Use of phase change materials to develop electrospun coatings of interest in food packaging applications

In the present study, a heat management PS foam tray containing an ultrathin fiber-structured PS/PCM coating was prepared by using high throughput electrohydrodynamic processing. To this end, polystyrene (PS) was used as the encapsulating matrix of a commercial phase change material (PCM) called RT5 (a blend of paraffins with a transition temperature at 5 °C), by using the electrospinning technique. With the aim of imparting heat management capacity to the trays, the PS tray was coated by the PS/PCM ultrathin fiber mats and a soft heat treatment was applied to improve the adhesion between the layers. Results showed that RT5 could be properly encapsulated inside the PS matrix, with a good encapsulation efficiency (ca. 78%) and the developed PS fibers had a heat storage capacity equivalent to ∼34 wt.% of the neat PCM. The effect of storage time and temperature was evaluated on the heat storage capacity of the developed PS-trays with the ultrathin fiber-structured PS/PCM layer. The heat storage capacity was affected not only by the storage time, but also by the temperature. This work adds a new insight on the development of heat management polymeric materials of interest in food packaging applications, in order to preserve the quality of refrigerated packaged food products. Although the electrohydrodynamic processing seems to be a promising alternative to develop heat management materials, further works will be focused on the improvement of heat storage capacity and efficiency of the developed packaging materials along storage time.