Preparation of Boron‐Doped Cerium Phenylphosphonate and Its Enhancement on Flame Retardancy of Epoxy Resin

ABSTRACT Boron‐doped cerium phenylphosphonate hybrid (B‐CeHPP) was prepared by introducing boron into CeHPP through hydrothermal method to enhance the flame retardancy of epoxy resin (EP). The scanning electron microscope displayed that CeHPP was flower‐like, and boron was evenly distributed on the surface of the flower‐like CeHPP. In addition, the EP composites modified by CeHPP and B‐CeHPP were prepared by curing. The flame retardancy test results show that EP/B‐CeHPP composites have a higher LOI value, lower total heat release (THR), and total smoke production (TSP) value. When 8% of B‐CeHPP is added to the EP composites, compared with pure EP, the LOI value reached 33.6, passing the UL‐94 V0 class, and the peak heat release rate (PHRR), THR, and TSP were reduced by 61.0%, 54.6%, and 44.1%, respectively. The TG‐FTIR, XRD, SEM, and Raman were used to detect the pyrolysis products and the residue after combustion; we found that the enhancement of flame retardancy of EP composites can be attributed to the multiple effects of B‐CeHPP in gas and condensed phase.