open access

https://hdl.handle.net/2115/94098

Effect of Predamage on the Fracture Energy of Double-Network Hydrogels

英語

2024-02-20

American Chemical Society

ACS macro letters

13(2)

130-137

Double-network (DN) hydrogels are tough soft materials, and the high fracture resistance can be attributed to the formation of a large damage zone (internal fracture of the brittle first network) around the crack tip. In this work, we studied the effect of predamage in the brittle network on the fracture energy Gamma(c) of DN hydrogels. The prestretch of the first network was induced by prestretching the DN gels to prestretch ratio lambda(pre). Depending on the lambda(pre) in relative to the yielding stretch ratio lambda(y), above which the brittle first network starts to break into discontinuous fragments inside DN gels, two regimes were observed: Gamma(c) decreases monotonically with lambda(pre) in the regime of lambda(pre) < lambda(y), mainly due to the decreasing contribution from the bulk internal damage, while Gamma(c) increases with lambda(pre) in the regime of lambda(pre) > lambda(y). The latter can be understood by the release of the hidden length of the stretchable network strands by the rupture of the brittle network, whereby the broken fragments of the brittle network could serve as sliding cross-links to further delocalize the stress-concentration near the crack tip and prevent chain scissions.

学術雑誌論文

Accepted Manuscript

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS macro letters, copyright c American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/articlesonrequest/AOR-9HVR9WTGNNQYQQRWFXKA