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Morphological changes of poly(tetrafluoroethylene) by heat treatment on NaCl

Published online by Cambridge University Press:  03 March 2011

Sadaatsu Yamaguchi
Affiliation:
Research & Development, Daikin Industries, Ltd., Settsu, Osaka-fu 566, Japan
Masaki Tsuji
Affiliation:
Laboratory of Polymer Condensed States, Institute for Chemical Research, Kyoto University, Uji, Kyoto-fu 611, Japan
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Abstract

Fine granules of poly(tetrafluoroethylene) (PTFE) were heat-treated/annealed on NaCl near its melting temperature (Tm) and/or at a temperature (Tc) between upper and lower feet of the exothermic peak in the DSC cooling process from Tm. Morphological changes of the granules were examined in the bright- and dark-field modes by transmission electron microscopy. When the granules were heat-treated near Tm, microfibrils of 20–30 nm in width and fibrils of 70–120 nm in width came out of the granules. The microfibrils were also observed in the fibrils. The microfibrils formed by heat treatment near Tm seemed to be identified as microfibrils of 20–30 nm in width which were recognized outside the granules annealed at Tc. It is expected that such a microfibril will grow to be a band in the band structure observed on the surface of bulk PTFE. Since the 0015 dark-field images showed that the PTFE chains in such microfibrils and fibrils are set perpendicular to their fibril axis, the chains should fold back and forth repeatedly at both lateral side-surfaces of the microfibrils and fibrils.

Type
Articles
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

1Takahashi, T., Teraoka, F., and Tsujimoto, I., J. Macromol. Sci. Phys. B12, 303 (1976).CrossRefGoogle Scholar
2Wittmann, J. C. and Smith, P., Nature 352, 414 (1991).CrossRefGoogle Scholar
3Yamaguchi, S. and Tsuji, M., Bull. Inst. Chem. Res., Kyoto Univ. 69, 127 (1991).Google Scholar
4Yamaguchi, S., unpublished data.Google Scholar
5Wunderlich, B., Macromolecular Physics (Academic Press, London, 1973), Vol. 1, pp. 275, 280.Google Scholar
6Hattori, Y., Asida, M., and Watanabe, T., Nippon Kagaku Kaishi 1975, 496 (1975).CrossRefGoogle Scholar
7Asida, M., Ueda, Y., and Watanabe, T., J. Polym. Sci., Polym. Phys. Ed. 16, 179 (1978).CrossRefGoogle Scholar
8Yamaguchi, S., Kobunshi Ronbunshu 39, 339 (1982).CrossRefGoogle Scholar
9Rahl, J., Evanco, A., Fredericks, J., and Reimschussel, C., J. Polym. Sci., Polym. Phys. Ed. 12, 2567 (1974).Google Scholar
10Yamaguchi, S. and Shimizu, T., Kobunshi Ronbunshu 39, 493 (1982).CrossRefGoogle Scholar
11Hasida, S., Hirakawa, S., and Namio, H., J. Appl. Polym. Sci. 32, 5685 (1986).CrossRefGoogle Scholar
12Yamaguchi, S., Kobunshi Ronbunshu 41, 407 (1984).CrossRefGoogle Scholar
13Wittmann, J. C. and Lotz, B., J. Polym. Sci., Polym. Phys. Ed. 23, 205 (1985).CrossRefGoogle Scholar
14Grebowicz, J., Pan, R., and Wunderlich, B., J. Appl. Polym. Sci. 38, 707 (1989).CrossRefGoogle Scholar
15Bunn, C. W., Cobbld, A. J., and Palmer, R. P., J. Polym. Sci. 28, 365 (1958).CrossRefGoogle Scholar