ISSN:
1435-1536
Keywords:
Latex light scattering
;
structure factor
;
turbidimetry
;
depletion forces
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract A turbidimetric analysis of the depletion interaction in mixtures of latexes and non-adsorbing polymers is presented. It is demonstrated that turbidimetry explores the small-angle part of the structure factorS(q) (q=(4π/λ)sin(θ/2),θ is the scattering angle, andλ the wavelength of the radiation in the medium) and allows to extrapolate to S(0) in very good accuracy. Turbidimetry is insensitive towards multiple scattering and the analysis can therefore be extended to high latex concentrations. The measured turbidityτ is fully determined by the scattering intensity of the latex spheres, whereas the dissolved polymer does not contribute appreciably toτ. Therefore,S(0) thus obtained can be used to assess the attractive depletion forces between the latex particles in these mixtures. It is shown that the volume-exclusion potential as modified by Lekkerkerker et al. [17] allows to account quantitatively for the dependence ofS(0) on latex concentration as well as on polymer concentration.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01182411
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