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Title: A study of poplar organosolv lignin after melt rheology treatment as carbon fiber precursors

Abstract

Lignins from various poplar genotypes were isolated by using organosolv fractionation and subjected to rheological treatment at various temperatures. Physicochemical characterization of the lignin variants shows a broad distribution of glass transition temperatures, melt viscosity, and pyrolysis char residues. Rheological treatment at 170 °C induces lignin repolymerization accompanied with an increase in condensed linkages, molecular weights, and viscosities. In contrast, rheology testing at 190 °C results in the decrease in lignin aliphatic and phenolic hydroxyl groups, β-O-aryl ether linkages, molecular weights, and viscosity values. Lignin under air cooling generates more oxygenated and condensed compounds, but lower amounts of ether linkages than lignin cooled under nitrogen. Here, lignin with a lower syringyl/guaiacyl ratio tends to form more cross-linkages along with higher viscosity values, higher molecular weight and larger amounts of condensed bonds.

Authors:
 [1];  [2];  [3];  [4];  [4];  [3];  [4];  [4];  [3];  [3];  [3];  [3];  [5]
  1. Georgia Institute of Technology, Atlanta, GA (United States); Univ. of Tennessee, Knoxville, TN (United States)
  2. Georgia Institute of Technology, Atlanta, GA (United States)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  4. Univ. of Tennessee Institute of Agriculture, Knoxville, TN (United States)
  5. Georgia Inst. of Technology, Atlanta, GA (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). BioEnergy Science Center (BESC)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1319236
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Green Chemistry
Additional Journal Information:
Journal Name: Green Chemistry; Journal ID: ISSN 1463-9262
Publisher:
Royal Society of Chemistry
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Sun, Qining, Khunsupat, Ratayakorn, Akato, Kokouvi, Tao, Jingming, Labbe, Nicole, Gallego, Nidia C., Bozell, Joseph J., Rials, Timothy G., Tuskan, Gerald A., Tschaplinski, Timothy J., Naskar, Amit K., Pu, Yunqiao, and Ragauskas, Arthur J.. A study of poplar organosolv lignin after melt rheology treatment as carbon fiber precursors. United States: N. p., 2016. Web. doi:10.1039/C6GC00977H.
Sun, Qining, Khunsupat, Ratayakorn, Akato, Kokouvi, Tao, Jingming, Labbe, Nicole, Gallego, Nidia C., Bozell, Joseph J., Rials, Timothy G., Tuskan, Gerald A., Tschaplinski, Timothy J., Naskar, Amit K., Pu, Yunqiao, & Ragauskas, Arthur J.. A study of poplar organosolv lignin after melt rheology treatment as carbon fiber precursors. United States. doi:10.1039/C6GC00977H.
Sun, Qining, Khunsupat, Ratayakorn, Akato, Kokouvi, Tao, Jingming, Labbe, Nicole, Gallego, Nidia C., Bozell, Joseph J., Rials, Timothy G., Tuskan, Gerald A., Tschaplinski, Timothy J., Naskar, Amit K., Pu, Yunqiao, and Ragauskas, Arthur J.. 2016. "A study of poplar organosolv lignin after melt rheology treatment as carbon fiber precursors". United States. doi:10.1039/C6GC00977H. https://www.osti.gov/servlets/purl/1319236.
@article{osti_1319236,
title = {A study of poplar organosolv lignin after melt rheology treatment as carbon fiber precursors},
author = {Sun, Qining and Khunsupat, Ratayakorn and Akato, Kokouvi and Tao, Jingming and Labbe, Nicole and Gallego, Nidia C. and Bozell, Joseph J. and Rials, Timothy G. and Tuskan, Gerald A. and Tschaplinski, Timothy J. and Naskar, Amit K. and Pu, Yunqiao and Ragauskas, Arthur J.},
abstractNote = {Lignins from various poplar genotypes were isolated by using organosolv fractionation and subjected to rheological treatment at various temperatures. Physicochemical characterization of the lignin variants shows a broad distribution of glass transition temperatures, melt viscosity, and pyrolysis char residues. Rheological treatment at 170 °C induces lignin repolymerization accompanied with an increase in condensed linkages, molecular weights, and viscosities. In contrast, rheology testing at 190 °C results in the decrease in lignin aliphatic and phenolic hydroxyl groups, β-O-aryl ether linkages, molecular weights, and viscosity values. Lignin under air cooling generates more oxygenated and condensed compounds, but lower amounts of ether linkages than lignin cooled under nitrogen. Here, lignin with a lower syringyl/guaiacyl ratio tends to form more cross-linkages along with higher viscosity values, higher molecular weight and larger amounts of condensed bonds.},
doi = {10.1039/C6GC00977H},
journal = {Green Chemistry},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 6
}

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Cited by: 4works
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