Phase change materials in isothermal containers

Isothermal containers using phase change materials (PCMs) are used to transport temperature sensitive health products (medicines, vaccines, blood and its derivatives, biological samples, cells...). These standalone solutions are based on the thermal storage capacity of the PCM. Product requirements, logistical constraints and regulations are tightening, with stricter controls. Cold and cold/hot ambient temperature profiles are required for above-zero stringent temperature ranges like +2/+8 degrees C, +15/+25 degrees C and +32/+38 degrees C. Eutectic aqueous solutions and dry ice are not always suitable for these ranges. PCMs with above-zero melting temperatures (+5 degrees C, +20 degrees C and +35 degrees C) can meet these requirements. Organic and inorganic PCMs (like paraffins and salt hydrates) were tested in insulated boxes for various temperature ranges and various durations (up to 168 hours), under cold and hot ambient profiles. Compared to water-based solutions, they can cover different logistical constraints, but they have a reduced storage capacity and a high price.