Heat-resistant fully bio-based nanocomposite blends based on poly(lactic acid)

Poly(lactic acid) (PLA) is melt mixed with polyamide 11 (PA11) to obtain a heat-resistant fully bio-based blend with PLA as the dominant component. The goal is achieved by adding small amounts of organoclay (OMMT), which is used to manipulate the blend microstructure. The selective positioning of the OMMT inside the PA11 and at the PLA/PA11 interface turns the blend morphology from drop/matrix into co-continuous at high PLA content (70 wt%). The OMMT-rich PA11 framework that interpenetrates the major PLA phase effectively contributes to bear stresses, and the nanocomposite blend keeps its structural integrity up to ?160 °C, i.e., about 100 °C above the PLA glass transition. Combining a judicial selection of the blend constituents and a clever manipulation of the blend microstructure through the addition of nanoparticles, an "engineered" fully bio-based nanocomposite blend with PLA as the dominant component is obtained that is able to retain its structural integrity up to ?160 °C. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.