Physical Evaluation of Explanted Vascular Prostheses

The authors attempt to describe a comprehensive study of physical ageing in vivo on the properties of explanted prostheses. Infrared spectroscopy (FTIR) technique has been used to compare the molecular conformation of various polyethylene terephthalate (PET) yarns extracted from the different areas of the prostheses (with different lifetimes) collected after ageing. The FTIR found results showed an increased PET crystallinity related to the development of microcrystallites in the amorphous areas of PET chains. Nevertheless, these small crystallites are not perfectly orientated according to the fiber axis. In addition, we can deduced that the ruptures in macromolecular chain can occur in the diethylene glycol groups existing in the zones amorphous and can be induced the crystallization process.