Deformation Behavior under Static and Cyclic Tension of Polymer Grafts without and after Modification by RGD Peptides

The structure, mechanical properties, and deformation behavior under static and cyclic tension of biofunctionalized biodegradable vascular grafts based on polyhydroxybutyrate/valerate and polycaprolactone were studied. It is shown that the modification gives rise to an almost twofold decrease of the elongation at break as well as the ultimate strength. It is shown that under cyclic loading the modification of grafts results in decreasing cyclic durability by more than twice. In doing so, the level of deforming stress decreases to a much lesser extent and is practically inferior to that for unmodified material. The analysis of principal strain ε₁ and ε₂ component distribution patterns in grafts of both types is carried out while the reason for the observed changes is discussed.