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International audienceThe visco elastic behavior of graphite oxide-loaded PDMS suspensions showed, at low frequencies, a dominant elastic behavior with the appearance of a secondary plateau above 1.5 wt %. Within the investigated concentrations, such behavior was not observed for the graphite and functionalized graphite oxide/PDMS suspensions. This low percolation threshold of GO sheets was attributed to a macroscale aggregation. Furthermore, the critical strain (transition between the linear and nonlinear regime) was observed to slightly s. depend on the particle concentration (gamma(c) proportional to phi(-1 +/- 0.2)) Consequently, the exponent x (x = 0.4), related to the filler volume fraction and the aggregate structure, is lower than 1. This result means that a fractal structure cannot be associated with the aggregation of GO sheets. Actually, GO sheets aggregate into agglomerates that span through the gap between the plates of the rheometer. Agglomeration of GO sheets without any fractal structure explains this particular behavior. Furthermore, recovery tests consisting of subsequent strain sweep tests proved that the initial equilibrium network can be totally and rapidly restored. This particular behavior originates from the low viscosity of the PDMS suspension allowing Brownian motion of graphene oxide sheets to occur within only a few seconds

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