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In this study, novel photopolymerizable chiral hydrogen-bonded self-assembled complexes (PCHSCs) were fabricated, which were derived from photopolymerizable 4-(6-acryloyloxyhexyloxy) benzoic acid (AHBA, proton donor) and chiral pyridine derivatives (proton acceptor). Their structures were characterized by fourier transform infrared (FT-IR) and the proton nuclear magnetic resonance (1H-NMR) spectoscopy. The thermal stability, phase behaviors and helical twisted power (HTP) characteristics of the PCHSC were investigated by measuring the variable-temperature FT-IR spectrum, differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and the Cano wedge. The results demonstrate that all the PCHSCs have good thermal stability within a temperature range, and the pitch length of all the cells containing the PCHSCs increases with increasing temperature, which is due to the fact that the HTP values of all the PCHSCs decrease with an increase of temperature. What's more, the introduction of AHBA leads to chiral enhancement of the PCHSCs. Based on the above results, a polymer stabilized cholesteric liquid crystals (PSCLCs) composite with the above PCHSCs was prepared and the thermal-optical characteristics of the PSCLCs film were investigated. The results confirm that the reflective wavelength of the PSCLCs film before and after irradiation can be thermally switched to reflect green and red color from the initial state reflecting a blue/green color with the temperature increasing from 30 °C to 75 °C. On the basis of this mechanism, the novel material in this study can be used as optical/photonic paper, optical sensors and LCs displays, etc. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate a novel method for fabricating a single-layer Ch-LC film with multi-pitched photonic structure as new photonic band gap (PBG) materials by utilizing a polymer template. The polymer template with helical structure was originated from polymer-stabilized cholesteric liquid crystals. Various types of Ch-LCs are subsequently imbibed into the polymer template, resulting in films with distinct optical characteristics. Simultaneous red, green and blue reflection (multiple PBGs) and wide-band reflection in a single-layer Ch-LC film can be achieved by using nematic liquid crystals with different birefringence in Ch-LCs/polymer template composites, and a H-bonded Ch-LC with a great temperature-dependence of pitch length was introduced into the polymer template, and a temperature-tunable PBG of the Ch-LC film with a double-handed circularly polarized light reflection band was obtained. Additionally, the lasing emission of a single-layer Ch-LC film and patterning of a single-layer Ch-LC film with a double-handed circularly polarized light reflection band were also realized by the above approach. These special optical properties make the novel Ch-LCs composites interesting for their great potential applications in many fields, such as information recording, optical components, flat displays, photonic crystals etc. [ABSTRACT FROM AUTHOR]