Coagulation of latex dispersions by inorganic salts: structural effects
2007; Linguagem: Inglês
10.1007/bfb0114475
Autores Tópico(s)Diatoms and Algae Research
ResumoThree types of latices were prepared by polymerization of styrene. In type 1 (without emulsifier) and type 2 series (with sodium dodecyl sulfate) the polymerization was initiated by different amounts of peroxodisulfate. Type 3 latices are co-polymers of styrene and styrene sulfonate prepared without initiator. The dispersions reveal significant differences when coagulated with salts. The differences are related to different surface structures. Type 1 latices are considered "classical" latices with smooth surface which are stabilized by electrostatic repulsion. Latex particles of type 3 are assumed to be surrounded by an envelope or a corona of hairs. The hairs add a considerable amount of steric stabilization to the electrostatic stabilization. In both series the coagulation power increases from Li+ to Cs+ which is explained by changes of the water structure. For the same reason, the coagulation concentrations are also sensitive to the kind of co-ions (anions).
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