ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Textures of the ethyl cellulose (EC)-dichloroacetic acid (DCA) mesomorphic solution were studied systematically by polarizing microscopy and small-angle light scattering. It was found that with increasing polymer concentration, the mesophase could show a disklike texture, an oil streak texture, a pseudoisotropic texture, and an iridescent planar texture. Within the mesophase the ordering degree is different in different zones. The phase transition between anisotropic and isotropic phases could also be accomplished by changing temperature. With increasing temperature the mesophase with the lower degree of order could first transform to the isotropic phase and the phase transition from an anisotropic phase with a higher degree of order to the isotropic one could take place only at the higher temperature. A disklike texture was also observed during the phase transition between the anisotropic and isotropic phases when the solution was heated and it was probably a basic texture in polymer cholesteric liquid crystals.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1991.070430912
