Direct Potentiometric Titration of Polyethylene Glycols and Their Derivatives with Sodium Tetraphenylboron

An infrared spectrophotometric method of estimating polyethylene glycol 4000.

“…In alkyl acetals, the CH, group adjacent to the oxygen atom appears to have a characteristic frequency near 2,825 cm-' (Brugel and Oster, 1956). Levins and Ikeda (1965) found one absorption band of PEG 1,000 to be approximately at this wave number. At a frequency of approximately 2,880 cm-', the infrared absorption of PEG 4000 is directly proportional to its concentration.…”

Extraction with Metal Bis(dicarbollide) Anions

“…The discovery of the synergetic extraction of alkaline earth cations with polyethylene glycols was based on the insolubility of the barium tetraphenylborate in the presence of these compounds [151] and was published in 1976 [5]. Of course, the PEGs display a synergetic effect for other hydrophobic anions than cobalt bis(dicarbollide) too [5], but extractions with cobalt bis(dicarbollide)s were the most studied.…”

Potentiometric Titrations

“…Polyethylene glycol (118) reacts with Ba*2 to form complex oxonium ions which are precipitated by tetraphenylboron. The excess of the anion is then determined by titration with silver ions using a silver electrode.…”