June 1971 An Experimental and Analytical Investigation of the Ductile Fracture of Polymers H. F. Brinson, H. Gonzalez, C. W. Stormont Department of Engineering Mechanics This Research was supported by the National Aeronautics and Space Administration, Grant Number NGR-47-004-051with NASA-Ames, Moff ett Field, California. College of Engineering, Virginia Polytechnic Institute and State University t