Temperature and frequency dependence on dielectric permittivity and electrical conductivity of recycled Liquid Crystals

[Display omitted] •A large number of End-Of-Life (EOL)-Liquid Crystals Displays (LCD) (65700) was used to extract the LCs mixtures.•Dielectric measurements were carried out over a wide range of frequencies (0.1 to 106 Hz) and temperatures (100 to −20 °C).•Dielectric and electrical properties of recycled nematic LC mixtures were determined.•The frequency and temperature evolution of the spectra recorded for recycled LCs were found comparable to those of commercial LCs. The dielectric behavior and the electrical conductivity response of recycled nematic Liquid Crystals (LCs) were studied over a wide range of frequencies (0.1 to 106 Hz) and temperatures (100 to −20 °C) with a broadband dielectric spectroscopy technique. These LC mixtures were extracted from a total of 65700 End-Of-Life (EOL)-Liquid Crystals Displays (LCD) such as computers, tablets and TVs of various sizes, brands, and production years. After a stage of purification, the recycled LC blends seemed to possess similar physical properties as conventional nematic LCs. In this report, two types of anchoring of LC molecules, obtained with homeotropic or homogeneous alignment cells, were investigated. All dielectric data were analyzed with adapted models: Havriliak-Negami and Almond West formalisms for the frequency dependence of the data, as well as Arrhenius and Vogel-Fulcher-Tammann models for their temperature dependence. In this article, it is demonstrated that despite the wide variety of EOL-LCD devices used leading to a large number of LC molecules, the frequency and temperature evolution of the recorded spectra are comparable to those of commercial LC mixtures as reported in the literature. Therefore, their future reuse could be envisaged for display applications.