Abstract
High molecular weight terpolymers based on L-lactide (LLA), trimethylene carbonate (TMC) and glycolide (GA) are synthesized and characterized with the aim of assessing their potential in the development of bioresorbable cardiovascular stents. The effect of the composition on the thermal and mechanical properties of terpolymers is investigated in comparison with the corresponding PLLA-TMC copolymers as well as a PLLA homopolymer. Incorporation of GA units strongly decreases the crystallinity of PLLA-TMC-GA terpolymers due to its more random microstructure as evidenced by C-13 NMR. Meanwhile, the toughness is greatly improved, with only a slight loss of tensile strength. Plasma-treated poly[(L-lactide)-co-glycolide] (PLGA) fibers are used to reinforce the terpolymer matrix. Composite with 8 wt% fibers exhibits much higher tensile strength and modulus. A minitube is fabricated using a single-screw extruder, and a stent prototype is successfully manufactured from a terpolymer by a CNC engraving machine, thus showing the feasibility of the terpolymers for the development of bioresorbable cardiovascular stents. POLYM. ENG. SCI., 54:1418-1426, 2014. (c) 2013 Society of Plastics Engineers