SELF-HEALING AND SHAPE-MEMORY HYDROGELS OBTAINED BY FREE RADICAL MICELLAR POLYMERIZATION

In this work we prepared physically crosslinked hydrogels by radical micellar polymerization. This type of polymerization involves the use of a hydrophilic monomer (Acrylamide), a hydrophobic monomer (Octadecylacrylate), a surfactant (Sodium dodecyl sulfate), and a salt (NaCl). To improve mechanical properties, a multifunctional hydrophobic monomer (divinylbenzene) was used with the aim of creating branched chains. Three series of five samples each were prepared by varying, within the series, the amount of Octadecylacrylate (C18A), and, within the series, the amount of Divinylbenzene (DVB). As the concentration of C18A increases, the amount of water present at equilibrium inside the hydrogels de-creases, the melting and crystallization enthalpies increases and an increase is also seen in mechanical shear modulus G'.