Effects of the functionality of epoxy monomer on the electro-optical properties of thermally-cured polymer dispersed liquid crystal films

Abstract

Polymer dispersed liquid crystal (PDLC) films were formed by thermal polymerisation-induced phase separation in epoxy monomer/polyamine/liquid crystal (LC) mixtures. The effects of the epoxy monomer functionality on the morphology of polymer network, electro-optical and peel strength of PDLC films were studied. As the functionality of epoxy monomer increased, the LC domain size of PDLC films decreased resulting in higher threshold voltage and saturation voltage, longer rise time, shorter decay time, meanwhile the peel strength of PDLC films enhanced.

Effect of Monomer Composition on the Performance of Polymer‐Stabilized Liquid Crystals with Two‐Step Photopolymerization

“…As we know, when the monomer has higher functionality and more active centers, its polymerization rate will be faster . The content of free‐radical polymerizable monomer C6M used in the experiment was 6%.…”

Effects of polymer network on electrically induced reflection band broadening of cholesteric liquid crystals

“…For the purpose of quantitative discussion, the SEM images of the polymer network was analyzed and the obtained averaged lateral size of fibrils of the polymer network are listed in Table . It is known that monomer functionality is a key factor in the formation of polymer networks, but the influences are complicated . Usually, higher functionality monomers can accelerate the polymerization reaction and increase the cross‐linking density since they have higher reactivity and more reactive sites.…”

Acrylate-assisted fractal nanostructured polymer dispersed liquid crystal droplet based vibrant colored smart-windows

“…In general, if the size of the LCs droplets is small, the higher V th is required to overcome stronger anchoring force, and if the droplet size is large, then the V th is lower. [41][42][43][44] When an intermediate voltage is applied, the LCs large droplets are aligned, but small droplets are not. The portion of the aligned droplets will be continuously changed depending on the voltage.…”

“…On the other hand, the long s OFF in both types of PDLCs may be ascribed to the polymer-LCs interface force. 44,45 No electric eld (E ¼ 0) was applied during the relaxation process, and the relaxation into disordered state was based on the surface anchoring process. 46 Because no energy was supplied and surface anchoring force was weaker than that from the external eld, the s OFF was longer than the s ON .…”