Environment-friendly refrigerant 'plastic crystal' is discovered, and may be used for air conditioners and refrigerators in the future



The University of Cambridge in the UK and the Catalan Institute of Technology in Spain have announced through joint research that they have discovered that ' plastic crystals ' of neopentyl glycol have very good properties as refrigerants. The previous refrigerant was gas, but the new material is solid, so it is difficult to be released into the air, and it is cheap and environmentally friendly.

Colossal barocalolic effects near room temperature in plastic crystals of neoopentglycol | Nature Communications

Green material for refrigeration identified | University of Cambridge

As fluorocarbon gas used as a refrigerant for refrigerators and air conditioners destroys the ozone layer, as of 2019, a gas called alternative fluorocarbons is used as a refrigerant. However, this alternative fluorocarbon also destroys the environment as a powerful greenhouse gas , so there has been a strong desire for the development of new materials as refrigerants.



Under these circumstances, Dr. Xavier Moya of Cambridge University and Dr. Jusepp Lwys Tamaritt of the Polytechnic Institute of Catalonia focused on plastic crystals as new materials to replace gas refrigerants. A plastic crystal is a substance that is in the middle state between liquid and solid because the constituent molecules are regularly arranged like a solid, but the molecules are disoriented as if it were liquid. Although liquid crystals are similar substances, in contrast to plastic crystals, molecules are disaggregated like liquid, while the orientation of molecules is aligned like solid.

by Pxhere

Dr. Moya et al. Measured the temperature change by applying pressure to plastic crystals of neopentyl glycol in the form of powder with a particle size of about 100 micrometers. Then, a temperature change comparable to that of the gas refrigerant used conventionally was found. The gas refrigerant is also cooled using the heat absorption and heat generation properties when it is compressed / expanded by pressurization / decompression, but the temperature of the flexible crystal changes based on a completely different principle. Plastic crystals are cooled using the 'barocaloric effect' (pressure heat effect) that causes pressure transition to cause phase transition by aligning the direction of the particles that make up the crystal under pressure. Also, not only pressure, but also electricity and magnetic force can generate the same effect.

Neopentyl glycol is widely used in the synthesis of paints and lubricants, and is a highly safe substance with low environmental impact. In addition, because it is solid rather than gas, recovery and management are relatively easy, and there is no concern about destroying the ozone layer or causing a greenhouse effect. Dr. Moya stated in the paper that 'one-fifth of the energy produced in the world is used for cooling such as air conditioning and refrigeration, but air conditioners and refrigerators that use gas refrigerants are not efficient.' Pointed out. It is hoped that the spread of solid refrigerant will establish more environmentally friendly cooling technology, and in the future we will work with the commercialization department of Cambridge University to aim for the commercialization of this new technology. is.

in Science, Posted by log1l_ks