Synthesis and Characterization of Liquid Crystal Elastomer

Abstract

The thermal and mechanical properties of Liquid Crystal Elastomers (LCEs) were characterized using various techniques for understanding of their physical behavior. The material used for investigation was synthesized by us, using Finklemann procedure, with proper cross linking density in nematic phase. The material is found to have unique coupling between anisotropicorder of liquid crystal component and elasticity of polymer network. The chemical structures were confirmed by Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy (SEM). Fabry Perot Scattering Studies (FPSS), Thermo gravimetric Analysis (TGA) and Differential Scanning Calorimatory (DSC) were used to study thermal properties. The mechanical properties were studied using force sensor. Our investigation shows that this synthesized Liquid Crystal Elastomer has ability of spontaneous change as a function of temperature and mechanical force, which shows it as a unique class of soft material.

Adhesion, roughness, wettability, and dielectric strength of elastomers liquid blends for high-density fiberboard wood adhesive

“…The main peaks were observed for the EL/AG blend in the FTIR the band O-H..O stretching at 3436.9, and 3286.4 cm −1 , sp² C-H stretching corresponding to 3213.1 cm −1 , sp³ C-H stretching corresponding to 2960 cm −1 , C-H stretching at 2341 cm −1 , C=C at 1413.7, and 1639.3 cm −1 , C-O-C bending vibrations at 1170, 800.4, 642.2, and 522 cm −1 . These observed peaks represent the fingerprint area for EL/AG which agrees with [14]. For the EL/D polymer, peaks at 3438.8 cm −1 are related to the OH group's stretching vibrations in the dextrin molecules.…”

“…1 cm −1 corresponding to sp C-H stretching, at 2999. 1 cm −1 is due to a long chain of -CH2group, at 2879 cm −1 is due to C=C group, and at 646,1012.5 cm −1 is due to C-O, which is commonly used as the fingerprint region of LR, which agrees with [14].…”

Reducing the actuation threshold by incorporating a nonliquid crystal chain into a liquid crystal elastomer

“…A classical polysiloxane sidechain LCE, based on the hydrosilylation of polyhydrogen methylsilxoane (PMHS) with 4-methoxy-1-buteneoxy phenyl (MBB) as mesogen and 1,4-alkeneoxybenzene (11UB) as crosslinker, has been originally developed by Finkelmann and co-workers, 39 and extensively studied in characteristics and explored in application over the years. 10,12,26,27,29,31,[40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58] In this work, we investigated the effect of nonliquid crystal chain on the reduction of T ni by linking a nonliquid crystal side chain, 4-methoxyphenyl-1-hexenyloxy (MOCH 3 ), to the network backbone of this polysiloxane side-chain LCE. Based on the hydrosilylation of PMHS with MBB, MOCH 3 and 11UB, the synthesized network of the modied LCE contained mesogens and nonliquid crystal side chains linked to the polymer backbone.…”

Muscular MEMS—the engineering of liquid crystal elastomer actuators

“…Compared to other types of nematic LCEs, fabrication of side-chain LCEs is relatively easy [31] and they have potential for integration into established processes since structuring and orientation can be achieved by lithographic means [32]. With only very limited basic research concerning the thermo-mechanical properties of LCEs extant [33,34], we present extensive fundamental material data which facilitates actuator design with LCEs for a specific application. To conclude, we demonstrate a tunable elastomeric lens using these actuators, underlining their utility.…”