Scanning Electron Microscopy (SEM) picture of (a) PVC used for D1 and (b) PVC used for D2. Scale bar at the bottom right of each picture is 1 µm. 

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... focus on two dispersions of PVC particles. SEM pictures of particles are displayed in Fig. 2 while particle size distributions in Dinch are displayed in Fig. 3. In the first dispersion (D1), the mean particle radius, defined as R 32 =< R 3 > / < R 2 > is 1 µm. The size distribution is lognormal and the standard deviation esti- mated using the volume distribution is 45%. In the second disper- sion (D2), the particle size histogram using a volume distribution is bimodal with lognormal peaks around 350 nm (standard de- viation of 25%) and 3.3 µm (standard deviation of 55%). cle radius) in the range of 10-10 6 for which Brownian effects are practically negligible 27 . The random close packing fractions φ RCP of these dispersions are measured. φ RCP corresponds to the value of the solid frac- tion at which the viscosity diverges at low shear rate under the hypothesis of frictionless particles 6,8 . We measure the value of the viscosity at ˙ γ = 10s −1 to get rid of interparticle interac- tions at low shear rate 28 . The data are fitted using a Krieger- Dougherty model η = η s (1 − φ φ RCP ) −n , where η s is the solvent viscosity. We get φ RCP = 69.4% ± 0.25% for D1 suspensions and φ RCP = 77.2% ± 0.25% for D2. The exponents n of the Krieger- Dougherty models are respectively n = 2.3 for the D1 dispersion and n = 2.9 for the D2 dispersion. η s is equal to 41 ...