Skip to main content
Log in

Liquid crystallinity of aqueous TEMPO-oxidized hydroxypropyl cellulose solutions: effects of main-chain and side-chain substituents

  • Original Research
  • Published:
Cellulose Aims and scope Submit manuscript

Abstract

Hydroxypropyl cellulose (HPC) is a stable molecule that presents cholesteric liquid crystal (ChLC) behavior in aqueous systems. However, this ChLC nature has not been fully utilized. In the present study, carboxy groups were introduced to HPC as a means to modify its aqueous ChLC characteristics. 2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO)-oxidation was performed for a HPC with degrees of substitution (DS) and molar substitution of the hydroxypropyl groups of 2.19 and 4.25, respectively. The oxidation reaction not only introduced carboxy groups to the C-6 position of the main chain, but also produced ketone groups by oxidizing the hydroxy groups at the side-chain termini. These ketone moieties could be reduced selectively under mild conditions. The degree of oxidation (DO; ≤ 0.37) and degree of ketone substitution (DSketone; ≤ 0.20) were determined by conductivity titration and NMR, respectively. The effects of substituents on the ChLC properties were determined by multiple regression analysis as well as empirical and theoretical analyses. An increase in DO decreased the twisting of the ChLC structure, while an increase in DSketone had little effect on twisting but increased the distance between polymer molecular chains and decreased the rigidity of the molecule as a whole. The interaction of the carboxy groups with the solvent water appeared to be shielded when the side-chain ends were ketonized. These findings provide information on the effects of backbone and side-chain substituents on the supramolecular structures of water-soluble ChLC as well as give the possibility of controlling ChLC via ionic functional groups.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

Download references

Acknowledgments

We thank Edanz (www.edanz.com/ac) for editing a draft of this manuscript.

Funding

This work was funded by Japan Society for the Promotion of Science, 21H02256, JST, JPMJMI18E3

Author information

Authors and Affiliations

Authors

Contributions

All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by SN and KM. The first draft of the manuscript was written by NS and YT and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Yoshikuni Teramoto.

Ethics declarations

Conflict of interest

The authors declare no conflicts of interest.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent for publication

All authors agreed to the publication in the submitted form.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary file1 (PDF 1625 KB)

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Nishida, S., Miyagi, K., Teramoto, Y. et al. Liquid crystallinity of aqueous TEMPO-oxidized hydroxypropyl cellulose solutions: effects of main-chain and side-chain substituents. Cellulose 30, 8665–8675 (2023). https://doi.org/10.1007/s10570-023-05427-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10570-023-05427-x

Keywords

Navigation