Improving the flame retardancy of epoxy resin with ZIF-67@GO-PA nanohybrid as filler

Despite many important industrial applications, epoxy resin (EP) suffers from high flammability. To solve the problem, functionalized graphene oxide with Co-MOF and phytic acid (ZIF-67@GO-PA) was successfully prepared. Subsequently, 2 wt% of ZIF-67@GO-PA nano-hybrids were added into EP. Base on the fire test results, the limiting oxygen index value of EP/ZIF-67@GO-PA enhances to 29.4% and its UL-94 achieves V-0 rating. Moreover, compared with pure EP, the peak heat release rate and total release rate are dramatically decreased by 57.4% and 25.7%, respectively. In addition, the fire growth index was reduced by 64.0%. These superior fire safety properties are due to the catalytic effect of metal oxide and phosphorous compounds produced during the combustion of ZIF-67@GO-PA, and the barrier effect of the graphene oxide. Because the denser char blocks the diffusion of heat during combustion, the fire hazard of EP composites is reduced.