Pendant group

IUPAC definition
Pendant group
Side-group
An offshoot, neither oligomeric nor polymeric, from a chain.[1]

A pendant group (sometimes spelled pendent) or side group is a group of molecules attached to a backbone chain of a long molecule. Usually, this molecule would be a polymer. Pendant groups are different from pendant chains, as they are neither oligomeric nor polymeric.[2]

For example, the phenyl groups are the pendant groups on a polystyrene chain.

Large, bulky pendant groups such as adamantyl usually raise the glass transition temperature (Tg) of a polymer by preventing the chains from sliding past each other easily. Short alkyl pendant groups may lower the Tg by a lubricant effect.

References

  1. ↑ "Glossary of basic terms in polymer science (IUPAC Recommendations 1996)". Pure and Applied Chemistry. 68 (12): 2287–2311. 1996. doi:10.1351/pac199668122287.
  2. ↑ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version:  (2006–) "pendant group (side group)".


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