Microencapsulated phase change material (microPCM) products are very small bi-component particles consisting of a core material—the PCM – and an outer shell or capsule wall. The PCM substance is typically a paraffin-wax or a fatty acid ester which absorbs and releases heat in order to maintain a particular temperature. For example, if the microPCM were used in a ski jacket, the PCM would initially absorb the skier's body heat (the PCM melts inside the capsule wall) and store it until the body temperature drops from the outside environment; at which time, the heat is released (the PCM re-solidifying within the capsule wall) giving warmth to the skier and keeping the temperature regulated for his/her comfort. Throughout this process the capsule wall contains the PCM, so regardless of whether the PCM is in the liquid or solid state, the capsule itself remains as a solid particle containing the PCM. The capsule wall is an inert, very stable polymer.
The microPCM product has the following general properties: