Swelling kinetics of a compressed lamellar phase

We investigate how multilamellar vesicles prepared in a compressed state un der flow return to equilibrium. The kinetics is studied by following the te mporal evolution of the viscoelasticity after the shear is stopped. It exhi bits a two-step relaxation whose slower stage is strongly affected by tempe rature. According to a simple model, the temperature-dependent permeability of the lamellar phase is deduced from the measurements. We propose to attr ibute the permeability to handle-like defects, and its temperature dependen ce to all increase of the defect density when the lamellar-to-sponge phase transition is approached.