Efficacy of Poly(Lactic Acid)-Carbon Nanotube Nanocomposites Prepared by Reactive Processing of Maleic Anhydride Grafted Poly(Lactic Acid)

The mechanical properties of nanocomposites are usually influenced by the interfacial adhesion of the polymer matrix to the nanofiller. Several studies have shown that the weak interface promotes failure in the interfacial region due to ineffective strain transfer. An effective strategy to improve the performance of PLA is the addition of carbon nanotubes (CNTs). To improve the surface adhesion of PLA and carbon nanotubes, a benzoyl peroxide and maleic anhydride (PLA-g-MA) was prepared using a reactive process. The effectiveness of PLA-g-MA as a bulking agent for PLA/PLA-g-MA/CNT nanocomposites was verified.

The PLA and PLA-g-MA samples were characterized by Fourier transform infrared spectroscopy (FT-IR) to determine the grafting reaction of maleic anhydride on PLA chains, and the change of matrix PLA after graphitization reaction was demonstrated by rheological analysis. Thermal tests (differential scanning calorimetry and thermogravimetric analysis), mechanical tests (impact strength and tensile tests) and morphological characterization were used to verify the effect of the bulking agent. the distribution of CNT in the PLA matrix was better, as shown in SEM images, and the preparation of PLA/carbon nanotube nanocomposites using PLA-g-MA as a bulking agent proved to be effective. Thus, the addition of PLA-g-MA contributes to a greater distribution of CNT and can be used as an alternative for the production of PLA/CNT nanocomposites.

Figure the FT-IR infrared spectra of a maleic anhydride, PLA-g-MA, and PLA

Figure 2. SEM images of the PLA / CNT nanocomposites: (a) PLA-1CNT and (b) PLA-3MA-1CNT