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Title: Liquid crystalline epoxy networks with exchangeable disulfide bonds

Abstract

In this study, a liquid crystalline epoxy network (LCEN) with exchangeable disulfide bonds is synthesized by polymerizing a biphenyl-based epoxy monomer with an aliphatic dicarboxylic acid curing agent containing a disulfide bond. The effect of disulfide bonds on curing behavior and liquid crystalline (LC) phase formation of the LCEN is investigated. The presence of the disulfide bonds results in an increase in the reaction rate, leading to a reduction in liquid crystallinity of the LCEN. In order to promote LC phase formation and stabilize the self-assembled LC domains, a similar aliphatic dicarboxylic acid without the disulfide bond is used as a co-curing agent to reduce the amount of exchangeable disulfide bonds in the system. After optimizing the molar ratio of the two curing agents, the resulting LCEN exhibits improved reprocessability and recyclability because of the disulfide exchange reactions, while preserving LC properties, such as the reversible LC phase transition and macroscopic LC orientation, for shape memory applications.

Authors:
 [1];  [1]; ORCiD logo [2]; ORCiD logo [2]; ORCiD logo [3]
  1. Washington State Univ., Pullman, WA (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Washington State Univ., Pullman, WA (United States); North Dakota State Univ., Fargo, ND (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Advanced Manufacturing Office (EE-5A); USDOE Office of Science (SC)
OSTI Identifier:
1399941
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Soft Matter
Additional Journal Information:
Journal Volume: 13; Journal Issue: 29; Journal ID: ISSN 1744-683X
Publisher:
Royal Society of Chemistry
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Li, Yuzhan, Zhang, Yuehong, Rios, Orlando, Keum, Jong K., and Kessler, Michael R.. Liquid crystalline epoxy networks with exchangeable disulfide bonds. United States: N. p., 2017. Web. doi:10.1039/C7SM00934H.
Li, Yuzhan, Zhang, Yuehong, Rios, Orlando, Keum, Jong K., & Kessler, Michael R.. Liquid crystalline epoxy networks with exchangeable disulfide bonds. United States. doi:10.1039/C7SM00934H.
Li, Yuzhan, Zhang, Yuehong, Rios, Orlando, Keum, Jong K., and Kessler, Michael R.. 2017. "Liquid crystalline epoxy networks with exchangeable disulfide bonds". United States. doi:10.1039/C7SM00934H.
@article{osti_1399941,
title = {Liquid crystalline epoxy networks with exchangeable disulfide bonds},
author = {Li, Yuzhan and Zhang, Yuehong and Rios, Orlando and Keum, Jong K. and Kessler, Michael R.},
abstractNote = {In this study, a liquid crystalline epoxy network (LCEN) with exchangeable disulfide bonds is synthesized by polymerizing a biphenyl-based epoxy monomer with an aliphatic dicarboxylic acid curing agent containing a disulfide bond. The effect of disulfide bonds on curing behavior and liquid crystalline (LC) phase formation of the LCEN is investigated. The presence of the disulfide bonds results in an increase in the reaction rate, leading to a reduction in liquid crystallinity of the LCEN. In order to promote LC phase formation and stabilize the self-assembled LC domains, a similar aliphatic dicarboxylic acid without the disulfide bond is used as a co-curing agent to reduce the amount of exchangeable disulfide bonds in the system. After optimizing the molar ratio of the two curing agents, the resulting LCEN exhibits improved reprocessability and recyclability because of the disulfide exchange reactions, while preserving LC properties, such as the reversible LC phase transition and macroscopic LC orientation, for shape memory applications.},
doi = {10.1039/C7SM00934H},
journal = {Soft Matter},
number = 29,
volume = 13,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
Free Publicly Available Full Text
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