Aqueous Dispersions of Silica Stabilized with Oleic Acid Obtained by Green Chemistry

Nanomaterials

Cristina Lavinia Nistor³  Raluca Ianchis³  Marius Ghiurea³  Cristian-Andi Nicolae³  Catalin-Ilie Spataru³  Daniela Cristina Culita¹  Jeanina Pandele Cusu¹  Victor Fruth¹  Florin Oancea³  Dan Donescu³  Jordi Sort²  Yoshihiro Ito²  Baoshan Xing² 

[1] “Ilie Murgulescu” Institute of Physical Chemistry of Romania Academy, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania;;R & D National Institute for Chemistry and Petrochemistry, Spl. Independentei 202, 6th District, 060021 Bucharest, RomaniaR & D National Institute for Chemistry and Petrochemistry, Spl. Independentei 202, 6th District, 060021 Bucharest, Romania;

关键词: nanosilica;    hydrophobic;    octadecyltrimethoxysilane;    oleic acid;    sodium silicate;   

DOI  :  10.3390/nano6010009

来源: mdpi

【 摘 要 】

The present study describes for the first time the synthesis of silica nanoparticles starting from sodium silicate and oleic acid (OLA). The interactions between OLA and sodium silicate require an optimal OLA/OLANa molar ratio able to generate vesicles that can stabilize silica particles obtained by the sol-gel process of sodium silicate. The optimal molar ratio of OLA/OLANa can be ensured by a proper selection of OLA and respectively of sodium silicate concentration. The titration of sodium silicate with OLA revealed a stabilization phenomenon of silica/OLA vesicles and the dependence between their average size and reagent’s molar ratio. Dynamic light scattering (DLS) and scanning electron microscopy (SEM) measurements emphasized the successful synthesis of silica nanoparticles starting from renewable materials, in mild condition of green chemistry. By grafting octadecyltrimethoxysilane on the initial silica particles, an increased interaction between silica particles and the OLA/OLANa complex was achieved. This interaction between the oleyl and octadecyl chains resulted in the formation of stable gel-like aqueous systems. Subsequently, olive oil and an oleophylic red dye were solubilized in these stable aqueous systems. This great dispersing capacity of oleosoluble compounds opens new perspectives for future green chemistry applications. After the removal of water and of the organic chains by thermal treatment, mesoporous silica was obtained.

【 授权许可】

CC BY   
© 2016 by the authors; licensee MDPI, Basel, Switzerland.