Hydrolytic degradation behavior of poly(l-lactide)/carbon nanotubes nanocomposites

In this work, poly(l-lactide)/carbon nanotubes (PLLA/CNTs) nanocomposites were prepared through the common melt-blending processing. The morphologies of the nanocomposites were characterized using scanning electron microscope (SEM). The hydrophilicity of the sample surface was evaluated by the measurement of the contact angle of compression-molded film. Different annealing temperatures were applied to prepare the nanocomposites with different degrees of crystallinity. The results show that CNTs exhibit homogeneous distribution in the PLLA matrix, and the hydrophilicity of the sample surface increases gradually with the increasing content of CNTs. CNTs exhibit excellent nucleation effect for the cold crystallization of PLLA, but the crystalline form of PLLA matrix is mainly determined by the annealing temperature. Study on the hydrolytic degradation behaviors of the nanocomposites show that the presence of CNTs greatly improves the hydrolytic degradation ability of the PLLA matrix. The degree of the hydrolytic degradation and the corresponding crystalline structures during the hydrolytic degradation process are greatly dependent upon the content of CNTs.