The Flexibility of Various Molecular Swivels Used to Control the Rigidity and Tractability of Aromatic Heterocyclic Polymers

William Welsh, D. Bhaumik, J. E. Mark

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Some aromatic heterocyclic polymers are rigid or rodlike and form liquid-crystalline phases which can be used to prepare films and fibers having unusual strength and thermal stability. They are, however, very nearly intractable unless some atoms or groups of high flexibility are introduced along the chains. The present theoretical investigation employs semiempirical methods to calculate intramolecular energies of various conformations about such “molecular swivels” in order to characterize their flexibility. In addition, simple geometric arguments are used to determine which swivels have one or more conformations exhibiting the parallel or collinear chain continuation which is characteristic of liquid-crystalline phases and apparently essential to the unusual mechanical properties of these materials.

Original languageEnglish (US)
Pages (from-to)59-84
Number of pages26
JournalJournal of Macromolecular Science, Part B
Volume20
Issue number1
DOIs
StatePublished - Aug 1 1981

Fingerprint

swivels
Aromatic polymers
rigidity
Rigidity
Conformations
flexibility
Crystalline materials
polymers
Liquids
liquids
Thermodynamic stability
thermal stability
mechanical properties
Atoms
Mechanical properties
fibers
Fibers
atoms
energy

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Condensed Matter Physics
  • Polymers and Plastics
  • Materials Chemistry

Cite this

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The Flexibility of Various Molecular Swivels Used to Control the Rigidity and Tractability of Aromatic Heterocyclic Polymers. / Welsh, William; Bhaumik, D.; Mark, J. E.

In: Journal of Macromolecular Science, Part B, Vol. 20, No. 1, 01.08.1981, p. 59-84.

Research output: Contribution to journalArticle

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