A small region in a
macromolecule from which at least four
chains emanate, and formed by reactions involving sites or groups on existing macromolecules
or by interactions between existing macromolecules.
Notes:
- The small region may be an atom, a group of atoms, or a number of branch points connected
by bonds, groups of atoms, or oligomeric chains.
- In the majority of cases, a crosslink is a covalent structure but the term is also
used to describe sites of weaker chemical interactions, portions of crystallites,
and even physical entanglements.
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