DGEBA/imidazolium ionic liquid systems: the influence of anions on the reactivity and properties of epoxy systems. Issue 10 (19th May 2018)

• Record Type: Journal Article
• Authors: Yin, Yuan; Liu, Meihua; Wei, Wei; Zheng, Changmei; Gao, Jian; Zhang, Wanxi; Zheng, Chunbai; Deng, Pengyang; Xing, Yue
• Is Part Of: Journal of adhesion science and technology. Volume 32:Issue 10(2018)
• Page Start: 1114
• Page End: 1127
• Publication Date: 2018-05-19
• Subjects: Epoxy system -- imidazolium salts -- curing agent -- reactivity and properties; Adhesion -- Periodicals; Adhesives -- Periodicals; 668.3
• DOI: 10.1080/01694243.2017.1402402
• Languages: English
• ISSNs: 0169-4243

Abstract

Abstract: Imidazolium salts containing, , , , or ionic liquids were blended with an epoxy prepolymer, dyglycidylether of bisphenol A (DGEBA) to obtain a series of compositions. To characterize the resulting mixtures and determine the influence of the imidazolium anion on the reactivity and properties of epoxy systems, we performed the following analyses and tests: (i) differential scanning calorimetry (DSC), to determine the curing reaction characteristics, (ii) in situ fourier-transform infrared spectroscopy (FTIR), to assess chemical structure changes, (iii) mechanical property testing of the hardened epoxy material, and (iv) thermogravimetric analysis (TGA). The DSC and FTIR analyses indicate that [Hmim]BF4, and [Hmim]PF6 cannot induce the epoxy ring opening reaction and thus these materials are unable to function as epoxy curing agents. In contrast, the imidazolium ionic liquids [Hmim]FeCl4, [Hmim]N(CN)2, and [Hmim]Zn2 Cl5 independently promote the epoxy ring opening reaction. TGA analyses show that the cured DGEBA/[Hmim]Zn2 Cl5 system exhibits thermal stability similar to the cured DGEBA/[Hmim]FeCl4 . These results can provide an essential reference not only for studying the synergistic effect of [C6 mim]FeCl4 /mixed-amines on the curing process of epoxy systems and the mechanism of the ring opening of epoxides with [C6 mim]FeCl4 /mixed-amines, but also for designing new epoxy curing systems.