Cerdanyola del Vallès, 12th July 2019. Most of the refrigerators and air conditioners use hydrofluorocarbons (HFCs) and hydrocarbons (HC), which are highly toxic and flammable and contribute to global warming when they reach the atmosphere. When pressure is applied, plastic crystal neopentylglycol (NPG) has shown an outstanding cooling effect, similar to the recently mentioned gases. NPG is a well-known material, widely used in the synthesis of paints, polyesters and lubricants. In addition, this material is cheap, easy to obtain and works practically at room temperature.
The research, carried out by a team from the Universitat Politècnica de Catalunya, the University of Cambridge, the Université de Bordeaux and the University of Barcelona, in collaboration with the ALBA Synchrotron, describes the thermal changes that take place when applying pressure to the plastic crystals.
Measurements were done at the Materials Science and Powder Diffraction (MSPD) beamline of the ALBA Synchrotron. There, researchers were able to identify how the crystal structure of NPG changed when heating the sample. They perform high-pressure X-ray diffraction analysis at room temperature and relatively high temperature (up to 400 K) to unveil the structural phase diagram of NPG.
These results pave the way for using this material as al alternative eco-friendly solution for cooling systems. This is why researchers participating in the study have registered a joint patent to bring to the market this material.
Fig. Detail of all X-ray diffraction pattern obtained in diamond anvil cell at 0.45 GPa and 321 K, at the MSPD beamline of the ALBA Synchrotron.
