Akamatsu Masaaki, FitzGerald Paul A, Shiina Mayu, Misono Takeshi, Tsuchiya Koji, Sakai Kenichi, Abe Masahiko, Warr Gregory G, Sakai Hideki
†Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-0022, Japan.
‡School of Chemistry, F11, The University of Sydney, New South Wales 2006, Australia.
J Phys Chem B. 2015 May 7;119(18):5904-10. doi: 10.1021/acs.jpcb.5b00499. Epub 2015 Apr 24.
Photoresponsive micellar systems of 4-butylazobenzene-4'- (oxyethyl)trimethylammonium bromide (AZTMA) were examined with and without ethylbenzene using small-angle neutron scattering (SANS). Analysis of SANS profiles showed that an aqueous solution containing 5, 10, and 50 mM AZTMA forms prolate spheroids with a long radius (Ra) of 38 Å and a short radius (Rb) of 21 Å. In the 5 mM AZTMA solution, the concentration of micelles decreased upon UV light irradiation, while their size and shape remained almost unchanged. Subsequent visible light irradiation reversed the decrease and increased the number of micelles. In contrast, 10 and 50 mM AZTMA solutions showed that the number and long radius of the micelles decreased with UV light irradiation, while subsequent exposure to visible light irradiation restored them. For AZTMA micellar solutions equilibrated with excess ethylbenzene, the solubilized amount of ethylbenzene increased upon UV light irradiation due to enhanced swelling of the micelles with cis-AZTMA. This photoinduced uptake of the solubilizate has potential applicability for the collection and removal of hazardous oily substances.
使用小角中子散射（SANS）对4-丁基偶氮苯-4'-（氧乙基）三甲基溴化铵（AZTMA）的光响应胶束体系进行了有无乙苯存在情况下的研究。SANS图谱分析表明，含有5 mM、10 mM和50 mM AZTMA的水溶液形成了长半径（Ra）为38 Å、短半径（Rb）为21 Å的扁长球体。在5 mM AZTMA溶液中，紫外光照射后胶束浓度降低，但其尺寸和形状几乎保持不变。随后的可见光照射使降低的浓度逆转，胶束数量增加。相比之下，10 mM和50 mM AZTMA溶液显示，紫外光照射下胶束的数量和长半径减小，而随后暴露于可见光照射下又使其恢复。对于与过量乙苯平衡的AZTMA胶束溶液，由于顺式AZTMA使胶束膨胀增强，紫外光照射后乙苯的增溶量增加。这种光诱导的增溶物摄取对于收集和去除有害油性物质具有潜在的适用性。
