An experimental study of the kinetically arrested states of colloidal suspensions

Abstract

The kinetically arrested states of soft materials such as colloidal and hydrogel suspensions are interesting because of their variable microstructures and heterogeneous and ultra slow dynamics. In this thesis, colloidal particles with tunable size polydispersities, sti nesses and activity have been synthesized and the approach to kinetic arrest of dense suspensions of these particles have been studied experimentally. Polydispersity, sti ness and activity are seen to greatly a ect the microstructures and dynamics of the arrested states of these dense suspensions. As the suspensions approach the kinetically arrested state, the growth of viscosity or relaxation times with volume fraction, the suspension fragility and the sizes of dynamical heterogeneities are strongly a ected by size polydispersity, sti ness and activity of the constituent colloidal particles. In this thesis, we have studied the structure, dynamics and flow behaviour of kinetically arrested states formed by thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) particles and in suspensions of active and passive colloidal particles