Broadband reflective films with temperature response combined with thermochromic materials

ABSTRACT

Cholesteric liquid crystals that exhibit a special selective Bragg reflection to light present a unique liquid crystal phase, and among them the selective reflection property has the widest range of applications. Broadband reflective films with temperature corresponding properties were prepared by doping with UV absorbers and spin-coating thermochromic materials. The factors affecting the magnitude of reflection bandwidth were investigated by adjusting the conditions of polymerisable monomer concentration, UV absorber doping, UV light intensity, polymerisation time and temperature. The reflectance bandwidth of the best sample was broadened from 244 nm to 715 nm, and the infrared shielding efficiency was measured to be as high as 50%. The spin-coated thermochromic material can visualise the temperature change on the sample, offering the possibility of developing versatile wide-wave reflection devices.

Graphical Abstract

KEYWORDS:

• Polymer-stabilised cholesterol liquid crystal
• ultraviolet absorber
• temperature-sensitive colour-changing powder
• broadband reflection

Acknowledgments

AIP Conf. Proc. 2019;2142(1):130002The authors also thanks Dr. Yuzhen Zhao, Dr. Zemin He and Dr. Huimin Zhang of Xijing University for their help in the experimental operation in this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Anhui Provincial Natural Science Foundation [2108085J11]; National Natural Science Foundation of China [52173263]; Fundamental Research Funds for the Central Universities, Northwestern Polytechnical University [D5000210825].