Tuning Gel–Sol Transition Behavior of a Hydrogel Based on 12-Hydroxystearic Acid and a Long-Chain Amidoamine Derivative

Abstract

Abstract High-performance, low molecular weight gelators can be used as stimuli-responsive functional materials and soft templates for shape-controlled metal nanomaterials. In previous work, we reported that double-helical Au nanowires (NWs) can be synthesized in semi-transparent hydrogels prepared by addition of LiCl to aqueous solutions of d-12-hydroxystearic acid (HSA) and a long-chain amidoamine derivative (C18AA). In this work, we report the effect of three components, i.e., C18AA, HSA, and LiCl, on the fluidity and thermal properties of the hydrogel and the morphological structure of the gelator consisting of C18AA and HSA. We also demonstrate that gelation-degelation regulation and the gel–sol transition temperature can be controlled by tuning the concentrations of LiCl and C18AA, respectively. Further, the degelation behavior affords a gentle removal of the hydrogel soft template from double-helical Au NWs simply by washing with water.