Quantitative High-Resolution Electron Microscopy (HREM) of defects in ordered polymers

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:468780

Wilson, P M ^[1]; Martin, D C ^[2]

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1. Foster-Miller, Inc., Waltham, MA (United States)
2. Univ. of Michigan, Ann Arbor, MI (United States)

Efforts in our laboratory and elsewhere have established the utility of low dose High Resolution Electron Microscopy (HREM) for imaging the microstructure of crystalline and liquid crystalline polymers. In a number polymer systems, direct imaging of the lattice spacings by HREM has provided information about the size, shape, and relative orientation of ordered domains in these materials. However, because of the extent of disorder typical in many polymer microstructures, and because of the sensitivity of most polymer materials to electron beam damage, there have been few studies where the contrast observed in HREM images has been analyzed in a quantitative fashion. Here, we discuss two instances where quantitative information about HREM images has been used to provide new insight about the organization of crystalline polymers in the solid-state. In the first, we study the distortion of the polymer lattice planes near the core of an edge dislocation and compare these results to theories of dislocations in anisotropic and liquid crystalline solids. In the second, we investigate in HREM contrast near the edge of wedge-shaped samples. The polymer used in this study was the diacetylene DCHD, which is stable to electron beam damage (Jc = 20 C/cm{sup 2}) and highly crystalline.

• OSTI ID: 468780
• Report Number(s): CONF-960877--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
CRYSTAL LATTICES
DISLOCATIONS
ELECTRON MICROSCOPY
MICROSTRUCTURE
POLYACETYLENES