Magnesium stearate

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Magnesium stearate
Magnesium stearate.png
IUPAC name
Magnesium octadecanoate
557-04-0 YesY
3D model (Jmol) Interactive image
ChemSpider 10704 YesY {CH}
ECHA InfoCard 100.008.320
E number E572 (acidity regulators, ...)
PubChem 11177
UNII 70097M6I30 YesY
Molar mass 591.27 g/mol
Appearance light white powder
Odor slight
Density 1.026 g/cm3
Melting point 88.5 °C (191.3 °F; 361.6 K)
0.003 g/100 mL (15 °C)
0.004 g/100 mL (25 °C)
0.008 g/100 mL (50 °C)
Solubility negligible in ether and alcohol
slightly soluble in benzene
Safety data sheet External MSDS
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oil Health code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentine Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point 250 °C (482 °F; 523 K)
Lethal dose or concentration (LD, LC):
> 1000 mg/kg (oral, rat)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
YesY verify (what is YesYN ?)
Infobox references

Magnesium stearate is the chemical compound with the formula Mg(C
. It is a soap, consisting of salt containing two equivalents of stearate (the anion of stearic acid) and one magnesium cation (Mg2+). Magnesium stearate is a white, water-insoluble powder. Its applications exploit its softness, insolubility in many solvents, and low toxicity. It is used as a release agent and as a component or lubricant in the production of pharmaceuticals and cosmetics.[1]


Magnesium stearate is produced by the reaction of sodium stearate with magnesium salts or by treating magnesium oxide with stearic acid.[1] Some nutritional supplements specify that magnesium stearate be sourced from vegetable-derived stearic acid.(soy)[2]


Magnesium stearate is often used as an anti-adherent[3] in the manufacture of medical tablets, capsules and powders.[4] In this regard, the substance is also useful, because it has lubricating properties, preventing ingredients from sticking to manufacturing equipment during the compression of chemical powders into solid tablets; magnesium stearate is the most commonly used lubricant for tablets.[5] Magnesium stearate can also be used efficiently in dry coating processes.[6][7][8]

Magnesium stearate is also used to bind sugar in hard candies like mints, and is a common ingredient in baby formulas.[citation needed]


Magnesium stearate is a major component of "bathtub rings." When produced by soap and hard water, magnesium stearate and calcium stearate both form a white solid insoluble in water, and are collectively known as "soap scum."[9]


Magnesium Stearate is generally considered safe for human consumption at levels below 2500 mg/kg per day.[10] In 1979, the FDA's Subcommittee on GRAS (generally recognized as safe) Substances (SCOGS) reported, "There is no evidence in the available information on ... magnesium stearate ... that demonstrates, or suggests reasonable grounds to suspect, a hazard to the public when they are used at levels that are now current and in the manner now practiced, or which might reasonably be expected in the future."[11]


  1. ^ a b Angelo Nora, Alfred Szczepanek, Gunther Koenen, "Metallic Soaps" in Ullmann's Encyclopedia of Industrial Chemistry 2005 Wiley-VCH, Weinheim. doi:10.1002/14356007.a16_361
  2. ^ "Quick search results of the DSLD". Dietary Supplement Label Database. National Institutes of Health. Retrieved 27 December 2015. 
  3. ^ Ritter, Steve (2008). "What's That Stuff? Excipients: Inactive ingredients in medicines serve multiple functions in drug delivery". Chemical & Engineering News. 86 (1): 25. doi:10.1021/cen-v086n001.p025. 
  4. ^ Sworbrick, James; Boylan, James C. (1990). Encyclopedia of pharmaceutical technology. p. 2274. ISBN 9780824728243. 
  5. ^ Weiner, Myra L.; Kotkoskie, Lois A. (1999). Excipient Toxicity and Safety. p. 10. ISBN 9780824782108. 
  6. ^ Ouabbas Y, Dodds J., Galet L., Chamayou A. , Baron M., Particle-particle coating in a cyclomix impact mixer, Powder Technol., 189 (2009), 245-252
  7. ^ Thomas G., Ouabbas Y., Grosseau P., Baron M., Chamayou A., Galet L., Modeling the main interaction forces between powder particles. Application to silica gel-magnesium stearate mixtures, Applied Surface Science, 255 (2009), 7500-7507
  8. ^ Sato A., Serris E., Grosseau P., Thomas G., Galet L., Chamayou A. , Baron M., Experiment and simulation of dry particle coating, Chem. Eng. Science, 86 (2013), 164-172
  9. ^ Anne Marie Helmenstine; "Why Is It Harder to Rinse off Soap with Soft Water?"; retrieved 19 Mar 2010
  10. ^ Søndergaarda, D.; Meyera, O.; Würtzena, G. (1980). "Magnesium stearate given peroprally to rats. A short term study". Toxicology. 17 (1): 51–55. doi:10.1016/0300-483X(80)90026-8. PMID 7434368. 
  11. ^ FDA's SCOGS Database; Report No. 60; ID Code: 557-04-0; Year: 1979