The swelling in water of complexes of montmorillonite with polyvinyl alcohol

Abstract

The swelling in water of complexes of sodium and calcium montmorillonite with polyvinyl alcohol has been studied. The polymer reduced the swelling of the clay. The extent of reduction was dependent on the properties of the polymer, the conditions in which the adsorption of the polymer took place, and the previous history of the clay. The swelling of the montmorillonite-polyvinyl alcohol complex at low hydrostatic suctions did not fall below 50% of that of the parent clay, whilst sorption of water from the vapour phase was only reduced by about 15%. These results indicate that the polymer is adsorbed around clay crystals or domains, within which swelling can still occur, although adsorption of water between domains is restricted.