Cetrimonium Chloride 1631 (CTAC)

Cetrimonium Chloride 1631 (Cetyltrimethylammonium Chloride): Properties and Applications

1. Introduction

Cetrimonium chloride 1631, widely known as cetyltrimethylammonium chloride (CTAC), is a cationic surfactant belonging to the quaternary ammonium compound group. It combines antiseptic and conditioning functions, making it popular in various industries – from cosmetics to medical disinfectants.

2. Chemical Structure and Nomenclature

Chemical name: Cetyltrimethylammonium chloride; Hexadecyltrimethylammonium chloride

Molecular formula: C₁₉H₄₂ClN

Molecular weight: 320.0 g/mol

CAS number: 112-02-7

EC number: 203-928-6

Appearance: White to off-white powder, flakes, or 25–30% aqueous solution

3. Physicochemical Properties

Solubility: Soluble in water and alcohols, forming cationic ions.

Surface activity: Reduces surface tension, stabilizes emulsions, and acts as a conditioning agent in hair care products.

Antiseptic activity: The cationic head group interacts with negatively charged microbial membranes, causing structural disruption and cell death. Active against a wide range of bacteria and some fungi.

Antistatic effect: Neutralizes static charges on hair and fabrics, improving tactile properties.

4. Applications

Cosmetics: Used in shampoos, conditioners, and hair masks to reduce frizz, add softness, and ease combing. Also used in creams and lotions as an emulsion stabilizer and antimicrobial agent.

Medicine and pharmaceuticals: Used in antiseptic and disinfectant solutions for surface and skin treatment. Occasionally used in ophthalmic preparations at controlled concentrations.

Textile and household chemicals: Used for antistatic treatment of fabrics, aiding dyeing processes. Incorporated into cleaning products for antibacterial effects and static reduction.

5. Safety and Toxicology

Skin irritation: At recommended concentrations (0.1–2% in hair care), irritation is minimal. Higher concentrations may cause redness, burning, or allergic reactions.

Systemic toxicity: Limited skin penetration; systemic effects unlikely. Accidental ingestion may cause nausea and gastrointestinal discomfort.

Biodegradability: Cationic surfactants generally degrade less readily than anionic ones; however, modern formulations aim to improve environmental compatibility. Wastewater discharge should be monitored.

6. Regulatory Status

Cosmetics: Approved in the EU, US, and Asian countries with concentration limits (typically up to 5% in leave-on products, up to 10% in rinse-off products).

Pharmaceuticals: Listed in pharmacopoeias (USP, Ph. Eur.) with specified purity criteria.

Safety Data Sheets (SDS): Required for industrial handling, detailing precautions, storage, and disposal.

7. Advantages and Limitations

Advantages: Combines conditioning, antistatic, and antimicrobial properties. Good compatibility with non-ionic and some amphoteric surfactants. Stable over a wide pH range.

Limitations: Incompatible with anionic surfactants (precipitates). May cause skin and eye irritation at high concentrations.

8. Research and Development Trends

Milder cationic surfactants: Research on structural modifications to reduce irritation and improve biodegradability.

Combination formulations: CTAC combined with natural extracts and phospholipids for enhanced cleansing, antiseptic, and conditioning effects.

Antimicrobial resistance: Monitoring microbial resistance to QACs remains important; resistance is currently low but requires systematic observation.

9. Conclusion

Cetrimonium chloride 1631 (CTAC) is a versatile cationic surfactant valued for its conditioning, antistatic, and antiseptic properties. It is widely used in hair care, household and medical disinfection, and textile processing. When used within recommended concentrations and proper formulations, it is effective and safe for consumers. Ongoing research focuses on improving its environmental profile and physiological compatibility.