Preparation of super-strong and high tough poly(vinyl alcohol) basedhydrogels trough fully physical cross-linking by using agar ,tannic acid andsoaking in NaCl aquoes solution

High tough poly(vinyl alcohol) (PVA) based hydrogels were prepared using agar and tannic acid(TA)by repeated freezing/thawing processes and subsequently soaking in saturated NaCl aqueous solution.The PVA hydrogels were characterized via tensile testing. The results show that the tensile stress andtoughness of PVA single network are only ۴.۸۵ MPa and ۷.۸۹ MJ/m۳, respectively. By using agar,TA and soaking in NaCl solution, the tensile stress and toughness increase to ۱۸.۲۸ MPa and ۵۲.۴۲MJ/m۳, respectively. These super-strong and high tough PVA based hydrogels were prepared troughsimple physical interactions, instead of toxic chemical cross-linking and thus might be considered asa favourable candidate for biomedical applications

کلیدواژه ها:

Biopolymers ، Salting-out effect ، super-strong hydrogels