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Light Scattering Studies of the State of Dispersion in Molecular Composites

Published online by Cambridge University Press:  21 February 2011

Benjamin S. Hsiao
Affiliation:
Polymer Research Institute, University of Massachusetts, Amherst, MA 01003
Richard S. Stein
Affiliation:
Russell Gaudiana and Norman Weeks, Polaroid Corporation, Cambridge, MA 02139
Silvie Cohen Addad
Affiliation:
Russell Gaudiana and Norman Weeks, Polaroid Corporation, Cambridge, MA 02139
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Abstract

Polymer solutions comprising stiff-chain polyester and flexible polysulfone were examined via light scattering techniques. Results were analyzed using the Stein-Wilson extension of the Debye-Bueche theory, in which the correlation lengths due to orientation fluctuations and mean-squared fluctuations of the molecular anisotropy were obtained. For a molecular dispersion, the correlation length is small and a function of concentration; as the anisotropy is attributed to the rod molecules. Aggregation of rods is associated with an increase in the magnitude and size of the density fluctuations, and a change in anisotropy fluctuations is dependent on the degree of orientation correlation of the rods in the aggregate. Blends prepared by solution casting were studied by a small-angle light scattering method. Results thus far demonstrate that aggregates are present in most of the rod/coil composites prepared.

Type
Research Article
Copyright
Copyright © Materials Research Society 1990

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References

REFERENCES

1. Onsager, L., Ann. N.Y. Acad. Sci., 51, 627 (1949).Google Scholar
2. Flory, P. J., Macromolecules, 11, 1119 (1978).Google Scholar
3. Wang, C. P., Ohnuma, H. and Berry, G., J. Polym. Sci. Polym. Symp., 65, 173 (1978).Google Scholar
4. Ying, Q., Chu, B., Qian, R., Bao, J., Zhang, J. and Xu, C., Polymer, 26, 1401 (1985).Google Scholar
5. Ying, Q. and Chu, B., Macromolecules, 20, 871 (1987).Google Scholar
6. Stein, R. S. and Wilson, P. R., J. Appl. Phys., 33(6), 1914 (1962).Google Scholar
7. Debye, P. and Bueche, A., J. Appl. Phys., 20, 518 (1940).Google Scholar
8. Stein, R. S. and Stidham, S. N., J. Appl. Phys., 35(1), 42 (1964).Google Scholar
9. Sinta, R., Gaudiana, R. A., Minns, R. and Rogers, H. G., Macromolecules, 20, 2374 (1987).Google Scholar
10. Kaye, W. and McDaniel, J. B., Appl. Optics, 13(8), 1934 (1974).Google Scholar
11. Brookhaven Instrum. Corp., Instruction Manual For Laser Light Scattering Goniometer, 1985.Google Scholar
12. Taber, R. J., Stein, R. S. and Long, M. B., J. Polym. Sci. Polym. Phys., 20, 2041 (1982).Google Scholar
13. Rojstaczer, S. and Stein, R. S., Mol. Cryst. Liq. Cryst., 157, 293 (1988).Google Scholar
14. Koberstein, J., Russell, T. P. and Stein, R. S., J. Polym. Sci. Polym. Phys., 17, 1719 (1979).Google Scholar