ABSTRACT

Poly (L-Lactic Acid) (PLLA) has excellent bioresorbable properties and applied in manufacturing Bioresorbable Vascular Scaffold (BVS). In order to improve the mechanical performance of PLLA BVS, biaxial orientation via stretch blow moulding process has been introduced to present products with thinner but stronger struts. In order to better understand this deformation process above the glass transition, the mechanical behaviour of amorphous PLLA materials was obtained by biaxial stretch testing under displacement controlled conditions. The Glass-Rubber (GR) constitutive model was adopted to simulate its nonlinear viscoelastic behaviour and showed its ability for the simulation of blow forming process.