Abstract
A facile one-pot method was developed to synthesis thermosensitive PNIPAAM/Ca-alginate IPN hydrogels. With the method, the crosslink of alginate by Ca2+ and polymerization and crosslink of NIPAAM occurred in a single reactor at the same time upon the all the reactants were added to the reactor. CaSO4•2H2O was used as the crosslinker for alginate and it avoided the quick gelation thus lead to the homogeneous structure of the hydrogels. Compared with the conventional subsequent IPN strategy, the one-pot strategy was facile and required much less time. The mechanical properties of the IPN hydrogels were improved significantly compared with IPN hydrogels without CaSO4·2H2O and it could be adjusted by the dosage of CaSO4·2H2O. The result of FTIR indicated that the hydrogels obtained comprise PNIPAAM and Ca-alginate. The SEM presented a typical porous structure of IPN hydrogel. The temperature-sensitive behaviors and deswelling kinetics of the hydrogels were also discussed. The method which is a simple, time-saving, to prepare IPN-based NIPAAM hydrogels and other IPN hydrogels is of great potential to be applied.