Thermotropic Liquid Crystalline Phases and Device Parameters of Schiff-Base Compounds: Synthesis, Characterization, and Image Processing

Abstract

Synthesis, characterization, and image processing of a new series of N (p-n-Nonyloxy benzylidene) p-n- Alkyl Aniline (9O.m; m = 4,7,9) compounds by varying the alkyl chain length have been reported. The objective was to identify the liquid crystalline phases and compare the device parameters of these compounds with respect to the increase in alkyl chain length. The characterization of these compounds was performed by UV spectroscopy, Fourier-Transform Infrared (FT-IR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. The phase behavior was explored using Polarized Optical Microscopy (POM) and Differential Scanning Calorimetry (DSC). The smectic textures observed at various temperatures were analyzed and compared. The transition temperatures, thermal stability factor, order of phase transition have been reported. Furthermore, image processing studies were performed using MATLAB software. The reported image descriptors are helpful in device manufacturing for accurate texture analysis and real-time quality control during display device production. Based on various characterizations and parameters, a superior molecule was concluded for the device architecture.