Scholarlink

<p>Photo-induced tuning of lower critical solution temperature (LCST) behavior is an attractive route for reversible phase control, yet the achievable cloud-point shift is often modest in conventional solvent systems. Here, we demonstrate a composition-amplified, light-tunable LCST in ionic liquid polymer solutions using random copolymers of 4-phenylazophenyl methacrylate and phenethyl methacrylate (P(AzoMA-<i>r</i>-PhEtMA)) dissolved in 1-ethyl-3-methylimidazolium trifluoromethylsulfonylimide ([C<sub>2</sub>mim][TFSI]), a medium in which the azobenzene-containing monomer is readily compatible. Turbidity measurements reveal opposite cloud-point shifts under UV (<i>cis</i>-type) and visible-light (<i>trans</i>-type) conditions, enabling a bistable temperature window that widens monotonically with azobenzene composition. At 37 °C, the solution is reversibly switched between one-phase and two-phase states by light alone and maintains stable cycling for more than ~40,500 s. These results provide a practical molecular design guideline for targeting ambient-to-physiological light-controlled phase separation in nonvolatile ionic liquid media.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Light-switchable LCST windows in an ionic liquid solution of azobenzene copolymers

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年5月13日

查看全文
  • Tsubasa Naka,
  • Takeshi Ueki

摘要

Photo-induced tuning of lower critical solution temperature (LCST) behavior is an attractive route for reversible phase control, yet the achievable cloud-point shift is often modest in conventional solvent systems. Here, we demonstrate a composition-amplified, light-tunable LCST in ionic liquid polymer solutions using random copolymers of 4-phenylazophenyl methacrylate and phenethyl methacrylate (P(AzoMA-r-PhEtMA)) dissolved in 1-ethyl-3-methylimidazolium trifluoromethylsulfonylimide ([C2mim][TFSI]), a medium in which the azobenzene-containing monomer is readily compatible. Turbidity measurements reveal opposite cloud-point shifts under UV (cis-type) and visible-light (trans-type) conditions, enabling a bistable temperature window that widens monotonically with azobenzene composition. At 37 °C, the solution is reversibly switched between one-phase and two-phase states by light alone and maintains stable cycling for more than ~40,500 s. These results provide a practical molecular design guideline for targeting ambient-to-physiological light-controlled phase separation in nonvolatile ionic liquid media.