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Anti-fatigue-fracture hydrogels.

ABSTRACT: The emerging applications of hydrogels in devices and machines require hydrogels to maintain robustness under cyclic mechanical loads. Whereas hydrogels have been made tough to resist fracture under a single cycle of mechanical load, these toughened gels still suffer from fatigue fracture under multiple cycles of loads. The reported fatigue threshold for synthetic hydrogels is on the order of 1 to 100 J/m². We propose that designing anti-fatigue-fracture hydrogels requires making the fatigue crack encounter and fracture objects with energies per unit area much higher than that for fracturing a single layer of polymer chains. We demonstrate that the controlled introduction of crystallinity in hydrogels can substantially enhance their anti-fatigue-fracture properties. The fatigue threshold of polyvinyl alcohol (PVA) with a crystallinity of 18.9 weight % in the swollen state can exceed 1000 J/m².

SUBMITTER: Lin S

PROVIDER: S-EPMC6357728 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Anti-fatigue-fracture hydrogels.

Lin Shaoting S Liu Xinyue X Liu Ji J Yuk Hyunwoo H Loh Hyun-Chae HC Parada German A GA Settens Charles C Song Jake J Masic Admir A McKinley Gareth H GH Zhao Xuanhe X

Science advances 20190125 1

The emerging applications of hydrogels in devices and machines require hydrogels to maintain robustness under cyclic mechanical loads. Whereas hydrogels have been made tough to resist fracture under a single cycle of mechanical load, these toughened gels still suffer from fatigue fracture under multiple cycles of loads. The reported fatigue threshold for synthetic hydrogels is on the order of 1 to 100 J/m<sup>2</sup>. We propose that designing anti-fatigue-fracture hydrogels requires making the ...[more]

PMID: 30746464

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