A NONLINEAR CONSTITUTIVE MODEL FOR NEMATIC GELS

Nematic gels are materials that combine the properties of conventional gels and liquid crystals. Compared with conventional gels, nematic gels exhibit more interesting properties due to their liquid-crystalline behaviors. For example, nematic gels may deform spontaneously in response to external field, enabling them to be ideal materials for actuators and sensors. In this paper, we developed a constitutive theory of nematic gels based on free energy minimization. With the resulting theory, we modeled a miniaturized cylindrical actuator made of nematic gels and showed that the cylindrical nematic gel actuator would undergo a substantial elongation along its longitudinal direction in response to a cooling environment.