scholarly journals Cross-Condensation Kinetics of Organically Modified Silica Sols

1996 ◽  
Vol 435 ◽  
Author(s):  
S. Prabakar ◽  
R. A. Assink
Keyword(s):  
Modified Silica ◽  
Organically Modified ◽  
Organically Modified Silica ◽  
Silica Sols ◽  
Kinetics Of

scholarly journals Gelation of Poly(Vinylidene Fluoride) Solutions in Native and Organically Modified Silica Nanopores

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 3025 ◽  
Author(s):  
Alejandra Espinosa-Dzib ◽  
Sergey Vyazovkin
Keyword(s):  
Vinylidene Fluoride ◽  
Tetraethylene Glycol ◽  
Modified Silica ◽  
Scanning Calorimetry ◽  
Chain Mobility ◽  
Organically Modified ◽  
Poly Vinylidene Fluoride ◽  
Organically Modified Silica ◽  
Kinetics Of ◽  
Kinetics Of Gelation

The purpose of this study is to highlight the surface and size effects of the nanopores on the thermodynamics and kinetics of gelation. The effects have been probed by applying differential scanning calorimetry to poly(vinylidene fluoride) solutions in tetraethylene glycol dimethyl ether (tetraglyme) and γ-butyrolactone. Nanoconfinement has been accomplished by introducing gels into native and organically modified silica nanopores (4–30 nm). Nanoconfinement has produced two major effects. First, the heat of gelation has decreased three to four times compared to that for the bulk systems. Second, the temperature of gelation has increased by ~40 °C (tetraglyme based systems) and ~70 °C (γ-butyrolactone based systems), the increase being stronger in native nanopores. The effects are discussed in terms of acceleration of gelation due to heterogeneous nucleation at the confining surface, and retardation of gelation due to constricted polymer chain mobility in the middle of the pore volume. Calorimetric data have been subjected to isoconversional kinetics analysis. The obtained temperature dependencies of the activation energies of gelation have been interpreted in the frameworks of the nucleation model of Turnbull and Fisher. The results suggest that nanoconfinement leads to a lowering of both the free energy of nucleation and activation energy of diffusion.

scholarly journals Favourable influence of hydrophobic surfaces on protein structure in porous organically-modified silica glasses

Biomaterials ◽  
2008 ◽  
Vol 29 (18) ◽  
pp. 2710-2718 ◽  
Author(s):  
Bouzid Menaa ◽  
Mar Herrero ◽  
Vicente Rives ◽  
Mayya Lavrenko ◽  
Daryl K. Eggers
Keyword(s):  
Protein Structure ◽  
Modified Silica ◽  
Hydrophobic Surfaces ◽  
Silica Glasses ◽  
Organically Modified ◽  
Organically Modified Silica

Absorption of short-chain to long-chain perfluoroalkyl substances using swellable organically modified silica

2019 ◽  
Vol 5 (11) ◽  
pp. 1854-1866 ◽  
Author(s):  
Eva K. Stebel ◽  
Kyndal A. Pike ◽  
Huan Nguyen ◽  
Heather A. Hartmann ◽  
Mattaeus J. Klonowski ◽  
...  
Keyword(s):  
Short Chain ◽  
Perfluoroalkyl Substances ◽  
Modified Silica ◽  
Wide Range ◽  
Organically Modified ◽  
Organically Modified Silica ◽  
Long Chain

Adsorbents comprising swellable organically modified silica were characterized to optimize the adsorption of a wide range of perfluoroalkyl substances from water.

scholarly journals Template-Free Synthesis of Organically Modified Silica Mesoporous Thin Films for TNT Sensing

2010 ◽  
Vol 2 (10) ◽  
pp. 2892-2897 ◽  
Author(s):  
Adem Yildirim ◽  
Hulya Budunoglu ◽  
Hakan Deniz ◽  
Mustafa O. Guler ◽  
Mehmet Bayindir
Keyword(s):  
Thin Films ◽  
Modified Silica ◽  
Mesoporous Thin Films ◽  
Organically Modified ◽  
Organically Modified Silica ◽  
Template Free

A photorefractive organically modified silica glass with high optical gain

Nature ◽  
2000 ◽  
Vol 408 (6808) ◽  
pp. 64-67 ◽  
Author(s):  
Pavel Cheben ◽  
Francisco del Monte ◽  
Dennis J. Worsfold ◽  
Dave J. Carlsson ◽  
Chander P. Grover ◽  
...  
Keyword(s):  
Silica Glass ◽  
Optical Gain ◽  
Modified Silica ◽  
Organically Modified ◽  
Organically Modified Silica
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