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arXiv · 1904.03250

Velocity jump in the crack propagation induced on a semi-crystalline polymer sheet by constant-speed stretching

Takako Tomizawa·Ko Okumura
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Abstract

It has long been known for elastomers that the velocity of crack propagation jumps as a function of strain. On the other hand, such a jump has not been reported in the literature for polymers which do not exhibit a rubbery plateau in the storage-modulus plot. Here, we report observation of jumps in crack propagation for semi-crystalline polymer sheets without the rubbery plateau, as a result of pulling the sheets at a constant speed. We discuss the advantages of this crack-propagation test under constant-speed stretching and provide physical interpretation of the velocity jump observed for non-elastomer sheets on the basis of a recently proposed theory for the velocity jump in crack propagation.

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Takako Tomizawa, Ko Okumura. 2019-04-05. Velocity jump in the crack propagation induced on a semi-crystalline polymer sheet by constant-speed stretching. https://doi.org/10.1016/j.polymer.2019.04.009

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