Polymer-dispersed Liquid Crystals (polymer-dispersed + liquid_crystal)

Distribution by Scientific Domains


Selected Abstracts


Electrochromic Polymer-Dispersed Liquid-Crystal Film: A New Bifunctional Device,

ADVANCED FUNCTIONAL MATERIALS, Issue 6 2005
P. Nicoletta
Abstract Polymer-dispersed liquid crystals (PDLCs) are liquid-crystal dispersions within a polymer matrix. These films can be changed from an opaque to a transparent state by applying a suitable alternating-current electric field. PDLCs have attracted the interest of researchers for their applications as light shutters, smart windows, and active displays. For such applications, electrochromic devices, which change color as a result of electrochemical reactions, have also become a recent focus of research. Herein, we report our preliminary results on bifunctional devices based on PDLCs that host electrochromic guest molecules. Such devices allow both an independent and fast switching from a scattering opaque state to a transmissive transparent state owing to liquid-crystal reorientation and a color change from white (pale yellow) to dark blue, due to either oxidation or reduction of the electrochromic molecules. [source]


Application and New Developments in Polymer-Dispersed Liquid Crystal Simulation Studies

MACROMOLECULAR THEORY AND SIMULATIONS, Issue 7 2007
Young Jae Jeon
Abstract Polymer-dispersed liquid crystals (PDLCs) represent an important new class of materials with electro-optic applications such as flexible displays, large-area devices projection displays, electrically switchable windows, etc. On considering such applications of these materials, many studies have been performed on the experimental side. Similarly, research on the simulation side for the PDLCs is of the fundamental interest too. The present article contains a short review on the present and past simulation studies of PDLCs. Various molecular simulation approaches applied to PDLC systems by different groups are reviewed here. In addition some new findings of the bulk phases are also extensively described. [source]


Nanosized-Silica-Reinforced Holographic Polymer-Dispersed Liquid Crystals

MACROMOLECULAR RAPID COMMUNICATIONS, Issue 7 2006
Eun Hee Kim
Abstract Summary: Nanosized silicas added to holographic polymer-dispersed liquid crystals (HPDLC) provide the resin phase with increased elasticity, dimensional stability, and the high diffraction efficiency of the gratings. On the other hand, nucleation and growth of periodic modulation are delayed, especially with small-sized silica because of the increased viscosity of the resin mixture. Effects of the LC/resin composition and cell gap on the diffraction efficiency have also been studied. AFM image of silica added HPDLC. [source]


Fabricating three-dimensional polymeric photonic structures by multi-beam interference lithography,

POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 2 2006
Jun Hyuk Moon
Abstract The fabrication of true three-dimensional (3D) microstructures both rapidly and economically over a large area with negligible defects is attractive for a wide range of applications. In particular, multi-beam interference lithography is one of the promising techniques that can mass-produce polymeric 3D photonic crystals defect-free over a large area. This review discusses the relationship between beam geometry and the symmetry of the interference patterns, the lithographic process, and various types of photoresist systems, including thick films of negative-tone and positive-tone photoresists, organic-inorganic hybrids, hydrogels, and holographic polymer-dispersed liquid crystals. Copyright 2006 John Wiley & Sons, Ltd. [source]