preparation and characterixation of perflourosilane treated nanosilica and investigation of effect of pH in treatment process

Authors
Saeid Bastani 1
Shaqayeq Soroushnia 2
Mohsen Mohseni Bozorgi 3
Mehran Rostami 4
1 Surface coating and corrosion group, institute for color science and technology, Tehran/ Center of excellence for color science and technology, Tehran
2 Surface treatment, nanosilica, flourosilane, hydrophobic, polar parameter.
3 Polymer and Color engineering department, Amirkabir University, Iran.
4 Nano technology and nano materials group, Institute for color science and technology, Tehran
/amnc.2012.1.4.3
Abstract
In this work nanosilica (aerosol 200) was treated by a perflouroalkoxy-silane at different pH conditions. The treated particles were analyzed with turbidimetry, densitometry, FTIR, TGA and CHN methods. The results show that, the pH values of reactions, were effectiveness and begets different properties in particles, as samples treated in alkaline conditions, had higher flourosilane groups. These hydrophobic and nonpolar groups caused low dispersion stability in solvents with high polar parameter. It was found that the pH of treating bath affected the grafting of silane on the nanosilica surface leading to various structures on treated silica particles.
Keywords
surface treatment
nanosilica
Flourosilane
Hydrophobic
Polar parameter