Study on fire retardant mechanism of nano-LDHs in intumescent system

• Published in: Science China. Chemistry Vol. 50; no. 3; pp. 392 - 396
• Main Authors: Zhang, ZeJiang, Lan, Bin, Mei, XiuJuan, Xu, ChengHua
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer Nature B.V 01.06.2007; Sichuan Fire Research Institute of Ministry of Public Security, Dujiangyan 611830, China%The Department of Environmental Engineering, Chengdu University of Information Technology, Chengdu 610225,China
• Subjects: Carbon compounds; Flame retardants; Graphitization; High temperature; Oxidation; Oxygen; nanometer; intumescent system; fire-retardant mechanism; layer double hydroxides (LDHs)
• ISSN: 1006-9291; 1674-7291; 1862-2771; 1869-1870
• DOI: 10.1007/s11426-007-0072-2

This paper investigated the fire-retardant mechanism of the nano-LDHs in the intumescent system by the temperature programmed oxidation (TPO). Researches were also conducted to explore the function of the nano-LDHs in the composite fire-retardant agents in air and nitrogen atmosphere, respectively. The results indicated that the nano-LDHs species were responsible for the catalytic oxidation of the rich-carbon compound in oxygen atmosphere. In addition, the nano-LDHs species and their calcinated products at high temperature could increase the carbonaceous residue-shield of the carbon-rich materials, improve the quality and the graphitization degree of the formed char-layer, and accelerate the intumescence and expansion of the melting carbon-rich materials to a certain degree under the oxygen-free condition, leading to the carbonization and expansion of the intumescent layer.