Non-crystalline polymer networks, whether swollen or not, may exhibit interchain structuring effects due to incompatibility of various parts of the chains (e.g., backbone-side chain or blocks along a copolymer chain). Also, the network-formation process may lead to inhomogeneously crosslinked networks, possibly resulting in micro-phase separation. The complete polarized light scattering envelope provides structural information on the basis of the Rayleigh-Debye approximation in terms of either correlation functions or specific models for the structure. Small angle data can be utilized in conjunction with Gaussian correlation functions to obtain the scattered intensity at zero angle. This quantity yields the extent of polarizability fluctuations — sometimes relatable to fluctuations in crosslink density — as well as the mean anisotropy per volume element — sometimes relatable to regions of mesomorphic order. Wide angle data may reveal the existence of a more specific structure than that implied by Gaussian correlation functions. A comparison of the experimental data with calculated scattering patterns for specific models of the structure then becomes useful. Recent studies on various networks (poly saccharides, gelatin, poly vinylalcohol, hydrophilic poly methacrylates and poly urethanes) will be used to illustrate the above concepts.
KeywordsLight Scattering Polymer Network Crosslinking Density Urethane Link Rayleigh Ratio
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- 1.D. McIntyre and F. Gornick “Light Scattering from Dilute Polymer Solutions”. Gordon and Breach, N. Y., 1964Google Scholar
- M. Kerker, “The Scattering of Light”, Academic Press, N. Y., 1969.Google Scholar
- 3.J. Polymer Sci. Part C, 5 (1964)Google Scholar
- J. Polymer Sci. Part C, 13 (1966)Google Scholar
- R. S. Stein in. Stein in “Electromagnetic Scattering”, Proceedings of the Second Interdisciplinary Conference on Electromagnetic Scattering, R. L. Rowell and R. S. Stein eds., Gordon and Breach Publ., N. Y., 1967.Google Scholar
- 4.Reviewed in K. Dubek and W. Prins, Fortschr. Hochpolym. Forsch., 6, 1 (1969).Google Scholar
- 6.J. H. Gouda and W. Prins, J. Polymer Sci. Part A2, in press. See also ref. 18.Google Scholar
- 10.J. J. van Aartsen, These proceedings.Google Scholar
- 12.M. Ilaysk,y and W. Prins, Macromolecules, 1970, in press.Google Scholar
- 14.R. S. Stein, J. Polymer Sci., Part B, 7, 637 (1969).Google Scholar
- 18.J. H. Gouda, Ph.D. Thesis, Technological University, Delft, 1969, The Netherlands, available upon request until supply is exhausted.Google Scholar
- 20.R. Blokland, “Elasticity and Structure of Polyurethane Networks”, Available through Gordon and breach, N. Y., 1969.Google Scholar