四边简支液晶高弹体薄板光致弯曲行为分析

Analysis on Light Induced Bending Behaviour of Simple Supported Liquid Crystalline Elastomer Plate

光敏液晶弹性体在紫外光的照射下可以发生自发性的弯曲变形。基于各向同性线弹性材料小变形假设,建立了单畴向列相光敏液晶弹性体薄板的光致弯曲模型。通过定义光力矩,将光的效应引入挠度的控制方程和边界条件。均匀光照下,给出了四边简支边界条件下的挠度解析表达式,探讨了相关参数对弯曲行为的影响。均匀照射下,光场参数对单畴向列相液晶弹性体薄板弯曲的形状没有影响,其仅仅影响光致弯曲的程度,而单畴向列相液晶弹性体的指向矢取向不仅影响弯曲程度,更重要地对弯曲形状也产生很大的影响。

Photochromatic liquid crystalline elastomers can undergo spontaneous bending when they are illuminated by ultraviolet light.Based on isotropic elastic material and small deformation assumption,a bending model of monodomain nematic liquid crystalline elastomer plate was constructed.The light-induced bending governing equation and boundary conditions were developed by introducing light-induced moments.In the limit of uniform illumination,the analytical solutions of deflection for two typical boundary conditions involving free edges and simple supported edges were derived.The effects of some parameters on Gaussian curvature were studied.Upon uniform illumination,light only affects bending magnitude rather than bending shape.But the alignment of nematic director strongly affects both of them.