# Accession Number:

## AD0618989

# Title:

## A THEORY OF THE THERMODYNAMIC BEHAVIOR OF NONELECTROLYTE SOLUTIONS. III. THE OSMOTIC PRESSURE OF POLYMER SOLUTIONS,

# Descriptive Note:

# Corporate Author:

## CASE INST OF TECH CLEVELAND OHIO

# Personal Author(s):

# Report Date:

## 1959-08-27

# Pagination or Media Count:

## 14.0

# Abstract:

Data on the osmotic pressures of both dilute and concentrated polystyrene and polyisobutylene solutions in various solvents were examined in terms of Marons theory. It is shown that for each polymer-solvent system at a given temperature the behavior over the entire concentration range studied can be characterized by a single interaction parameter, mu, whose dependence on volume fraction, v2, of polymer is given by mu mu-o sigma-ov2, where mu-o and sigma-o are constants. For two systems, where data are available, this linear relationship was found to hold from v2 0 up to v2 0.90. With this relationship for mu, Marons theory leads to functional plots for dilute solutions which are linear even in systems where the usual IIC vs. C plots are not straight lines. These plots yield the molecular weights from the intercepts and the quantities mu-o -- sigma-o from the slopes. However, the individual values of mu-o and sigma-o cannot be obtained from the dilute solution data. To arrive at these, data are required at concentrations higher than those customarily used for molecular weight determinations. Author