Abstract
Hydrophilic and hydrophobic colloid SiO2 particles dispersed in benzene-n-heptane mixtures were studied by small-angle X-ray scattering (SAXS) in an He atmosphere. The adsorption of the components, the theological properties and the optical density of the suspensions were also determined. In mixtures of benzene and n-heptane, adhesion between the particles decreased due to the positive adsorption of benzene, since, according to results obtained by micro-calorimetry the heat of wetting increases in benzene-rich mixtures. According to SAXS measurements, the difference between hydrophilic and hydrophobic particles is well characterized by the primary scattering intensities I(o). Correlation length and the course of the distance distribution function P(r), were calculated from I(h), yield information on aggregation and on the stability of the disperse system. The theological flow curves reveal that in n-heptane there are strong adhesive interactions between both hydrophilic and hydrophobic particles. The yield value τ(B) is characteristic of interparticle interactions, and changes in parallel with the tail-end constant K, and with the parameter of inhomogeneity. Aggregation is also demonstrated by the observation of the relative internal surface of the suspension changes with the composition of the mixture.
| Original language | English |
|---|---|
| Pages (from-to) | 233-243 |
| Number of pages | 11 |
| Journal | Colloids and Surfaces A: Physicochemical and Engineering Aspects |
| Volume | 133 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - Feb 28 1998 |
Fingerprint
Keywords
- Adsorption
- Hydrophilic/hydrophobic surfaces
- Rheology of suspensions
- SAXS
- Silica particles
- Wetting
ASJC Scopus subject areas
- Colloid and Surface Chemistry
- Physical and Theoretical Chemistry
Cite this
Small-angle X-ray scattering of colloidal aerosil particles in binary liquid mixtures. / Dékány, I.; Turi, László.
In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, Vol. 133, No. 3, 28.02.1998, p. 233-243.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Small-angle X-ray scattering of colloidal aerosil particles in binary liquid mixtures
AU - Dékány, I.
AU - Turi, László
PY - 1998/2/28
Y1 - 1998/2/28
N2 - Hydrophilic and hydrophobic colloid SiO2 particles dispersed in benzene-n-heptane mixtures were studied by small-angle X-ray scattering (SAXS) in an He atmosphere. The adsorption of the components, the theological properties and the optical density of the suspensions were also determined. In mixtures of benzene and n-heptane, adhesion between the particles decreased due to the positive adsorption of benzene, since, according to results obtained by micro-calorimetry the heat of wetting increases in benzene-rich mixtures. According to SAXS measurements, the difference between hydrophilic and hydrophobic particles is well characterized by the primary scattering intensities I(o). Correlation length and the course of the distance distribution function P(r), were calculated from I(h), yield information on aggregation and on the stability of the disperse system. The theological flow curves reveal that in n-heptane there are strong adhesive interactions between both hydrophilic and hydrophobic particles. The yield value τ(B) is characteristic of interparticle interactions, and changes in parallel with the tail-end constant K, and with the parameter of inhomogeneity. Aggregation is also demonstrated by the observation of the relative internal surface of the suspension changes with the composition of the mixture.
AB - Hydrophilic and hydrophobic colloid SiO2 particles dispersed in benzene-n-heptane mixtures were studied by small-angle X-ray scattering (SAXS) in an He atmosphere. The adsorption of the components, the theological properties and the optical density of the suspensions were also determined. In mixtures of benzene and n-heptane, adhesion between the particles decreased due to the positive adsorption of benzene, since, according to results obtained by micro-calorimetry the heat of wetting increases in benzene-rich mixtures. According to SAXS measurements, the difference between hydrophilic and hydrophobic particles is well characterized by the primary scattering intensities I(o). Correlation length and the course of the distance distribution function P(r), were calculated from I(h), yield information on aggregation and on the stability of the disperse system. The theological flow curves reveal that in n-heptane there are strong adhesive interactions between both hydrophilic and hydrophobic particles. The yield value τ(B) is characteristic of interparticle interactions, and changes in parallel with the tail-end constant K, and with the parameter of inhomogeneity. Aggregation is also demonstrated by the observation of the relative internal surface of the suspension changes with the composition of the mixture.
KW - Adsorption
KW - Hydrophilic/hydrophobic surfaces
KW - Rheology of suspensions
KW - SAXS
KW - Silica particles
KW - Wetting
UR - http://www.scopus.com/inward/record.url?scp=0032574280&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032574280&partnerID=8YFLogxK
U2 - 10.1016/S0927-7757(97)00207-0
DO - 10.1016/S0927-7757(97)00207-0
M3 - Article
AN - SCOPUS:0032574280
VL - 133
SP - 233
EP - 243
JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects
JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects
SN - 0927-7757
IS - 3
ER -