Water-absorbing materials based on polymer hydrogel and bentonite

The article deals with the production, sorption and rheological properties of composite materials based on polymer hydrogel and bentonite. It is shown that bentonite prevents the collapse of the hydrogel in aqueous solutions of electrolytes and leads to an increase in the moisture content after the collapse. After several repeated cycles of swelling in water, followed by drying at 60 and 110 °C, the degree of swelling of the composite is higher than that of the hydrogel. In the temperature range from 20 to 40 °C, the polymer hydrogel and the composite are able to withstand at least ten cycles of swelling and drying without changing the degree of swelling.