Dispersion of Ceramic Particles in Aqueous Media with Surface‐Grafted Dispersant

Abstract

One important goal to be achieved in the colloidal processing of ceramics is to fully disperse a solid substance into finely divided particles in a liquid medium to avoid the generation of agglomerates. A novel preparation method of aqueous ceramic slurries is described in this paper. The process can be characterized by creating a chemically grafted dispersant molecule layer on particles' surfaces which is very soluble in water. The tuned configuration of dispersant molecules causes neither bridging nor depletion flocculation but induces steric repulsion effectively. The obtained aqueous slurry was quite stable and yielded green bodies with high relative density.

Thermal conductivity enhancement of alumina/polyamide composites via interfacial modification

“…As temperature is raised, polyoxyethylene chains release water molecules and become less hydrophilic [22]. In a poor solvent, where the energy of polymer-solvent interaction is unfavorable, more compact configurations, in which polymer-polymer contacts occur frequently, will be preferred [23][24][25]. Hot water is a poor solvent for polyoxyethylene chains.…”

In Situ Characterization of Spinel Nanoceramic Suspensions

“…The filaments indicated by arrows are bundles of the polymeric dispersant, formed during sublimation before observation, and may imply either a redundant or deficient amount of dispersant in the suspension. An excessive amount of polymer causes “bridging”, or links between the particles, which holds them together, and promotes flocculation . On the other hand, when the amount of dispersant is too low, particle coverage by adsorption of the polymer is incomplete and may also provide a driving force for particles to cluster together .…”

Evaluation of Physical Properties of Zirconia Suspension with Added Silane Coupling Agent for Additive Manufacturing Processes

“…The silane coupling agent was presumed to enable the homogeneous dispersion of zirconia particles in the suspension. As a result, density was evenly distributed during particle growth [36]. The higher the relative density, the higher the sample density; hence, mechanical properties, such as strength, can be enhanced.…”

“…The addition of silane coupling agents to the samples promoted the homogeneous commixture of organic (photocurable polymers) and inorganic (zirconia) substances. As a result, dispersibility improved and hardness increased [21,28,36].…”