Properties and Phase Transitions in Polyphosphazenes.

Abstract

Polyphosphazenes were first synthesised towards the end of the last century. Now, a wide variety of polymers and copolymers with alkoxy, aryloxy and aminoxy groups have been synthesised. Recently, side chains have been connected directly to the backbone phosphorus modifying physical properties considerably. Variations in side group chemistry enables a wide span in properties to be covered ranging from glass temperatures approaching -100 C to melting points well above 300 C in some systems. Thermotropic behavior persists over a range of temperature. It was determined that degradation mechanisms were also important in determining thermal stability. For example, alkoxy phosphazenes degraded primarily via a chain unzipping process leaving little or no residue, whereas aryloxyphosphazenes mostly disintegrated through random chain scission (involving some chain transfer too) leaving a substantial residue.

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Document Details

Document Type
Technical Report
Publication Date
Jul 28, 1987
Accession Number
ADA183367

Entities

People

  • J. H. Magill

Organizations

  • University of Pittsburgh

Tags

DTIC Thesaurus Topics

  • Chemistry
  • Engineering
  • Heat Energy
  • Heat Transfer
  • Materials
  • Materials Science
  • Melting Point
  • Military Research
  • Phase
  • Phase Transformations
  • Physical Properties
  • Polymers
  • Scattering
  • Thermal Stability
  • Transitions
  • X Ray Scattering
  • X Rays

Readers

  • Materials Science and Engineering.
  • Organic Chemistry
  • Polymer Science and Engineering.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene