A Study is done on the influence of fumarate-based thickeners on the rheological behavior of low-molecule-weight poly(ethylene glycol) dimethacrylate monomers diluents, often used as major components in the formulation of anaerobic adhesives. These solutions generally showed pseudoplastic behavior. The cross equation was selected to determine the viscosity vs. shear rate curves. at constant temperature. The final equation relates the viscosity as a function of shear rate and thickener concentration. In addition, the zero shear rate viscosity evolution as a function of the thickener weight traction was studied, showing that two critical concentrations were present.