LAUSR

Poly(lactic acid) (PLA) is one of the most promising bio-based and biodegradable polymers. However, its processability and range of applications are limited by its low thermal stability. The novelty of this work is studying the thermal stability of two PLA/clay nanocomposites (PLA/Cloisite 20A and PLA/Cloisite 30B) as a function of the composition and the microstructure, which is exhaustively studied by performing quantitative electron tomography (ET). Quantitative ET involves image acquisition, reconstruction of the volume and a subsequent segmentation of the objects under study. In this work, an objective segmentation is applied to compare the two PLA/clay microstructures. Then, relevant descriptors of the 3D microstructure (dimensions of the reconstructed objects, their specific surface area and orientation) are measured and used to quantitatively explain the effect of the clay particles on the thermal stability of the nanocomposites. The tortuous path has been calculated—based on the descriptors of the microsturecture—and proved to be larger for PLA/Cloisite 30B nanocomposite compared to that of PLA/Cloisite 20A. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 134, 44691.