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Shape memory polymers are stimuli responsive materials with their shape can be temporarily changed and fixed into certain shape. Once applying some stimuli such as heat, light, chemicals, pH change etc., they can quickly recover back to the original shape without any external force needed. Due to this excellent flexibility of shape, shape memory polymers are widely investigated as promising novel materials in various fields. This dissertation is mainly based on the work of synthesis, characterization and modification of shape memory polyurethane/ureas with sulfated sugar units for potential blood contacting applications. First, covalently crosslinked polyurethane/urea polymers were synthesized using diamine monomers modified with pendant glucose groups and 2,4-toluene diisocyanate (TDI), poly(ethylene glycol) (PEG) and 1,1,1-tris(hydroxymethyl)ethane (triol) comonomers. The polymers displayed 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. The polymer recovered to the permanent shape when heated to 50 °C. Finally, the surface of a film of the polymer can be sulfated without sacrificing the shape memory properties.Then, this type of shape memory material with anticoagulant surfaces was processed into highly interconnected foam structure by solvent casting/particulate leaching technology. The synthesized foams good shape memory behavior as evidenced by fixity and recovery values. The materials properties of the foams can easily be tuned by varying the template used to prepare the foam. The heparin-inspired polymers impart excellent resistance to platelet adhesion indicating excellent blood compatibility of the material surface.At last, the synthesized shape memory polymer foams were composited with hydrogels based on HEAA, AA, NIPAM, and combination of AA and gelatin. The hydrogel was well dispersed in the foam cells characterized by SEM. The hydrogel incorporated SMP foams gave significantly enhanced fluid up take while remaining the shape memory effects. Moreover, ascorbic acid as example drug can be loaded into the composite material and gradually released out over 48 h.

The overall goal of this thesis was to investigate the synthesis and characterization of elastomeric polymer networks crosslinked by ion-pairs. To generate these networks, cationic polyacrylate ionomers with styrene sulfonate counter-ions were synthesized. These polymers were used to generate ionically crosslinked networks by copolymerization of the pedant vinyl ionomers with acrylate monomer. These ionically crosslinked elastomers swelled in organic solvent like covalently crosslinked elastomers, but could be dissolved and re-gelled by dissociating and re-associating the ionic bonds by double ion-exchange reactions under acidic and basic conditions. Uniaxial tensile testing and oscillatory shear rheology were used to characterize the mechanical properties of the materials and compared to covalently crosslinked control samples. In contrast to the covalently crosslinked polymers, the ionically crosslinked samples showed strong property dependence on temperature and level of strain. At room temperature, the ionically crosslinked polymer had similar properties with a covalently crosslinked elastomer. As the temperature was increased above 100oC, the fluid-like property became more and more obvious due to the rearrangement of the ionic bonds. In addition, under load the ionically crosslinked polymer also exhibited flow. This mechano-chemical response of the materials to reconfigure the network under thermo-mechanical load should provide opportunities for developing new processable and self-healing elastomers using ionic interactions.