Organic base-catalyzed sol–gel route to prepare PMMA–silica hybrid materials

2007 ◽  
Vol 56 (3) ◽  
pp. 343-349 ◽  
Author(s):  
Jui-Ming Yeh ◽  
Chi-Fa Hsieh ◽  
Chia-Wen Yeh ◽  
Mei-Jyun Wu ◽  
Hsing-Chung Yang
2019 ◽  
Vol 38 (9) ◽  
pp. 586-597 ◽  
Author(s):  
Ananda S. Amarasekara ◽  
Deping Wang

Two chitosan silica hybrid materials were prepared by a two-step process in 78–84% yields using the homogeneous phase reaction of 3-(triethoxysilyl)propyl isocyanate with chitosan dissolved in 1-n-butyl-3-methylimidazolium chloride ionic liquid (∼10% w/w), which was followed by NH4OH catalyzed hydrolysis of triethoxysilyl groups and then sol-gel process. These new hybrid materials were shown to adsorb up to about 95% of Fe3+ from 5 × 10−4 M aqueous solution at room temperature in 24 h.


2005 ◽  
Vol 11 (8-9) ◽  
pp. 631-641 ◽  
Author(s):  
Wei-Hsiang Weng ◽  
Chih-Chung Chang ◽  
Hui Chen

2020 ◽  
Author(s):  
S. Devaraju ◽  
K. Krishnadevi ◽  
E. Naveena ◽  
M. Alagar

2008 ◽  
Vol 8 (6) ◽  
pp. 3040-3049 ◽  
Author(s):  
Kung-Chin Chang ◽  
Hui-Fen Lin ◽  
Chang-Yu Lin ◽  
Tai-Hung Kuo ◽  
Hsin-Hua Huang ◽  
...  

In this paper, a series of organic–inorganic hybrid materials consisting of epoxy resin frameworks and dispersed nanoparticles of amino-modified silica (AMS) were successfully prepared. First of all, the AMS nanoparticles were synthesized by carrying out the conventional acid-catalyzed sol–gel reactions of tetraethyl orthosilicate (TEOS) in the presence of (3-aminopropyl)-trimethoxysilane (APTES) molecules. The as-prepared AMS nanoparticles were then characterized by FTIR, 13C-NMR and 29Si-NMR spectroscopy. Subsequently, a series of hybrid materials were prepared by performing in-situ thermal ring-opening polymerization reactions of epoxy resin in the presence of as-prepared AMS nanoparticles and raw silica (RS) particles. The as-prepared epoxy-silica hybrid materials with AMS nanoparticles were found to show better dispersion capability than that of RS particles existed in hybrid materials based on the morphological observation of transmission electron microscopy (TEM). The hybrid materials containing AMS nanoparticles in the form of coating on cold-rolled steel (CRS) were found to be much superior in corrosion protection over those of hybrid materials with RS particles when tested by a series of electrochemical measurements of potentiodynamic and impedance spectroscopy in 5 wt% aqueous NaCl electrolyte. The increase of corrosion protection effect of hybrid coatings may have probably resulted from the enhancement of the adhesion strength of the hybrid coatings on CRS coupons, which may be attributed to the formation of Fe—O—Si covalent bond at the interface of coating/CRS system based on the FTIR-RAS (reflection absorption spectroscopy) studies. The better dispersion capability of AMS nanoparticles in hybrid materials were found to lead more effectively enhanced molecular barrier property, mechanical strength, surface hydrophobicity and optical clarity as compared to that of RS particles, in the form of coating and membrane, based on the measurements of molecular permeability analysis, dynamic mechanical analysis, contact angle measurements and ultraviolet-visible transmission spectra, respectively.


Sign in / Sign up

Export Citation Format

Share Document