Phosphonium ionic liquid as interfacial agent of layered double hydroxide: Application to a pectin matrix

Phosphonium ionic liquid (IL) combined with 2-ethylhexanoate counter anion has been used as interfacial agent of layered double hydroxide (LDH). First, the intercalation of hexanoate anion between the LDH layers was confirmed by thermogravimetric analysis (TGA) and X-ray diffraction (XRD). Then, this thermally stable organophilic LDH was introduced at different amount (1, 3 and 5 wt%) into pectin matrix leading to an increase of the thermal stability of the resulting nanocomposites (+35-40 °C). In addition, the good distribution of the modified LDH led to an increase of the mechanical performances through the elastic moduli (+60%) as well as a significant increase of the water barrier properties of two orders of magnitude for the pectin containing 5 wt% of LDH-Ionic Liquid.