Zinc Stearate

Synonyms: Dibasic zinc stearate; stearic acid zinc salt; octadecanoic acid zinc salt, zinc distearate,

CAS Number: 557-05-1,

Molecular Weight: 632.2,

Chemical Formula: Zn(C18H35O2)2,

EINECS EC Number: 209-151-9,

FEMA: ...

Zinc stearate is a "zinc soap" that is widely used industrially. In this context, soap is used in its formal sense, a metal "salt" of a fatty acid. It is a white solid that repels water. It is insoluble in polar solvents such as alcohol and ether but soluble in aromatic hydrocarbons (e.g., benzene) and chlorinated hydrocarbons when heated. It is the most powerful mold release agent among all metal soaps.

We offer BP Ph Eur USP NF Grade of Zinc Stearate.

Specifications of Zinc Stearate USP grade

Octadecanoic acid, zinc salt;
Zinc stearate CAS 557-05-1.

Zinc Stearate is a compound of zinc with a mixture of solid organic acids obtained from fats and consists chiefly of variable proportions of zinc stearate and zinc palmitate. It contains the equivalent of NLT 12.5% and NMT 14.0% of ZnO.

A. Identification Tests General, Zinc:
Sample solution: Mix 25 g with 200 mL of hot water, add 60 mL of 2 N sulfuric acid, and boil until the fatty acids separate as a transparent layer. Cool the mixture, and remove the solidified layer of fatty acids.
Acceptance criteria: A portion of the water layer meets the requirements.
B. Congealing Temperature:
Analysis: Place the separated fatty acids obtained in Identification test A in a filter wetted with water, and wash with boiling water until free from sulfate. Collect the fatty acids in a small beaker, allow to cool, pour off the separated water, then melt the acids. Filter into a dry beaker while hot, and dry at 105° for 20 min.
Acceptance criteria: The fatty acids congeal at a temperature not below 54C.

Sample solution: Boil 1 g of Zinc Stearate with 50 mL of 0.1 N sulfuric acid for at least 10 min, or until the fatty acids layer is clear, adding more water as necessary to maintain the original volume. Cool, and filter. Wash the filter and the flask thoroughly with water until the last washing is not acid to litmus paper.
Analysis: Add to the combined filtrate and washings 15 mL of ammonia–ammonium chloride buffer and 0.2 mL of eriochrome black. Heat the solution to about 40C and titrate with 0.05 M edetate disodium until the solution is deep blue in color. Each mL of 0.05 M edetate disodium is equivalent to 4.069 mg of ZnO.
Acceptance criteria: 12.5%–14.0% of ZnO

Arsenic: --- NMT 1.5 ppm
Lead: --- NMT 10 ppm.
Alkalies and Alkaline Earths:
Sample solution: Mix 2.0 g with 50 mL of water and add 10 mL of hydrochloric acid. Boil until the solution is clear, filter while hot, and wash the separated fatty acids with about 50 mL of hot water. Render the combined filtrate and washings alkaline with 6 N ammonium hydroxide. Add ammonium sulfide to precipitate the zinc completely, dilute with water to 200 mL, mix, and filter.
Analysis: To 100 mL of the clear filtrate add 0.5 mL of sulfuric acid, evaporate to dryness, and ignite to constant weight.
Acceptance criteria: The weight of the residue does not exceed 10 mg (1.0%).
Packaging and Storage: Preserve in well-closed containers.

Specifications of Zinc Stearate BP Ph Eur Grade

CAS 557-05-1
Action and use: Excipient.

Zinc stearate [(C17H35COO)2Zn; Mr 632] may contain varying proportions of zinc palmitate [(C15H31COO)2Zn; Mr 576.2] and zinc oleate [(C17H33COO)2Zn; Mr 628].
Content: 10.0 per cent to 12.0 per cent of Zn.

Appearance: Light, white or almost white, amorphous powder, free from gritty particles.
Solubility: Practically insoluble in water and in anhydrous ethanol.

