The Preparation and Characterization of a Compatibilizer: Silicon Dioxide Nanoparticles Grafted with L-Lactic Acid Oligomer

It is found that the blending of inorganic materials and organic materials are usually thermodynamically immiscible with each other. The compatibility between the two blending materials can be enhanced by adding a component which is miscible with both parent materials. Therefore, the as-synthesized silicon dioxide grated by L-lactic acid (OLLA-g-SiO₂) was used as a compatibilizer to enhance the compatibility of the PLLA and silicon dioxide (SiO₂). In the paper, we prepared OLLA-g-SiO₂ by using Tin (II) 2-octanoate Sn(Oct)₂ as catalyst. Meanwhile, the surface-grafting reaction was characterized by Fourier transform infrared spectrometry (FTIR) and thermogravimetric analysis (TG). We also studied the mechanical properties of the composite PLLA/OLLA-g-SiO₂/SiO₂ films which can be used as package materials. It was found that the tensile strength of PLLA/SiO₂ films could still be kept when OLLA-g-SiO₂ were introduced, even if there were a large amount of SiO₂ nanoparticles (>10 wt%) during blending. So the OLLA-g-SiO₂ could be used as a compatibilizer in the films prepared by blending PLLA with SiO₂.