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Critical Compressibility Factors for Chain Molecules



L L. Lue, Daniel G. Friend, J. R. Elliott


For many equations of state for fluids composed of chain-like molecules, the compressibility factor is related to the chain number concentration only through the total monomer concentration. For these theories, we find that the critical compressibility factor approaches one-third in the limit of infinitely long chains, contrary to experimental trends. This behavior can be attributed to inaccurate scaling of the virial coefficients of these equations of state with respect to chain length near the critical temperature. Appropriate scaling leads to the proper trend for the compressibility factor, as demonstrated with a simple equation.
Molecular Physics
No. 18


critical point, equation of state, polymer, scaling behavior


Lue, L. , Friend, D. and Elliott, J. (2000), Critical Compressibility Factors for Chain Molecules, Molecular Physics (Accessed July 18, 2024)


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Created August 31, 2000, Updated October 12, 2021