提拉纺丝制备弹性离子液体凝胶纤维

Pultrusion Spinning of Elastic Ionogel Fibers

规模化制备兼具高弹性和高离子电导率的可拉伸导电纤维极具挑战性.为此,我们开发了一步法提拉纺丝策略,可连续制备高弹性离子液体凝胶纤维.其中,离子液体与聚合物基质以非共价相互作用结合,在纤维中稳定存在,并可大幅调控纤维力学性能.得益于通过氢键自发纳米限域形成的多尺度相分离结构,所得离子液体凝胶纤维具有良好的拉伸性(707%)、高透明度(98%)、高回弹性(残余应变仅9%)、导电性(0.12 S·m^(-1))以及抗冻性能.此外,该纤维还可对湿气、温度以及应变表现出极为灵敏的信号感知能力.这一工作为开发面向智能感知的高性能离子导电纤维材料提供了设计思路.

Stretchable ionically conductive fibers hold great promise in the fields of flexible electronic devices,smart textiles,and human-machine interfaces.However,the scalable production of stretchable fibers with both high conductivity and elasticity remains a significant challenge.In recent years,pultrusion spinning has emerged as a promising technique for the continuous fabrication of ultrathin gel fibers at ambient conditions.Nevertheless,the reduction in fiber diameter often comes at the cost of significantly increased resistance,hampering their applications in smart sensing.To overcome this limitation,in this study,we introduce a one-step pultrusion spinning approach for the continuous production of highly elastic ionogel fibers.Our ionogel fiber is derived from a spinning dope containing poly(2-(dimethylamino)ethylacrylate)methyl chloride quarternary salt(PDMAEA-Q),poly(methacrylic acid)(PMAA),and an ionic liquid,1-ethyl-3-methylimidazolium ethyl sulfate(EMI ES).Upon water evaporation,PMAA chains undergo nanoconfinement through hydrogen bonding,forming numerous clusters dispersed within the ductile PDMAEA-Q matrix.Moreover,the employed ionic liquid,EMI ES,interacts with polymer matrix through various physical interactions,further modulating the mechanical and electric properties of the resulting fiber.Owing to its hierarchical phase-separated structure formed by spontaneous nanoconfinement,the ionogel fiber exhibits exceptional stretchability(707%elongation),remarkable transparency(98%),high elasticity(~9%residual strain),high ionic conductivity(0.12 S·m^(-1)),and anti-freezing properties.Furthermore,the ionogel fiber is sensitive to humidity,temperature,and strain changes,enabling its high-resolution detection of different stimuli via electrical signals.This work paves the way for the design of advanced ionically conductive fibers,unlocking a myriad of possibilities in smart sensing applications.