Structural rheology of composite onion phase

Abstract

We study the shear-induced composite onion phase formation behavior of the nonionic surfactant C10E3 lamellar phases containing colloidal particles. Composite lamellar phase gives rise to the onion phase similar to the free-particle system. Depending on the particle size and concentration, the nonlinear rheology and shear modulus are significantly influenced, while the critical shear rate and onion formation kinetics remains unchanged from those of the free-particle system. Modification of the nonlinear rheology indicates that the colloidal particles assist the onion structure formation so that undulation instability is easily induced by anchoring of membranes on surface of particles. The shear modulus of the composite lamellar and onion phases is reasonably explained by considering the line tension of defects and the effect of polyhedral edge of the onion, respectively.