scholarly journals Prediction and Design of First Super-Strong Mostly-Rigid Polymers from Very Molecular Theories for Smectic and Nematic Polymers

1988 ◽  
Vol 134 ◽  
Author(s):  
F. Dowell
Keyword(s):  
Liquid Crystalline ◽  
Ad Hoc ◽  
Liquid Crystalline Polymers ◽  
Side Chain ◽  
Crystalline Polymers ◽  
Smectic A ◽  
Molecular Ordering ◽  
Nematic Polymers ◽  
Experimental Values ◽  
Atom Bond

ABSTRACTThis paper presents a unique microscopic molecular theory for backbone liquid-crystalline polymers (LCPs), side-chain LCPs, and combined LCPs in the nematic (N) and multiple smectic-A (SA) LC phases and the isotropic (I) liquid phase. There are no ad hoc or arbitrarily adjustable parameters in this theory. The agreement between the theoretical and experimental values for various thermodynamic and molecular ordering properties for existing LCPs is very good (relative deviations between 0% and less than 6.2%). This theory has been used by this author to predict and design (atom by atom, bond by bond) the first super-strong (SS) LCPs. This paper presents the design of SS mostly-rigid (MR) LCPs.

Synthesis of Ferroelectric Liquid Crystalline Polymers by Ring Opening Polymerization

1996 ◽  
Vol 425 ◽  
Author(s):  
C. S. Hsu ◽  
C. J. Lee
Keyword(s):  
Ring Opening ◽  
Liquid Crystalline ◽  
Liquid Crystalline Polymers ◽  
Ring Opening Polymerization ◽  
Side Chain ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Crystalline Polymers ◽  
Smectic A ◽  
Smectic C

AbstractThe synthesis of two series of side-chain liquid crystalline polyoxetanes and polyoxiranes containing 4-alkanyloxybiphenyl-4′ -yl (2S,3S)-2-chloro-3-methylvalerate side groups is presented. Differential scanning calorimetry, polarizing optical microscopy, and X-ray diffractometry reveal smectic mesomorphism for all obtained polymers. Most of the prepared polyoxetanes present smectic A and chiral smectic C phases. The polyoxetane containing tweleve methylene units in the spacer is the only one showing two enantiotropic smectic A and B phases. All of the obtained polyoxiranes display two enantiotropic smectic A and B phases. Although the polyoxetane and polyoxirane backbones are more flexible than the polymethacrylate backbone, side-chain crystallization do not occur in any of the synthesized polymers.

scholarly journals Theoretical Predictions for Side-Chain Liquid-Crystal Polymers and Comparison to Experiment

1988 ◽  
Vol 134 ◽  
Author(s):  
F. Dowell
Keyword(s):  
Liquid Crystalline ◽  
Ad Hoc ◽  
Side Chain ◽  
Liquid Crystal Polymers ◽  
Side Chains ◽  
Crystalline Polymers ◽  
Theoretical Predictions ◽  
Experimental Values ◽  
First Time ◽  
Theoretical Results

ABSTRACTThis paper presents results from a unique microscopic molecular theory for side-chain liquid-crystalline polymers (LCPs) in the nematic (N) and multiple smectic-A (SA) LC phases and the isotropic (I) liquid phase. There are no ad hoc or arbitrarily adjustable parameters in this theory. The agreement between the theoretical and experimental values for various properties (including transition temperatures and quadratic characteristic radii) is very good (relative deviations between 0% and less than 6.2%). The theoretical results also show--for the first time--that the N and I phases for these LCPs involve the packing of plate-like sections of backbones and side chains and that the local bilayer SA phase involves packing of side-chains within a plate-like section. This type of packing is predicted to be typical for side-chain LCPs. This theory can predict-- for the first time--whether the side chains of a molecule pack on the same or alternating opposite sides of the backbone and whether side chains on different molecules interdigitate (overlap) with each other.

scholarly journals Phase Transitions of Side Chain Liquid Crystalline Polymers Having a Terminal Alkyl Chain.

1993 ◽  
Vol 50 (9) ◽  
pp. 687-691 ◽  
Author(s):  
Seiji UJIIE ◽  
Tamami FUKUI ◽  
Kazuko HIGAKI ◽  
Satoshi TAKAHASHI ◽  
Kazuyoshi IIMURA
Keyword(s):  
Phase Transitions ◽  
Liquid Crystalline ◽  
Alkyl Chain ◽  
Liquid Crystalline Polymers ◽  
Side Chain ◽  
Crystalline Polymers
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