Smart lignin hydrogels with pH responsive and magnetic properties was prepared by free radical polymerization from lignin and acrylamide. In order to improve its swelling properties, calcium carbonate as pore- foaming agent was introduced to the polymer formulation, then magnetic particles (Fe3O4) was formed in the polymer by in situ reaction and co- precipitation. The results showed that degree of swelling of pH responsive hydrogels (PLH) containing the pore-foaming agent increased 47% compared to the original hydrogels (OLH) without pore-foam...
