【摘 要】
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Vitrimer is a polymer network with dynamic covalent bonds,which can be dynamically broken and reformed.Thanks to the dynamic covalent bonds,vitrimer behaves like an elastomer at high deformation rate or low temperature but a viscous fluid at low deformati
【机 构】
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Department of Mechanical and Aerospace Engineering,University of California,San Diego,La Jolla,CA 92
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Vitrimer is a polymer network with dynamic covalent bonds,which can be dynamically broken and reformed.Thanks to the dynamic covalent bonds,vitrimer behaves like an elastomer at high deformation rate or low temperature but a viscous fluid at low deformation rate or high temperature.In this article,we study the cavitation dynamics in a vitrimer,which is known to be an important damaging mechanism in it.In the formulation,a nonlinear three-dimensional rate-dependent constitutive model for the vitrimer is adopted,in which both of the strain stiffening and the kinetics of dynamic exchanging reactions are considered.The theory predicts strong dependence of the cavitation dynamics on the loading rate.The computational results may help to reveal some critical insights into the rate-dependent fracture in vitrimer.
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