采用离子交换法,以1-丁基-3-甲基氯代咪唑([BMIM]Cl)为原料合成了咪唑醋酸盐型离子液体([BMIM]Ac),以两者为溶剂研究了胶原纤维在咪唑类离子液体中的溶解行为及再生前后的结构与热稳定性变化。结果表明,胶原纤维在CH3COO-和Cl-型离子液体中均能溶解,但具有明显不同的溶解特性。相对[BMIM]Cl的溶解性能而言,[BMIM]Ac能够在较低的温度下获得高浓度和良好流动性的胶原溶液,而且再生胶原的三股螺旋结构保留度更高。FTIR、UV、XRD、CD、TG分析结果表明,胶原在咪唑离子液体中溶解前后其化学结构未发生明显变化,而三股螺旋的保留度和热稳定性略有降低。
1-butyl-3-methylimidazolium acetate([BMIM]Ac) was synthesized from 1-butyl-3-methylimidazolium chloride([BMIM]Cl) via the ion exchange method. These imidazolium ionic liquids(ILs) were used as solvents to dissolve collagen fibers. The solubility and the change of collagen structure as well as thermal stability after dissolution and regeneration from ILs were investigated. Athough collagen fibers could be dissolved in both CH3COO- and Cl- imidazolium ionic liquids, the dissolution characteristics were quite different. Compared with [BMIM]Cl ionic liquid, [BMIM]Ac was more advantageous to achieve a collagen solution with high concentration and good fluidity at a lower temperature, especially in retaining the integrity of collagen triple helix. FTIR, UV, XRD, CD and TG analysis were used to characterize the structure and properties of collagen before and after regeneration, and the results revealed that collagen chemical structure showed almost no change, but with slightly lower thermal stability and integrity of triple helix.