PVP, a synthetic polymer and chitosan, a natural polymer are biocompatible and have presented a great variety of interesting properties for cosmetic, biomedical, pharmaceutical and biotechnological applications, Many alternatives to improve the polymer propeties has been made as bleeding polymers, for example. In this work, two different techniques of hydrogel attainment were used: one from mixtures of acid aqueous cosolutions of chitosan and PVP, whose resultant films and solutions were irradiated, afterwards, by ultraviolet radiation (λ = 254 nm), another one from the reaction of poly (N-vinyl-2-pyrrolidone-co-acrolein)-a novel copolymer synthesized in our biomaterials laboratory-and chitosan. In the first one alternatives it was possible produce hydrogels directly from mixtures of aqueous acidic co-solutions of both polymers. In the second one, the attainment of hydrogels from Schiff base has proved to be an effective methodology for the production of hydrogels, showing good values of gel content and swelling.
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