A highly ramified macromolecule
essentially each constitutional unit
is connected to each other constitutional unit
and to the macroscopic phase boundary by many permanent paths through
the macromolecule, the number of such paths increasing with the
average number of intervening bonds; the paths must on the average be
co-extensive with the macromolecule.
Usually, and in all
systems that exhibit rubber elasticity, the number of distinct paths
is very high, but, in most cases, some constitutional units exist
which are connected by a single path only.
If the permanent paths
through the structure of a network are all formed by covalent bonds,
the term covalent network may be used.
physical network may be used if the permanent
paths through the structure of a network are not all formed by
covalent bonds but, at least in part, by physical interactions, such
that removal of the interactions leaves individual macromolecules or
a macromolecule that is not a
PAC, 1996, 68, 2287
(Glossary of basic terms in polymer science (IUPAC Recommendations 1996))
on page 2298
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