New halogen-free high elastic modulus build-up material

The authors have developed a new build-up material MCF-6000G, which has high elastic modulus and has the incombustibility of UL94 level V-0 without halogenated flame retardant. Applying high Tg epoxy resin and a special fibrous filler gave high elastic modulus. The halogen free incombustible system was achieved by combining the following techniques: adoption of aromatic-ring rich resin and carbonizing catalyst; addition of suitable metal hydroxides and fibrous filler; high density filling and filler/resin interface control. MCF-6000G contains no halogen and has a high elastic modulus, high Tg, low coefficient of thermal expansion (CTE), and sufficient processability. It will be a promising environmentally-friendly material for PWBs.