A novel hybrid material of ZIF‐8/RGO (zeolitic imidazolate frameworks‐8 loaded the surface of graphene) was synthesised by a simple method and characterized. Then, ZIF‐8/RGO was added into epoxy resin (EP), and the flame retardancy and smoke suppression of the EP composites were studied. Compared with pure EP, the peak heat release rate and the total heat release of the EP composites were reduced remarkably, and their LOI and UL94 vertical burning rating were also improved. In addition, their smoke production rate and total smoke production were decreased drastically. The improved flame retardancy and smoke suppression were mainly attributed to the physical barrier effect of graphene. Meanwhile, the metal oxide decomposed from ZIF‐8 could contribute to the production of char residue and enhance the compactness of the char layer.

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Molybdenum trioxide (MoO3)-loaded graphene (MoO3-GNS) hybrids and cuprous oxide (Cu2O)-loaded graphene (Cu2O-GNS) hybrids were successfully prepared via the hydrothermal method and one-pot coprecipitation method, respectively. Subsequently, the MoO3-GNS and Cu2O-GNS hybrids were incorporated into a polyurethane elastomer (PUE) matrix, respectively, and their effects on thermal stability, flame retardancy, and smoke suppression properties of PUE were investigated. Thermogravimetric analysis results showed that the incorporation of 2.0 wt % MoO3-GNS or Cu2O-GNS hybrids efficiently improved the char yield of the PUE matrix. Moreover, the addition of MoO3-GNS or Cu2O-GNS hybrids presented excellent flame retardancy and smoke suppression properties of PUE composites, as evidenced by the obvious reduction in their heat release rate, total heat release, and smoke density. The improvement in the flame retardancy and smoke suppression properties were mainly attributed to the synergistic effect between the physical barrier effect of graphene sheets and the catalytic charring effect of MoO3 or Cu2O.

MgAl layered double hydroxides (LDHs) containing tripolyphosphate (P 3 O 10 5−) (P-LDHs) were prepared by the anion exchange method; subsequently, aminopropyltriethoxysilane (APTS) was grafted onto the surface of P-LDHs to prepare S-MgAl LDHs (S-LDHs) through induced hydrolysis silylation. The dispersion, flame retardancy, and smoke suppression of N-LDHs (MgAl LDHs with nitrate in its interlayer), P-LDHs, and S-LDHs in polyurethane elastomer (PUE) were investigated. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) showed that S-LDHs could disperse uniformly in PUE. The cone calorimetry and smoke density test indicated that S-LDHs performed best in flame retardancy and smoke suppression. By analyzing the char layer with Laser Raman spectroscopy (LRS), Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), it could be concluded that, besides the catalytic charring effect of LDHs, the stable structure of −P(O)−O−C− and −P(O)−O−Si− could improve the thermal oxidative resistance and stabilize the char layer, resulting in better flame retardancy and smoke suppression.

A novel type of ZIF‐8/α‐ZrP (zeolitic imidazolate frameworks‐8/α‐zirconium phosphate) hybrid was obtained through surface modification of α‐ZrP by ZIF‐8 and was characterized. Subsequently, ZIF‐8/α‐ZrP was added to polyurethane elastomer (PUE) by simple blending, and the thermal behavior, flame retardancy, and smoke suppression properties of the ZIF‐8/α‐ZrP hybrid on PUE were studied. Compared with pure PUE, the test results showed that the char yield of the ZIF‐8/α‐ZrP/PUE composite at 700°C and its Tg values were increased, respectively. The peak heat release rate and total heat release of the ZIF‐8/α‐ZrP/PUE composite decreased by 69.6% and 45.6%, respectively. Meanwhile, its smoke production rate and total smoke production decreased by 59.3% and 40.5%, respectively. The improved flame retardancy and smoke suppression were primarily ascribed to the physical barrier and catalytic carbonization effects of α‐ZrP. Furthermore, the metal oxide decomposed by ZIF‐8 could further facilitate the production of char residue and raise the compactness of the char layer.