Composite stability and electro-optical properties enhanced by side-chain liquid crystal homopolymer “coating”

This study developed an effective method for improving the stability and electro-optic properties of carbon nanotubes (CNTs) and a 5CB composite liquid crystalline system, in which a side-chain liquid crystal homopolymer (SCLC) was used to coat CNTs. Polarising microscopy (POM) measurements indicate that SCLC ‘coating’ leads to a stable and uniform dispersion of CNTs in 5CB for over four days. Fourier‑transformed infrared spectroscopy (FTIR) characterisation suggests that there are likely conjugated interactions among SCLC, CNT, and 5CB, which results in the stable dispersion of SCLC-coated CNTs in 5CB. The compatible binding interaction of the three components also significantly affected the electro-optical properties of the composite system, including a reduced threshold voltage, shortened response time, an increased relaxation frequency value, and improved relevant dielectric properties. Theoretical calculations with first principles provided further insights into the interaction mechanisms among the three components, lending support to the idea that this polymer stabilised CNTs/5CB composite system may have great stability and bring considerably improved electro-optical properties. Our investigation illustrates that, by regulating the structure and content of the coated polymer, the performance of CNTs/5CB composites can be further optimised, providing a new strategy for solving the application bottleneck of liquid crystal display devices.