SEDL / STP / STP1157-EB / STP15346S

Mechanical Properties of Amorphous and Roll-Drawn Polypropylene

McCammond, D
Professor, associate professor, and research associate, University of Toronto, Toronto,

Sinclair, AN
Professor, associate professor, and research associate, University of Toronto, Toronto,

Sinclair, LA
Professor, associate professor, and research associate, University of Toronto, Toronto,

Pages: 20    Published: Jan 1992

Download this paper for $25 PDF (296K)          View License Agreement
Abstract

Mechanical properties of both amorphous polypropylene and roll-drawn polypropylene sheet are examined using four experimental techniques: creep, transverse vibrating cantilever beam, axially resonating rod, and ultrasonic time-of-flight. Variations of the principal dynamic moduli were determined over 14 decades of frequency, at a single temperature. The ultrasonic time-of-flight technique yielded the dynamic and shear moduli at 5 MHz for all three principal axes of the roll-drawn sheet; the results indicated the material to be transversely isotropic. The three-dimensional stiffness matrix was populated at 5 MHz; its two-dimensional counterpart was then compared to the 0.01 Hz stiffness matrix of Sinclair and McCammond.