The Effect of Magnetcic Field on the Phase Transition of Swollen Liquid Crystal Elastomers

Abstract

The effect of magnetic fields on the swelling of liquid crystal elastomers (LCE) dissolved in liquid crystal (LC) solvent have been studied. The Flory-Huggins model used to calculate the free energy of an isotropic mixing and the Maier-Saupe model used to calculate the free energy of a nematic mixing. Numerical integration method used to calculate the order parameter and the total free energy of system (consists of : nematic free energy, elastic free energy, isotropic mixing free energy and magnetic free energy) and the calculation results graphed as a function of temperatures for various magnetic fields and as function of magnetic fields for various of temperatures. We find that the magnetic field shifts the transition points towards higher temperatures, increases the energy transition, and induces an isotropic phase to paranematic phase.

Photomechanical vibration energy harvesting based on liquid crystal elastomer cantilever

“…Chemically, it is composed of a lightly crosslinked siloxane chain and the rigid, anisotropic mesogens which are covalently bound to the crosslinked siloxane chain. Therefore, LCE combines the elasticity properties of long polymeric chains with the orientational order of liquid crystal mesogens, which results in novel responses to external fields, such as thermal [9], electric [10,11], light [12,13], magnetic [14] and chemical [15] etc. These responses are fast [16] and reversible [17], leading to prospective applications like artificial muscle [18], remote controllable implement [19,20], actuators and sensors [21,22], energy harvester [2] and so on.…”

Effects of director orientation on the vibration of anisotropic nematic elastomer plates under various boundary conditions

“…Because there is a coupling between the mechanical deformation and the director, the orientational order will directly induce the shape variation of nematic elastomers [6]. Experiments have shown that the orientation order can be manipulated by electrical field [7], light [8], thermal [9], magnetic field [10], etc, and its response to external fields are fast and reversible. This unique perfomance of nematic elastomer has made it widely applied in artificial muscles [11], remote controllable implements and actuators [12,13], motors, sensors [14], and tunable optical devices [15].…”