Modeling the Thermo-Mechanical Response of Shape Memory Polymers

MODELING THE THERMO-MECHANICAL RESPONSE OF SHAPE MEMORY POLYMERS

Abstract

Shape memory polymers are novel materials that can be easily formed into complex shapes, retaining memory of their original shape even after undergoing large deformations. These new materials are finding increasing use in a number of cutting edge applications ranging from actuators, MEMS devices, biomedical devices to space technology. In spite of their technological significance and in marked contrast to the situation in shape memory alloys, there is a dearth of constitutive models that are able to predict the thermomechanical behavior of shape memory polymers undergoing complex thermal and mechanical loadings. The availability of models that will aid in predicting their behavior under a wide range of conditions and are essential for designing applications using these polymers. The aim of the research proposed here is to formulate a properly invariant three-dimensional constitutive theory within a thermodynamic setting that is capable of predicting the thermal and mechanical behavior of crystallizable shape memory polymers under a variety of conditions. The models developed will then be implemented into a finite element program to study the response of shape memory polymers in realistic geometries and conditions. The models and the computational algorithms that are developed will help in understanding the behavior of shape memory polymers and hasten the use such materials in novel technological applications.