Magnesium Stearate (MS)

Luyao Approval No. F2014068

CAS NO.:557-04-0

Packaging Specifications:10 kg/bag

Quality Standard:CP2015 USP Current Edition

Main Uses:This product has lubricating, anti-sticking, and flow-aiding properties. In pharmaceutical preparations, it is mainly used as a lubricant, glidant, or anti-adhesive agent in tablets and capsules.

Magnesium stearate, with the chemical formula C36H70MgO4 and a molecular weight of 591.24, is an organic compound. It is a fine, white, non-gritty powder with a slippery feel when in contact with the skin. It is insoluble in water, ethanol, or ether. Magnesium stearate is mainly used as a lubricant, anti-adhesive agent, and glidant. It is particularly suitable for granulating oily and extract-based drugs, producing granules with excellent flowability and compressibility. It is used as a glidant in direct compression tablets. Magnesium stearate can also be used as a filter aid, clarifying agent, and foaming agent, as well as a suspending agent and thickening agent in liquid preparations.

Magnesium Stearate Synthesis Methods

1. Preparation of Sodium Stearate: Dissolve 4.25 parts of sodium hydroxide in 50 parts of water and heat to 85℃ for later use. Add 25 parts of stearic acid to the reaction vessel, add 500 parts of water, and dissolve with stirring. Adjust the temperature to 85-90℃. Slowly add the prepared sodium hydroxide solution to the stearic acid aqueous solution with stirring, maintaining the temperature at 75-80℃. React with stirring until the endpoint. Keep the product sodium stearate solution warm for later use.

Preparation of Magnesium Stearate: Dissolve 15 parts of magnesium sulfate in 150 parts of water, heat to 55℃, and slowly add it to the prepared sodium stearate solution. Carry out a metathesis reaction with stirring. The magnesium stearate produced precipitates as a solid. After the reaction is complete, allow to stand and separate the clear liquid, then wash with water, centrifuge to dehydrate, and dry at 80-85℃ to obtain the finished product.

2. Neutralize 46.6g of stearic acid with 164mL of 1mol/L sodium hydroxide solution to obtain 50g of sodium stearate in 2L of water. Heat the obtained sodium stearate solution to 80℃ and add dropwise a solution prepared by dissolving 20g of magnesium chloride in 100mL of water, stirring continuously. A white precipitate quickly precipitates out. After cooling, filter, wash with water until no chloride ions are present, and finally wash with ethanol. Place 10g of the product in a vacuum desiccator containing concentrated sulfuric acid for 4 weeks to obtain the product Mg(C18H35O2)2·2H2O. Dissolve the remaining product in benzene and reflux for 20min. Pour out the upper yellow liquid layer while hot and evaporate to dryness. The solid obtained can be recrystallized with benzene to obtain the product Mg(C18H35O2)2.