Buying Sodium Laureth Sulfate (SLES): What Matters
Sodium laureth sulfate (SLES) is a high-volume commodity surfactant, but the differences between suppliers show up in the parameters that consumers never see: colour, active content, inorganic sulfate, unsulfated matter and the trace impurity 1,4-dioxane. Buying well means specifying those parameters and confirming the grade fits your product and market.
For the chemistry behind these points, see our main article on sodium laureth sulfate (SLES, CAS 9004-82-4).
Step 1: Confirm the Identity and Grade
| Item | What to confirm |
|---|---|
| Substance | Sodium laureth sulfate (CAS 9004-82-4, also 68585-34-2) |
| Ethoxylation | The EO number (e.g. 2EO), which sets mildness |
| Active content | 70 ± 2% for the standard paste |
Do not confuse it with SLS (CAS 151-21-3), which is not ethoxylated and is a different, more irritating surfactant.
Step 2: Read the Specification
| Parameter | Why it matters | Typical value |
|---|---|---|
| Active matter | Dosing and cost per active unit | 70 ± 2% |
| Appearance | Confirms a clean paste | White to yellowish paste |
| Colour (5% A.M.), Hazen | White/clear finished products | ≤ 20 |
| Sodium sulfate | Process efficiency; formulation effect | ≤ 2.0% |
| Unsulfated matter | Process efficiency; performance | ≤ 3.0% |
| pH (25 °C) | Stability and skin compatibility | 7.0 – 10.0 |
| 1,4-Dioxane | Controlled impurity; critical for cosmetics | Per customer/regulatory limit |
The two parameters that most often decide a purchase are colour (for white/clear products) and the 1,4-dioxane level (for regulated personal-care use).
Step 3: Check the Impurity That Matters Most
1,4-Dioxane is a possible by-product of ethoxylation and is regulated or tightly limited in cosmetics and personal-care products. Buying SLES without confirming the dioxane level is a quality risk.
- Ask for the 1,4-dioxane figure and the test method.
- Match the grade to your market’s limit and your brand’s claims.
- Prefer suppliers who run a controlled ethoxylation process (and, where necessary, a stripping step) to keep dioxane low.
Step 4: Form, Packaging and Handling
- Form. The 70% paste is standard; it may thicken in the cold, so plan to warm and mix.
- Packaging. 200 kg drums and 1000 kg IBCs are typical; keep sealed and use corrosion-resistant equipment.
- Cationic incompatibility. Keep SLES away from cationic surfactants and polymers in the same phase.
- Storage. Cool, dry and out of direct sunlight; rotate stock.
Supplier Checklist
- Identity and EO. CAS 9004-82-4 and the correct ethoxylation confirmed.
- Active content. 70% (or as specified).
- Colour. Low Hazen for clear/white products.
- 1,4-Dioxane. Stated and within your limit.
- Documentation. SDS, per-batch COA and cosmetic/regulatory statements.
- Consistency. Batch history if colour or dioxane is critical.
Common Buying Mistakes
- Confusing SLES with SLS. Different CAS and different performance; confirm the CAS.
- Buying on active content alone. Colour and dioxane distinguish good from adequate SLES.
- Ignoring dioxane. Cosmetic and personal-care use requires a controlled level.
- Mixing with cationics. Using SLES with cationic ingredients in the same phase wastes both.
- Poor storage. The paste thickens in the cold and can change consistency over long storage.
How PolyBlueChem Can Help
PolyBlueChem can supply SLES 70% (CAS 9004-82-4, also 68585-34-2), with the documentation appropriate to your application. To request current specifications, a COA or a quotation, contact the PolyBlueChem team.
Frequently Asked Questions
What should I look for when buying SLES?
Confirm the identity (CAS 9004-82-4) and ethoxylation, check active content and colour, require the 1,4-dioxane level, and secure the SDS, COA and cosmetic statements.
Why is 1,4-dioxane important?
It is a controlled by-product of ethoxylation; cosmetics need low-dioxane SLES that meets the market’s limit.
What is the standard active content?
70 ± 2% for the standard paste grade; other strengths are available.
Is SLES the same as SLS?
No. SLES (9004-82-4) is ethoxylated and milder; SLS (151-21-3) is not ethoxylated.
How should SLES be stored?
Sealed, cool and out of direct sunlight; warm and mix the paste before use.