{"term":{"id":"08795","title":"electret","longtitle":"IUPAC Gold Book - electret","doi":"10.1351\/goldbook.08795","code":"08795","status":"current","definitions":[{"id":1,"text":"Dielectric material with a permanent or quasi-permanent electric dipole.","notes":{"1":"A real-charge electret is obtained by the charge carrier injection onto the surface or into a parent dielectric material. It may contain either positive or negative excess charges or both, which must be trapped so that a good insulating parent dielectric material such as a fluoropolymer must be used.","2":"An oriented-dipole electret is obtained by poling a parent dielectric material with dipolar groups at a temperature above the glass transition temperature \\(T_{\\rm{g}}\\), and eventual next stabilization of the structure by cooling the electret down below \\(T_{\\rm{g}}\\) or by crosslinking.","3":"Electrets are electric equivalents of magnets; electric magnets. Some oriented-dipole electrets are ferroelectric polymers and piezoelectric polymers. Quartz is an example of the natural electret."},"links":[{"term":"charge carrier","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/08775"},{"term":"dielectric material","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/08790"},{"term":"poling","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/08857"}],"sources":["PAC, 2022, 94, 15. 'Glossary of terms relating to electronic, photonic and magnetic properties of polymers (IUPAC Recommendations 2021)' on page 25 (https:\/\/doi.org\/10.1515\/pac-2020-0501)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/08795\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/08795\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/08795\/plain"},"citation":"Citation: 'electret' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351\/goldbook.08795","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-07-13T08:07:21+00:00"}}