The proposed program is aimed at developing strong tough ordered polymer films for flexural fatigue loading. Ordered polymers have been developed by the u.S. Air force primarily as high strength lightweight aerospace structural materials, but they can provide major improvementsin biomedical applications as well. The long term objective is to evaluate the potential of the ordered polymer pbzt (poly p-phenylene benzobisthiazole) to provide a durable heart diaphragm, exceeding the fatigue life of current materials. Pbzt film has an oriented, interconnected "molecular fabric" that promises to have extremely high flex life as well as high strength because of its unique microstructure. A flexlife test rig that achieves a suitable balance between speed of testing and proper flexural excursion will be designed, built and evaluated. Pbzt will be evaluated for flexural fatigue life in comparison witha polyurethane currently used in artificial blood pumps.
