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.
- 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.