Chiroptical behavior of (acetyl)(ethyl)cellulose liquid crystalline solutions in chloroform

Jian Xin Guo, Derek G. Gray

Research output: Contribution to journalArticle

40 Citations (Scopus)

Abstract

Cholesteric liquid crystal solutions of (acetyl)(ethyl)cellulose (AEC) in chloroform exhibit an unusual optical property, changing from a left-handed to a right-handed helicoidal structure with increasing acetyl content. The change occurs at a critical degree of acetylation, DA, of around 0.18-0.20 for AEC solutions at room temperature. The acetyl content of AEC also strongly influences the magnitude of the cholesteric pitch and its temperature dependence. For acetyl contents below DA, the cholesteric solutions are left-handed, with pitches which increase with acetyl content and decrease on heating. For acetyl contents above DA, the solutions are right-handed, and the pitches decrease with increasing acetyl content and increase on heating. However, dilute solutions of all the AEC samples in chloroform show positive optical activity, independent of acetyl content.

Original languageEnglish (US)
Pages (from-to)2086-2090
Number of pages5
JournalMacromolecules
Volume22
Issue number5
StatePublished - May 1989
Externally publishedYes

Fingerprint

Chloroform
Chlorine compounds
Cellulose
Crystalline materials
Liquids
Cholesteric liquid crystals
Heating
Acetylation
Optical properties
ethyl cellulose
Temperature

ASJC Scopus subject areas

  • Materials Chemistry

Cite this

Chiroptical behavior of (acetyl)(ethyl)cellulose liquid crystalline solutions in chloroform. / Guo, Jian Xin; Gray, Derek G.

In: Macromolecules, Vol. 22, No. 5, 05.1989, p. 2086-2090.

Research output: Contribution to journalArticle

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