Abstract
The volumes of polymeric gels in equilibrium with alcohol (methanol, ethanol or propanol)-water solutions were observed by using a microscope. The concentrations of alcohol inside and outside gels in equilibrium were also measured. The three kinds of gels Sumikagel S-50 (-COONa), Amberlite IR-120B (-SO3Na) and Amberlite IRC-84 (-COONa) were used in this work.
From the experimental measurements, it was found that Sumikagel S-50 showed large volume change according to alcohol concentrations and discontinuous volume- phase transition. The alcohol concentrations inside the gel in shrinked state were much smaller than those outside the gel. No significant difference of the alcohol concentration was observed between inside and outside the gel in swelling state. For the ion-exchange resins, these phenomena were not found. The behavior mentioned above seems to be due to the structures of the polymeric gels and the interactions between polymer segments and alcohol molecules.
