Translational chain repeating unit

{
  "id": "MLC-T-CHM-013665",
  "term": "Translational chain repeating unit",
  "field": "Chemistry",
  "definition": "The shortest stretch of a polymer chain that, repeated by translation alone along the chain axis within the crystal lattice, regenerates the entire chain. For a helical chain it contains several constitutional repeating units, as in isotactic polypropylene, whose 3/1 helix repeats after three monomer units. It may differ between crystal polymorphs of the same polymer.",
  "synonyms": [
    "fiber repeat unit",
    "physical repeating unit"
  ],
  "subject": "Polymer",
  "see_also": [
    "crystal polymorph"
  ],
  "references": [
    "PAC, 2011, 83, 1831. 'Definitions of terms relating to crystalline polymers (IUPAC Recommendations 2011)' on page 1844 (https://doi.org/10.1351/PAC-REC-10-11-13)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/translational-chain-repeating-unit/"
}