Diethylene Glycol Monolauryl Ether Sodium Sulfate
Synonyms
Sodium Laureth-2 Sulfate;
PEG-2 Lauryl ether sulfate, sodium salt;
Polyethylene glycol (2) lauryl ether sulfate, sodium salt;
Polyoxyethylene (2) lauryl ether sulfate, sodium salt;
Sodium polyethylene glycol (2) lauryl ether sulfate;
SLES;
Category
Anionic Surfactant
> Sulfate
>> Alcohol Polyether Sulfate
>>> Alcohol Polyoxyethylene Ether Sulfate
>>>> Linear Alkanol Polyoxyethylene Ether Sulfate
Chemical Numbering System
CAS: 3088-31-1
EINECS: 221-416-0
Molecular Formula & Molecular Weight
Molecular Formula: C16H33NaO6S; C16H34O6S.Na
Molecular Weight: 376.48
Structure
Properties
Appearance (1), paste; (2), liquid; (3), solid..
Odor faint characteristic odor.
Solubility soluble in water.
Stability stable in alkali, weak acid and hard water; unstable in strong acid, easily hydrolyzes.
Risk Liquid (or paste) form: irritation, irritation to skin, eye. Irritation of sodium laureth-2 sulfate is lower than sodium dodecyl sulfate.
GHS label: 
Ecology may be hazardous to environment. Water body should be given special attention.
Biodegradability biodegradable.
Characteristics excellent cleansing, foaming, emulsifying, wetting, dispersing, solubilizing, foam stabilizing abilities. Resistant to hard water.
Note (1), Products that has low content of 1,4-dioxane can be used in children cleaning products. Based on irritating judgment, usage should not exceed to 10%. In no tears formula of children shampoo, may be difficult to use as a primary surfactant.
(2), 1,4-dioxane generated during preparation: probable carcinogen. However, can be acceptable when concentration of 1,4-dioxane is less than 30ppm or less.
Synthesis
Currently, sulfated reaction through continuous reactor (such as: falling film reactor) is the most widely used method for preparing sulfates.
1, Synthesis of polyether
Obtain by polymerization reaction of lauryl alcohol and ethylene oxide.
For further information, see:
US patent 4,223,163 Process for making ethoxylated fatty alcohols with narrow polyethoxy chain distribution; US patent 4,967,017 Alcohol ethoxylates of reduced EO content or residual PO content; US patent 5,069,817 Process for making polyoxyethylene surfactants with desirable low temperature behavior etc.
2, Synthesis of sulfate
Lauryl alcohol polyoxyethylene ether and sulfur trioxide react through reactor, then sodium hydroxide neutralizes, finally obtain product.
US patent 8,921,588 (Process for preparing sulfates and/or sulfonates in a micro-reaction system) presents a synthetic process. Conditions: mole ratio of sulfur trioxide and polyethers or other raw materials: 1:1; temperature: 30-60°C; reactor: falling film reactor.
Quality Standards & Test Methods
1, Physical and chemical indexes
|
Item |
Physical and chemical indexes |
|
|
High-enriched type |
Low-enriched type |
|
|
Actives, %, ≥ |
60.0 - 72.0 |
25.0 - 30.0 |
|
pH (25°C, 1% solution) |
6.5 - 9.5 |
6.5 - 9.5 |
|
1,4-Dioxane, ppm, ≤ |
30 |
30 |
Test Methods
(1), Actives
GB/T 5173 Surface active agents and detergents -- Determination of anionic-active matter by direct two-phase titration procedure
ISO 2271 Surface active agents -- Detergents -- Determination of anionic-active matter by manual or mechanical direct two-phase titration procedure
(2), pH
GB/T 6368 Surface active agents -- Determination of pH of aqueous solution - Potentiometric method
ISO 4316 Surface active agents -- Determination of pH of aqueous solutions -- Potentiometric method
(3), 1,4-Dioxane
GB/T 26388 Determination of dioxane residues in surfactants - Gas chromatographic method
ISO 17280 Surface active agents -- Determination of 1,4-dioxan residues in surfactants obtained from epoxyethane by gas chromatography
2, Hazardous substances indexes
|
Item |
Hazardous substances indexes |
|
|
High-enriched type |
Low-enriched type |
|
|
Heavy metals (as Pb), mg/kg, ≤ |
20 |
20 |
|
As, mg/kg, ≤ |
3 |
3 |
Test Methods
(1), Heavy metals (as Pb)
Safety and Technical Standards for Cosmetics (2015 Edition)
GB/T 30799 The test method of food detergents -- Determination of heavy metals
(2), As
Safety and Technical Standards for Cosmetics (2015 Edition)
GB/T 30797 The test method of food detergents -- Determination of total arsenic
3, Further explanation
(a), On physical and chemical indexes: firstly, shall be indicated carbon atom distribution; secondly, shall be indicated average molecular weight.
(b), Used in cosmetics, should be test for harmful substances; or furtherly test for microorganisms.
Major Uses
1, Typical applications
Use as cleansing agent.
Use as emulsifying agent, dispersing agent.
Use as foam stabilizing agent, foaming agent.
Use as solubilizing agent.
2, Personal care products
Cleansing agent, foaming agent, emulsifying agent in personal care products.
For example, main ingredient or auxiliary ingredient for cleansing agent, foaming agent in shampoo, hand sanitizer and other products.
The products that contact with the skin for a long time, not recommended to use.
3, Household detergents
Main ingredient or auxiliary ingredient for cleansing agent, foaming agent in laundry detergent, hard surface detergent and other household products.
Particularly, suitable for the preparation of high bubble and light-duty detergents.
4, Food-related industries
Main ingredient or auxiliary ingredient for cleansing agent, foaming agent in dishwashing detergent, fruit and vegetable cleaning agent and other products.
5, Industrial cleaning agents
Main ingredient or auxiliary ingredient for cleansing agent, foaming agent in car cleaning products, metal cleaning products and other industrial cleaning products.
Particularly, suitable for the preparation of high bubble detergents, for example: car cleaning agents.
6, Emulsion polymerization
Emulsifier, particle size controlling agent in emulsion polymerization.
7, Textile, leather
Use as emulsifier, foaming agent, cleansing agent, solubilizing agent.
8, Pets
Main ingredient or auxiliary ingredient for cleansing agent, foaming agent in shampoos and other pet products.
Manufacturers
Update: 20131018(1); 20161122(2);