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Reversible Thermochromic Photonic Coatings with a Protective Topcoat.

ABSTRACT: The fabrication of reversible and robust thermochromic coatings remains challenging. In this work, a temperature-responsive photonic coating with a protective topcoat is fabricated. A cholesteric oligosiloxane liquid crystal possessing a smectic-to-cholesteric phase-transition temperature response is synthesized. A planar alignment of its cholesteric phase is possible with blade coating. By stabilizing with 3 wt % of a crosslinked liquid crystal network, the photonic coating shows a color change ranging from red to blue upon heating. High transparency is retained, and the structural color changes are fully reversible. A transparent polysiloxane layer can be directly applied on top of the cholesteric layer to protect it against damage without affecting its optical properties. This approach satisfies the basic requirements of thermochromic polymer coatings, as it combines easy processability, coating robustness, and a reversible temperature response.

SUBMITTER: Zhang W

PROVIDER: S-EPMC7821277 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Reversible Thermochromic Photonic Coatings with a Protective Topcoat.

Zhang Weixin W Schenning Albert P H J APHJ Kragt Augustinus J J AJJ Zhou Guofu G de Haan Laurens T LT

ACS applied materials & interfaces 20210106 2

The fabrication of reversible and robust thermochromic coatings remains challenging. In this work, a temperature-responsive photonic coating with a protective topcoat is fabricated. A cholesteric oligosiloxane liquid crystal possessing a smectic-to-cholesteric phase-transition temperature response is synthesized. A planar alignment of its cholesteric phase is possible with blade coating. By stabilizing with 3 wt % of a crosslinked liquid crystal network, the photonic coating shows a color change ...[more]

PMID: 33406827

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