Bond strength regime dictates stress relaxation behavior.
Soft Matter
; 18(26): 4937-4943, 2022 Jul 06.
Article
em En
| MEDLINE
| ID: mdl-35730637
ABSTRACT
Reconfigurable polymer networks are gaining interest for their potential applications as self-healing, recyclable, and stimuli-responsive smart materials. Relating the bond strength of dynamic interactions to material properties including stress relaxation time and modulus is crucial for smart material design. In this work, in situ crosslinked transition metal-terpyridine reconfigurable networks were utilized to modulate the characteristic network stress relaxation time, τR. The use of stress relaxation experiments rather than oscillatory frequency sweeps allowed for the measurement of network bond dynamics across a wider dynamic range than has been previously reported. The stress relaxation time was shown to be tunable by metal center, counterion, and crosslink density. Remarkably, the network crosslinked with covalent-like ruthenium chloride-terpyridine interaction, while having a longer τR, was qualitatively similar to the other metal-ligand networks. Furthermore, the relaxation time was independent of crosslink density in strongly bonded networks, allowing for independent tunability of modulus and τR. In contrast, increasing crosslink density reduced τR in networks crosslinked with weaker interactions.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Soft Matter
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Estados Unidos