Research Progress on the Expansion Performance and Char Strength of Intumescent Fire-retardant Coatings
LI Yibo1,2, ZHANG Ling1,2, LIANG Zhixia2, ZHANG Donghai2,*
1 School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China; 2 State Key Laboratory of Mesoscience and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
Abstract: Intumescent fire-retardant coating(IFRC), as a functional composite material, is widely applied in steel-structured buildings. The fire protection of IFRC depends on its expansion and the strength of the char layer, although it is often hard to get both at the same time. Although research on improving the fire protection of IFRC has progressed, there is still a lack of works that systematically summarize strategies for improving both expansion and char strength. This review provides a categorized overview based on IFRC composition, working mechanisms, and recent studies on filler and resin modification. We first provide a systematic discussion of the core components of IFRC, including the intumescent flame-retardant (IFR) system, resin matrix, and fillers, with a detailed explanation of the synergistic mechanisms among these components. Subsequently, filler optimization strategies of expansion performance and char strength are summarized. The resulting compatibility issues between fil-lers and the resin matrix are also discussed along with potential solutions. Finally, modification strategies for the resin matrix are categorized, and future research directions for improving the expansion and carbonization performance of IFRC are proposed.
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