A. Freezing point: minimum 53C, determined on the residue obtained in the preparation of solution S (see Tests).
B. Neutralise 5 mL of solution S to red litmus paper with strong sodium hydroxide solution. The solution gives the reaction of zinc.

Solution S: To 5.0 g add 50 mL of ether and 40 mL of a 7.5 per cent V/V solution of cadmium- and lead-free nitric acid in distilled water R. Heat under a reflux condenser until dissolution is complete. Allow to cool. In a separating funnel, separate the aqueous layer and shake the ether layer with 2 quantities, each of 4 mL, of distilled water. Combine the aqueous layers, wash with 15 mL of ether and heat on a water-bath until ether is completely eliminated. Allow to cool and dilute to 50 mL with distilled water (solution S). Evaporate the ether layer to dryness and dry the residue at 105C.
Appearance of solution: Solution S is not more intensely coloured than reference solution.
Appearance of solution of fatty acids: Dissolve 0.5 g of the residue obtained in the preparation of solution S in 10 mL of chloroform. The solution is clear and not more intensely coloured than reference solution5
Acidity or alkalinity: Shake 1.0 g with 5 mL of ethanol (96 per cent) and add 20 mL of carbon dioxide-free water and 0.1 mL of phenol red solution. Not more than 0.3 mL of 0.1 M hydrochloric acid or 0.1 mL of 0.1 M sodium hydroxide is required to change the colour of the indicator.
Acid value of the fatty acids: 195 to 210.
Chlorides: Maximum 250 ppm.
Sulfates: Maximum 0.6 per cent.
Cadmium: Maximum 5 ppm.
Lead: Maximum 25 ppm.

To 1.000 g add 50 mL of dilute acetic acid and boil for at least 10 min or until the layer of fatty acids is clear, adding more water as necessary to maintain the original volume. Cool and filter. Wash the filter and the flask with water until the washings are no longer acid to blue litmus paper. Combine the filtrate and washings. Carry out the complexometric titration of zinc.
1 mL of 0.1 M sodium edetate is equivalent to 6.54 mg of Zn.

Zinc Stearate SDS, Safety Data Sheet

MSDS Sheet, Material Safety Data Sheet

1. Product Identification

Product Name & Other Names: Zinc Stearate or Dibasic zinc stearate or stearic acid zinc salt or octadecanoic acid zinc salt or zinc distearate.
CAS No.: 557-05-1
EINECS EC Code: 209-151-9
Molecular Weight: 632.2
Chemical Formula: Zn(C18H35O2)2
Relevant uses and uses advised against (if any): Industrial Manufacturing.
Suppliers: As per letterhead.

2. Hazards Identification

GHS, Globally Harmonized System Classification in accordance with 29 CFR 1910
Classification according to Regulation (EC) No 1272/2008

Not a hazardous substance or mixture according to Regulation (EC) No. 1272/2008.
This substance is not classified as dangerous according to Directive 67/548/EEC.

Labeling according to GHS & Regulation (EC) No 1272/2008

GHS Label Elements

Signal Word: None

Hazards not otherwise classified (HNOC):
May form combustible dust concentrations in air.
May cause mild skin irritation.
May cause mild eye irritation.

Precautionary statements:
P261: Avoid breathing dust/fume/gas/mist/vapors/spray.
P262: Do not get in eyes, on skin, or on clothing.
P281: Use personal protective equipment as required.
P302+P352 - IF ON SKIN: Wash with plenty of soap and water.
P303+P361+P353 - IF ON SKIN (or hair): Remove/Take off immediately all contaminated clothing. Rinse skin with water/shower.
P304 + P340 - IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing.
P305 + P351 + P338 - IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P337+313: If eye irritation persists get medical advice/attention.

3. Composition/Information on Ingredients

Product Name & Other Names: Zinc Stearate or Dibasic zinc stearate or stearic acid zinc salt or octadecanoic acid zinc salt or zinc distearate.
CAS No. 557-05-1
EINECS EC Code: 209-151-9

4. First Aid Measures

Always seek medical attention after first aid measures are provided.

