Effect of P(LLA-CL) Blending on the Mechanical Properties of PLLA/PCL

Abstract

P(LLA-CL) copolymer was additionally blended to PLLA/PCL polymer blend to improve the immiscibility between PLLA and PCL. Mechanical properties such as the bending modulus, strength and the maximum J-integral were then measured and the phase morphology and fracture surface were observed using FE-SEM. Crystallinity values of PLLA and PCL were also evaluated using DSC. It is seen that those mechanical properties successfully increased due to P(LLA-CL) addition. The results of FE-SEM observation and crystallinity measurement suggests that the immiscibility is improved by P(LLA-CL) blending and as a result, spherulites of PCL dispersed in the blend are reduced, resulting in effective increase of ductile deformation. It is thought that this kind of phase structural change causes the improvement of the mechanical properties.