Characterization of the Microstructure and Mode I Fracture Property of Biodegradable Poly(L-lactic acid) and Poly(ϵ-caprolactone) Polymer Blends with the Additive Lysine Triisocyanate

Biodegradable polymer blends of poly(L-lactic acid) (PLLA) and poly(ϵ-caprolactone) (PCL) with the addition of 2 phr lysine triisocyanate (LTI) were investigated using the Fourier transform infrared (FT-IR) spectroscopy, field-emission electron scanning microscope (FE-SEM), and mode I fracture testing technique. It was found that the addition of LTI dramatically improved the phase-separation morphology of the PLLA/PCL blends, hence increase the mode I fracture properties. The FT-IR analysis suggested that LTI acted as a compatibilizer by inducing secondary interaction between the NCO groups of LTI with the OH groups of PLLA and PCL.