Preparation of high-performance flame-retardant hybrid material by hyperbranched polyphosphate ester

A novel hyperbranched polyphosphate ester (HPPE) and a high‐performance hybrid flame‐retarding material HPPE/diglycidyl ether of bisphenol‐A (DGEBA) epoxy resin are prepared. The effect of HPPE content and molecular weight on the mechanical performance, thermal performance, and flame‐retarding property of the hybrid material is studied. The results show that the overall performance of the hybrid material first increases and then decreases with the increase of HPPE content as well as the molecular weight and reaches maximum with 8–12 wt% of HPPE. When compared with the performance of pure DGEBA, the tensile strength, flexural strength, impact strength, fracture toughness, and limited oxygen index of the HPPE‐2/DGEBA hybrid material are enhanced by about 114%, 50%, 48%, 95%, and 20%, respectively. The toughening and reinforcing mechanism of the hybrid system is a novel in situ effect as revealed by the micrographs of the fracture surfaces using scanning electron microscopy. POLYM. COMPOS., 32:36–43, 2011. © 2010 Society of Plastics Engineers