Polymer-stabilized cholesteric liquid crystal using polyurethane acrylate

Polymer-stabilized cholesteric liquid crystals (PSCLCs) have been designed and fabricated with various polymers (polyurethane acrylate contents and polymer functionalities), which were controlled by using the oligomer molecular weight and the reactive diluent content. It was possible to control the reflectivity by changing these variables, giving a maximum reflection efficiency (488 nm) of over 50 % with PPG 500 at 90 % LC without an alignment layer. It was possible to fabricate PSCLCs having a reflectivity and a pitch. that virtually did not change as polymer was added, regardless of the polymer content. The morphology and the color purity were visualized by using scanning electron microscopy and polarized optical microscopy image, respectively.