X-ray photoelectron spectroscopy (XPS) has been used to study the carbon, oxygen and sulphur content of several coking coals, a series of sink-float fractions from a highvolatile coking coal, and several inorganic minerals that are commonly found in coals. Single carbon and oxygen peaks were obtaine
An X-ray photoelectron spectroscopic investigation of the selectivity of hydroxyl derivatization reactions
β Scribed by Ashutosh Chilkoti; Buddy D. Ratner
- Publisher
- John Wiley and Sons
- Year
- 1991
- Tongue
- English
- Weight
- 719 KB
- Volume
- 17
- Category
- Article
- ISSN
- 0142-2421
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β¦ Synopsis
Abstract
The Selectivity of trifluoroacetic anhydride (TFAA), used for the vaporβphase derivatization of hydroxyl groups in multifunctional oxygenβcontaining polymeric surfaces, has been investigated by XPS studies on model epoxides systems. The reactivity of TFAA towards epoxides observed here is discussed in the context of the large amount of published literature implying high selectivity of this reaction towards hydroxyl groups. Acetyl chloride (AcCl) and heptafluorobutyryl chloride (HFBuCl), used to derivatize hydroxyl groups in the literature, were also examined, with regard to crossβreaction with epoxides. Both AcCl and HFBuCl react with epoxides, forming chloroacetates and perfluorinated chloroacetates, respectively. Moreover, HFBuCl is shown to react with double bonds forming perfluorinated chloroacetates, while AcCl is unreactive towards them. The reactivity of HFBuCl to wards epoxides and unsaturation compromises its use as a derivatization reagent of hydroxyl groups. However, the unique reaction products formed by exposure of hydroxyls and epoxides to AcCl vapor may allow hydroxyl species to be distinguished from epoxides in multifunctional carbonβoxygen polymeric surfaces.
π SIMILAR VOLUMES
## Abstract Polyester powder coatings are used for corrosion protection of different materials. XPS studies were performed in order to characterize such coatings on steel surfaces as a preβtreatment for following applications like gluing. Different surface treatments by alkaline cleaner, plasma tre