Liquid crystal elastomers exhibit several interesting phenomena like elastic response, shape memory effect and mechanical actuation triggered by external stimuli and have got much importance among all types of actuated materials. In the present study, we synthesised nematic liquid crystal elastomers (NLCEs) by using Finkelmann procedure. The chemical structure of elastomers is confirmed by Fourier transform infrared spectroscopy. The dielectric response of NLCEs and the monomer used in its synthesis has been studied in the frequency range 20 Hz to 1 MHz. The effect of bias on dielectric response of NLCE and its comparison with its liquid crystal analogue is also reported.

In the present study, the optical, thermal, and mechanical properties of liquid crystal elastomers (LCEs) were investigated using various techniques. The presence of functional groups in LCE was studied using Fourier transform infrared spectroscopy. The phase transition temperatures were confirmed via polarizing optical microscopy and Fabry-Perot scattering studies. The differential thermal analysis was used for investigating the thermal behavior. A dynamic mechanical analysis was used to study the mechanical properties of LCE. The significant mechanical changes with a considerable reversible effect were observed for this soft material. The changes in the mechanical shape with the temperature are attributed to the change in the phase of the LCE material. ARTICLE HISTORY

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Polyaniline (PANI) synthesized through the in situ polymerization method and its composites with zinc oxide nanoparticles loaded in various weight percentages were studied. The formation of PANI and its composites was characterized using different characterizing tools, and detailed analysis was done to investigate the structural and morphological properties of the composites. The presence of the vibration band of the metal oxide and other characteristic bands of the composites, as characterized via Fourier transmission infrared spectroscopy, confirmed the synthesis of the polymer nanocomposites. The X-ray diffraction patterns of the nanocomposites revealed their polycrystalline nature. The dielectric responses of PANI and the ZnO-doped PANI composites were investigated within the frequency range of 20 Hz to 1 MHz. The dielectric constant of the ZnO-doped PANI composite was found to be higher than that of the pure PANI. The value of the dielectric constant decreased with increasing frequency, and it became constant at higher frequencies, which is attributed to the interfacial polarization.