Chain-orientational disorder

{
  "id": "MLC-T-CHM-001856",
  "term": "Chain-orientational disorder",
  "field": "Chemistry",
  "definition": "A structural disorder in polymer crystals in which chemically identical chains running in opposite directions along their axis, up and down, share the same lattice in a statistical mixture. It arises when both orientations pack with nearly the same energy, so no long-range order of directions develops. The disordered alpha form of isotactic polypropylene is a typical example.",
  "subject": "Polymer",
  "see_also": [
    "structural disorder"
  ],
  "references": [
    "Purple Book, 1st ed., p. 80 (http://old.iupac.org/publications/books/author/metanomski.html)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/chain-orientational-disorder/"
}