Thermophysical behaviour of monofunctional acrylate and liquid crystal systems

The phase behavior of monofunctional acrylate and low molecular weight nematic liquid crystals (LC) is considered. Systems involving the monomeric 2-ethylhexylacrylate (2-EHA), the eutectic LC mixture known as E7 and the 4-cyano-4^′-n-pentyl-biphenyl (5CB) are investigated. A similar investigation is performed on mixtures involving a polymer poly-2-EHA with molecular weight M_w=48,000 g/mol and both LCs. The experimental phase diagrams are established using polarized optical microscopy and analyzed using a theoretical formalism which combines the Flory-Huggins theory of isotropic mixing and the Maier-Saupe theory of nematic order. The results lead to characterization of the miscibility of E7 and 5CB with monomeric and analogous polymeric 2-EHA systems.