Systematic Approach for Dispersion of Silicon Nitride Powder in Organic Media: II, Dispersion of the Powder

Abstract

A novel dispersant-O-(2-aminopropyl)-O-(2-methoxyethyl)-polypropylene glycol (AMPG)-was developed to disperse submicrometer-sized Si 3 N 4 powder in nonaqueous media, based on the surface chemistry of the powder. The dispersing phenomena and mechanisms have been studied systematically, both in model systems (using atomic force microscopy and ellipsometry) and in powder systems (using rheological behavior and adsorption isotherms). The results from the model systems correlated well with those from wet powder systems. It is demonstrated that highly concentrated (with a solids volume fraction of >0.50) and colloidally stable nonaqueous Si 3 N 4 suspensions can be realized using AMPG.

Studies on rheology of ceramic inks and spread of ink droplets for direct ceramic ink jet printing

“…The same pattern is observed for zirconia based ink as shown in Fig. 5 and these graphs are showing a behavior which is in agreement with the graphs reported in literature [19,20,21]. At higher volume content of ceramic, the apparent viscosity values significantly differ for these two inks.…”

The influence of solid loading in suspensions of a submicrometric alumina powder on green and sintered pressure filtrated samples

“…It is well known that well-dispersed suspensions are characterized by slow sedimentation, a cloudy supernatant, and a higher sediment density [14]. In this case the highest density of sediment was reached at dispersant concentration of 2.2 wt.%, which is in good agreement with the results of viscometry measurements (Fig.…”

Preparation of polyamide 6/silica nanocomposites from silica surface initiated ring-opening anionic polymerization

“…This suspension can remain stable for a period of at least 2 weeks, suggesting the formation of covalent linkage between silica and PA6, which did not allow the separation of the two phases. This phenomenon could be attributed to the steric hindrance formed by the grafting of PA6 chains onto nano-sized silica particles, which in turn kept the particles from aggregation and reduce their number of accessible sites [25,26]. FTIR spectroscopic analysis provided additional evidence that the silica surface reaction proceeded as illustrated in Figure 1.…”