In this work, an innovative approach to overcome the issue of the poor thermo-oxidative stability of polymer/clay nanocomposites is proposed. Specifically, biodegradable polylactic acid (PLA)-based nanocomposites, containing organo-modified clay with in-built antioxidant activity, were prepared. Through a two-step chemical protocol, a hindered phenol antioxidant was chemically linked to the ammonium quaternary salt which was then intercalated between the clay platelets [(AO)OM-Mt]. The nanocomposites were characterized and their thermo-oxidative stability during melt processing and under long-term thermal test conditions was investigated. PLA nanocomposites containing the (AO)OM-Mt showed higher oxidative stability, along with better clay dispersion, compared to PLA-nanocomposites containing commercial clay and a free hindered phenol antioxidant. Obtained results can be explained considering that (AO)OM-Mt may act locally, at the interface, between the silicate layers and the polymer macromolecules, thus contributing to the observed improved stability of the polymer both during processing and under long-term thermal-oxidative conditions.
Bibliographical noteThis is the peer reviewed version of the following article: Dintcheva, N. T., Al-Malaika, S., Morici, E., & Arrigo, R. (2017). Thermo-oxidative stabilization of polylactic acid-based nanocomposites through the incorporation of clay with in-built antioxidant activity. Journal of Applied Polymer Science, Early view., which has been published in final form at http://dx.doi.org/10.1002/app.44974. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
- bio-based nanocomposites
- polylactic acid
- thermo-oxidative stability