Title data
Posada Murcia, Andrés ; Uribe Gómez, Juan Manuel ; Förster, Stephan ; Sommer, Jens-Uwe ; Dulle, Martin ; Ionov, Leonid:
Mechanism of Behavior of Two-Way Shape Memory Polymer under Constant Strain Conditions.
In: Macromolecules.
Vol. 55
(2022)
Issue 5
.
- pp. 1680-1689.
ISSN 1520-5835
DOI: https://doi.org/10.1021/acs.macromol.1c02564
Project information
Project financing: |
Deutsche Forschungsgemeinschaft IO 68/10-1 IO 68/11-1 SO 277/18-1 |
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Abstract in another language
In this paper, we report detailed investigation of structural changes occurring in two-way shape memory polymers (2W-SMP) upon thermal cycling at constant strain conditions. We demonstrate that cooling of stretched chemically cross-linked polycaprolactone results first in a slow decrease of stress, the stress drops rapidly upon further cooling, and further cooling results in sharp increase of stress. In this paper, we investigated structural changes occurring in each of these three phases using in situ force measurements and XRD analysis (SAXS and WAXS). In the first phase, the stress decreases due to decrease of entropic factor in the elastic state. In the second phase, polymer chains start to crystallize in the stretched state as a result of the number of active springs producing stress decreasing. This results in the decrease of the stretching degree of other polymer chains, and finally, unstretched polymer chains crystallize that result in an increase of stress─the polymer simply tends to shrink.
Further data
Item Type: | Article in a journal |
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Refereed: | No |
Institutions of the University: | Faculties > Faculty of Engineering Science > Professor Biofabrication > Professor Biofabrication - Univ.-Prof. Dr. Leonid Ionov Faculties Faculties > Faculty of Engineering Science Faculties > Faculty of Engineering Science > Professor Biofabrication |
Result of work at the UBT: | Yes |
DDC Subjects: | 500 Science > 530 Physics 500 Science > 540 Chemistry 600 Technology, medicine, applied sciences > 660 Chemical engineering |
Date Deposited: | 16 Feb 2022 08:00 |
Last Modified: | 27 Jul 2023 12:45 |
URI: | https://eref.uni-bayreuth.de/id/eprint/68685 |