“Defective” DuPont Liquid Crystalline Polyester

H. Ade et al. with B. Wood and I. Plotzker (DuPont)

  • Samples: Commercial and pre-commercial Liquid Crystalline Polyester polymerized from several monomers, all rich in aromatic and carbonyl functionality
  • Issue/Problem: Two different processing routes of material with the same nominal composition yield different mechanical characteristics.
  • Material with preferred properties costs more to produce. 
  • Traditional characterization techniques failed to clearly distinguish these materials.
  • X-ray microscopy demonstrated presence of four chemically distinct phases in ‘cheap’ material, while ‘expensive’ material did not exhibit phase separation.
  •  
    X-ray micrographs of “defective” material acquired at two photon energies
     
     
    E(ph)=285.0 eV E(ph)= 286.75 eV
     
     
    Emphasizes aromatics: Small round and continuous, aromatic rich phases are visible Relative contrast change & reversal: This & images not shown confirm phase separation into four phases

    H. Ade et al.,  Mater. Res. Soc. Symp. Proc. 437, 99 (1996)
    Copywrite 1996 H. Ade. Do not reproduce without the permission of H. Ade (single print-out excepted)
    Return to [STXM Science]  [STXM Research Group]

    Stephen Urquhart  urquhart@unity.ncsu.edu September 13, 1998