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The double cleavage drilled compression (DCDC) test has been introduced for glass but also extended to test polymer. It is a slender prismatic specimen with a hole in its middle and cracks that are initiated at both poles. It is interesting because the loading is uniaxial compression and the cracks are submitted to opening mode...

Polymers are viscoelastic and therefore are interesting for damping applications, especially when used at temperatures laying in their glassy-to-rubbery transition where the material is showing significant viscoelasticity. During his PhD co-advised by Gregoire Allaire, Samuel Amstutz and me, Antoni Joubert has worked on the shape optimization of thin structures such as beams and plates to...

Single-lap joint creep behaviour of two soft adhesives We have submitted two hot melt pressure sensitive adhesives (HMPSA) to bonded joint creep tests. While glassy state adhesives such as epoxys are often studied in the literature, data on soft adhesives that are in the rubbery state are scarce. These adhesives have applications such as sealing...

Five PEBAX foams provided by Arkema and obtained by mold-opening foam injection process has been studied. One one side, the microstructures have been characterized by DSC for the chemical and physical properties, and by scanning electron microscope image analysis for the structural properties. On the other side, the linear elasticity as well as the non-linear...

This is the python routine I used to calculate the linear viscoelasticity (storage and loss shear moduli) of worm-like microstructures define in the paper on linear viscoelasticity of IPNs. This routine may be used for any two-phase materials with the microstructure of your choice.You need two input.txt (phase1.txt and phase2.txt) files for the behavior constitutive...

The objective of the study was to characterize and model the linear viscoelasticity of interpenetrated polymer networks showing two clear distinct phase transitions. For this purpose we made in lab some acrylate IPNs by UV curing. In order to avoid fracture of the sample during the making process, the first single network is a lightly...

With industrial partner Arianegroup, we studied the mechanical behavior of three propellant-like materials. Two materials were made of an inert matrix with about 55% of sifted 250 microns ammonium perchlorate (AP) or RDX particles. The last material was the polymer matrix filled with about 20% of aluminium 3 microns particles and filled with AP fillers....

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...

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...

Why are we playing with rubber bouncing balls when we are kids ? Can metal or ‘plastic’ balls bounce as well ? And why do squash players warm up their balls before starting the game ? Let us have a little of recreation time bouncing balls and answer these questions. For that, some polymer balls are made in lab. The polymer is an...