LOW DENSITY POLYETHYLENE (LDPE) NANOCOMPOSITES WITH PASSIVE AND ACTIVE BARRIER PROPERTIES

Nanocomposites based on Low Density Polyethylene (LDPE) containing organically modified montmorillonite (OMMT) and polyethylene grafted with maleic anhydride (PE-g-MA) were obtained by the mixing molten state method at 130 degrees C (LDPE/PE-g-MA/Cv/OMMT). Furthermore, in order to obtain a material with active barrier properties, carvacrol (Cv) was incorporated into the nanocomposite (LDPE/PE-g-MA/Cv/OMMT). Carvacrol is an essential oil component with a high antimicrobial, antifungal, and antiparasitic capability. The nanocomposites were characterized by XRD, DSC, TGA, oxygen permeability, and tensile test. The nanocomposites without Cv (LDPE/PE-g-MA/OMMT) showed an intercalated morphology (confirmed by the X ray diffraction analysis), an improved percentage of crystallinity and a reduced permeability to oxygen (25%) as compared with LDPE. The rigidity of the resulting material correlated with the clay content as expected. The nanocomposite containing Cv (LDPE/PE-g-MA/Cv/OMMT) also show intercalated morphology with a greater displacement between the clay layers as compared with the nanocomposite without Cv produced by intercalation of the antimicrobial agent between the layers. The antimicrobial activity of (LDPE/PE-g-MA/Cv/OMMT) was observed by the reduction or inhibition on bacterial (Escherichia coli and Staphylococcus aureus) growth.