Inorganic dopants in polymer cholesteric liquid crystals

Anka Trajkovska


A variety of dopants are used for different types of polymers to change their properties. Inorganic dopants are usually used to change the dielectric properties of the polymers. These compositions find different applications especially in electronic systems due to ease of polymer processing, increased functionality and low cost of novel materials that are with relatively high dielectric constant compared to the base polymer material.

In this study, polymer cholesteric liquid crystal (PCLC) is used as a host material that is doped by different inorganic dopants, BaTiO3 and TiO2, all of them affected the dielectric constant of the polymer matrix. This is important from the fact that doped PCLC can be used for a variety of electro-optical applications, e.g. display applications and low energy consuming e-book application. The behaviour of inorganic dopants in PCLC is calculated by various existing mixing models; the best fit is observed by use of logarithmic equation.


polymer cholesteric liquid crystals, inorganic dopants, BaTiO3, TiO2

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