Effect of polyethyleneimine-fatty acid complex type dispersant structure on the overall processing chain of Si3N4 ceramics using multicomponent non-aqueous slurries

Rapid three-dimensional structuring of transparent SiO2 glass using interparticle photo-cross-linkable suspensions

“…Preparation of photo-responsive suspension. First, PEI-OA complexes with different OA contents (15-50 mol% of OA in PEI monomer units, calculated assuming all amines were secondary amines) in PEI were prepared in a manner similar to that in our previous report [34][35][36][37] . Briefly, 0.500 g of PEI and 0.493, 0.986, and 1.642 g of OA, corresponding to 15, 30, and 50 mol% OA, respectively, were mixed with α-terpineol to prepare a 10.0 g solution.…”

“…Briefly, SiO 2 fine particles are dispersed in a mixed solvent of α-terpineol and tetrahydrofuran (THF) with assistance from polyethyleneimine partially complexed with oleic acid (PEI-OA). PEI-OA is designed to serve as a universal functional polymer dispersant that could be attached onto various series of particles [34][35][36][37] . The content of OA segment in PEI-OA is varied to tune the dispersion stability of SiO 2 fine particles in the solvent while the remaining un-complexed amino groups in PEI-OA were expected to act as cross-linking reaction sites.…”

Granulation of Silicon Nitride Powders by Spray Drying: A Review

“…Furthermore, this table shows that there are investigations in which other solvents were used. For instance, Iijima et al [ 61 ] have been used toluene as solvent. In this research, the effect of fatty acid structure of PEI-fatty acid complex on the dispersion properties of Si 3 N 4 -Y 2 O 3 -Al 2 O 3 -AlN-TiO 2 /toluene slurries was investigated.…”

“…Therefore, obtaining silicon nitride parts with a relative density of >85% even at high sintering temperatures is rather difficult. To intensify the sintering of Si 3 N 4 powders, oxide additions as sintering aids (Y 2 O 3 , Al 2 O 3 , MgO, CeO 2 , La 2 O 3 , and others) are used in an amount of 5–25% [ 36 , 61 , 62 , 63 , 67 , 69 , 71 , 73 ]. During sintering, these oxides interact with SiO 2 and oxynitrides, which are formed on the surface of silicon nitride particles during their synthesis, and together form a liquid phase that enhances sintering of Si 3 N 4 -based materials [ 76 , 77 ].…”

“…Formation of the potential flaws during compaction depended on the mechanical properties and the resultant compaction behavior of the granules. In [ 61 ], the authors also kept the ratio of the solid phase to the liquid equal to ~65%.…”