Chiral nematic suspensions of cellulose crystallites; phase separation and magnetic field orientation

作者：Jean‐François Revol, Louis Godbout, Xue-Min Dong, Derek G. Gray, Henri Chanzy, Georg U Maret · 发表于：Liquid Crystals · 年份：1994 · DOI：10.1080/02678299408036525 · 被引用次数：462 · 研究领域：Liquid Crystal Research Advancements、Advanced Cellulose Research Studies、Advanced Materials and Mechanics

Suspensions of rod-like cellulose crystallites of axial ratio ≈ 20–40, prepared by acid hydrolysis of natural cellulose fibres with sulphuric acid, give stable ordered fluids that display well-formed textures and disclinations characteristic of chiral nematic liquid crystalline phases. The critical volume fraction for phase separation of salt-free suspensions is typically 0.03, with a relatively narrow biphasic region. Because of the negative diamagnetic susceptibility of cellulose, the ordered phase becomes oriented in a magnetic field with its chiral nematic axis parallel to the applied field.