EFFECT OF DIMETHYLFORMAMIDE ON THE GELS STRUCTURE OF SiO2 -gels MATERIALS FROM TMOS AND TEOS
Main Authors: | Kancono, Warsito, Salleh, Harun, Shahrul, Ismail, H.B, Senin |
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Format: | BookSection PeerReviewed Book |
Bahasa: | eng |
Terbitan: |
Kolej Universiti Sains dan Teknologi Malaysia
, 2006
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Subjects: | |
Online Access: |
http://repository.unib.ac.id/446/1/B3%20Lengkap.pdf http://repository.unib.ac.id/446/ |
Daftar Isi:
- The effect of dimethylformamide (DMF) on the gelation processes of tetramethoxysilane (TMOS) and tetraethoxysilane (TEOS) were investigated by Polarization Microscope. The hydrolysis and polycondensation reactions are carried out at 50°C, with ammonium fluoride catalysts. The sol-gel was investigated on the SiO2-gels formed using CP MAS29Si NMR spectroscopy, BET and XRD. The results have shown that the hydrolysis rate are as a function of the quantity DMF; the highest concentration of DMF produces the fastest gelation time[3, 4]. Both products showed the same textural properties. N adsorption-desorption isotherms have indicated that at higher quantity DMF an ncrease in particle sizes and greater increase in the mean pore size. Micrographs have shown hat sols are made of primary particles of about 10-20 Å in diameter. These primary structural units organize to form the secondary particles with diameter about 40-70 Å at the agglomeration solid.