Solutions of ideal thermoreversible associating polymer chains are analyzed by standard Metropolis Monte Carlo simulations. The associating units are restricted to form only pairs and are located at the ends of each chain. Two cases are considered: equilibrium chemical association and diffusion limited association. Thermodynamic and structural quantities obtained in the simulations are directly compared to predictions of a mean field theory. Finite size effects when considering loop-like structures are addressed for the case of equilibrium chemical association. (c) 2005 Wiley Periodicals, Inc.