Development of Double‐Layered PE/PCL Films for Food Packaging Modified with Zeolite and Magnetite Nanoparticles

Low‐density polyethylene is a classic material used for food packaging due to its numerous advantages, but low oxygen barrier property is its main weakness. To improve permeability properties, double‐layered polyethylene/polycaprolactone (PE/PCL) films were prepared with the addition of zeolite or/and magnetite in PCL layer. Zeolite and magnetite nanoparticles were added as the modifiers in PCL film, as they slow down the process of oxygen permeability. For the multicomponent materials of great importance is matrix‐filler interaction that result in better dispersion of particles in the matrix and greater adhesion. The consequence of nanoparticle usage is development of new formulation strategies for composites which have potential applications in various types of packaging (dried food, frozen food, etc.). Particularly important for the double‐layered films is good adhesion between two layeres of films as they can easily separate under the mechanical stress. Food packaging, except good barrier, is needed to have good thermal and mechanical properties because they have to be flexible and endure the higher temperatures, like sterilization, etc. For the studied samples, oxygen permeability parameters were analyzed but also thermal and mechanical properties were determined. It is found that thermal stability and mechanical properties of double‐layered films compared to PE film alone were improved, especially for the samples when zeolite is modified with magnetite. Oxygen barrier performance in modified PE/PCL samples was improved, as it can be seen in sample with higher content of magnetite in zeolite.