The absorption of phase change substances into commonly used building materials

The absorption of phase change substances into commonly used building materials was studied with the aid of a small series. The phase change materials comprised certain technical grades of carboxylic acids and polyalcohols. The specimens used in the absorption tests were prepared from ordinary Finnish building materials. The use of carboxylic acids makes it possible to achieve considerable increases in capacity. However, in order to prevent drainage or leakage, manufactured products must be coated in one way or another after absorption has occured. Porous wallboard exhibits a particularly strong increase in its storage capacity, and that of gypsum board also increases considerably.
Storage capacities achieved with polyalcohols such as neopentylglycol (NPG) were not as high as with carboxylic acids. The largest increase in storage capacity with NPG occured in the porous wallboard. Depending on the building material, more or less of the NPG evaporated with the water.