Processes that occur in a polymeric
material during a specified period
of time, and that usually result in changes in physical and/or chemical
structure and the values of the properties of the material.
PAC, 1996, 68, 2313
(Definitions of terms relating to degradation, aging, and related chemical transformations of polymers (IUPAC Recommendations 1996))
on page 2315
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A.Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook