<?xml version="1.0" encoding="UTF-8"?>
<term>
  <id>12799</id>
  <title>secondary relaxation peak</title>
  <longtitle>IUPAC Gold Book - secondary relaxation peak</longtitle>
  <doi>10.1351/goldbook.12799</doi>
  <code>12799</code>
  <status>current</status>
  <synonym><em>synonym</em>: secondary loss peak</synonym>
  <definitions>
    <item>
      <id>1</id>
      <text>Any peak in a loss curve either at a lower temperature than the temperature of the alpha relaxation peak or at a higher frequency than the frequency of the alpha relaxation peak.</text>
      <notes>
        <item>The use of the term "secondary relaxation transition peak" is discouraged.</item>
      </notes>
      <links>
        <item>
          <term>alpha relaxation peak</term>
          <url>https://goldbook.iupac.org//terms/view/12741</url>
        </item>
        <item>
          <term>beta relaxation peak</term>
          <url>https://goldbook.iupac.org//terms/view/12745</url>
        </item>
        <item>
          <term>gamma relaxation peak</term>
          <url>https://goldbook.iupac.org//terms/view/12772</url>
        </item>
        <item>
          <term>loss curve</term>
          <url>https://goldbook.iupac.org//terms/view/12781</url>
        </item>
      </links>
      <sources>
        <item>PAC, 2013, 85, 1017. 'Glossary of terms relating to thermal and thermomechanical properties of polymers (IUPAC Recommendations 2013)' on page 1038 (https://doi.org/10.1351/PAC-REC-12-03-02)</item>
      </sources>
    </item>
  </definitions>
  <altoutputs>
    <html>https://goldbook.iupac.org/terms/view/12799/html</html>
    <json>https://goldbook.iupac.org/terms/view/12799/json</json>
    <plain>https://goldbook.iupac.org/terms/view/12799/plain</plain>
  </altoutputs>
  <citation>Citation: 'secondary relaxation peak' 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.12799</citation>
  <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.</license>
  <collection>If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .</collection>
  <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.</disclaimer>
  <accessed>2026-06-04T10:47:04+00:00</accessed>
</term>
