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Segmental Relaxation in Crosslinked Rubber

Published online by Cambridge University Press:  10 February 2011

C. M. Roland
Affiliation:
Chemistry Division, Code 6120, Naval Researcah Laboratory, Washington, DC 20375-5342
C. A. Bero
Affiliation:
Chemistry Division, Code 6120, Naval Researcah Laboratory, Washington, DC 20375-5342
K. L. Ngai
Affiliation:
Electronics Science and Technology Division, Code 6807
M. Antonietti
Affiliation:
MPI fur kolloid und Grenzflachenforschung, Kantstr. 55, D 14513 Teltow, Germany
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Abstract

Studies of the local segmental relaxation in rubbery networks reveal a variety of behaviors. In experiments on networks with labeled junctions, whereby the motion of the crosslink site is specifically monitored, the segmental relaxation function broadens, accompanied by a larger activation energy, in a manner well-described by the coupling model of relaxation. The more usual experiment simply measures bulk relaxation, without discriminating among different relaxing entities. For networks, crosslinking introduces a distribution of relaxation behaviors, related to the proximity of a moiety to the junctions. The resulting inhomogeneously broadened relaxation function is difficult to analyze; nevertheless, a heightened sensitivity to temperature (larger activation energy) is exhibited, from which inferences can be made regarding the shape of the relaxation function. Finally, the segmental relaxation of highly crosslinked microgels is ostensibly homogeneous. Interestingly, however, the inverse correlation between the stretch exponent, β, and the activation energy, observed quantitatively in conventional networks, is violated by the microgels.

Type
Research Article
Copyright
Copyright © Materials Research Society 1996

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References

REFERENCES

1. Flory, P.J., Rubber Chem. Tech. 52, 1 (1979).Google Scholar
2. Erman, B. and Monnerie, L., Macromolecules 22, 3342 (1989).Google Scholar
3. Vilgis, T.A. and Boue, F.J., Poly. Sci. 26, 229 (1988).Google Scholar
4. Edwards, S.F., Polymer J. 17, 271 (1985).Google Scholar
5. Warner, M., J. Phys. C., 14, 4990 (1981).Google Scholar
6. Ngai, K.L., Rendell, R.W., Rajagopal, A.K. and Teitler, S., Ann. N.Y. Acad. Sci. 484, 150 (1986).Google Scholar
7. Ngai, K.L. and Roland, C.M., Macromolecules, 26, 6824 (1993).Google Scholar
8. Ngai, K.L. and Roland, C.M., Macromolecules, 27, 2454 (1994).Google Scholar
9. Roland, C.M. and Ngai, K.L., J. Chem. Physics, 103, 1152 (1995).Google Scholar
10. Roland, C.M., Ngai, K.L., and Lewis, L.J., J. Chem. Physics, 103, 4632 (1995).Google Scholar
11. Ngai, K.L. and Rendell, R.W., J. Non-Cryst. Solids, 131–133, 942 (1991).Google Scholar
12. Plazek, D.J. and Ngai, K.L., Macromolecules, 24, 1222 (1991).Google Scholar
13. Bohmer, R., Ngai, K.L., Angell, C.A., and Plazek, D.J., J. Chem. Phys. 99, 4201 (1993).Google Scholar
14. Shi, J.-F., Dickinson, L.C., MacKnight, W.J. and Chien, J.C.W., Macromolecules, 26, 5908 (1993).Google Scholar
15. Roland, C.M., Macromolecules, 27, 4242 (1994).Google Scholar
16. Angell, C.A., J. Non-Cryst. Solids 131–133, 13 (1991).Google Scholar
17. Roland, C.M. and Ngai, K.L., Macromolecules, 25, 5765 (1992).Google Scholar
18. Antonietti, M., Basten, R., and Lohmann, S., Macromol. Chem. Phys. 196, 441 (1995).Google Scholar
19. Antonietti, M., Pakula, T., and Bremser, W., Macromolecules 28, 4227 (1995).Google Scholar
20. Adolf, D.B. and Ediger, M.D., Macromolecules 25, 1074 (1992).Google Scholar
21. Bahar, I., Erman, B., Kremer, F., and Fischer, E.W., Macromolecules 25, 816 (1992).Google Scholar
22. Read, B.E., Poly. Eng. Sci. 23, 835 (1983).Google Scholar
23. Santangelo, P.G., Ngai, K.L., and Roland, C.M., Macromolecules 26, 2682 (1993).Google Scholar
24. Plazek, D.J., Chay, I.-C., Ngai, K.L., and Roland, C.M., Macromolecules, 28, 6432 (1995).Google Scholar
25. Flory, P.J. and Erman, B., Macromolecules, 15, 800 (1982).Google Scholar
26. Roland, C.M., Santangelo, P.G., Ngai, K.L., and Meier, G., Macromolecules 26, 6164 (1993).Google Scholar
27. Santangel, P.G., Ngai, K.L., and Roland, C.M., Macromolecules 27, 3859 (1994).Google Scholar
28. Roland, C.M., Macromolecules 28, 3463 (1995).Google Scholar
29. Ngai, K.L., Roland, C.M. and Yee, A.F., Rubber Chem. Tech., 66, 817 (1993).Google Scholar