Side groups
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.
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.
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