C20H32O2304(average)

Benzoic acid,C12-15alkyl ester [68411-27-8].

Packaging and storage— Preserve in tight,light-resistant containers.

Identification— Its IRabsorption spectrum,obtained by spreading a capillary film of it between sodium chloride plates,exhibits maxima at 2800cm-1(broad);2950cm-1(broad);at 1730cm-1(medium,sharp);at 1270cm-1(medium,sharp);and at 710cm-1(medium,sharp).

Specific gravity á841ñ: between 0.915and 0.935.

Acid value á401ñ: not more than 0.5.

Saponification value á401ñ— Transfer about 2g of Alkyl (C12-15)Benzoate,accurately weighed,to a 200-mLflask.Proceed as directed for Saponification Value underFats and Fixed Oils á401ñ,except to use 50.0mLof 0.5Nalcoholic potassium hydroxide VSinstead of 25.0mL,maintaining reflux for 2hours instead of 30minutes,and rinsing the reflux condenser with 25mLof water after the reflux period:the saponification value is between 169and 182.

Refractive index á831ñ: between 1.483and 1.487,determined at 20.

Viscosity á911ñ— Transfer about 500mLto a tall-form,600-mLbeaker,and adjust the temperature to 25±0.1.Using a suitable rotational viscosimeter with a spindle having a cylinder 5.63cm in diameter and 2.25cm high attached to a shaft 0.32cm in diameter,the distance from the top of the cylinder to the lower tip of the shaft being 2.91cm,and the immersion depth being 6.11cm (No.1spindle),operate the viscosimeter at 100rpm for 60seconds,accurately timed,and record the scale reading.Convert the scale reading to centipoises by multiplying by the constant for the spindle and speed employed.The average of three viscosities obtained is no more than 100centipoises.

Water,Method Iá921ñ: not more than 0.3%.

Residue on ignition á281ñ: not more than 0.5%.

Expert Committee:(EMC)Excipients:Monograph Content

USP28–NF23Page 2953

Phone Number:1-301-816-8262