Study of the mechanical behavior of Z-structure stents produced by poly-L-lactic acid multi-ply strands

Biodegradable polymer stents are attracting more attention with their advantages of biocompatibility and biodegradable and dispensing with surgical removal. However, the lower radial force is the main bottle neck of their application. In the present research, poly-L-lactic monofilaments with three different diameters were adopted to produce multi-ply strands and then fabricated into Z-structure stents. The effects of strand parameters on stent radial force were studied. The monofilament, strand and stents were subsequently degraded in vitro for 48 weeks. The thermal properties, morphology change, mass retention and strength retention of samples were recorded to forecast the long-term application effects of the stents. The results of this research provided theory to optimize the processing technique of stents with a textile structure to acquire higher radial force.