(1. School of Materials Science and Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China) (2. School of Architecture, Xi’an University of Architecture and Technology, Xi’an 710055, China)
Building energy consumption is increasing with the growth demand for thermal comfort. At present, it has become the largest energy consuming industry in the world, and the research of thermal energy storage system is of great significance to promote more effective and environmentally friendly energy utilization. Paraffin-based phase change energy storage materials have become a research hotspot in building energy conservation because of its excellent thermophysical properties, such as high heat storage density, wide melting point range, good economic applicability and so on. However, the application of paraffin-based phase change materials in building materials is still limited due to the problems of easy leakage when solid-liquid phase change occurs and poor thermal conductivity. In recent years, researchers have been committed to the development of composite phase change materials with stable performance, high latent heat and excellent thermal conductivity, making them more promising in the field of construction. At present, the thermal conductivity of composite phase change materials can be greatly improved without leakage by compounding paraffin with different high thermal conductivity materials. The basic thermophysical properties of paraffin-based phase change materials are summarized, and the phase change temperatures of paraffin with different carbon atoms are introduced according to the chemical structure of paraffin. In addition, the phase change process of paraffin is described in detail, and the three ways of macro encapsulation, microcapsule encapsulation and porous material adsorption are mainly discussed for the leakage of paraffin. For the problem of poor thermal conductivity of paraffin, three ways of heat transfer enhancement are discussed, including adding high thermal conductivity materials, using different kinds of inorganic compounds wrapped and immersed in porous high thermal conductivity materials. This lays a foundation for the better application of paraffin-based phase change materials in building materials. In addition, the development prospect of paraffin-based phase change materials in architecture is prospected, and the research direction of paraffin-based phase change materials in architecture is pointed out, so as to provide reference for the preparation of new composite phase change materials suitable for large-scale application in architecture.