Steareth-21

CAS Number:

9005-00-9

Chemical Name: 

Steareth-21. Also known as Polyoxyethylene (21) stearyl ether, PEG-21 stearyl alcohol .

Brand Name:

 SABOWAX ST 21 PL MB (manufactured by SABO S.p.A)

Molecular Formula:

Complex mixture, derived from ethoxylation of stearyl alcohol with average 21 moles of ethylene oxide (C18H38O·(C2H4O)n·H where n ≈ 21)

Molecular Weight:

Varies by exact ethoxylation distribution

EC Number:

500-017-8

Common Form:

White waxy solid in flakes ; white, waxy compound

Uses:

Steareth-21 is a non-ionic emulsifier and surfactant derived from stearyl alcohol ethoxylated with an average of 21 moles of ethylene oxide . It is widely used in cosmetic and personal care formulations for its excellent emulsifying and solubilizing properties .

Primary Applications :

· Skin Care Products: Used in day creams, night creams, hand creams, lotions, and self-tanning lotions .

· Hair Care Products: Incorporated into hair conditioners and lotions .

· Antiperspirants & Deodorants: Suitable for antiperspirants, deodorants, and roll-on deodorant formulations .

· Depilatory Products: Used in depilatory creams .

· Color Cosmetics: Used in makeup products including foundations .

· Sun Care: Suitable for suntan products and sunscreen formulations .

· Cleansing Products: Functions as a cleansing agent in shampoos, shower gels, and face washes .

· Oxidative Cream Formulations: Suitable for oxidative cream systems .

What does Steareth-21 / SABOWAX ST 21 PL MB do in a formulation?

• O/W Emulsifier: Primary function. Allows the formation of finely dispersed oil-in-water emulsions by reducing interfacial tension between oil and water, creating stable mixtures . It is a non-ionic emulsifier compatible with anionic, cationic, and non-ionic surfactants.
• Solubilizer: Helps dissolve poorly water-soluble substances (such as fragrances, essential oils, and active ingredients) into aqueous systems.
• Surfactant: Reduces surface tension of formulations, contributing to even distribution of products during use . Functions as a wetting agent with good wetting properties.
• Cleansing Agent: Cleans skin, hair, or teeth by helping water mix with oil and dirt.
• Dispersant: Acts as a dispersing agent in formulations.
• Coupling Agent: Functions as a coupling agent to harmonize different components in formulations.
• Foam Modifier: Influences foam characteristics in cleansing products.

Safety Profile:

· Safety Assessment: In 2012, the independent Cosmetic Ingredient Review (CIR) panel ruled that Steareth-21 is safe as used in cosmetics in amounts up to 7% .

· Toxicity Profile: PEG derivatives with varying molecular weights have been repeatedly evaluated and considered relatively safe for cosmetic use .

· Contamination Concerns: Important Note: There have been concerns about the safety of steareth ingredients because toxic 1,4-dioxane, a by-product of ethoxylation, can potentially be produced; however, this is eliminated through rigorous purification processes in high-quality products .

· Skin/Eye Contact: Generally non-irritating at typical use concentrations in finished formulations.

· Inhalation: Powder dust may cause respiratory tract irritation. Avoid dust inhalation during manufacturing.

· Environmental Impact: Biodegradable and complies with clean beauty standards including Clean at Sephora and Ulta Beauty's Conscious Beauty . No evidence of bioaccumulation potential.

· Required PPE: Safety glasses, chemical-resistant gloves, and dust mask when handling raw material in manufacturing settings.

· Storage and Handling Note: Store in a cool, dry place away from direct sunlight and moisture. Keep container tightly closed. Shelf life: 48 months when stored properly .

· Certifications & Compliance :

  · REACH Exempt (Europe)

  · RSPO MassBalance Certified

  · AICS, ECL, DSL, IECSC, ISHL, EC compliant

  · Gluten-free, BSE/TSE-free, GMO-free, VOC-free

Technical profile: