Normally, phosphate ester FRs such as BDP, RDP and so on are used at a relatively large dosage for formulation of halogen-free flame retardant PC/ABS to meet UL94 V0. The large amount of phosphate ester FR that is used leads to two issues. Firstly, the overall cost is relatively high. Secondly, the heat deflection temperature (HDT) is significantly reduced. Additional use of PCF-2160 at a dosage of around 0.2% can dramatically reduce the dosage of the phosphate ester FR without sacrifice in flame-retarding efficiency, thus reducing the overall cost and increasing HDT.