SBIR Phase I:Synthesis and Characterization of Amphiphilic Graft Copolymers for Utility as Thermoplastic Hydrogels

What is the intellectual merit of the proposed project? This Small Business Innovation Research Phase I project will establish the feasibility of producing a novel class of amphiphilic graft copolymers to serve as thermoplastic hydrogel copolymers. Thermoplastic hydrogels are not available commercially and would be of great interest because, unlike conventional cross-linked hydrogel materials, they can be processed from solution or thermally into any form/shape via solvent casting, extrusion, thermoforming or hot melt injection. The proposed technology innovation will be achieved by the design of a series of amphiphilic graft copolymers with well-defined, adjustable macromolecular architectures with and without antimicrobial pendant groups along the chain. The project will explore a range of chemical compositions with variations in the chemical nature and concentration of hydrophobic grafts. The base polymer, poly(2-ethyl-2-oxazoline), is a commercially available polymer that is thermally stable, amorphous, water soluble, extrudable polymer. Physical crosslinks will be achieved by microphase separation. In the presence of water the hydrophilic backbone will swell. The degree of swelling and mechanical properties will be controlled by adjusting the macromolecular architecture tailored to the desired application requirements. What are the broader/commercial impacts of the proposed project? The broader/commercial impact of this project will be to develop processible hydrogels tailored for specific applications for wound care, water purification membranes, ink jet receptive layers for printing and thermoform contact lenses. The ability to tailor the properties of these materials by controlled synthetic methods using living polymerization methods will greatly enhance their utility to serve these diverse industries. Thermoplastic hydrogels can be processed, whereas cross-linked hydrogels are insoluble and infusible. Low cost processing methods such as thermoforming, injection molding or extrusion offer significant economic advantage over many current hydrogel products on the market. Moreover, the ability to adjust the composition and tailor the hydrophilic/hydrophobic nature and microphase separation, which controls the degree of swelling, will enable the optimization of performance for a wide range of potential applications. The incorporation of non-leaching antimicrobial groups along the chain will enhance their utility in wound care and water purification membranes. Investigation of the surface and bulk morphology correlated to physical and thermo-mechanical data will help to obtain a better understanding of structure-property relationship of amphiphilic graft copolymers as a function of composition and observed morphology.