BS in Materials Engineering
Materials Engineering Department
Trevor Harding, Ajay Kathuria
Poly(lactic acid) (PLA), a well-known biopolymer, is lacking in barrier properties and toughness. The research goal of this project is to look at the crystallinity of PLA when combined with metal organic framework (MOF). It is speculated that MOF has an effect on PLA chain mobility, and therefore crystallinity. In this study, aluminum MOF was added to PLA in varying concentrations (0, 0.5, 1, 2, 5, 10, and 20 wt%) to observe the crystallinity of the composite. The resulting PLA-Al-MOF composite films were characterized using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). SEM was used to characterize the PLA-Al-MOF interfacial adhesion and MOF dispersion. DSC and FTIR showed a decrease in crystallinity with increasing MOF content, while XRD revealed a crystallinity average of 20.43% with no statistical difference among the samples. Overall, lack of correlation between data obtained from the different characterization methods led to inconclusive results. It is recommended that future investigators use polarized light microscopy (PLM) as it is a direct measure of crystallinity and thermally process the films to mimic DSC conditions before performing XRD to help solidify a more concrete correlation between MOF and PLA crystallinity.