Volatile phenols sample preparation

There are a range of metal catalyst/activators used in phenolic and polyurethane adhesives that can be monitored using ICP-OES. In the metal analysis study of phenolic adhesives, the salts Ca(S03H)2 and Cu(S03H)2 were formulated as listed in Table 6.21, with and without fillers. Several metal salts are employed in polyurethane adhesives for the reasons listed in Table 6.23. As part of the sample preparation study of these products metal salts were formulated into typical polyurethane products consisting of volatile and non-volatile metal salts, listed in Table 6.24, showing the metals of interest and the concentrations expected. 

This sample preparation method involves steam distillation of the volatile organic components of a sample followed by preconcentration by LEE using a water-insoluble solvent. SDE served as unique clean-up and preconcentration step before derivatization, in the GC-MS determination of polycyclic aromatic hydrocarbons, phenols and aromatic amines in particulate phase mainstream cigarette smoke . Preconcentration by the SDE... 

Chemical derivatization reactions in analytical chemistry have been used to enhance detection, improve volatility for GC, or enhance selectivity such as for chiral separations. Sample preparation derivatization reactions occur at an active hydrogen such as an alcohol, phenol, amine, or sulfhydryl. The reaction types are largely alkylations, acylations, silylations, and condensations. A comprehensive review of derivatization reaction is available (53). 

Acidity (as acetic acid) Mix 38 mL of sample with an equal volume of carbon dioxide-free water, add 0.1 mL of phenol-phthalein TS, and titrate with 0.1 A sodium hydroxide. Not more than 0.1 mL is required to produce a pink color. Aldehydes (as formaldehyde) Prepare a Sample Solution by diluting 2.5 mL of sample with 7.5 mL of water. Prepare a Standard Solution containing 40 p,g of formaldehyde in 10 mL of water. Add 0.15 mL of a 5% solution of 5,5-dimethyl-1,3-cyclohexanedione in alcohol to each solution, and evaporate on a steam bath until the Acetone is volatilized. Dilute to 10 mL with water, and cool quickly in an ice bath while stirring vigorously. Any turbidity produced in the Sample Solution does not exceed that produced in the Standard Solution. 

TVA and Differential Distillation Analysis (or SATVA) have been applied to studies on the effect of chlorinated hydrocarbon fire retardants [945, 946]. Rigby [947] has studied vapour evolution from LDPE cable insulation material (20-60 mg) by means of TVA-ToFMS, a form of in-source TD-MS, and identified Santonox R and traces of the cross-linking agent dicumyl peroxide in the low-temperature peak of the TVA curve. The TVA curves of commercial LDPE and of fl eshly prepared LDPE/Santonox suggested that in commercial samples Santonox was distributed closer to the surface than in freshly prepared ones. The detection limit (using ToF-MS) for Santonox bulk-distributed in LDPE was about 0.01%. Chiantore et al. [948] have characterised a phenol-formaldehyde (PF) resin by means of TVA (to isolate the lower-MW components) and SEC (both on volatile fractions and residues). 

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