Dissipative properties and chain evolution of highly strained nanocomposite hydrogel
Autor: | Yongmao Pei, Jingda Tang, Youyi Sun, Daining Fang, Gao Xu |
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Rok vydání: | 2014 |
Předmět: | |
Zdroj: | Journal of Applied Physics. 116:244901 |
ISSN: | 1089-7550 0021-8979 |
Popis: | The dissipative property is crucial to the toughness and recovery of hydrogels. In our investigation, systematic uniaxial tension tests were conducted to evaluate the dissipative properties of poly (N-isopropylacrylamide) nanocomposite hydrogels. Two dissipative mechanisms are presented for both small and large stretches. Before yielding, most dissipation results from the orientation of clay platelets along the tensile direction; after yielding, polymer chains peel off from clay platelets to induce hysteresis. For the first time, a quadratic power law between the hysteresis work and the maximum stretch is obtained. The hysteresis work is irrelevant to the detailed loading history. When the hydrogel is unloaded to a critical displacement, polymer chains can re-adsorb to the surfaces of clay platelets. The quantity of re-ruptured physical bonds is proportional to the product of re-adsorption ratio and that of initially ruptured bonds. These results may be useful for the toughening design of hydrogels. |
Databáze: | OpenAIRE |
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