Experimental study on thermal instability of imidazolium ionic liquids

doi:10.16265/j.cnki.issn1003-3033.2021.04.022

Abstract

Abstract: In order to further clarify thermal behavior of ionic liquids, experimental study was performed on their thermal instability, such as thermal decomposition and flashover, under heated conditions. Synchronous thermal analyzer and closed flash point tester were used to measure thermal decomposition temperature of 16 kinds of imidazolium ionic liquids and flash temperature of 50 kinds of them. The results show that flash temperature of imidazolium ionic liquids is related to structures and types of anions and cations with the former exerting a greater impact, and it is also affected by interaction between them, which stands for geometrical structure, size and charge distribution of ions. Moreover, there is no obvious sequence between flashover and thermal decomposition of imidazolium ionic liquids after heating, and flashover happens when combustible products generated from decomposition meet ignition sources.

Key words: imidazolium ionic liquids, thermal instability, thermal decomposition temperature, flash temperature, ionic interaction

CLC Number:

X937

WANG Gan, ZHENG Zhongyu, DUAN Weijia, PAN Yong. Experimental study on thermal instability of imidazolium ionic liquids[J]. China Safety Science Journal, 2021, 31(4): 163-170.

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