The influence of intramolecular hydrogen bonds on handedness in ethylcellulose /CH2Cl2 liquid crystalline mesophases

Tetsuo Kondo, Takeaki Miyamoto

Research output: Contribution to journalArticle

17 Citations (Scopus)

Abstract

This article shows that intramolecular hydrogen bonds formed at the three hydroxyl group positions of cellulosic glucose unit contribute in determining the handedness of chiral nematic mesophases ethylcellulose in CH2Cl2. Using two series of samples which differed only by increasing the ethyl substitution of the hydroxyl groups at either the C-6 or C-3 positions, the handedness of individual mesophase solutions was investigated using circular dichroism (CD). The CD spectra indicated that free hydroxyls at the C-6 position hindered dissolution in the solvent while hydroxyls at the C-3 position may play an important role in determining the handedness of the EC mesophase in CH2Cl2. Free hydroxyls at the C-3 position are known to easily form intramolecular hydrogen bonds, resulting in enhanced stiffness of the molecular chains. Therefore, these results lead to the conclusion that breaking intramolecular hydrogen bonds by increasing the substitution along the molecular chain causes it to become more flexible, which may account for the change in structural handedness.

Original languageEnglish
Pages (from-to)1123-1127
Number of pages5
Journalpolymer
Volume39
Issue number5
DOIs
Publication statusPublished - Jan 1 1998
Externally publishedYes

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Hydroxyl Radical
Hydrogen bonds
Dichroism
Crystalline materials
Liquids
Substitution reactions
Glucose
Dissolution
Stiffness
ethyl cellulose

All Science Journal Classification (ASJC) codes

  • Organic Chemistry
  • Polymers and Plastics

Cite this

The influence of intramolecular hydrogen bonds on handedness in ethylcellulose /CH2Cl2 liquid crystalline mesophases. / Kondo, Tetsuo; Miyamoto, Takeaki.

In: polymer, Vol. 39, No. 5, 01.01.1998, p. 1123-1127.

Research output: Contribution to journalArticle

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