Title: Photo-Induced Bending Behavior of Post-Crosslinked Liquid Crystalline Polymer/Polyurethane Blend Films

Author: Xinlei Pang, Bo Xu, Xin Qing, Jia Wei*, Yanlei Yu*

Journal: Macromol. Rapid Commun., 2018, 39(1), 1700237

Abstract:

Photoresponsive blend films with post-crosslinked liquid crystalline polymer (CLCP) as a photosensitive component and flexible polyurethane (PU) as the matrix are successfully fabricated. After being uniaxially stretched, even at low concentration, the azobenzene-containing CLCP effectively transfers its photoresponsiveness to the photoinert PU matrix, resulting in the fast photo-induced bending behavior of whole blend film thanks to the effective dispersion of CLCP. Specifically, the blend film shows photo-induced deformations upon exposure to unpolarized UV light at ambient temperature. The film unbends after thermal treatment, and the randomly orientated mesogens in the film can be realigned by the mechanical stretching, which endows the film with a reversible deformation behavior. The photosensitive blend film possesses favorable mechanical property and good processability at low cost, and it is a promising candidate for a new generation of actuators.

论文链接：https://onlinelibrary.wiley.com/doi/full/10.1002/marc.201700237

PDF下载：Photo-Induced Bending Behavior of Post-Crosslinked Liquid Crystalline PolymerPolyurethane Blend Films.pdf

在这项工作中，我们通过将N-羟基琥珀酰亚胺羧酸盐取代的偶氮苯可交联PAZO结合到柔性聚氨酯(PU)中，成功制备了以后交联液晶聚合物（CLCP）为光敏组分，以柔性聚氨酯（PU）为基体的光响应共混薄膜。由于CLCP在PU基体中的有效分散，即使在低强度紫外线（365 nm）照射下，排列的偶氮苯部分引起的微小体积变化也可以放大到整个共混体系。值得注意的是，PAZO含量较低的共混膜（PAZO/PU = 1.7/98.3）在环境温度下暴露于紫外光时也能够发生快速的光致弯曲行为。