以巯基乙酸胆碱为共溶剂的角蛋白/PVA复合膜的一浴法制备及性能

One-pot Preparation and Properties of the Wool Keratin/PVA Composite Membranes with Choline-thioglycolate as Co-solvent

巯基乙酸胆碱是一种具有还原性的低共熔体系(DES),在角蛋白(KER)材料的溶解、再生以及改性方面具有较好的应用前景。本工作以巯基乙酸胆碱为共溶剂,采用一浴法同时溶解羊毛纤维和聚乙烯醇(PVA),制备了KER/PVA复合膜。利用SEM、XRD、TG以及FTIR等测试方法探究了不同组分复合膜的表面形貌、结晶性、热稳定性及角蛋白二级结构的变化。研究结果表明,角蛋白和PVA能均匀分布在复合膜中,随着PVA含量的增加,复合膜的结晶度、拉伸性能和热学性能均得到了明显的提高。此外,通过红外分峰拟合对膜的二级结构进行了分析,结果表明,相较于纯羊毛角蛋白,复合膜中α-螺旋和无规结构在PVA的诱导下向β-折叠和β-转角结构进行了转化,这有利于其结晶度的提高和材料力学性能的提升。

Choline-thioglycolate is a kind of reducing deep eutectic solvent(DES),which has a very considerable application prospect in the dissolution,regeneration and modification of keratin materials.In this study,choline-thioglycolate was used to dissolve the wool keratin and PVA in one-pot and the composite membrane was fabricated.The surface morphology,crystallinity,thermal stability,mechanical property and secondary structure of the composite membrane were investigated by test methods such as SEM,XRD,TG and FTIR.The results indicated that wool keratin and PVA were evenly distributed in the composite membrane.With the addition of PVA,the crystallinity,tensile property and thermal property of composite membrane gradually improved.Meanwhile,the secondary structure of the composite membrane was analyzed by the method of peak fitting,and the result showed that with the induction of PVA,α-helix and random coil structure in the composite membrane reduced,β-sheet andβ-turn increased compared with the raw wool keratin,which contributes to increase the crystallinity and the mechanical properties of the material.