Glycols analytical procedure

Analytical procedures used in connection with glycols are described in the book by Curme and Johnston, pp 328-351 (54 refs are ioduded) and under individual glycols in this Encycl... 

To a 1-liter, three-necked, round-botton flask equipped with a mechanical stirrer, reflux condenser, thermometer, and addition funnel is added 57 gm (0.75 mole) of propylene glycol and 7.5 gm (0.19 mole) of sodium hydroxide. The flask is purged with nitrogen to remove air and heated to 120°C with stirring to dissolve the sodium hydroxide. Then propylene oxide is added (40-45 mole). The reaction mixture is cooled under nitrogen, neutralized with dilute sulfuric acid, filtered, and dried under redueed pressure to give a water-insoluble product with MW 1620 as determined by hydroxyl number or acetylation analytical procedures. 

The analytical procedure [23] is as follows. The propan-2-ol must contain not more than 0.05% water. The phenyl isothiocyanate must have a base content equivalent to not more than 0.006 ml of 0.2 M hydrochloric acid per millilitre. The hydrochloric acid is in propan-2-ol. The solvent referred to is 150 ml ethanediol (ethylene glycol) containing not more than 0.1% water, 250 ml n-heptane and 400 ml propan-2-ol. 

Similarly, as with alcohols, the binodal curves are much better documented than data about equilibrium compositions. It should be taken into acconnt that, in systems with polyethylene glycols, in an addition to not always adeqnate analytical procedures, the appUed PEG or other polymer is not sufficiently characterized. Polymers... 

Fused silica capillary columns of various internal bores and of lengths in the range 25 to 50 m are mainly employed for analytical separations. A variety of polar and non-polar column types are available including those open tubular types with simple wall coatings (WCOT), those with coatings dispersed on porous solid-supports to increase adsorbent surface area (SCOT) and porous layer open tubular (PLOT) columns. Important stationary phases include polyethylene glycol, dimethylpolysiloxane and different siloxane copolymers. Various sample introduction procedures are employed including ... 

Improved Procedures for the Analysis of Gamma-hydroxybutyrate and Ethylene Glycol in Whole Blood Journal of Analytical Toxicology 25 (5) (2001) 328-332. 

Beauchamp CO, Gonias SL, Menapace DP, Pizzo SV. A new procedure for the synthesis of polyethylene glycol-protein adducts—effects on function, receptor recognition, and clearance of superoxide-dismutase, lactoferrin, and alpha-2-macroglobulin. Analyt. Biochem. 1983 131 25-33. 

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