double-strand chain

in polymers
https://doi.org/10.1351/goldbook.D01849
A @[email protected] that comprises @[email protected] connected in such a way that adjacent constitutional units are joined to each other through three or four atoms, two on one side and either one or two on the other side of each @[email protected]
Source:
PAC, 1996, 68, 2287. (Glossary of basic terms in polymer science (IUPAC Recommendations 1996)) on page 2294 [Terms] [Paper]