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Transition of phase-separated PBTPA/PMMA solution droplets from core–shell to Janus morphology under UV light irradiation


Here, we report the morphological transition of a phase-separated structure from core–shell to Janus morphology in droplets consisting of a poly(4-butyltriphenylamine) (PBTPA)/poly(methyl methacrylate) (PMMA) blend solution, induced by UV light irradiation. We obtained a phase-separated structure formed by the evaporation of the solvent from polymer solution droplets dispersed in an aqueous solution containing a surfactant. The rate of transition decreased with increasing polymer concentration and diameter of the droplet. It was also found that the transition was caused by UV light with a wavelength of 365 nm, which is mainly absorbed by PBTPA, indicating that this phenomenon is triggered by PBTPA. When the droplet was heated to 75 °C, no transition was observed.

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We thank Dr. Tei Maki (The Research Center for Science and Technology/JEOL Ltd.) for assistance with TEM imaging.

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Correspondence to Shinji Kanehashi or Kenji Ogino.

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The authors declare that they have no conflict of interest.

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Kikuchi, S., Kanehashi, S. & Ogino, K. Transition of phase-separated PBTPA/PMMA solution droplets from core–shell to Janus morphology under UV light irradiation. Polym J 50, 1089–1092 (2018).

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