Viscosity Properties of the Colloidal Dispersions Co-Assembling By Peg with SDS

Viscosity properties of the mixing PEG-SDS solution was widely researched and mostly focused on the impact of SDS on the viscosity properties of aqueous PEG solution in the previous reports. Viscosity properties of the aqueous SDS solution affected by PEG are investigated by Ubbelohde viscometer in this paper to explore the structure of PEG-SDS colloidal dispersions. There is only a break point in the curves of relative viscosity (η_r) or reduced viscosity (η_sp/c_SDS) to concentration of SDS in the simple aqueous SDS solution at critical micelle concentration (cmc). By adding 2 g/L PEG into the aqueous SDS solution, η_r of the mixing PEG-SDS solution increases, and there occur  two break points in the curves of η_r-c_SDS or η_sp/c_SDS-c_SDS, which indicates that there is the interaction between SDS and PEG and form co-assembling colloidal dispersions. η_sp/c_SDS presents two extreme points at c₁ and c₂ and increases as c_SDS increases between c₁ and c₂, which is inferred resulting from SDS bound-micelles associated on PEG chains and resulting in a polyelectrolyte-like cluster structure.