Hydrophobically modified polymers are composed of water soluble and water insoluble (hydrophobic alkyl end groups) components. They are referred to as associative polymers since their aqueous solutions exhibit enhanced viscosities due to the aggregation of their alkyl end groups into micelle-like structures. The aggregation is attributed to the rejection of the hydrophobic end groups by the water. The rheological properties including the creep recovery behavior of associative model polymer solutions were determined as a function of molecular weight, solution concentration, shear rate, temperature, and solvent type in this investigation. These polymers are composed of a linear water soluble polyoxyethylene backbone chain extended with isophorone diisocyanate and end capped with hexadecyl groups, and have molecular weights ranging from 1.7x10(4) to 8.4 x 10(4) g/mole. For comparison purposes, poly(oxyethylene) resins of various molecular weights were also evaluated. A previously obscured mechanical terminal dispersion, which diminishes with increasing polymer concentration and decreasing temperature, has been clarified.