Study and characterization of phase change material-recycled paperboard composite for thermoregulated packaging applications

Hot served food items are maintained around 60⁰C temperature. The food delivery system should be quick to transport such items. If these food items once prepared and stored in container equipped with phase change material (PCM) slabs with phase change temperature around serving temperature, it can maintain temperature of food item for longer time in food delivery process while utilizing lesser amount of energy. Beeswax is a bioderived PCM with phase change temperature around 60⁰C. Beeswax should be shape stabilized to serve thermoregulation purpose. This report has used recycled paperboard as matrix for shape stabilizing beeswax. Optimization study revealed that 45% is the maximum amount of beeswax that can be incorporated in paper composite. Beeswax showed melting enthalpy of 216.09 J/g and melting enthalpy of composite with beeswax content 45% was 102.51 J/g. The enthalpy of melting is directly proportional to amount of beeswax in composite. Thermal conductivity of beeswax and composite with 45% beeswax calculated with T-history method as 0.285 and 0.157 respectively. The carton containing PCM sheets maintain temperature at higher level for longer time than for carton without PCM. To address concerns such as toxicity, environment friendly nature and recycling, beeswax-recycled paperboard composite should be considered as promising candidate.