CC BY-NC-ND 4.0 · Organic Materials 2020; 02(04): 313-322
DOI: 10.1055/s-0040-1721052
Focus Issue: Structure to Function in Supramolecular Polymers and Materials
Original Article

Mechanoresponsive Elastomers Made with Excimer-Forming Telechelics

a   Adolphe Merkle Institute (AMI), Polymer Chemistry and Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
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a   Adolphe Merkle Institute (AMI), Polymer Chemistry and Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
b   Key Laboratory of Organic Optoelectronics and Molecular Engineering, Department of Chemistry, Tsinghua University, Mengminweikeji Building South Building, Beijing 100084, China
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a   Adolphe Merkle Institute (AMI), Polymer Chemistry and Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
c   Pritzker School of Molecular Engineering, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, United States
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a   Adolphe Merkle Institute (AMI), Polymer Chemistry and Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
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a   Adolphe Merkle Institute (AMI), Polymer Chemistry and Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
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a   Adolphe Merkle Institute (AMI), Polymer Chemistry and Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
› Institutsangaben
Funding Information The authors gratefully acknowledge financial support through the National Center of Competence in Research (NCCR) Bio-Inspired Materials, a research instrument of the Swiss National Science Foundation (SNF), as well as funding from the Adolphe Merkle Foundation.


Abstract

Mechanoresponsive luminescent (MRL) elastomers, which change their fluorescence color or intensity upon deformation, can facilitate simple strain detection through optical signals. Several polymers have been endowed with MRL properties by blending them with excimer-forming dyes, whose assembly and emission color are affected by deformation of the blended materials. However, access to elastic MRL polyurethanes based on this approach has proven difficult and usually requires the covalent incorporation of such dyes in high concentration. Here, we show that much simpler access to MRL elastomers is possible by blending thermoplastic polyurethane elastomers with a small weight fraction of a telechelic sensor macromolecule carrying two excimer-forming oligo(p-phenylene vinylene) dyes at the termini. While the mechanical properties of the two polyurethanes, which were selected because of their dissimilar mechanical behaviors, remain unchanged, the additive imparts these materials with MRL characteristics. Notably, the reliable and reversible detection of strains as low as 5% is possible. The highly sensitive mechanochromic response mirrors the deformation and relaxation processes occurring in these model polyurethanes and enabled a detailed analysis of the processes underlying the shape-memory properties in one of the polyurethanes, in which such behavior was imparted by a crystallizable soft segment.

Supporting Information

Supporting information for this article is available online at https://doi.org/10.1055/s-0040-1721052.


Supporting Information

Primary Data



Publikationsverlauf

Eingereicht: 28. August 2020

Angenommen: 07. Oktober 2020

Artikel online veröffentlicht:
08. Dezember 2020

© 2020. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

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