On necessary precautions when measuring solid polymer linear viscoelasticity with torsion rheometers

The linear viscoelasticity and time-temperature superposition of solid polymers are often characterized using a torsion rheometer since it is a common equipment in polymer labs. Specimen are submitted to a dynamic torsion angle while the resulting torque is recorded. The torsion test gives access to the storage and loss shear moduli. When rectangular slender specimen […]

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Fracture of carbon-black filled elastomers submitted to monotonous loadings

We are currently interested in the catastrophic failure of carbon-black filled and unfilled elastomers submitted to monotonous loadings (not fatigue). First part of this work is to establish a clear criterion for mode I catastrophic fracture when it happens. For this purpose, single edge notch tension tests were run on three different materials, an unfilled styrene […]

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Shape memory property of amorphous polymer networks. Experimental characterization (2)

In a previous post, I have presented some of our results obtained during stress-free shape memory recovery of amorphous polymer networks submitted to large deformation torsion tests. These tests introduce large deformation but moderate strain. In order to provide a rather complete set of data on the strain recovery and `stress recovery’ for amorphous polymers, including large strain, uniaxial […]

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Shape memory property of amorphous polymer networks. Mechanical model

  The shape memory property of amorphous polymer networks is the result of two intrinsic properties of these materials: 1) The viscoelasticity and 2) the time-temperature superposition property. This can be proven by characterizing the material linear viscoelasticity and time-temperature superposition with DMA (dynamic mechanical analysis) tests and by introducing these properties in a TRS (thermo-theologically […]

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Linear viscoelasticity of several carbon-black SBRs

The linear viscoelasticity of several carbon-black filled SBRs were characterized by DMA tests on a DMAQ800 dynamic uniaxial tension machine from TA. Figure 1. Storage modulus and damping factor of several carbon-black filled SBRs measured by uniaxial tension DMA tests. Materials are made of the same gum and filled with 0, 5, 30, 40, 50 […]

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ACS Rubber division Sparks Thomas Award 2015

  I was awarded by the Rubber division of the American Chemistry Society of the Sparks-Thomas award. Got it just it time before it was too late since I graduated from high school in 1990 and the award demand that the researcher passed its baccalaureate less than 25 years ago. The work I accomplished in […]

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