NMR study of liquid crystalline polymer curing in magnetic field

1997 ◽  
Vol 12 (4) ◽  
pp. 581-588
Author(s):  
L. L. Gur’eva ◽  
V. P. Tarasov ◽  
K. V. Ermolaev ◽  
L. N. Erofeev ◽  
B. A. Rozenberg
Keyword(s):  
Magnetic Field ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer ◽  
Nmr Study ◽  
Polymer Curing

Deuteron NMR study of molecular order and motion in a liquid crystalline polymer

1982 ◽  
Vol 104 (3) ◽  
pp. 917-919 ◽  
Author(s):  
H. Geib ◽  
B. Hisgen ◽  
U. Pschorn ◽  
H. Ringsdorf ◽  
H. W. Spiess
Keyword(s):  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer ◽  
Molecular Order ◽  
Nmr Study ◽  
Deuteron Nmr

Elastic deformations in a magnetic field of a liquid-crystalline polymer with mesogenic groups in the main and side chains

1994 ◽  
Vol 30 (12) ◽  
pp. 1461-1465 ◽  
Author(s):  
L.N. Andreeva ◽  
A.P. Filippov ◽  
V.N. Tsvetkov ◽  
V.V. Zuev ◽  
S.S. Skorokhodov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer ◽  
Side Chains ◽  
Elastic Deformations

Liquid Crystalline Polymer–Co Nanorod Hybrids: Structural Analysis and Response to a Magnetic Field

2014 ◽  
Vol 118 (11) ◽  
pp. 3218-3225 ◽  
Author(s):  
Ophélie Riou ◽  
Barbara Lonetti ◽  
Patrick Davidson ◽  
Reasmey P. Tan ◽  
Benoit Cormary ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Structural Analysis ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer

Orientation of nematic liquid crystalline polymer in a magnetic field. Evaluation of magnetic susceptibility

Polymer ◽  
1981 ◽  
Vol 22 (5) ◽  
pp. 578-580 ◽  
Author(s):  
C Noel ◽  
L Monnerie ◽  
M.F Achard ◽  
F Hardouin ◽  
G Sigaud ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Susceptibility ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer ◽  
Field Evaluation

Defect Dynamics of a Nematic Polymer in a Magnetic Field

1990 ◽  
Vol 209 ◽  
Author(s):  
Alejandro D. Rey
Keyword(s):  
Magnetic Field ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Numerical Solutions ◽  
Crystalline Polymer ◽  
Dynamical Response ◽  
Nonlinear Dynamical ◽  
Disclination Line ◽  
Initial Polymer ◽  
Nematic Polymer

ABSTRACTAnalysis of the nonlinear dynamical response of a rod-like nematic liquid crystalline polymer, between parallel untreate plates, in a magnetic field is presented. Numerical solutions to the torque balance equations showthat when a uniformly aligned polymer is acted by a magnetic field normal to the initial polymer orientation an array of inversion walls develops. Stability analysis shows that the inversion walls are unstable to localized perturbations. The nonlinear resolution ofthe instability leads to the nucleation of an array of disclination line pairs of strength ±1/2. A perturbation analysis is used to obtain the evolution of the polymer structure towards equilibrium

Observing the relaxation of molecular orientation in sheared liquid crystalline polymer solutions

1990 ◽  
Vol 48 (4) ◽  
pp. 1092-1093
Author(s):  
Wendy Putnam ◽  
Christopher Viney
Keyword(s):  
Molecular Orientation ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer ◽  
Polymer Processing ◽  
Molecular Alignment ◽  
Global Alignment ◽  
Shear Direction ◽  
Axial Strength ◽  
Strength And Stiffness

Liquid crystalline polymers (solutions or melts) can be spun into fibers and films that have a higher axial strength and stiffness than conventionally processed polymers. These superior properties are due to the spontaneous molecular extension and alignment that is characteristic of liquid crystalline phases. Much of the effort in processing conventional polymers goes into extending and aligning the chains, while, in liquid crystalline polymer processing, the primary microstructural rearrangement involves converting local molecular alignment into global molecular alignment. Unfortunately, the global alignment introduced by processing relaxes quickly upon cessation of shear, and the molecular orientation develops a periodic misalignment relative to the shear direction. The axial strength and stiffness are reduced by this relaxation.Clearly there is a need to solidify the liquid crystalline state (i.e. remove heat or solvent) before significant relaxation occurs. Several researchers have observed this relaxation, mainly in solutions of hydroxypropyl cellulose (HPC) because they are lyotropic under ambient conditions.

Sign in / Sign up

Export Citation Format

Share Document