Comparison between static (sorption) and dynamic (IGC) methods in the determination of interaction parameters in polymer/polymer blends

Polymer-polymer interaction energy densities have been measured by two diff erent techniques: inverse gas chromatography (IGC) and gas sorption experim ents in a Cahn electrobalance. Both use a third component as a molecular pr obe to investigate the interactions between the two polymers. The poly(epic hlorohydrin)/poly(methyl acrylate) (PECH/PMA) blend has been selected as a system that ensures the liquid state of the polymeric phase in all the expe riments. It also stresses the convenience of a previously proposed procedur e that selects the most adequate solvents to obtain a reliable polymer-poly mer interaction energy density by IGC. A permanent gas, CO2, has been used as molecular probe in sorption measurements, after verifying the inconvenie nce of using organic solvents as probes, due to the overshoot phenomena obs erved in their sorption kinetics. Both techniques give similar polymer-poly mer interaction values.