How to Make Paraffin Phase Change Building Material
The paraffin phase change temperature can be adjusted by using its components to select linear paraffins with a small number of carbon atoms, such as: hexadecane, heptadecane, octadecane, eicosane, and 30 #paraffin and 46 #paraffin wax. Its melting point is controlled at 20 ~ 30 °C, which can be used as raw material for building materials.
Paraffin phase change heat storage materials can only be combined with building materials to facilitate the formation of structurally integrated components with excellent performance. The current combined methods mainly include direct addition, soak adsorption and encapsulation method.
The direct addition method is to mix liquid or powdered phase change materials directly with building materials (such as gypsum powder, cement) to form gypsum board or cement board with energy storage function. Direct addition method is convenient to control the amount of addition, but it is easy to generate phase separation and leakage.
The soaking adsorption method is to soak a building material (gypsum, expansive clay, porous concrete) having large volume and microporous structure into a molten phase change material, and suck the liquid phase change heat storage material through the capillary force of the micropores. So that no liquid leakage occurs when solid-liquid phase changes occur.
Encapsulation method includes large volume sealing and micro volume encapsulation. Large-volume sealing is to put the phase change material into bags or tube containers. It is widely used in the field of solar energy. However, due to its too small contact area with the environment during phase change, the energy transfer efficiency is not high, which limits its application.
Micro-volume encapsulation is now a hot topic at home and abroad. Micro-volume encapsulation mainly refers to microcapsule technology. It makes use of certain inorganic or organic polymer compounds to enwrap phase change paraffin wax by physical or chemical method.