title: Phases and structures of sunset yellow and disodium cromoglycate mixtures in water.
abstract: We study phases and structures of mixtures of two representative chromonic liquid crystal materials, sunset yellow FCF (SSY) and disodium cromoglycate (DSCG), in water. A variety of combinations of isotropic, nematic (N), and columnar (also called M) phases are observed depending on their concentrations, and a phase diagram is made. We find a tendency for DSCG-rich regions to show higher-order phases while SSY-rich regions show lower-order ones. We observe uniform mesophases only when one of the materials is sparse in the N phases. Their miscibility in M phases is so low that essentially complete phase separation occurs. X-ray scattering and spectroscopy studies confirm that SSY and DSCG molecules do not mix when they form chromonic aggregates and neither do their aggregates when they form M phases.
authors: Soft Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA.
authors: Akihiro
authors: A
authors: Yamaguchi
authors: Soft Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA.
authors: Gregory P
authors: GP
authors: Smith
authors: Soft Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA.
authors: Youngwoo
authors: Y
authors: Yi
authors: Fairview High School, Boulder, Colorado 80305, USA.
authors: Charles
authors: C
authors: Xu
authors: Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, Italy.
authors: Silvia
authors: S
authors: Biffi
authors: Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, Italy.
authors: Francesca
authors: F
authors: Serra
authors: Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, Italy.
authors: Tommaso
authors: T
authors: Bellini
authors: Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors: Chenhui
authors: C
authors: Zhu
authors: Soft Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA.
authors: Noel A
authors: NA
authors: Clark
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D004205:Cromolyn Sodium / Q000737:chemistry*; D050866:Liquid Crystals / Q000737:chemistry*; D008853:Microscopy; D015394:Molecular Structure; D044367:Phase Transition; D013057:Spectrum Analysis; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D001391:Azo Compounds; D014867:Water; C005842:6-hydroxy-5-((p- sulfophenyl)azo)-2-naphthalenesulfonic acid disodium salt; D004205:Cromolyn Sodium