Inhalation: If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Call a physician.
Ingestion: Give several glasses of water to drink to dilute. If large amounts were swallowed, get medical advice.
Skin Contact: Wash exposed area with soap and water. Get medical advice if irritation develops.
Eye Contact: Check for and remove any contact lenses. Do not use an eye ointment. Seek medical attention.

5. Fire Fighting Measures

Fire: Flash point: 279C (534F)
Auto ignition temperature: 790C (1454F)
Minimum dust cloud ignition temperature is 690C (1274F). Contact with strong oxidizers may cause fire.
Explosion: Fine dust of Zinc stearate dispersed in air in sufficient concentrations, and in the presence of an ignition source is a potential dust explosion hazard. Minimum exposable concentration: 0.02 g/l (air). (Bureau of Mines, 1968). Maximum explosion pressure: 68 lb./sq. in. @ 0.3 ounces per cubic foot. Sensitive to static discharge.
Fire Extinguishing Media: Water spray, dry chemical, alcohol foam, or carbon dioxide. Water or foam may cause frothing.
Special Information In the event of a fire, wear full protective clothing and NIOSH-approved self-contained breathing apparatus with full face piece operated in the pressure demand or other positive pressure mode. At high temperatures under fire conditions, it may produce toxic or irritating fumes.

6. Accidental Release Measures

Personal precautions, protective equipment, and emergency procedures: Avoid breathing dust/fumes/gas/mist/vapors/spray. Use individual protective equipment (waterproof boots, suitable protective clothing, safety glasses, etc.). Restrict unprotected personnel from the area. Prevent any contact with hot surfaces. Do not approach facing the wind. Do not touch the spilled material.
Environmental precautions: Do not let the product enter drains, soil, or water sources.
Methods and materials used for containment Cleanup procedures and Storage:
Small Spill: Use appropriate tools to put the spilled solid in a convenient waste disposal container. Finish cleaning by spreading water on the contaminated surface and dispose of according to legal requirements.
Large Spill: Do not inhale dust, vapors, mist, or gas. Avoid dust formation. Contain spilled material. Cover with an inert, non-combustible absorbent material, (e.g. sand, earth, diatomaceous earth, vermiculite). Use a shovel to put the material into a convenient waste disposal container. Finish cleaning by spreading water on the contaminated surface and allow to evacuate as per law.

7. Handling and Storage

Precautions for safe handling: Apply according to good manufacturing and industrial hygiene practices. Ensure proper ventilation. In case of insufficient ventilation, wear suitable respiratory equipment. Wash thoroughly after handling. Do not drink, eat, or smoke while handling. Avoid contact with skin, eyes, and clothing. Minimize dust generation. Avoid breathing dust/fumes/gas/mist/vapors/spray. Avoid contact with eyes, skin, and clothing. Keep container tightly closed. Avoid ingestion and inhalation. Use individual protective equipment (waterproof boots, suitable protective clothing, safety glasses, etc.). Prevent any contact with hot surfaces.
Conditions for safe storage, including any incompatibilities: Store in cool, dry, and ventilated area away from heat sources and protected from sunlight in tightly closed original container. Keep air contact to a minimum. Store protected from heat, sparks and ignition sources and incompatible materials. Avoid contact with skin and eyes. Avoid inhalation of dust/mist/vapor. Do not store with incompatible materials like strong oxidizing agents, strong alkalis, peroxides, oxygen, and acids. Ground all equipment containing material and protect from static discharge.

