Premium
Development of Short‐Range Repulsive Potentials by Short‐Chain Surfactants in Aqueous Slurries
Author(s) -
Luther Erik P.,
Lange Fred F.,
Pearson Dale S.,
Colic Miroslav
Publication year - 1999
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1999.tb01725.x
Subject(s) - adsorption , aqueous solution , pulmonary surfactant , chemical engineering , particle (ecology) , viscosity , chemistry , cationic polymerization , slurry , particle size , materials science , mineralogy , polymer chemistry , organic chemistry , composite material , oceanography , engineering , geology
The effect of both cationic ( n ‐trimethylammonium bromide, C n TAB) and zwitterionic (phosphocholine, C n C n PC) surfactants on the properties of aqueous slurries of Si 3 N 4 was studied. These surfactants were expected to adsorb to the surface of Si 3 N 4 particles to produce short‐range repulsive interparticle potentials that might be useful for the colloidal processing of advanced ceramic powders. Electrophoretic, adsorption, and viscosity measurements showed that longer‐chain‐length surfactants (C n TAB, n ≥ 12, and C n C n PC, n ≥ 9) strongly adsorb. Surfactants with shorter chain lengths were highly soluble and did not adsorb. Although the C n TAB, n ≥ 12, surfactants produced very weak particle networks with a low viscosity, the packing density during consolidation was very low, and the bodies were brittle (cracked before plastic deformation). The less‐soluble, longer‐chained C n C n PC, n ≥ 9, surfactants did produce high particle‐packing densities but also produced brittle bodies. In all cases, it appeared that the surfactants could be pushed away from the surface during particle packing.