A series of AB/AB(2) etherimide copolymers of nearly constant weight-averaged molecular weight, synthesized from starting comonomer compositions ranging from 0 to 1 mole fraction AB (x(AB)). were characterized. Zero-shear viscosity of various concentration solutions in N-methyl pyrrolidinone showed a slight increase with x(AB) in the range of 0.00 less than or equal to x(AB) less than or equal to 0.80, followed by a sharp rise at higher x(AB). Likewise. the solution flow birefringence showed negligible response for x(AB) < 0.80, followed by a rise with x(AB) at higher fractions. The dilute concentration, zero shear viscosity, and intrinsic viscosity correlated directly with the calculated distance between branches (integral (AB)). The zero-shear viscosity, eta (0), exhibited a linear dependence on concentration in the dilute regime for the entire series of branched polymers and a power law dependence in the concentrated regime, with the coefficient increasing with x(AB). The concentration dependence of eta (0) also scaled with the product of the concentration and intrinsic viscosity (c[eta (0)]), indicating that, over the range of concentrations studied, the architectural dependence of the viscosity is well described by [ eta (0)]. Likewise, increased viscoelastic effects were observed with x(AB) in steady shear and oscillatory flows. Taken together, these results clearly indicate a transition in the dynamics from unentangled, hyperbranched polymer behavior to entangled, linear-like behavior occurs at a critical starting monomer composition, x(AB) similar to 0.80.