GLOSSARY: Phase Change Materials (PCM)
Phase change materials (PCMs) act as a heat buffer when they absorb energy to convert from solid to liquid. They perform Intelligent phase change in temperature according to a desired range. How long they absorb heat for is dependent on the ambient temperature. This form of temperature control is used to regulate the storage temperature of medicines without the need for any power source. It has a reliable stability in thermal cycling. Challenges can be had in the pre-conditioning of the PCM to reach the required phase. Leak proof PCM packaging is a must, as this element is harder to contain than water base refrigerants.
Some PCMs can be free of hazard issues, however custom PCMs can be hazardous.