Influence of silica matrix morphology on characteristics of grafted nanozirconia

Effects of surface modification and thermal annealing on the interfacial dynamics in core–shell nanocomposites based on silica and adsorbed PDMS

“…Preparation and morphological characterization of initial oxides have been previously described [36], therefore we repeat here briefly the preparation procedure. Fumed silica A-380 (pilot plant of the Institute of Surface Chemistry, Kalush, Ukraine) was used as initial substrate for the development of zirconia nanoparticles at various amounts by reiteration of the respective reaction cycle from 1 to 4 (resulted in $6 and $16 wt% zirconia, respectively [36]).…”

“…Additionally, we showed [27] that zirconia modification on fumed silica of low specific surface area, S BET , ($58 m 2 /g) resulted in slightly increased S BET and in faster, stronger and more cooperative interfacial relaxation. In order to study in more depth the above effects, we manipulate here the surface characteristics of the initial silica of high S BET ($342 m 2 /g) by generating crystalline zirconia nanoparticles (same as in our recent study [27]) on the initial silica particles (smoothened surfaces), before adsorption of the polymer [36]. The investigation involves differential scanning calorimetry (DSC) for thermal transitions and broadband dielectric spectroscopy (BDS) for polymer dynamics.…”

“…Materials under investigation consist of linear polydimethylsiloxane (PDMS) adsorbed in amorphous fumed silica (SiO 2 ) aggregates, in systems of the core-shell type [36]. The adsorption is thought mainly physical (hydrogen bonding) [37].…”

Silica-supported ceria–zirconia and titania–zirconia nanocomposites: Structural characteristics and electrosurface properties

“…There are many publications on preparation, structure, and properties of CeO 2 -TiO 2 [3,[12][13][14], CeO 2 -ZrO 2 [2,[14][15][16], TiO 2 -SiO 2 [17], ZrO 2 -SiO 2 [4,9,11,[18][19][20], and CeO 2 (or TiO 2 ) -ZrO 2 -SiO 2 composites [5,6,[21][22][23]. Numerous synthesis routes have been used to prepare binary and ternary oxides including impregnation, sol-gel, co-precipitation, pyrogenic and other methods [22,24,25].…”

Low-temperature formation of apatite structure of neodymium silicate in silica matrix

“…At the same time, in the presence of some other oxides fumed silica is capable to crystallize to cristobalite form [21][22][23].…”