double-strand polymer 

Also contains definitions of: ladder polymer, spiro polymer
https://doi.org/10.1351/goldbook.D01852
A polymer the macromolecules of which are double-strand macromolecules.
Notes:
  1. A polymer, the macromolecules of which are spiro macromolecules is termed a spiro polymer.
  2. A polymer, the macromolecules of which are ladder macromolecules is termed a ladder polymer.
Source:
PAC, 1996, 68, 2287. (Glossary of basic terms in polymer science (IUPAC Recommendations 1996)) on page 2304 [Terms] [Paper]