Fabrication of Poly-l-lactide Biomaterials with High Mechanical Properties Using Fiber Oriented Pressing

A new technique of dilute solution spinning to obtain poly-l-lactide (PLLA) fiber was presented. PLLA materials were fabricated by using fiber oriented pressing and the effects of pressing pressure and temperature on the mechanical properties and weight average molecular mass of PLLA were investigated. Good oriented fibers with porous structure (0.1 ～ 1 μm) were obtained by a dilute solution spinning method. Bending and shearing strength of PLLA samples first increase and then decrease with the increase of pressing temperature and pressure. The bending strength, shearing strength, and bending modulus reach 238.8 ± 6.5 MPa, 127.5 ± 3.5 MPa and 3.25 ± 0.25 GPa, respectively, if the pressing temperature is 185°C and the pressure is 130 MPa. These values are greater than conventional pressing methods. In addition, the decrease in weight average molecular mass (19.5%) that results from using oriented pressing is lower than that seen (30.0%) by using the conventional pressing method.