STUDY OF THE MORPHOLOGY, THERMAL, MECHANICAL AND BARRIER PROPERTIES OF IRRADIATED POLYPROPYLENE NANOCOMPOSITES

In the last decades, the use of polymers as food packaging materials has increased enormously due to their advantages over other traditional materials. 1 Polymer packaging provides many properties including strength and stiffness, barrier to oxygen and moisture. In order to ensure food safety, reduce post harvest losses and facilitate international trade, recently radiation technologies are always more often applied by the food industry, moreover it is a safe and environmentally clean and efficient technology. In the field of packaging, polypropylene (PP) films hold a prominent position because of their transparency, brilliance, low specific weight, chemical inertness and good processability. Unfortunately, PP, like other polyolefins, is characterized by low barrier properties, which results in poor protection of the packaged food. 2 To overcome this drawback the incorporations a few percent of commercial nanoparticles, in particular modified montmorillonite (MMT) in a polymeric matrix, can lead to several improvements like a decrease in the package permeability to gas and aroma, and an extended shelf life for the food. 3 The objective of this research was to study the changes of the structure and of the thermal, mechanical and barrier properties of PP/MMT films obtained by using a calandra machine, due to electron irradiation uses electrons accelerated in an electric field. The E-Beam had a fixed dose rate of approximately 103Gy/second.