Aging

{
  "id": "MLC-T-CHM-000338",
  "term": "Aging",
  "field": "Chemistry",
  "definition": "Processes occurring in a polymeric material over a period of time that usually change its physical or chemical structure and so alter its properties. Chemical aging, driven by heat, light, oxygen or moisture, causes irreversible degradation such as embrittlement and discoloration, whereas physical aging is the slow structural relaxation of a glassy polymer toward equilibrium, which is erased when the sample is heated above its glass transition temperature.",
  "synonyms": [
    "ageing"
  ],
  "subject": "Polymer",
  "references": [
    "PAC, 1996, 68, 2313. 'Definitions of terms relating to degradation, aging, and related chemical transformations of polymers (IUPAC Recommendations 1996)' on page 2315 (https://doi.org/10.1351/pac199668122313)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/aging/"
}