Search

To improve its dispersion and flame retardant efficiency, graphene oxide (GO) was modified multiple times with functional elements and the graphene-based flame retardant was endowed with catalytic carbonation ability to reduce flammability and smoke suppression of epoxy resin (EP). The graphene-based flame retardant (MZP-GO) was successfully synthesized by incorporating functional elements (phosphorus, zinc, tin, and molybdate) into graphene oxide nanosheets. Subsequently, the resulting MZP-GO was added to EP to prepare EP composites. The MZP-GO showed well-dispersed behavior in the EP matrix. After adding 2 wt% MZP-GO to the EP matrix, the fire test results showed a significant reduction in heat and smoke. Compared with pure EP, the EP composite shows a 62.9% reduction in the peak heat release rate and a 52.7% smoke production rate. Moreover, the limiting oxygen index value was improved from 25.4% to 29.7%, and the sample could easily pass the UL-94 V-0 rating. This study provides a novel strategy to fabricate high-performance flame-retardant polymer materials with expandable practical applications. [ABSTRACT FROM AUTHOR]

Despite many important industrial applications, epoxy resin (EP) suffers from high flammability and toxicity emission. To circumvent the problem, phosphorus/nitrogen compound and zinc hydroxystannate‐modified graphene oxide is successfully fabricated. The functionalized graphene (FGO) exhibits high thermal stability and excellent dispersity in the EP matrix. The storage modulus of EP/FGO2 increases to 2713 MPa from 2176 MPa. Meanwhile, the results show a significant reduction in fire, smoke, and toxicity hazards. Compared with pure EP, incorporating only 2.0 wt% FGO2 into EP, smoke production rate, the peak heat release rate, and peak carbon monoxide production are dramatically reduced by 40.1%, 40.3%, and 37.7%, respectively. Especially, the fire growth index of EP/FGO2 is reduced by 36.0%. Moreover, the limiting oxygen index value of EP/FGO2 enhances to 28.5% and its UL‐94 achieves V‐1 rating. These superior fire safety properties are due to the catalytic, barrier effect of the FGO, the compact char blocks the diffusion of smoke and heat during combustion. This work provides an efficient strategy to prepare a promising graphene‐based flame retardant to improve the fire safety and mechanical property of EP. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]