Enhanced mechanical and gas barrier properties of poly(ε-caprolactone) nanocomposites filled with tannic acid-Fe(III) functionalized high aspect ratio layered double hydroxides

Inspired by versatile adhesive ability of mussel adhesion proteins, tannic acid-Fe(III) functionalized high aspect ratio layered double hydroxides (LDHs@TA-Fe(III)) was firstly prepared via a facile and fast deposition of one-step assembled TA-Fe(III) coatings on the surface of layered clay. LDHs@TA-Fe(III)/poly (epsilon-caprolactone) (PCL) nanocomposites were prepared by blending LDH@TA-Fe(III) and pure PCL via solution casting method to obtain homogeneous films. The results of thermal analysis confirm that LDHs@TA-Fe(III) can act as a nucleating agent. It is revealed that the inclusion of LDHs@TA-Fe(III) up to an appropriate level of content resulted in a remarkable enhancement in the mechanical and gas barrier properties. However, excess LDHs@TA-Fe(III) loadings give rise to a decrease in the mechanical properties. With incorporation of only 1 wt% LDHs@TA-Fe(III), a 47% increase in elongation at break and 21% reduction in the oxygen relative permeability are achieved. The reinforcement effect brought by LDHs@TA-Fe(III) is fairly noteworthy at low clay loadings potentially owing to the strong interfacial interactions between the clay and matrix. (C) 2018 Elsevier B.V. All rights reserved.