Preparation, characterization, and mesophase formation of esters of ethylcellulose and methylcellulose

Jian Xin Guo, D. G. Gray

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

A range of mixed ether‐esters of cellulose was prepared from partially substituted ethylcellulose and methylcellulose. The 13C‐NMR analysis of ethylcellulose with a DS of 2.5 indicated that the hydroxyl groups at carbon six of anhydroglucose units were completely substituted. Acetylation of the ethylcellulose under different conditions yielded (acetyl) (ethyl) cellulose (AEC) samples with acetyl degree of substitution ranging from 0 to 0.5. Fully substituted (propionyl) (ethyl) cellulose (PEC) and (acetyl) (methyl) cellulose (AMC) were also prepared. Chiral nematic liquid crystals were formed in these mixed ester/ethers of cellulose in concentrated solutions of acidic solvents. The critical concentration for the phase separation of the cellulosic solutions depended on the nature of the substituent, the degree of substitution, and the solvent at a given temperature. Methylcellulose solutions in trifluoroacetic acid and dichloroacetic acid form chiral nematic liquid crystals with a left‐handed helicoidal structure. The acetylated methyl cellulose samples did not show the reversal of handedness with increasing acetyl content that was previously observed for the corresponding ethylcellulose samples. © 1994 John Wiley & Sons, Inc.

Original languageEnglish (US)
Pages (from-to)889-896
Number of pages8
JournalJournal of Polymer Science Part A: Polymer Chemistry
Volume32
Issue number5
DOIs
StatePublished - Jan 1 1994
Externally publishedYes

Fingerprint

Methylcellulose
Cellulose
Esters
Nematic liquid crystals
Substitution reactions
Dichloroacetic Acid
Dichloroacetic acid
Trifluoroacetic acid
Trifluoroacetic Acid
Acetylation
Ethers
Phase separation
Hydroxyl Radical
ethyl cellulose
Carbon

Keywords

  • chiral‐nematic phases, handedness of
  • ethylcellulose, liquid crystalline esters of
  • methylcellulose, liquid crystalline esters of

ASJC Scopus subject areas

  • Polymers and Plastics
  • Organic Chemistry
  • Materials Chemistry

Cite this

Preparation, characterization, and mesophase formation of esters of ethylcellulose and methylcellulose. / Guo, Jian Xin; Gray, D. G.

In: Journal of Polymer Science Part A: Polymer Chemistry, Vol. 32, No. 5, 01.01.1994, p. 889-896.

Research output: Contribution to journalArticle

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