Reaction involving sites or groups on existing macromolecules or an
interaction between existing macromolecules that results in the formation
of a small region in a macromolecule from which at least four chains emanate.
- 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.
- A reaction of a reactive chain end of a linear
macromolecule with an internal reactive site of another linear macromolecule
results in the formation of a branch point, but is not regarded as a crosslinking reaction.
PAC, 2007, 79, 1801
(Definitions of terms relating to the structure and processing of sols, gels, networks, and inorganic-organic hybrid materials (IUPAC Recommendations 2007))
on page 1821
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook