Tailored one-way and two-way shape memory capabilities of poly(ε-caprolactone)-based systems for biomedical applications

摘要

Shape Memory Polymers (SMPs) are a class of smart materials, capable of significant shape variations on the application of an environmental stimulus. SMPs present various advantages with respect to their metallic and ceramic counterparts, such as processing at a low costs, large recoverable strains and mechanical properties close to those of soft biological tissues. SMPs can be potentially employed in biomedical applications and minimally invasive surgery devices, where a single deployment is required ("one-way" shape memory effect), are the most frequently investigated [1]. Also the "two-way" shape memory behavior, i.e. the triggered variation between two distinguished shapes on the application of an on-off stimulus, is recently demanded, since it may fulfill the requirements for the development of actuators or artificial muscles [2]. To this end polymers like poly(s-caprolactone) (PCL) are considered promising systems, due to their biodegradability and to the possibility to present, when cross-linked, reversible actuation under specific thermo-mechanical conditions [3]. In this work we have explored the one- and two-way shape memory capabilities of a novel type of covalently cross-linked semicrystalline systems, prepared by a sol-gel approach from alkoxysilane-terminated PCL.