Preparation, characterization, and thermal properties of controllable metal–imidazole complex curing agents for epoxy resins
Preparation, characterization, and thermal properties of controllable metal–imidazole complex curing agents for epoxy resins
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可控金属-咪唑复合环氧树脂固化剂的制备、表征及热性能
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
B. Howlin
中科院分区：
文献类型：
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作者：
Julie Brown;I. Hamerton;B. Howlin
以乙氧过渡金属锰、钴、镍、铜、锌、银为过渡金属盐，制备了一系列苯基甘油醚与2-乙基-4-甲基咪唑（PGE-EMI）的环氧-咪唑加合物。这些配合物已使用光谱方法（IR, UV-Vis， 1H- NMR和13C-NMR，如适用）进行了表征，并使用高温核磁共振技术确定了它们的热稳定性。这些高温核磁共振结果表明，所研究的氯络合物（Mn2+, Co2+, Ni2+， Cu2+和Zn2+）处于平衡状态（即它们在二甲亚砜（DMSO）溶液中在高温下可逆解离），而相应的乙酸配合物则不可逆解离。对于银配合物，用热重分析（TGA）监测了解离过程，结果表明，所记录的失重与金属盐解离释放pge -咪唑配体的过程一致。金属配合物的热稳定性受到过渡金属（例如，从Mn到Zn）和阴离子（例如，从醋酸盐到氯化物）变化的影响。1H-NMR分析表明，与氯离子配合物相比，乙酸离子配合物的热解离温度降低了约10°C，表明含乙酸阴离子的PGE-EMI配合物的热稳定性低于相应的氯化物。这一发现表明，当用于固化环氧树脂时，可以对这些PGE-EMI配合物进行改性，以适应其在各种不同固化时间表中的使用。©2000 John Wiley & Sons, Inc高分子学报，32 (1):1 - 4,2000
A series of complexes incorporating the epoxy–imidazole adduct of phenyl glycidyl ether with 2-ethyl-4-methylimidazole (PGE-EMI), has been prepared with the acetato and chloro transition metal salts of Mn, Co, Ni, Cu, Zn, and Ag. These complexes have been characterized using spectroscopic methods (IR, UV-Vis, 1H- and 13C-NMR, where appropriate) and their thermal stabilities have been determined using elevated temperature NMR techniques. These high-temperature NMR results indicated that the chloro complexes studied (of Mn2+, Co2+, Ni2+, Cu2+, and Zn2+) exist in equilibrium (i.e., they dissociate reversibly in a solution of dimethylsulphoxide, DMSO, at elevated temperatures), while the corresponding acetato complexes dissociate irreversibly. For the silver complexes, thermogravimetric analysis (TGA) was used to monitor the dissociation, showing that the weight loss recorded was consistent with the dissociation of the metal salt to liberate the PGE–imidazole ligand. The thermal stabilities of the metal complexes were influenced by changing both the transition metal (e.g., from Mn to Zn) and varying the anion (e.g., from acetate to chloride). From 1H-NMR analysis, a decrease of ca. 10°C was observed in the thermal dissociation of the acetato complexes when compared with the chloro complexes, showing that the series of PGE-EMI complexes with acetate anions is less thermally stable than the corresponding chlorides. This finding suggests that these PGE-EMI complexes may be modified to accommodate their use in a variety of different curing schedules when used to cure epoxy resins. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 201–217, 2000