Calcium stearate

Calcium stearate
IUPAC name Calcium octadecanoate
Other names E470
Identifiers
CAS number	1592-23-0 Y
PubChem	15324
ChemSpider	14587 Y
UNII	776XM7047L Y
Jmol-3D images	Image 1
SMILES [Ca+2].[O-]C(=O)CCCCCCCCCCCCCCCCC.[O-]C(=O)CCCCCCCCCCCCCCCCC
InChI InChI=1S/2C18H36O2.Ca/c2*1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20;/h2*2-17H2,1H3,(H,19,20);/q;;+2/p-2 Y Key: CJZGTCYPCWQAJB-UHFFFAOYSA-L Y InChI=1/2C18H36O2.Ca/c2*1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18(19)20;/h2*2-17H2,1H3,(H,19,20);/q;;+2/p-2 Key: CJZGTCYPCWQAJB-NUQVWONBAL
Properties
Molecular formula	C36H70CaO4
Molar mass	607.02 g mol−1
Exact mass	606.490002
Appearance	white to yellowish-white powder
Density	1.08 g/cm3
Melting point	155 °C
Solubility in water	0.004 g/100 mL (15 °C)
Solubility	soluble in hot pyridine slightly soluble in oil insoluble in alcohol, ether
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Calcium stearate is carboxylate of calcium that is found in some lubricants and surfactants. It is a white waxy powder.

Production and occurrence

Calcium stearate is produced by heating stearic acid, a fatty acid, and calcium oxide:

2 C₁₇H₃₄COOH + CaO → (C₁₇H₃₄COO)₂Ca + H₂O

It is also the main component of soap scum, a white solid that forms when soap is mixed with hard water. Unlike soaps containing sodium and potassium, calcium stearate is insoluble in water and does not lather well.^{[citation needed]} Commercially it is sold as a 50% dispersion in water or as a spray dried powder. As a food additive it is known by the generic E number E470.

Applications

• Calcium stearate is used as a flow agent in powders including some foods (such as Smarties), a surface conditioner in hard candies such as Sprees, a waterproofing agent for fabrics, a lubricant in pencils and crayons.
• The concrete industry uses calcium stearate for efflorescence control of cementitious products used in the production of concrete masonry units i.e. paver and block, as well as waterproofing.
• In the paper production, calcium stearate is used as a lubricant to provide good gloss, preventing dusting and fold cracking in paper and paperboard making.
• In plastics, it can act as an acid scavenger or neutralizer at concentrations up to 1000ppm, a lubricant and a release agent. It may be used in plastic colorant concentrates to improve pigment wetting. In rigid PVC, it can accelerate fusion, improve flow, and reduce die swell.
• Applications in the personal care and pharmaceutical industry include tablet mold release, anti-tack agent, and gelling agent.
• Calcium stearate is a component in some types of defoamers.