A flame retardant filler having brominated silica particles, for example, imparts flame retardancy to manufactured articles such as printed circuit boards (PCBs), connectors, and other articles of manufacture that employ thermosetting plastics or thermoplastics. In this example, brominated silica particles serve both as a filler for rheology control (viscosity, flow, etc.) and a flame retardant. In an exemplary application, a PCB laminate stack-up includes conductive planes separated from each other by a dielectric material that includes a flame retardant filler comprised of brominated silica particles. In an exemplary method of synthesizing the brominated silica particles, a monomer having a brominated aromatic functional group is reacted with functionalized silica particles (e.g., isocyanate, vinyl, amine, or epoxy functionalized silica particles). Alternatively, a monomer having a brominated aromatic functional group may be reacted with a silane to produce a brominated alkoxysilane monomer, which is then reacted with the surface of silica particles.
例如,具有
溴化
硅颗粒的阻燃填料可为印刷电路板(PCB)、连接器和其他采用热固性塑料或热塑性塑料的制成品提供阻燃性。在此示例中,
溴化
硅颗粒既可作为流变控制(粘度、流动性等)的填料,也可作为阻燃剂。在一个示例应用中,PCB 层压叠片包括由介电材料分隔的导电平面,介电材料包括由
溴化
硅颗粒组成的阻燃填料。在合成
溴化
二氧化硅颗粒的一种示例方法中,具有
溴化芳香族官能团的单体与官能化
二氧化硅颗粒(如
异氰酸酯、
乙烯基、胺或环氧官能化
二氧化硅颗粒)反应。或者,具有
溴化芳香族官能团的单体可与
硅烷反应,生成
溴化烷氧基
硅烷单体,然后与
二氧化硅颗粒表面反应。