viscoelasticity

Applied Physics Letters 99(8): 083701.

http://link.aip.org/link/doi/10.1063/1.3628456

Journal of Micromechanics and Microengineering

Volume 20, Number 9, 095016

http://dx.doi.org/10.1088/0960-1317/20/9/095016

Dielectric elastomer transducers are often subject to large tensile stretches and are susceptible to rupture. Here we carry out an experimental study of the rupture behavior of membranes of an acrylic dielectric elastomer (VHB 4905). Pure-shear test specimens are used to measure force-displacement curves, using samples with and without pre-cracks. We find that introducing a pre-crack into a membrane drastically reduces the stretch at rupture. Furthermore, we measure the stretch at rupture and fracture energy using samples of different heights at various stretch-rates. The stretch at rupture is found to decrease with sample height, and the fracture energy is found to increase with stretch-rate.
This paper has appeared in the Journal of Applied Physics and can be downloaded from:

A postdoctoral position is available immediately in Brinson’s Advanced Materials Lab involving collaborative work on finite element modeling of nanostructured polymer composites. The majority of the work will be split across two projects on the subject.  The first project involves 3D modeling of filled elastomers, with a focus on the viscoelastic properties. Non-linear viscoelastic modeling experience is a plus, but not required.

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 Abstract