Synthesis and Thermal and Photoluminescence Properties of Liquid Crystalline Polyacetylenes Containing 4-Alkanyloxyphenyltrans-4-Alkylcyclohexanoate Side Groups

2002 ◽  
Vol 35 (4) ◽  
pp. 1180-1189 ◽  
Author(s):  
Ching-Hua Ting ◽  
Jiun-Tai Chen ◽  
Chain-Shu Hsu
Keyword(s):  
Liquid Crystalline ◽  
Photoluminescence Properties

Poly(pyridinium salt)s with organic counterions derived from an aromatic diamine containing oxyethylene unit exhibiting amphotropic liquid-crystalline and photoluminescence properties

Polymer ◽  
2009 ◽  
Vol 50 (14) ◽  
pp. 3128-3135 ◽  
Author(s):  
Pradip K. Bhowmik ◽  
Haesook Han ◽  
Alexi K. Nedeltchev ◽  
Hari D. Mandal ◽  
Jose A. Jimenez-Hernandez ◽  
...  
Keyword(s):  
Liquid Crystalline ◽  
Pyridinium Salt ◽  
Aromatic Diamine ◽  
Photoluminescence Properties ◽  
Oxyethylene Unit

scholarly journals Supramolecular liquid crystalline dendrimers with a porphyrin core and functional carboxylic acid dendrons

RSC Advances ◽  
2016 ◽  
Vol 6 (69) ◽  
pp. 65179-65185 ◽  
Author(s):  
Alberto Concellón ◽  
Madalina Bucoş ◽  
José Luis Serrano ◽  
Pilar Romero ◽  
Mercedes Marcos
Keyword(s):  
Carboxylic Acid ◽  
Self Assembly ◽  
Liquid Crystalline ◽  
Photoluminescence Properties ◽  
Smectic Mesophase ◽  
Supramolecular Dendrimers ◽  
Porphyrin Core ◽  
Liquid Crystalline Dendrimers

Supramolecular dendrimers prepared via H-bonding between porphyrin core and bifunctionalised dendrons, incorporated in the periphery, display photoluminescence properties and self-assembly into smectic mesophase.

Supramolecular structure of columnar liquid crystalline π-conjugated oligothiophenes with highly polarized photoluminescence properties

2009 ◽  
Vol 105 (11) ◽  
pp. 113513 ◽  
Author(s):  
Kiyoshi Minoura ◽  
Yusuke Akama ◽  
Jun Morita ◽  
Takuma Yasuda ◽  
Takashi Kato ◽  
...  
Keyword(s):  
Supramolecular Structure ◽  
Liquid Crystalline ◽  
Photoluminescence Properties

Freeze fracture imaging and computer simulation of liposome structure: Membrane geometry and defects

1983 ◽  
Vol 41 ◽  
pp. 646-647
Author(s):  
Joseph A. Zasadzinski
Keyword(s):  
Liquid Crystalline ◽  
Freeze Fracture ◽  
Continuum Theory ◽  
Closed Surfaces ◽  
Straight Line ◽  
Low Weight ◽  
Concentric Spheres ◽  
Membrane Geometry ◽  
Dupin Cyclides ◽  
Limiting Case

At low weight fractions, many surfactant and biological amphiphiles form dispersions of lamellar liquid crystalline liposomes in water. Amphiphile molecules tend to align themselves in parallel bilayers which are free to bend. Bilayers must form closed surfaces to separate hydrophobic and hydrophilic domains completely. Continuum theory of liquid crystals requires that the constant spacing of bilayer surfaces be maintained except at singularities of no more than line extent. Maxwell demonstrated that only two types of closed surfaces can satisfy this constraint: concentric spheres and Dupin cyclides. Dupin cyclides (Figure 1) are parallel closed surfaces which have a conjugate ellipse (r1) and hyperbola (r2) as singularities in the bilayer spacing. Any straight line drawn from a point on the ellipse to a point on the hyperbola is normal to every surface it intersects (broken lines in Figure 1). A simple example, and limiting case, is a family of concentric tori (Figure 1b).To distinguish between the allowable arrangements, freeze fracture TEM micrographs of representative biological (L-α phosphotidylcholine: L-α PC) and surfactant (sodium heptylnonyl benzenesulfonate: SHBS)liposomes are compared to mathematically derived sections of Dupin cyclides and concentric spheres.

Electron microscopy of crystalline structure in thermotropic random copolymers

1991 ◽  
Vol 49 ◽  
pp. 1054-1055
Author(s):  
Afzana Anwer ◽  
S. Eilidh Bedford ◽  
Richard J. Spontak ◽  
Alan H. Windle
Keyword(s):  
Electron Microscopy ◽  
Crystalline Structure ◽  
Liquid Crystalline ◽  
Elevated Temperatures ◽  
Random Copolymers ◽  
Molecular Characteristics ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Identical Monomer ◽  
Periodic Layer

Random copolyesters composed of wholly aromatic monomers such as p-oxybenzoate (B) and 2,6-oxynaphthoate (N) are known to exhibit liquid crystalline characteristics at elevated temperatures and over a broad composition range. Previous studies employing techniques such as X-ray diffractometry (XRD) and differential scanning calorimetry (DSC) have conclusively proven that these thermotropic copolymers can possess a significant crystalline fraction, depending on molecular characteristics and processing history, despite the fact that the copolymer chains possess random intramolecular sequencing. Consequently, the nature of the crystalline structure that develops when these materials are processed in their mesophases and subsequently annealed has recently received considerable attention. A model that has been consistent with all experimental observations involves the Non-Periodic Layer (NPL) crystallite, which occurs when identical monomer sequences enter into register between adjacent chains. The objective of this work is to employ electron microscopy to identify and characterize these crystallites.

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