Magnesium Dodecyl Sulfate
Time: 2012-09-07 15:52:41
Magnesium Dodecyl Sulfate
Synonyms
Magnesium Lauryl Sulfate;
Sulfuric Acid Monododecyl Ester Magnesium Salt;
Category
Anionic Surfactant
>> Sulfate
>> Chain Alcohol Sulfate
>> Alkanol Sulfate
>> Linear Alkanol Sulfate
Chemical Numbering System
CASRN: 3097-08-3
EINECS: 221-450-6
Molecular Formula & Molecular Weight
Molecular Formula: C24H50MgO8S2; C24H52O8S2.Mg (SciFinder Hill Rules)
Molecular Weight: 555.08
Structure
Properties
Appearance    (1), slightly yellow liquid; (2), solid powder.
Odor    faint characteristic odor.
Solubility    soluble in water.
Hygroscopicity    Solid magnesium dodecyl sulfate: hygroscopic.
Physical - chemical properties
Flash point, °C
> 93
Stability    stable in alkali, weak acid and hard water; unstable in strong acid, hydrolyzed, reduced to alcohol.
Risk    Solid form: flammable material; irritation, irritation to skin, eye, respiratory. Harmful products of combustion are CO, CO2 and so on. Contact with strong oxidants, can cause to burn.
GHS (Rev.6) label:  
Liquid form: irritation, irritation to skin, eye.
GHS (Rev.6) label:
Ecology    may be hazardous to environment. Water body should be given special attention.
Biodegradability    biodegradable.
Characteristics    excellent cleansing, foaming, emulsifying, wetting, permeating, dispersing, solubilizing, antistatic abilities. Mild. Resistant to hard water. Strongly resistant to electrolyte.
Note    (1), Avoid using in children products that can be direct prolonged contact with the skin, such as: skin care products.
Synthesis
Currently, sulfated reaction through continuous reactor (such as: falling film reactor) is the most widely used method for preparing sulfates.
Generally, dodecyl alcohol and sulfur trioxide react through reactor, then magnesium 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 alcohols or other raw materials: 1:1; temperature: 30-60°C; reactor: falling film reactor.
US patent 6,455,488 (Process of making alkyl sulfate granulates) describes the preparation of a particulate alkyl sulfate, but does not involve the synthesis process.
US patent US 6,331,645 (Process for preparing powdery alkyl sulfates) describes the preparation of a powdery alkyl sulfate, but does not involve the synthesis process.
Quality Standards & Test Methods
1. Physical and chemical indexes
Item
Physical and chemical indexes
Liquid
Actives, %, ≥
25-30
Unsulfated materials, %, ≤
2.5
MgSO4, %, ≤
0.75
MgCl2, %, ≤
0.3
pH (25°C, 10% solution)
6.5-7.5
Color, Gardner, ≤
2
Density, g/mL, approx.
1.02
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), Unsulfated materials
GB/T 11989 Anionic surface active agents - Determination of soluble matter content in light petroleum
ISO 894 Surface active agents -- Technical sodium primary alkylsulphates -- Methods of analysis
(3), MgSO4
GB/T 15963 Sodium lauryl sulfate, magnesium sulfate calculated.
ISO 894 Surface active agents -- Technical sodium primary alkylsulphates -- Methods of analysis
(4), MgCl2
GB/T 15963 Sodium lauryl sulfate, magnesium chloride calculated.
ISO 894 Surface active agents -- Technical sodium primary alkylsulphates -- Methods of analysis
(5), 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
(6), Color (Gardner)
GB/T 22295 Standard test method for color of transparent liquids (Gardner Color Scale)
ISO 4630 Clear liquids -- Estimation of colour by the Gardner colour scale
(7), Density
GB/T 4472 Determination of density and relative density for chemical products
ISO 758 Liquid chemical products for industrial use -- Determination of density at 20 degrees C
2. Hazardous substances indexes
Item
Hazardous substances indexes
Liquid
Heavy metals (as Pb), mg/Kg, ≤
20
As, mg/Kg, ≤
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. Standards
(1), Chinese standards
National drug standards: WS-10001-(HD-0398)-2002 Magnesium Lauryl Sulfate
4. Further explanation
(a), On physical and chemical indexes: firstly, shall be indicated carbon atom distribution; secondly, shall be indicated average molecular weight.
Major Uses
1. Personal care products
Cleansing agent, foaming agent in personal care products.
For example, main ingredient or auxiliary ingredient for cleansing agent, foaming agent in shampoo, hand sanitizer, bubble bath, bath soap and other products.
2. Household detergents
Main ingredient or auxiliary ingredient for cleansing agent, foaming agent in dishwasher cleaning agent, carpet cleaning agent and other household products.
3. Industrial cleaning agents
Main ingredient or auxiliary ingredient for cleansing agent, foaming agent.
4. Pets
Main ingredient or auxiliary ingredient for cleansing agent, foaming agent in shampoos and other pet products.
5. Medicine
Lubricant, disintegrating agent, emulsifying agent in medicine, such as: tablets, powders, creams.
Lubrication of magnesium lauryl sulfate is weaker than magnesium stearate, stronger than talcum powder, polyethylene glycol and sodium lauryl sulfate.
Adverse effect on tablet hardness of magnesium lauryl sulfate is less than magnesium stearate.
As a disintegrating agent, magnesium lauryl sulfate outperforms stearate.
Applications in pharmaceutical industry, further see: United States Patent 3,976,601 Water soluble lubricant for tabletting compositions, etc.
6. Emulsion polymerization
Emulsifier, particle size controlling agent in emulsion polymerization. For example, polyvinyl chloride emulsion polymerization.
7. Textile, leather
Use as emulsifier, foaming agent, cleansing agent, wetting agent, antistatic agent, solubilizing agent.
8. Disinfectant
Use as foaming agent, retention agent.
For example, United States Patent 6,828,294 describes high retention sanitizer systems.
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More applications for magnesium lauryl sulfate, further see: United States Patent 7,208,144 Stabilized dispersion of behenyl alcohol, United States Patent 4,354,872 Metal oxide oil slurries, etc.
Manufacturers
 
Update: 20131018(1); 20160728(2);