus. The results presented here using represent a promising development for next generation modified epoxy resin systems targeted towards rapid manufacturing of composite materials using HP-RTM.

鉴定并合成了具有优异阻燃性和改善了环氧胺网络机械性能的液体双功能磷杂菲硅氧烷分子。将该改性剂添加到反应性环氧胺体系中，以创建低粘度，易溶混的阻燃树脂，该树脂有可能可以通过高压树脂传递模塑（HP-RTM）进行生产。该添加剂降低了环氧树脂体系的粘度，固化后仍可混溶在环氧树脂中，形成透明网络，同时增强了自熄性的阻燃性，弯曲性能和断裂韧性。在浓度为25％时，固化之前的改性树脂体系的粘度非常低（在80°C时小于100 mPa.s），快速固化（在150°C时小于8分钟），表现出T_g在110°C时显示出改善的弯曲强度（13％），模量（23％）和断裂韧性（23％），更高的热稳定性并表现出自熄性（UL 94 V-0）。燃烧后的检查表明，可能转变为多孔但稳定的炭层，这可能是硅和磷的协同作用的结果。本文使用的结果代表了下一代改性环氧树脂系统的有希望的发展，该系统旨在使用HP-RTM快速制造复合材料。