The abiotic and biotic degradation of poly(lactic acid) -- PLA film and PLA films compounded with two nanoclays - montmorillonite (MMT) and organomodified MMT (OMMT), and a surfactant - stearyl bis(2-hydroxyethyl) methyl ammonium chloride (QAC) was evaluated in inoculated and non-inoculated vermiculite, and a simulated compost environment (58 +/- 2°C, 50 +/- 5% RH). All films were produced in-house with approximately the same number average molecular weight (Mn), crystallinity, and thickness. After full thermal, morphological and physical characterization, the Mn and evolved CO2 were used as the key parameters to track the evolution of the abiotic and biotic processes, respectively. The abiotic stage was not significantly altered due to the presence of nanoclays, and the biodegradation rates of the PLA and PLA nanocomposite films were not modified as opposed to the claims made by the studies conducted before. There was no reduction in lag time of PLA due to the addition of nanoclays. The biodegradation test in a simulated compost environment showed higher mineralization for PLA films with QAC as compared to PLA films with MMT and OMMT, due to the presence of two alkyl (tallow) tails imparting more hydrophilicity and plasticization effect. Similar results were seen in the inoculated and non-inoculated vermiculite. The hydrolysis experiment was conducted to decouple the abiotic/ hydrolytic phase of biodegradation at 58 +/- 2°C, and the addition of nanoclays did not improve the degradation of PLA. Overall, the inclusion of nanoclays did not enhance the hydrolytic degradation or biodegradation of PLA films.
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