An electrically switchable surface free energy on a liquid crystal and polymer composite film

Abstract

An electrically switchable surface free energy on a liquid crystal and polymer composite film (LCPCF) resulting from the orientations of liquid crystal molecules is investigated. By modification of Cassie's model and the measurement based on the Chibowski's film pressure model (E. Chibowski, Adv. Colloid Interface Sci. 103, 149 (2003)), the surface free energy of LCPCF is electrically switchable from 36 x 10(-3)J/m(2) to 51 x 10(-3)J/m(2) while the average tilt angle of LC molecules changes from 0 degrees to 32 degrees with the applied pulsed voltage. The switchable surface free energy of LCPCF can help us to design biosensors and photonics devices, such as electro-optical switches, blood sensors, and sperm testers. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4769093]