Summary
It has recently been reported (6, 7) that poly(methyl methacrylate) particles that are sterically stabilised by polydimethylsiloxane flocculate on cooling when dispersed in short chain n-alkanes. Since the LCFT was reported to be essentially independent of the nature of the dispersion medium, it was postulated (2) that incipient flocculation of these particles was caused by crystallisation of the polydimethysiloxane chains, which would have allowed the attractive van der Waals forces to become operative. This hypothesis has now been confirmed by low temperature X-ray studies.
Zusammenfassung
Von (6, 7) wurde kürzlich mitgeteilt, daß Poly(methylmethacrylat)-Teilchen, die mit Polydimethylsiloxan sterisch stabilisiert sind, in kurzkettigenn-Alkanen als Dispersionsmittel ausflocken. Da die LCFT im wesentlichen unabhängig von der Natur des Dispersionsmediums ist, wurde von (2) angenommen, daß die beginnende Ausflockung dieser Teilchen auf eine Kristallisation der Polydimethylsiloxan-Ketten zurückzuführen ist, bedingt durch die wirkenden van der Waals-Anziehungskräfte. Diese Hypothese wurde nun durch Röntgenuntersuchungen bei tiefer Temperatur bestätigt.
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References
Barrett, K. E. J., Dispersion Polymerization in Organic Media, Wiley (London, 1975).
Croucher, M. D., M. L. Hair, Macromolecules11, 874 (1978).
Croucher, M. D., M. L. Hair, J. Phys. Chem.83, 1712 (1979).
Napper, D. H., J. Colloid Interface Sci.58, 390 (1977).
Patterson, D., Macromolecules2, 672 (1969).
Everett, D. H., J. F. Stageman, Colloid Polymer Sci.255, 293 (1977).
Everett, D. H., J. F. Stageman, J. Chem. Soc. Faraday Discussions65, 230 (1978).
Kuwahara, N., M. Kaneko, Makromol. Chem.11, 874 (1978).
Sundararajan, P. R., G. K. Hamer, M. D. Croucher, Macromolecules, 1980.
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Croucher, M.D., Hair, M.L. & Sundararajan, P.R. Origin of the lower critical flocculation temperature in polymer colloids stabilized by polydimethylsiloxane. Colloid & Polymer Sci 258, 408–410 (1980). https://doi.org/10.1007/BF01480832
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DOI: https://doi.org/10.1007/BF01480832