硫醇含量对蓝相液晶弹性体性能的影响

Thiol content effect on properties of blue phase liquid crystal elastomers

蓝相液晶弹性体(BPEs)是一种集三维光子晶体结构与橡胶软弹性于一身的功能材料,在液晶光子学领域具有广泛的应用前景,但是新型BPEs的制备方法及其弹性性能有待进一步研究。本文在原位光聚合的基础上,引入硫醇(EDDET)和丙烯酸酯之间的点击化学反应制备了不同EDDET含量的BPE薄膜,系统研究了EDDET含量和光固化对BP晶格结构、热稳定性和光学特性的影响,并测量了EDDET含量不同的BPE的弹性性能和力致变色性能。试验结果表明,EDDET可以有效填充BP的缺陷结构,随着含量的增加,BP的热稳定性提高了5倍。光固化过程中会诱导BP晶格形变,随EDDET含量增加,BPE薄膜的断裂长度可以提高7倍,布拉格反射峰移动量相同时,应力减小约52倍。通过该方法制备的BPE在智能仿生、传感、防伪、激光等领域具有广泛的应用前景。

Blue phase liquid crystal elastomer(BPE)is a functional material integrating three-dimensional photonic crystal structure and rubber soft elasticity and has a wide application prospect in the field of liquid crystal photonics.However,the novel preparation method and elastic properties of BPEs need to be further investigated.On the basis of in-situ photopolymerization,BPE films with different mercaptan(EDDET)contents were prepared by introducing the click chemical reaction between EDDET and acrylate.The influence of EDDET content and UV curing on the lattice structure,thermal stability and optical properties of BP were systematically studied,in ddiion,the elastic properties and stress color change properties of BPE prepared with different EDDET concent were measured.The experimental results show that EDDET could effectively fill the disclination network of BP.With the increase of EDDET content,the thermal stability of BP was increased by 5 times.The UV light curing process would induce BP lattice deformation.As the EDDET content increased,the fracture length of BPE film was increased by 7 times,and the stress decreases by about 52 times with the same change of the Bragg reflection peak of BP.We believe that the BPE films prepared by this method has a wide application in the fields of intelligent bionics,sensing,anti-counterfeiting,lasing and so on.