ISSN:
1435-1536
Keywords:
Diblock copolymers
;
polystyrene-b-poly(vinylpyridine-1-oxide)
;
ternary solvent microemulsions
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 Pseudo-ternary phase diagrams have been constructed for the three-component solvent system (toluene+water+propan-2-ol) containing diblock copolymers of poly(styrene-b-2-vinylpyridine-1-oxide). Microemulsions have been shown to form on the water-rich side of the phase diagram, in the region of the phase boundary without polymer. Dynamic light-scattering experiments have led to droplet size values in the region of 100 nm, with the size depending strongly on the propan-2-ol/water concentration, as well as the amount of solubilised toluene in the core. Viscometry experiments have been carried out to measure polymer aggregation numbers in the microemulsion droplets, and interfacial tension measurements have shown that in the absence of propan-2-ol (effectively a cosurfactant) the limiting value of the oil/water interfacial tension, even an saturation adsorption of the copolymer is ∼ 20 mNm−1. However, addition of propan-2-ol reduces the interfacial tension to the very low values generall commensurate with microemulsion formation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00658287
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