Ultraviolet absorbance, thin layer chromatography

The ultraviolet reflectance absorbance spectrum of a benzoic acid spot on a thin-layer chromatography place was recorded on a Shimadzu CS-930 TLC scanner, and is shown in Figure 5. The spectrum was obtained on a silica-gel F254 pre-coated TLC-plate (E. Merck) after elution with 7 2 2 acetone/ammonia 25 %/isopropanol. The absorbance maximum for this system was determined to be 225 nm. [Pg.15]

Table 5.6 Thin-layer chromatography of ultraviolet absorbers in polyethylene ...

Thin-layer chromatography can provide further information critical in compound identification. Colors from selective chemical detection reactions, behavior in long- and short-wave ultraviolet light, absorbance and/or fluorescence spectra obtained directly on the chromatogram by use of a spectrodensitometer or in solution after elution, and Rp values of derivatives prepared by reaction before, during, or after development (Dallas, 1970 Hais, 1970) can be combined with the Rp values of the sample to increase the degree of probability of correct identification. The maximum amount of information is obtained by applying, if possi-... [Pg.178]

Methods 17 and 18, respectively, determine Cyasorb UV 531 (2-hydroxy-4-n-octoxybenzophenone) in polyolefins by direct infrared spectroscopy and thin-layer chromatography. Phenolic and organophosphorus type antioxidants do not interfere in these procedures. Method 19 describes an ultraviolet spectroscopic method for the determination of Tinuvin 326 ultraviolet absorber in polypropylene. [Pg.10]

METHOD 11 - DETERMINATION OF PHENOLIC AND AMINE ANTIOXIDANTS, ULTRAVIOLET ABSORBERS AND ORGANOTIN STABILIZERS IN POLYALKENES AND OTHER POLYMERS. THIN LAYER CHROMATOGRAPHY. ... [Pg.188]

METHOD 18 - DETERMINATION OF CYASORB UV 531 ULTRAVIOLET ABSORBER IN POLYOLEFINS. THIN LAYER CHROMATOGRAPHY. [Pg.203]

Determination of Cyasorb UV531 ultraviolet absorber in polyalkenes. Thin layer chromatography... [Pg.509]

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