Ideal crystalline chain conformation

{
  "id": "MLC-T-CHM-005571",
  "term": "Ideal crystalline chain conformation",
  "field": "Chemistry",
  "definition": "The lowest-energy shape that a single, isolated polymer chain adopts when all its monomeric units are required to be geometrically equivalent, which approximates the chain shape found in the crystal. Packing can distort it when the crystal symmetry differs from the symmetry of the chain. The ideal conformation of isotactic polypropylene is a 3/1 helix, and that of polyethylene is an all-trans zigzag.",
  "subject": "Polymer",
  "see_also": [
    "crystal polymorph",
    "rod group"
  ],
  "references": [
    "PAC, 2011, 83, 1831. 'Definitions of terms relating to crystalline polymers (IUPAC Recommendations 2011)' on page 1841 (https://doi.org/10.1351/PAC-REC-10-11-13)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/ideal-crystalline-chain-conformation/"
}