Investigation of Polyurethane Shape Memory Polymer for Potential Applications in Brain Aneurysm Treatment

Abstract

Intracranial aneurysms (ICAs) are abnormal deformations in the walls of cranial arteries that can rupture, resulting in hemorrhage and stroke. Modern ICA treatments minimize the risk of rupture by limiting blood flow into the aneurysm body, but current treatments are limited in their ability to provide long-term solutions for large and/or complex aneurysm geometries. Self-deploying devices made from porous shape memory polymer (SMP) materials could improve ICA treatment by allowing for a more stable and uniform occlusion of the aneurysm sac. This thesis discusses investigations into the chemical composition, physical structure, and manufacture of a polyurethane shape memory polymer (SMP) with potential applications in the design of an alternative ICA treatment device. The investigation demonstrates 1) composition dependent activation temperature and mechanical properties that can be tuned for medical applications, 2) a particle leaching synthesis procedure for the production of uniform open-cell SMP foam structures with high compressibility, and 3) a novel direct ink writing 3D printer prototype compatible with the thermoset polyurethane SMP material.