Poly(hexamethylenebiguanide) hydrochloride (PHMB) CAS 27083-27-8

Introduction to PHMB

Poly(hexamethylenebiguanide) Hydrochloride is a cationic polymeric biocide built on repeating hexamethylene biguanide hydrochloride units. Positively charged biguanide groups rapidly adsorb onto negatively charged microbial cell membranes, disrupting membrane permeability, causing intracellular component leakage and inhibiting key enzyme systems. It delivers broad-spectrum efficacy against bacteria, fungi and algae, with high activity at low concentrations and good long-term stability in aqueous systems.

The compound is highly soluble in water and forms stable, nearly odorless solutions. It features low irritation potential compared to traditional oxidizing biocides, making it suitable for skin-contact personal care products. It also exhibits residual antimicrobial effect and low tendency to induce microbial resistance.

PHMB Chemical & Physical Properties

Applications of PHMB

Water treatment biocontrol: Used as a non-oxidizing microbial control agent in cooling towers, swimming pools, spa systems and industrial circulating water. It inhibits bacteria, algae and biofilm buildup, maintaining heat transfer efficiency and reducing microbially influenced corrosion.

Personal care preservatives: Incorporated into hand washes, wet wipes, deodorants and contact lens solutions as a mild antimicrobial active. It provides broad-spectrum germ protection with low skin irritation, suitable for daily-use personal care formulations.

Textile antimicrobial finishing: Imparts durable antibacterial and antifungal properties to fabrics, towels, underwear and nonwoven materials. It inhibits odor-causing bacteria and mildew growth, maintaining hygiene and extending fabric service life.

Industrial and institutional disinfection: Applied in surface disinfectants, food processing sanitation and hospital environmental disinfection. It delivers long-lasting residual protection and remains effective under organic load and varying pH conditions.

Storage & Safety Precautions for PHMB

• Store in tightly sealed containers in a cool, dry, well-ventilated warehouse below 30 °C. Keep separated from strong oxidizing agents and highly alkaline materials to avoid activity degradation.
• Wear safety goggles and chemical-resistant gloves during bulk handling. Avoid direct eye contact and prolonged skin exposure. Rinse thoroughly with clean water in case of contact.
• Liquid grades are non-flammable. Reseal opened containers promptly to prevent dilution and microbial contamination, which would reduce biocidal efficacy over time.

PHMB FAQ

Q: How does Poly(hexamethylenebiguanide) hydrochloride (PHMB) work as a biocide?

A: Its cationic biguanide groups adsorb onto negatively charged microbial cell membranes, disrupting membrane structure and permeability to cause intracellular substance leakage. It also inhibits key cellular enzymes and blocks microbial reproduction, delivering broad-spectrum activity against bacteria, fungi and algae with low dosage requirements.

Q: What are the main application areas of PHMB?

A: It is widely used in water treatment for biocontrol, personal care products as a mild preservative, textile antimicrobial finishing, and industrial surface disinfection. Its low irritation profile also makes it suitable for skin-contact daily chemical and hygiene products.

Q: How should PHMB be stored to maintain its antimicrobial activity?

A: Store in tightly sealed containers in a cool, dry place below 30 °C, away from strong oxidizers and high alkalinity. Reseal opened containers promptly to prevent dilution and contamination, which would reduce biocidal efficacy and shorten shelf life.