The steady state and dynamic rheological properties of telechelic associative polymer solutions

In this study, steady state, dynamic shear and normal stress differences of the polymer solutions containing telechelic hydrophobically modified ethoxylated urethane (HEUR) associative polymers have been investigated. The intermediate steady state and dynamic shear thickening were observed for both ascending and descending shear rate and frequency, respectively. The dynamic amplitude stress sweep measurements showed that maxima in G′ and G″ occurred at the frequencies of 1, 5 and 10 rad/s. At lower shear rates and frequencies, the ratio of complex viscosity to steady shear viscosity was observed to be greater than unity. This phenomenon is believed to be associated with the formation of a micro-gel like structure. The modified Cox-Merz rule (Delaware-Rutgers rule) explained the dynamic and steady state viscosity behaviors well in the shear thinning zone but not at the plateau or shear thickening regions.