Thermodynamic perturbation theory: Sticky chains and square-well chains

We extend Wertheim's first-order thermodynamic perturbation theory [J. Chem. Phys. 87, 7323 (1987)] to sticky chains and square-well chains. The predicted compressibility factors for square-well chains are found to agree with Monte Carlo data. We demonstrate that the effect of chain connectivity is to reduce the attraction contributions to the compressibility factor and to the critical temperatures.