Abstract
Self-supported thin spherulitic films of polyethylene change their form dramatically during observation in the transmission electron microscope. Crystalline diffraction contrast disappears, then details of the radiating fibrils become visible. The circumferential bands of a banded spherulite are originally visible in the diffraction contrast, and after this has faded they reappear with stronger contrast, but reversed. At the same time each spherulite in the originally flat specimen becomes conical in shape. The same topographical changes are observed in the scanning electron microscope.
All the effects can be explained by assuming that the crystalline sub-units of the spherulites deform in the electron beam in the same way as single crystals do. The anisotropic deformation of polyethylene single crystals in the electron microscope was described in Part 1 of this paper [1].
Similar content being viewed by others
References
D. T. Grubb, A. Keller, and G. W. Groves, J. Mater. Sci. 7 (1972) 131.
J. Dlugosz and A. Keller, J. Appl. Phys. 39 (1968) 5776.
A. Keller, J. Polymer Sci. 17 (1955) 291.
F. P. Price, ibid 37 (1959) 71.
H. D. Keith and F. J. Padden, ibid 39 (1959) 101.
A. Keller, ibid 39 (1959) 151.
A. Keller and D. C. Bassett, Proc. Roy. Microscopic Soc. 79 (1960) 243.
G. C. Claver, R. Buchdahl, and R. L. Miller, J. Polymer Sci. 20 (1956) 202.
P. H. Geil, “Polymer Single Crystals”, (Interscience, New York, 1963) p. 229
E. H. Andrews, M. W. Bennett, and A. Markham, J. Polymer Sci. A-2, 5 (1967) 1235.
H. D. Keith and F. J. Padden ibid 39 (1959) 123.
D. T. Grubb, J. Phys. E.: Sci. Instrum, 4 (1971) 222.
A. W. Agar, F. C. Frank, and A. Keller, Phil. Mag. 4 (1959) 32.
J. W. Heavens, A. Keller, J. M. Pope, and R. M. Rowell J. Mater. Sci. 5 (1970) 53.
A. Keller and S. Sawada, Makromolek. Chem. 74 (1964) 190.
J. Dlugosz, private communication.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Grubb, D.T., Keller, A. Origin of contrast effects in the electron microscopy of polymers. J Mater Sci 7, 822–835 (1972). https://doi.org/10.1007/BF00549911
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00549911