Berlin 2001 – scientific programme

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CPP: Chemische Physik und Polymerphysik

CPP 19: Poster: New Methods, Thin Polymer Films, Monolayers

CPP 19.35: Poster

Thursday, April 5, 2001, 12:30–15:00, AT1

Ablation of PHB/PCL and PLLA/PCL blends by ultrashort laser pulses for laser cutting of polymer stents — •Baerbel Becher, Detlef Behrend, and Klaus-Peter Schmitz — Institute of Biomedical Engineering, University of Rostock, E.- Heydemann- Str. 6, 18055 Rostock

We present a laser cutting process adapted to produce cardiovascular polymer stents. Coronary stents are specially structured tubes with a diameter of 1 to 2 mm, which prop open artery walls of patients whose arteries are narrowed, occluded or have collapsed. The stent is expanded by inflation of a balloon catheter and fixed within the stenosed vascular area. The response of the stent to the mechanical stress caused by the balloon inflation is mainly influenced by the mechanical properties of the used material.

The aim of our study was to minimize the affected zone (AZ) caused by the laser cutting. Our investigations focused on the interaction of the polymer foils (PHB/PCL and PLLA/PCL) with the ultrashort laser pulses of a Ti:sapphire laser. We compared our results to the modifications caused by the pulses of a CO2 laser. The width of the AZ was measured with a polarization optical microscope.