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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.

Sodium montmorillonite was incorporated into a poly(epsilon-caprolactone)-starch blend by means of a ball mill. The structural organization and physical (mechanical, thermal and barrier) properties were analyzed and correlated with the milling conditions. Scanning electron microscopy and X-ray characterization show that the milling process can improve the compatibilization between the PCL and the starch phases, while promotes the dispersion of clay minerals at nanometric level. The milling time strongly influences the mechanical and barrier properties. In particular, the best results in terms of elastic modulus and permeability coefficient were achieved with a complete delamination of the pristine clay structure. In summary, the milling process not only has demonstrated to be a promising compatibilization method for immiscible PCL-starch blends, but it can be also used to improve the dispersion of nanoparticles into the polymer blends. (C) 2008 Elsevier Ltd. All rights reserved.

This paper reports the preparation and characterization of green composites based on pectins and nano-hybrids composed of halloysite nanotubes (HNTs) loaded with rosemary essential oil. Different hybrid percentages were mixed into a pectin matrix, by ball milling in the presence of water. Cast films were obtained and analyzed. Structural organization and physical properties (thermal, mechanical, barrier to water vapor) were correlated to the nano-hybrid content. A preliminary study on the kinetics of release of the rosmarinic acid, chosen as a model molecule, was also performed. This work showed the potential of these systems in the active packaging field where controlled release of active species is required.