This study presents the testing techniques used to thermomechanically characterize the material behavior of a shape memory polymer as well as the resulting data. An innovative visual-photographic apparatus, known as a Vision Image Correlation system was used to measure the strain. A series of tensile tests were performed on specimens in which strain levels of 10%, 25%, 50%, and 100% were applied to the material while above its glass transition temperature. After deforming the material to a specified applied strain, the material was constrained and cooled to below the glass transition temperature. Finally, the specimen was heated again to above the transition temperature, and the resulting shape recovery profile was measured. The dependence of the recoverable strain on the heating and cooling rate was investigated in this work. Results showed that strain recovery occurred in a nonlinear fashion with respect to temperature. Results also indicated that the ratio of recoverable strain to the applied strain was a constant value, and was independent of the level of applied strain.

Date Published: 23 April 2008
PDF: 9 pages
Proc. SPIE 6929, Behavior and Mechanics of Multifunctional and Composite Materials 2008, 69291B (23 April 2008); doi: 10.1117/12.776372

Published in SPIE Proceedings Vol. 6929:
Behavior and Mechanics of Multifunctional and Composite Materials 2008
Marcelo J. Dapino; Zoubeida Ounaies, Editor(s)