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ABSTRACT The conformation of a photoresponsive polymer bearing azo units in the main chain, poly(propionaldehyde azine) (PrAz), in tetrahydrofuran was investigated by viscosity measurements
before and after _trans_-to-_cis_ photoisomerization and also by the rotational isomeric state (RIS) model. Before photoisomerization (_i.e._, in the case of _trans_-pPrAz), viscosity data
indicated that pPrAz took a more extended conformation than did a diene polymer analog poly(butadiene). The RIS model analysis revealed that the extended conformation of pPrAz arose mainly
from the difficulty of gauche conformation around the carbon-carbon bond in the main chain. After _trans_-to-_cis_ photoisomerization (_i.e._, in the case of pPrAz consisting of _trans_ and
_cis_ units), viscosity data indicated that the photoisomerization led to a slight extension of the pPrAz chain. The RIS model analysis explained that the photoisomerization formed
preferentially the anti-_cis_ isomer, resulting in a larger characteristic ratio to avoid severe steric hindrance between the ethyl groups on neighboring main-chain carbon atoms. SIMILAR
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DILUTE SOLUTION Article 19 December 2023 ARTICLE PDF REFERENCES * For example: K. Kinbara and T. Aida, _Chem. Rev._, 105, 1377 (2005), and references therein. * For example: a) S. Yagai, T.
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were fixed at 0.65 and 0.35, respectively, upon calculation of _C_∞ for pPrAz after photoisomerization. Download references AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of
Macromolecular Science, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, 560-0043, Japan Akihito Hashidzume, Yusuke Ueno & Takahiro Sato Authors * Akihito
Hashidzume View author publications You can also search for this author inPubMed Google Scholar * Yusuke Ueno View author publications You can also search for this author inPubMed Google
Scholar * Takahiro Sato View author publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to Takahiro Sato. RIGHTS AND PERMISSIONS
Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Hashidzume, A., Ueno, Y. & Sato, T. Conformational Analysis of Poly(propionaldehyde azine) in Dilute Solution. _Polym J_ 38,
1152–1159 (2006). https://doi.org/10.1295/polymj.PJ2006066 Download citation * Received: 30 June 2006 * Accepted: 22 August 2006 * Published: 04 October 2006 * Issue Date: 01 November 2006
* DOI: https://doi.org/10.1295/polymj.PJ2006066 SHARE THIS ARTICLE Anyone you share the following link with will be able to read this content: Get shareable link Sorry, a shareable link is
not currently available for this article. Copy to clipboard Provided by the Springer Nature SharedIt content-sharing initiative KEYWORDS * Conformational Analysis * Characteristic Ratio *
Viscometry * Sedimentation Equilibrium * Poly(propionaldehyde azine) * Photoisomerization