Reverse-mode polymer dispersed liquid crystal films prepared by patterned polymer walls

Abstract

This article proposes a methodology to prepare polymer dispersed liquid crystal (PDLC) films working in the reverse-mode operation, where the ion-doped nematic liquid crystals (NLCs) with negative dielectric anisotropy (Δε) were locked by polymer walls. On-state and off-state of films were controlled by an electric field. In the absence of an electric field, it appears to be transparent. In the field, the homogeneous alignment NLCs form dynamic scattering, giving rise to opaque. The effect of the cylindrical holes with different diameters of photo masks and liquid crystal Δε on the electro-optical properties and transmittance wavelength range of 400–3000 nm light of samples were investigated. It was found that it exhibited very good electro-optical characteristics, high contrast ratio and excellent infrared energy-efficient of films used as switchable windows.

Keywords:

• reverse-mode polymer dispersed liquid crystal
• polymer walls
• nematic liquid crystal
• negative dielectric anisotropy
• electro-optical properties

Additional information

Funding

This work was supported by the Sino-American Cooperative Project of Chinese Ministry of Science and Technology [grant number 2013DFB50340], the Major Project of Beijing Science & Technology Program [grant number Z121100006512002], the Major Program of Chinese Ministry of Education [grant number 313002], the Doctoral Fund of Chinese Ministry of Education [grant number 20120001130005], China Postdoctoral Science Foundation funded project [grant number 2013M540017], National Natural Science Foundation [grant number 51473020] and Fundamental Research Funds for the Central Universities [grant number FRF-TP-14-001A2].