Liu Long, Bai Jinhu, Su Ze, Yao Yuan, Zhou Zhixiang, Xia Yangfeng, Zhang Yanqiang
Key Laboratory of Science and Technology on Particle Materials, Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100049, China.
Zhengzhou Institute of Emerging Industrial Technology, Zhengzhou 450000, China.
ACS Omega. 2023 May 1;8(19):16738-16747. doi: 10.1021/acsomega.3c00256. eCollection 2023 May 16.
In this paper, a series of energetic ionic liquid plasticizers of 1-methyl-4-methoxyethyl-1,2,4-triazolium chloride (), 1-methyl-4-methoxyethyl-1,2,4-triazolium bis(trifluoromethylsulfonyl)imide (), 1-methyl-4-methoxyethyl-1,2,4-triazolium nitrate (), 1-methyl-4-ethyl acetate-1,2,4-triazolium chloride (), 1-methyl-4-ethyl acetate-1,2,4-triazolium bis(trifluoromethylsulfonyl)imide (), and 1-methyl-4-ethyl acetate-1,2,4-triazolium nitrate () were synthesized and characterized. The results show that compounds , , , and have lower melting points (, -72.60 to -32.67 °C) and good thermal stability (, 161-348 °C) and are suitable as plasticizers for hydroxyl-terminated polybutadiene (HTPB) curing systems. Among these four ionic liquids, ester-functionalized cations can help to improve the tensile strength (, 0.943 MPa; , 1.113 MPa) of the cured system, while ether-functionalized cations are more beneficial to improve elongation at break (, 522.90%; , 484.45%). Ester-functionalized ionic liquids are more beneficial to reduce the glass transition temperature of HTPB elastomers. The storage modulus of HTPB elastomers containing NO is higher, while that of HTPB elastomers containing NTf is lower. The crosslink densities of HTPB/TDI/ and HTPB/TDI/ plasticized by ester-functionalized ionic liquids are larger, which are 9369 and 9616 mol/m, respectively. There are hydrogen bond interactions between the ionic liquid and the HTPB elastomer, and these interactions changed the distribution of the hard and soft segments in the polymer molecules.
本文合成并表征了一系列含能离子液体增塑剂，包括1-甲基-4-甲氧基乙基-1,2,4-三唑鎓氯化物、1-甲基-4-甲氧基乙基-1,2,4-三唑鎓双（三氟甲基磺酰）亚胺、1-甲基-4-甲氧基乙基-1,2,4-三唑鎓硝酸盐、1-甲基-4-乙酸乙酯-1,2,4-三唑鎓氯化物、1-甲基-4-乙酸乙酯-1,2,4-三唑鎓双（三氟甲基磺酰）亚胺和1-甲基-4-乙酸乙酯-1,2,4-三唑鎓硝酸盐。结果表明，化合物、、和具有较低的熔点（、-72.60至-32.67℃）和良好的热稳定性（、161-348℃），适合作为端羟基聚丁二烯（HTPB）固化体系的增塑剂。在这四种离子液体中，酯官能化阳离子有助于提高固化体系的拉伸强度（、0.943MPa；、1.113MPa），而醚官能化阳离子更有利于提高断裂伸长率（、522.90%；、484.45%）。酯官能化离子液体更有利于降低HTPB弹性体的玻璃化转变温度。含NO的HTPB弹性体的储能模量较高，而含NTf的HTPB弹性体的储能模量较低。酯官能化离子液体增塑的HTPB/TDI/和HTPB/TDI/的交联密度较大，分别为9369和9616mol/m。离子液体与HTPB弹性体之间存在氢键相互作用，这些相互作用改变了聚合物分子中硬段和软段的分布。
