The static and dynamic properties of a range of molecular weights (2 x 10(4) to 1.6 x 10(5) g/mol) of poly(benzyl methacrylate) have been assessed in four different imidazolium- and pyrrolidinium-based ionic liquids over a wide temperature range (27-155 degrees C), primarily using light scattering techniques. All four systems exhibit lower critical solution temperature phase behavior. The relevant structural, dynamic, and thermodynamic parameters were examined as a function of concentration, temperature, and molecular weight. Some interesting observations were revealed. The phase boundaries suggest a shift of the critical composition toward the polymer-rich region, in contrast to the low critical concentrations for polymers commonly observed in polymer solutions. Surprisingly, the second virial coefficient (A(2)) remains positive, even at temperatures close to phase separation, where A(2) < 0 is anticipated. Furthermore, A(2) also shows stronger dependence on molecular weight than commonly observed for polymers in good solvents. On the dynamic side, the diffusion virial coefficients (k(d)) remained positive over the given temperature range, further corroborating the apparent good solvent behavior of A(2). The excluded volume exponents (v approximate to 0.53-0.54) obtained from the dependence of hydrodynamic radii on molecular weight also indicate good solvent characteristics.