INCORPORATION OF PHASE CHANGE MATERIAL MICROCAPSULES IN PAPERBOARD FOR THE PREPARATION OF COLD STORAGE PACKAGING WITH IMPROVED THERMAL PROPERTIES

Packaging materials play an important role with regard to the thermal protection of temperature sensitive products [1]: preparation of innovative materials, with improved thermal properties, is hence of valuable industrial interest. In order to reduce the thermal effects caused by temporary heat spikes during goods logistic, packaging should possess a significant activity as thermal buffer. This property can be obtained by using Phase Change Materials (PCM), that undergo a phase change, e.g. from solid to liquid state, at a specific temperature (or in a narrow range of temperatures) near the envisaged application. Due to their latent heat, energy is stored during melting and recovered during freezing. For this reason, if a PCM is incorporated into the packaging material, it increases the thermal energy storage capacity of the container, hence buffering temperature oscillations. A large number of PCMs, having different physical and chemical characteristics, is nowadays available with the possibility of covering a wide range of temperatures and a multitude of practical situations. Microencapsulated PCM having paraffins as latent heat storage media (with melting temperatures around 0 °C) and blended with different supporting material for their stabilization are particularly suitable for the preparation of materials useful for the cold storage packaging. Very recently we described a simple method for the preparation of paperboard-PCM composites, pointing out their significant thermal buffering activity against environmental temperature oscillations [2]. In this presentation we summarize the main aspects of our recent research activity in this field.