Dodecyl trimethyl ammonium chloride
[CAS# 112-00-5]

Identification

• Classification: Surfactant >> Cationic surfactant >> Quaternary ammonium salt type
• Name: Dodecyl trimethyl ammonium chloride
• Synonyms: Dodecyltrimethylammonium chloride; N,N,N-Trimethyl-1-dodecanaminium chloride; Trimethyl-1-dodecanaminium chloride; Lauryl trimethyl ammonium chloride; Laurtrimonium chloride
• Molecular Formula: C₁₅H₃₄N^.Cl
• Molecular Weight: 263.89
• CAS Registry Number: 112-00-5
• EC Number: 203-927-0
• SMILES: CCCCCCCCCCCC[N+](C)(C)C.[Cl-]

Properties

• Melting point: 237 ºC
• Water solubility: Soluble

Safety Data

• Hazard Symbols: GHS05;GHS07;GHS09 Danger
• Hazard Statements: H302-H314-H315-H318-H319-H335-H400-H410-H411
• Precautionary Statements: P260-P261-P264-P264+P265-P270-P271-P273-P280-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P351+P338-P305+P354+P338-P316-P317-P319-P321-P330-P332+P317-P337+P317-P362+P364-P363-P391-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Serious eye damage	Eye Dam.	1	H318
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Skin corrosion	Skin Corr.	1B	H314
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Skin corrosion	Skin Corr.	1C	H314
Skin corrosion	Skin Corr.	1A	H314
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	3	H301

• Transport Information: UN 3077

Discovory and Applicatios

Dodecyl trimethyl ammonium chloride is a quaternary ammonium compound that has been widely used as a cationic surfactant and biocide. Its chemical structure consists of a quaternary nitrogen atom bonded to a dodecyl (C₁₂) alkyl chain and three methyl groups, with chloride as the counterion. The compound was first developed during the 20th century as part of a broader effort to create surfactants that combined surface-active properties with antimicrobial activity. Quaternary ammonium compounds like dodecyl trimethyl ammonium chloride were found to disrupt microbial cell membranes, causing leakage of cellular contents and rapid cell death. This antimicrobial mechanism made them suitable for applications in sanitation and disinfection.

In industrial and household settings, dodecyl trimethyl ammonium chloride has been applied in disinfectants, sanitizers, and cleaning products. Its ability to reduce surface tension allows it to penetrate and remove soils while simultaneously providing antimicrobial protection. It has been used in formulations for hard surface cleaning, water treatment, and in healthcare environments where control of bacterial and fungal contamination is critical. Its broad-spectrum activity against Gram-positive and Gram-negative bacteria, as well as certain fungi, contributes to its effectiveness in these applications.

The compound also finds use in personal care products, particularly in hair conditioners, shampoos, and other formulations where cationic surfactants improve wet combing, reduce static, and impart softness. The long dodecyl chain adheres to negatively charged surfaces such as hair or skin, while the cationic head reduces friction and improves manageability. In textile and fabric care, it is incorporated into fabric softeners and antistatic treatments, where it binds to fibers, reducing static cling and increasing softness and durability.

Dodecyl trimethyl ammonium chloride has been used as a phase transfer catalyst in organic synthesis due to its amphiphilic structure, allowing efficient transport of reactants between aqueous and organic phases. Its chemical stability under a wide range of pH conditions and temperatures makes it suitable for industrial-scale chemical processes. Additionally, it has applications in emulsions and dispersions, helping to stabilize formulations that include both hydrophobic and hydrophilic components.

Environmental and safety considerations have influenced the use of dodecyl trimethyl ammonium chloride. As with other quaternary ammonium compounds, it can be toxic to aquatic organisms and exhibits persistence in wastewater if not properly treated. Regulatory guidelines specify concentrations and disposal methods to mitigate environmental impact. Occupational exposure is generally controlled through standard safety practices, as the compound can cause skin or eye irritation at higher concentrations.

The development and widespread adoption of dodecyl trimethyl ammonium chloride highlight the balance between chemical functionality and safety in surfactant chemistry. Its discovery as a member of the quaternary ammonium class of compounds enabled a range of industrial, household, and personal care applications, providing effective antimicrobial action, conditioning, and antistatic properties. Over time, it has become a key ingredient in products that require the combination of surface activity, microbial control, and material conditioning, illustrating the versatility and enduring relevance of quaternary ammonium chemistry.

References

2025. Flotation Reagents of Tungsten Ore. Flotation Chemistry of Tungsten Minerals and Its Application.
DOI: 10.1007/978-981-96-5077-4_5

2025. Synthesis and Characterization of Surfactant-Modified Clays for Adsorption Applications. Characterization of Minerals, Metals, and Materials 2025.
DOI: 10.1007/978-3-031-80680-3_46

2024. Fouling-resistant reverse osmosis membranes grafted with 2-aminoethanethiol having a low interaction energy with charged foulants. npj Clean Water, 7(1).
DOI: 10.1038/s41545-024-00326-5