以有机蒙脱土（ OMMT）和氯化镍（ NiCl₂）作为复配协效剂制备环氧基膨胀型钢结构防火涂料，通过锥形量热仪、热重分析仪（ TG）、扫描电镜（ SEM）和傅立叶变换红外光谱（ FT-IR）系统研究了复配协效剂在防火涂料中的防火和抑烟作用。结果表明：单独添加 OMMT和 NiCl₂均能有效增强环氧基膨胀型钢结构防火涂料的隔热性能并降低燃烧过程中的生烟量和热释放，将二者复配使用表现出更好的协效作用。当 m（OMMT）∶m（NiCl₂）=1∶1时，膨胀型钢结构防火涂料的峰值热释放速率、峰值生烟速率以及 300 ℃背温时间分别为 291. 3 kW/m²、0. 039 m²/s和 1 465 s。TG结果表明， OMMT和 NiCl₂复配使用可以降低涂料的峰值分解温度和质量损失速率，使涂层在 700 ℃时的残炭率高达 24. 8%。SEM和 FT-IR结果表明， OMMT和 NiCl₂复配使用有利于形成更多含磷交联结构进而提高膨胀炭层的致密性和连续性，达到较好的防火和抑烟作用。

The epoxy-based intumescent fireproof coatings for steel structure were prepared with organic montmorillonite（OMMT）and nickel chloride（NiCl₂）as the compound synergists，and the fireproofing and smoke suppression effects of the compounding synergists in the fireproof coatings were systematically investigated by means of cone calorimeter，thermogravimetric analysis（TG）， scanning electron microscopy（SEM）and Fourier transform infrared spectroscopy（FT-IR）. The results showed that adding OMMT or NiCl₂ alone could effectively enhance the thermal insulation performance of the epoxy-based intumescentfireproof coatings for steel structure and reduce the heat release and smoke production duringthe combustion process，and the use of the two in combination showed a better synergisticeffect. When the mass ratio of OMMT and NiCl₂ was 1∶1，the backside temperature of the coated steel was 300 ℃ at 1 465 s，and the peak heat release rate and peak smoke production rate were down to 291. 3 kW/m² and 0. 039 m²/s，respectively. In addition，TG results showed that the mixture of OMMT and NiCl₂ could reduce the peak decomposition temperature and mass loss rate of the coatings，resulting in the residual carbon rate was up to 24. 8% at 700 ℃.SEM and FT-IR revealed that the combination of OMMT and NiCl₂ was conducive to the formation of more phosphorus-containing compounds to improve the densification and continuity of the expanded charcoal layer to achieve a better fire and smoke suppression effect.