Swelling clays, cross-linking

Lightly cross-linked polyacrylamide is used to make superabsorbents of water. Astarch-g-polyacryla-mide/clay superabsorbent composite has been synthesized [27] by graft copolymerization reaction of acrylamide, potato starch, and kaolinite micropowder (< 1 pm) followed by hydrolysis with sodium hydroxide. Such a superabsorbent of compositin 20% kaolinite, 20% potato starch, 60% acrylamide, 2% initiator (ceric amonium nitrate), and 0.04% cross-linker (N,N-methylenebisacrylamide) is found to absorb 2250 g H20/g at room temperature at swelling equilibrium. 

The solvent resistance properties of the montmorillonite-filled conjugated linseed oil-based nanocomposites have been studied in THE by the equilibrium swelling method at different temperatures. The diffusion coefficient of the nanocomposite systems depends on the composition, percentage of clay and temperature. The diffusion coefficient increases with an increase in the clay content and temperature. The cross-link density of the nanocomposites ranges from -101-237 x 10 mol/cm. ... 

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