title: Solvation effects with a photoresponsive two-component 12-hydroxystearic acid-azobenzene additive organogel.
abstract: A "light-triggerable" azobenzene amine derivative (additive 1) was synthesized and then introduced into organogels of 12-hydroxystearic acid (HSA) in the molar ratio of 1:3. The organogels (HSA/1) consisting of additive 1 and HSA were analyzed by (1)H nuclear magnetic resonance (NMR), Fourier transform-infrared (FT-IR), and X-ray diffraction (XRD). The homogeneity of the gel networks was observed using field emission scanning electron microscopy (FE-SEM). Additive 1 formed a complex with HSA in HSA organogels due to salification between the terminal amine group of additive 1 and the carboxylic acid group of HSA. Additive 1 in the gels of HSA/1 showed the potential for photo-isomerization, and we achieved a reversible control of HSA/1 sol-gel transition in toluene by the alternating irradiation with UV and visible light. Interestingly, the opposite phenomenon was observed in CHCl(3) system, namely, the orange solution of HSA/1 in CHCl(3) was turned to a red-transparent gel by exposure to UV light.
authors: Department of Industrial Chemistry, Tokyo University of Science, Tokyo, Japan.
authors: Frederic
authors: F
authors: Delbecq
authors: Nobuhiro
authors: N
authors: Kaneko
authors: Hiroshi
authors: H
authors: Endo
authors: Takeshi
authors: T
authors: Kawai
mesh_terms: D002725:Chloroform; D003116:Color; D005782:Gels; D007536:Isomerism; D008027:Light; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D044367:Phase Transition; D055668:Photochemical Processes; D017550:Spectroscopy, Fourier Transform Infrared; D013229:Stearic Acids / Q000737:chemistry*; D014050:Toluene; D014466:Ultraviolet Rays; D014961:X-Ray Diffraction; D010128:p-Aminoazobenzene / Q000031:analogs & derivatives*
chemical_list: D005782:Gels; D013229:Stearic Acids; D014050:Toluene; D010128:p-Aminoazobenzene; D002725:Chloroform