Shape Memory Biomaterials Prepared from Polyurethane/Ureas Containing Sulfated Glucose

Covalently crosslinked polyurethane/urea polymers were synthesized using diamine monomers modified with pendant glucose groups and 2,4-toluene diisocyanate, poly(ethylene glycol) (PEG), and 1,1,1-tris(hydroxymethyl)ethane (triol) comonomers. The polymers showed shape memory behavior with a switching temperature dependent on the glass transition temperature. The glass transition temperature is tuned by varying the mole ratio between the glucose-diamine and PEG used in the polymerization. Increasing PEG content resulted in decreasing glass transition temperature, and a glass transition temperature of 39 degrees C, close to physiological temperatures, was obtained. The fixed shape showed gradual shape recovery behavior, but a fixity of 70% was achieved when the material was stored at 25 degrees C. The polymer recovered to the permanent shape when heated to 50 degrees C. Finally, the surface of a film of the polymer can be sulfated to achieve increased blood-compatibility without sacrificing the shape memory properties. (C) 2015 Wiley Periodicals, Inc.