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Structural Changes in Glassy Polycarbonate Due to Cyclic Loading

Published online by Cambridge University Press:  16 February 2011

Liang Bao Liu ,
Albert F. Yee ,
John C. Lewis ,
Xiaowei Li  and
David W. Gidley
Liang Bao Liu
Affiliation:
Dept. of Materials Science and Engineering
Albert F. Yee
Affiliation:
Dept. of Materials Science and Engineering
John C. Lewis
Affiliation:
Dept. of Materials Science and Engineering
Xiaowei Li
Affiliation:
Dept. of Materials Science and Engineering
David W. Gidley
Affiliation:
Dept. of Physics The University of Michigan, Ann Arbor, MI 48109-2136
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Abstract

Glassy polycarbonate was subjected to cyclic stresses and the changes in its structure were studied by DSC, positronium annihilation lifetime spectroscopy (PALS), and small and medium angle X-ray scattering. Upon increased exposure to cyclic loading, the enthalpy overshoot near Tg increased in a manner similar to increasing physical aging. However, the “hole” size as revealed by PALS increased, unlike physical aging. SAXS reveals an increase in the short range order and the amplitude of density fluctuation. These results can be explained in a consistent manner. We conclude that mechanical loading does cause changes in the glassy structure.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 215: Symposium R2 – Structure, Relaxation and Physical Aging of Glassy Polymers , 1990 , 61
Copyright
Copyright © Materials Research Society 1991

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References

1. Struik, L.C.E., Physical Aging in Amorphous Polymers and Other Materials. Elsevier Scientific, New York (1978).Google Scholar
2. Stemstein, S.S., Myers, F.A., and Cama, F.C., Ann. NY Acad. Sci., 227, 94–99 (1977).Google Scholar
3. Struik, L.C.E., Polymer, 21, 962–967(1980).Google Scholar
4. Smith, T.L., Ricco, T., Levita, G., and Moongan, W.K., Plast. Rub. Proc. App., 6, 81–84(1985).Google Scholar
5. Bauwens-Crowet, C. and Bauwens, J.C., Polymer, 28, 1863–1868(1987).Google Scholar
6. McKenna, G.B. and Lee, A., Polym. Eng. and Sci., 30, 431–435(1990).Google Scholar
7. Takemori, M. T., Adv. Polym. Sci. 91/92, 263–299(1990)Google Scholar
8. Kobayashi, Y., Zheng, W., Meyer, E.F., McGervey, J.D., Jamieson, A.M., and Simha, R., Macromol., 22, 2302–2306 (1989).Google Scholar
9. Hill, A.J. and Agrawal, C.M., J. of Polym. Sci. Part B: Polym. Phy., 28, 387–405(1990).Google Scholar
10. Song, H.H., PhD thesis, University of Cincinnati, 1989.Google Scholar
11. Liu, L.B., Yee, A.F. and Gidley, D.W., ”Effect of Cyclic Stress on Enthalpy Relaxation in Polycarbonate”, submitted to J. Polym. Sci. Polym. Phys. Ed. for publication.Google Scholar
12. Liu, L.B., Gidley, D.W. and Yee, A.F., ”Effect of Cyclic Stress on Structural Changes in Polycarbonate as Probed by Positronium Annihilation Lifetime Spectroscopy”, submitted to J. Polym. Sci. Polym. Phys. Ed. for publication.Google Scholar
13. Liu, L.B., Yee, A.F., Lewis, J.C., and Gidley, D.W., ”Structural Changes in Glassy Polycarbonate Induced by Cyclic Stresses”, manuscript accepted for publication by J. Non-Crystalline Solids.Google Scholar