External fluctuations of temperature and relative humidity due to the day/night and winter/summer alternations are considered as a greats important factors affecting the living surrounding environment.
Heating, ventilation and air conditioning (HVAC) system used to control the temperature and the relative humidity of indoor environment of building envelope is responsible of 45% of the world’s total energy consumption 1, 2, 3. For this matter, several methods have been developed to decrease using HVAC system and increase the comfort level of living environment, while innovative passive materials are introduced as the best solution to decrease energy consumption 2, 4, 5. Thermal storage materials as PCM’s are developed to stabilize the indoor temperature by absorbing and releasing a large amounts of energy 6,7 , while humidity control materials (HCM’s) are developed to stabilize the indoor relative humidity by absorbing and releasing moisture 8, 9. Recently, phase change humidity control materials (PCHCM) are developed by integration of microencapsulation materials (MPCM) in porous materials in order to provide indoor thermal and humid buffering capacity 10, 11.