Didecyl Dimethyl Ammonium Chloride (DDAC)

Didecyl Dimethyl Ammonium Chloride (DDAC) – Broad-Spectrum Quaternary Ammonium Disinfectant and Surfactant

Basic Information

• CAS Number: 7173-51-5

• Molecular Formula: C₂₂H₄₈ClN

• Molecular Weight: 362.08–364.0 g/mol

• Synonyms: Didecyldimethylammonium chloride, DDAC

• Appearance: Colorless to pale yellow liquid (typically supplied as aqueous solution)

• Solubility: Highly soluble in water and alcohols; insoluble in non‑polar solvents

• Storage: Store in tightly sealed containers at 5–30°C, protected from light and moisture

• Stability: Stable at pH 5–9; sensitive to strong alkaline conditions

Overview
Didecyl dimethyl ammonium chloride (DDAC) is a well‑established cationic quaternary ammonium compound featuring two decyl (C10) hydrophobic chains. This structure provides excellent surface activity, broad‑spectrum antimicrobial efficacy, and good water solubility. DDAC is widely used as a disinfectant, sanitizer, and preservative in healthcare, food processing, agriculture, and industrial applications. Its rapid action against bacteria, fungi, algae, and some viruses, combined with low toxicity at recommended concentrations, makes it a versatile and reliable biocide.

Applications

• Healthcare and sanitation: Used in surface disinfectants, instrument sterilizers, and hand sanitizers in hospitals, clinics, and veterinary settings.

• Food processing: Applied in CIP (clean‑in‑place) systems, equipment sanitation, and food contact surface disinfection.

• Agriculture: Used for disinfection of animal housing, poultry farms, and crop protection (as a fungicide and bactericide).

• Water treatment: Employed as a biocide in cooling towers, swimming pools, and industrial water systems.

• Household cleaning: Incorporated into all‑purpose cleaners, floor disinfectants, and bathroom products.

• Industrial: Used as a preservative in paints, adhesives, and metalworking fluids.

Mechanism of Action
DDAC disrupts microbial cell membranes through electrostatic interaction with negatively charged phospholipid bilayers, leading to leakage of intracellular components and cell lysis. It also denatures proteins and enzymes, contributing to rapid bactericidal, fungicidal, and algicidal effects.

Key Benefits

• Broad‑spectrum antimicrobial activity (bacteria, fungi, algae, viruses).

• Effective at low concentrations (0.01–0.5%).

• Good water solubility and compatibility with other cationic and non‑ionic surfactants.

• Stable over a wide pH range (5–9).

• Non‑corrosive and non‑staining at recommended use levels.

• Cost‑effective and widely available.

Safety and Handling

• May cause mild skin and eye irritation at high concentrations; use appropriate personal protective equipment (gloves, safety goggles) when handling.

• Incompatible with anionic surfactants – forms precipitates.

• Avoid contact with strong oxidizers and acids.

• Store in a cool, dry place, away from direct sunlight.

• Shelf life: typically 24 months under recommended storage conditions.

Quality Assurance
Each batch is tested for active content, pH, and antimicrobial efficacy to ensure consistent quality.