Chitin- polyurethane networks: correlations between physical properties and composition

Aiming to combine the bioproperties of chitin with the mechanical characteristics of polyurethane these two polymers were interconnected through a tridimensional network. The networks were formed from the addition reaction of the terminal isocyanate groups of a urethane prepolymer and the acetamide and hydroxyl groups of chitin. The crosslinking density was set from the ratio between the reacting groups, since the polyurethane length was kept constant (Mw = 66 kD, Mn = 48 kD). The biodegradability of polyurethane was afforded by the polycaprolactone segment of this component. The physical properties of the networks were analyzed in correlation with the composition, and compared with previous results obtained from blends with the same composition.