Octoxinol 10

(Ph Eur monograph 1553)

C₁₄H₂₁-[C₂H₄O]_n-OH

Ph Eur

DEFINITION

a-[4-(1,1,3,3-Tetramethylbutyl)phenyl]-w-hydroxydeca(oxyethylene).

Mixture consisting mainly of mono-octylphenyl ethers of macrogols corresponding to the formula C₈H₁₇C₆H₄-[OCH₂-CH₂]_n-OH where the average value of n is 10. It may contain free macrogols.

CHARACTERS

Appearance

Clear , colourless or light yellow, viscous liquid.

Solubility

Miscible with water, with ethanol and with vegetable oils.

IDENTIFICATION

A.    Infrared absorption spectrophotometry (2.2.24).

Comparison: Ph. Eur. reference spectrum of octoxinol 10.

Preparation. Film between sodium chloride R plates.

B.    It complies with the test for cloud point (see Tests).

TESTS

Acidity or alkalinity

Boil 1.0 g with 20 ml of carbon dioxide-free water  R for 1 min, with constant stirring. Cool and filter. To 10 ml of the filtrate, add 0.05 ml of bromothymol blue solution R1. Not more than 0.5 ml of 0.01 M hydrochloric acid or 0.01 M sodium hydroxide is required to change the colour of the indicator.

Hydroxyl value (2.5.3, Method A)

85 to 101.

Cloud point

63 C to 70 C.

Dissolve 1.0 g in 99 g of water  R. Transfer about 30 ml of this solution to a test-tube, heat on a water-bath and stir continuously until the solution becomes cloudy. Remove the test-tube from the water-bath (ensuring that the temperature does not increase more than 2 C), and continue to stir. The cloud point is the temperature at which the solution becomes sufficiently clear  that the entire thermometer bulb is plainly seen.

Ethylene oxide and dioxan (2.4.25)

Maximum 1 ppm of ethylene oxide and maximum 10 ppm of dioxan.

Heavy metals (2.4.8)

Maximum 10 ppm.

Dissolve 2.0 g in distilled water  R and dilute to 20.0 ml with the same solvent. 12 ml of this solution complies with limit test A. Prepare the standard using lead standard solution (1 ppm Pb) R.

Water (2.5.12)

Maximum 0.5 per cent, determined on 2.00 g.

Total ash (2.4.16)

Maximum 0.4 per cent, determined on 1.0 g.

STORAGE

In an airtight container .

Ph Eur

Action and use

Pharmaceutical aid.