? We propose to develop novel shape memory polymer (SMP) foams that have unique mechanical characteristics particularly well suited for biomedical applications. Specifically, it is our hypothesis that the polymer shape memory effect can be enhanced by structuring SMPs into open cell foams, thus creating novel actuator materials with unique combinations of extremely high recoverable strain, low recovery force, and low energy consumption for actuation. Further, we propose to apply basic work on SMP foam actuator structure/property relationships to a mechanical thrombectomy device. Such a device should significantly improve peripheral occlusive disease treatment and reduce complications due to relative ease and speed of delivery, decreased risk of hemorrhage and distal embolization, ability to shape the device to match vessel diameter, ability to completely remove occlusion, and dramatic reduction in cost of procedure. The long-term goal of this project is to deliver clinical prototype devices that can begin FDA clinical trials. The primary deliverables and locations for the work for the Phase I study are: The primary deliverables and locations for the work for the Phase I study are: 1. Establish a foam process for SMP that produces cylindrical SMP foam structures with radial expansitivites up to 10 x (100x expansion of cross-section), average pore size (20 to 100 microns), narrow pore size distribution, and axial flow channels via the templated foam process. (LLNL) 2. Measure and document SMP foam structure and thermomechanical properties. (LLNL) 3. Fabricate foam actuator system. (LLNL/Sierra Interventions) 4. Demonstrated SMP foam device actuation in vascular model with flow. (Sierra Interventions). ? ?
