Chapter 2
SAFT-D: a new equation of state
for polymers based on SAFT
2.1 Introduction
As mentioned in the previous chapter, SAFT was developed by Chapman et.
al. [46, 47] as an extension of Wertheim’s TPTl [26, 27, 28, 29] for associating atomic
fluids to chain-like molecules. This original derivation of SAFT is for hard chain
fluids, where all the segments in the chains are purely repulsive hard spheres. Thus,
the reference fluid is the fluid of hard spheres. The hard chain EOS, which will
be referred to as SAFT-HS in this dissertation, accounts for two most important
interactions among the segments of chain molecules: chain connectivity and excluded
volume. Comparisons with simulation results show that SAFT-HS is an excellent
EOS for hard chain fluids. However, to develop an EOS for real systems, attractive
32