Abstract
Small-angle x-ray scattering experiments were performed on concentrated dispersions in benzene, of silica particles coated with octadecyl-chains. Such dispersions are known to exhibit short-ranged attractive particle-interactions which depend on the temperature. At sufficiently low temperature, the attraction gives rise to a reversible phase-separation. In the present study, use was made of this phenomenon to fractionate the system. By analyzing two different fractions, the role of polydispersity in the attractive behavior was investigated.
For both original and fractionated material, scattering curves were measured using a Kratky-camera equipped with a stepscanning setup and monitor-detector. The concentrations investigated were 0.033, 0.363, 0.496, and 0.628 g/ml, at temperatures ranging from 25° to 52°C.
From the intensity-patterns of the dilute dispersions, the average radius of the silica-core was found to be 7 nm for both fractions. The scattering curves of the concentrated dispersions were compared with Baxter's adhesive-hard-sphere model, taking the particle size polydispersity into account. For both fractions, a semi-quantitative model description was obtained. At all temperatures, the fitparameters found show a different particle-strickiness for the two fractions, indicating the existence of a distribution for this property. The temperature dependence of the attraction turned out to be much weaker than in previous studies with larger particles.
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Caljé AA, Agterof WGM, Vrij A (1977) In: Mittal KL (ed) Micellization, solubilization, and microemulsions, vol 2. Plenum Press, New York, p 779
Hilfiker R, Eicke H-F, Geiger S, Furler G, (1985) J Coll Interface Sci 105:378
Robertus C, Philipse WH, Joosten JGH, Levine YK (1989) J Chem Phys 90:4482
Corti M, Minero C, Degiorgio V (1984) J Phys Chem 88:309
de Hek H, Vrij A (1981) J Coll Interface Sci 84:409
Vincent B, Edwards J, Emmett S, Croot R (1988) Colloids & Surfaces 31:267
Bacri J-C, Perzynski R, Salin D, Cabuil V, Massart R (1989) J Coll Interface Sci 132:43
Jansen JW, de Kruif CG, Vrij A (1986) J Coll Interface Sci 114:481
Rouw PW, de Kruif CG (1988) J Chem Phys 88:7799
Jansen JW, de Kruif CG, Vrij A (1986) J Coll Interface Sci 114:501
de Kruif CG, Rouw PW, Briels WJ, Duits MHG, Vrij A, May RP (1989) Langmuir 5:422
Duits MHG, May RP, Vrij A, de Kruif CG (1991) Langmuir 7:62
Penders MHGM, Vrij A, van der Haegen R (1991) J Coll Interface Sci 144:86.
Rouw PW, Woutersen ATJM, Ackerson BJ, de Kruif CG (1989) Physica A 156:876
Duits MHG (1990) unpublished results
Jansen JW, de Kruif CG, Vrij A (1986) J Coll Interface Sci 114:471
Flory PJ, Krigbaum WR (1950) J Chem Phys 18:1086
Vrij A, Penders MHGM, Rouw PW, de Kruif CG, Dhont JKG, Smits C, Lekkerkerker HNW (1991) Faraday Discuss Chem Soc 90:31
Regnaut C, Ravey JC (1989) J Chem Phys 91:1211
Baxter RJ (1968) J Chem Phys 49:2770
Guinier A, Fournet G (1955) Small-angle scattering of x-rays, p 65. Wiley: New York, Chapman and Hall: London
Duits MHG, May RP, de Kruif CG (1990) J Appl Cryst 23:366
Duits MHG, May RP, Vrij A, de Kruif CG (1991) J Chem Phys, 94:4521
Guinier A, Fournet G (1955) Small-angle scattering of x-rays, p 24. Wiley: New York, Chapman and Hall: London
Percus JK, Yevick GJ (1958), Phys Rev 110:1
Ornstein LS, Zernike F (1914) Proc Acad Sci (Amsterdam) 17:793
Seaton NA, Glandt ED (1987) J Chem Phys 86:4668
Seaton NA, Glandt ED (1987) J Chem Phys 87:1785
Kranendonk WGT, Frenkel D (1988) Mol Phys 64:403
Van Helden AK, Jansen JW, Vrij A (1981) J Coll Interface Sci 81:354
Kratky O (1982) In: Glatter O, Kratky O (eds) Small angle x-ray scattering, p 62. Academic Press: London
Pilz I, Glatter O, Kratky O (1979) Methods in Enzymology 61:148
Moonen JAHM (1987) thesis, University of Utrecht
Leopold H (1982) In: Glatter O, Kratky O (eds) Small angle x-ray scattering, p 111. Academic Press: London
Vonk CG (1975) J Appl Cryst 8:340
Porod G (1951) Kolloid Z 124:83
Beniaminy I, Deutsch M (1980) Comp Phys Commun 21:271
Vonk CG (1971) J Appl Cryst 4:340
Porod G (1982) In: Glatter O, Kratky O (eds) Small angle x-ray scattering, p 22. Academic Press: London
Moonen J, Vrij A (1988) Colloid Polym Sci 266:1140
Rouw PW, de Kruif CG (1988) Progr Colloid Polym Sci 76:1
Woutersen ATJM (1990) private communication
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Duits, M.H.G., de Kruif, C.G. & Vrij, A. Particle stickiness variations in colloidal dispersions investigated with small-angle x-ray scattering. Colloid Polym Sci 270, 154–164 (1992). https://doi.org/10.1007/BF00652182
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DOI: https://doi.org/10.1007/BF00652182