Organofunctionalized surfaces

Organofunctionalized Metal-Modified Surfaces for Chromatographic Applications... 

It has been shown that organofunctionalized silica surfaces further modified with in situ synthesized copper complexes can be used to produce new stationary phases for HPLC [4]. The immobilized copper complexes provide new sites in the stationary phase that can interact strongly with basic organic compounds. A test mixture of compounds such as benzene, toluene, naphthalene, anthracene, pyrene, and nitrobenzene shows that the presence of copper ion complexes on the modified surface strongly affects the retention factor (fe) of the stationary phases. 

In a preliminary experiment to study the adsorption of Cu(II) on organofunctionalized silica surfaces (obtained when Si-OH groups on the silica surface bind with alcoxysilanes), the fractional factorial design whose data are presented in Table 4A.1 was carried out (Cestari et al., 1996). 

CESTARI, A. R. BRUNS, R. E. and AIROLDI, C. A fractional factorial design applied to organofunctionalized silicas for adsorption optimization. Colloids Surfaces A Physicochem. Eng. Aspects 117, 1996, pp. 7-13. 

Silanes are the most common commercial adhesion promoter. They are commonly used to enhance adhesion between polymeric and inorganic materials. They usually have the form XjSi—R, where X is typically a chlorine or alkoxy group and R is the organofunctionality. The organofunctional portion bonds with the resin in the adhesive or the organic medium, and the silane portion bonds to the inorganic or substrate surface. 

The adsorption of MN4-MC on the surface of organofunctionalized silica has also shown to be an efficient way to prepare hybrid materials useful in electroanalysis. Fujiwara et al. [70] described the surface modification of porous Si02/ AI2O3 (SiAl) with a thin layer of 3-n-propylpyridiniumsilsesquioxane polymer (SiPy-) (Fig. 19a). 

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