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 @O04286@ 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.
Source:
PAC, 1996, 68, 2287. 'Glossary of basic terms in polymer science (IUPAC Recommendations 1996)' on page 2298 (https://doi.org/10.1351/pac199668122287)