8. Exposure Controls/Personal Protection

Airborne Exposure Limits:
-OSHA Permissible Exposure Limit (PEL):
15 mg/m3 total dust, 5 mg/m3 respirable fraction for zinc stearate
-ACGIH Threshold Limit Value (TLV):
10 mg/m3 total dust for stearate (does not include stearate of toxic metals)
Ventilation System:
A system of local and/or general exhaust is recommended to keep employee exposures below the Airborne Exposure Limits. Local exhaust ventilation is generally preferred because it can control the emissions of the contaminant at its source, preventing dispersion of it into the general work area. Please refer to the ACGIH document, Industrial Ventilation, A Manual of Recommended Practices, most recent edition, for details.
Personal Respirators (NIOSH Approved): If the exposure limit is exceeded and engineering controls are not feasible, a half face piece particulate respirator (NIOSH type N95 or better filters) may be worn for up to ten times the exposure limit or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. A full-face piece particulate respirator (NIOSH type N100 filters) may be worn up to 50 times the exposure limit, or the maximum use concentration specified by the appropriate regulatory agency, or respirator supplier, whichever is lowest. If oil particles (e.g. lubricants, cutting fluids, glycerin, etc.) are present, use a NIOSH type R or P filter. For emergencies or instances where the exposure levels are not known, use a full-face piece positive-pressure, air-supplied respirator. WARNING: Air-purifying respirators do not protect workers in oxygen-deficient atmospheres.
Skin Protection: Gloves and lab coat, apron, or coveralls.
Eye Protection: Use chemical safety goggles.
Other Control Measures: Maintain good housekeeping in work area. Handle in accordance with good industrial hygiene and safety practice.

9. Physical and Chemical Properties

Appearance: fine, soft white powder, granules, prills or flakes.
Odor: Slight odor of fatty acid.
Odor threshold: Not available.
pH: Not available.
Relative density: around 1.095
Boiling Point: Decomposes.
Melting Point: 120 - 130C (248 - 266F).
Flash point: Not available.
Auto-ignition temperature: Not available.
Decomposition temperature: Not available.
Upper/lower flammability or explosive limits: Not available.
Vapor pressure: Not available.
Vapor density: Not available.
Evaporation rate: Not available.
Flammability (solid, gas): Not available.
Partition coefficient: n-octanol/water: Not available.
Solubility: Insoluble in water, alcohol, ether; slightly soluble in benzene.
Viscosity: Not available.

10. Stability and Reactivity

Stability: Stable under ordinary conditions of use and storage.
Hazardous Decomposition Products: Burning may produce carbon monoxide, carbon dioxide, and zinc oxides.
Hazardous Polymerization: Will not occur.
Incompatibilities: Strong oxidizers, strong alkalis, peroxides, oxygen, and acids.
Conditions to Avoid: Heat, flames, ignition sources and incompatibles.
Molecular Weight: 632.2
Chemical Formula: Zn(C18H35O2)2

11. Toxicological Information

LD50 oral, rat = > 10 gm/Kg.
Carcinogenicity: No component of this product present at levels greater than or equal to 0.1% is identified as probable or confirmed human carcinogen by IARC, ACGIH, OSHA and NTP.
Results of PBT and vPvB assessment: This substance/mixture contains no components considered to be either persistent, bioaccumulative and toxic (PBT), or very persistent and very bioaccumulative (vPvB) at levels of 0.1% or higher.

12. Ecological Information

Toxicity to fish: No information available.
Persistence and Degradability: No information available.
Mobility: No information available.
Bioaccumulation/ Accumulation: No information available.
Results of PBT and vPvB assessment: No data available for assessment.

13. Disposal Considerations

Whatever cannot be saved for recovery or recycling should be managed in an appropriate and approved waste disposal facility. Processing use or contamination of this product may change the waste management options. State and local disposal regulations may differ from federal disposal regulations. Dispose Zinc stearate container and unused contents in accordance with law.

14. Transport Information

DOT (USA) & ADR/RID: Not dangerous goods.
TDG/IMDG & IATA: Not dangerous goods.

15. Regulatory Information

USA Regulations:
SARA 311/312: See section 2.
SARA 313 toxic chemical notification and release reporting: Zinc stearate.

Section 16 - Additional Information

DISCLAIMER: The information and recommendations set forth herein (hereinafter "Information") are presented in good faith and believed correct as of the date hereof. It is compiled from various sources and it is not necessarily all inclusive nor fully adequate in every circumstance. In addition, these suggestions should not be confused with nor followed in violation of applicable laws, regulations, rules or insurance requirements applicable. This MSDS sheet is intended only as a guide to the appropriate precautionary handling of the material by a properly trained person using this product. Individuals receiving the information must exercise their independent judgment in determining its appropriateness for a particular purpose.