Adsorption behavior of cationic polymers on bentonite

The adsorption behavior of a series of cationic water-soluble polymers poly(diallyldimethylammonium chloride) with different molar masses onto raw bentonite was investigated through the elaboration of their adsorption isotherms and the quantification of the water content of the clay/polymer complexes formed. It was found that the type of adsorption isotherms obtained depends on the chain length of the polymer. The study showed a correlation between the amount of adsorbed polymer and the water content of the clay, after the adsorption experiments. The lower the molar mass of the polymer used, the larger was the reduction on water content of the complexes.