Material Safety Data Sheet – Di-Benzoyl Peroxide Variants: Enox Bw50 / Enox Bpo-50F / Enox Bpo-75W

Identification

Product Name: Di-Benzoyl Peroxide Enox Bw50, Enox Bpo-50F, Enox Bpo-75W
Chemical Formula: C₁₄H₁₀O₄
Recommended Use: Polymerization initiator, crosslinking agent, vulcanizing agent, curing agent for unsaturated polyester resins, plastics, and rubber.
Supplier: Manufacturer information, contact details, emergency telephone number, and address provided by the supplier.
Synonyms: Dibenzoyl peroxide, benzoyl superoxide.
CAS Number: 94-36-0
EC Number: 202-327-6

Hazard Identification

Classification: Organic peroxide Type B, Eye Irritation Category 2, Skin Sensitization Category 1, Aquatic Acute Category 1, Aquatic Chronic Category 1.
Signal Word: Danger
Hazard Statements: Heating may cause a fire. Causes serious eye irritation. May cause allergic skin reaction. Very toxic to aquatic life with long lasting effects.
Pictogram: Flame, exclamation mark, environment.
Precautionary Statements: Avoid contact with eyes and skin. Keep away from heat, sparks, open flames, and hot surfaces. Use explosion-proof electrical equipment. Wash hands thoroughly after handling. Avoid release to the environment. Wear protective gloves, protective clothing, eye protection, and face protection.

Composition / Information on Ingredients

Chemical Name: Dibenzoyl peroxide
Concentration: Enox Bw50: 50%, Enox Bpo-50F: 50%, Enox Bpo-75W: 75% (by weight), remainder consists of water, phthalate, inert fillers and/or wetting agents.
Hazardous Components: Dibenzoyl peroxide (CAS 94-36-0);
Impurities/Additives: Water and phthalic phthalate for stabilization, fillers as per grade specifications

First Aid Measures

Inhalation: Move person to fresh air. Seek immediate medical attention if problems persist or breathing is difficult.
Skin Contact: Immediately wash with plenty of soap and water for at least 15 minutes. Remove contaminated clothing and shoes. Seek medical advice for any irritation or allergic reaction.
Eye Contact: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing. Seek prompt medical attention.
Ingestion: Rinse mouth. Do not induce vomiting. Seek immediate medical advice and treatment.
Note to Physician: Treat symptomatically, monitor for delayed allergic reactions or respiratory issues.

Fire-Fighting Measures

Extinguishing Media: Use water spray, foam, dry chemical, or carbon dioxide. Never use dry sawdust or similar absorbents.
Specific Hazards: Product decomposes rapidly when heated, releasing oxygen and flammable vapors; risk of explosion if confined.
Advice for Firefighters: Wear full protective gear and self-contained breathing apparatus. Remove containers from fire area if possible without risk. Cool fire-exposed containers with water spray.
Decomposition Products: Carbon dioxide, carbon monoxide, benzoic acid, benzene vapors.

Accidental Release Measures

Personal Precautions: Keep unnecessary personnel away from spill area. Wear suitable personal protective equipment including gloves and eye/face protection. Avoid breathing dust or vapors.
Environmental Precautions: Prevent entry into waterways, drains, or soil. Notify authorities if product enters the environment.
Spill Cleanup Methods: Remove all sources of ignition. Collect and place material in appropriate, clean and dry containers for disposal in accordance with local regulations. Use non-sparking tools.
Decontamination: Ventilate area, wash with copious water after collection.

Handling and Storage

Handling: Keep container tightly closed, away from direct sunlight, heat, sparks, and open flames. Handle in well-ventilated area. Use only non-sparking tools. Avoid any contact with incompatible substances, especially reducing agents or combustibles. Avoid generating dust.
Storage: Store under controlled temperature (below 30°C; recommended 2–8°C for stability), in a dry and well-ventilated place. Use only containers made of compatible materials. Keep separate from strong acids, bases, oxidizers, and combustibles. Prevent build-up of electrostatic charge.
Storage Class: Organic peroxide, regulated environment.

Exposure Controls and Personal Protection

Occupational Exposure Limits: OSHA PEL: 5 mg/m³ (as benzoyl peroxide), ACGIH TLV: 5 mg/m³ TWA
Engineering Controls: Use local exhaust ventilation to keep airborne concentrations below exposure limits. Explosion-proof electrical systems in process areas.
Personal Protection: Wear chemical-resistant gloves, safety goggles, protective clothing, and face protection. In situations with high dust levels, use respiratory protection approved for organic dusts/peroxides.
Hygiene Measures: Avoid eating, drinking, or smoking during handling. Wash thoroughly after handling.

Physical and Chemical Properties

Appearance: White, free-flowing powder or water-wet paste, depending on product variant
Odor: Faint aromatic, benzaldehyde-like
Melting Point: 103–105°C (pure substance)
Water Solubility: Insoluble
Partition Coefficient: log Kow: 3.46
pH (water solution): Neutral to slightly acidic
Flash Point: Not applicable (decomposes before boiling)
Boiling Point: Not applicable
Decomposition Temperature: >50°C (initiates rapid decomposition)
Vapor Pressure: Negligible
Density: Approx 1.3 g/cm³

Stability and Reactivity

Stability: Stable under recommended storage conditions. Sensitivity to heat, friction, shock, and contamination.
Polymerization Hazard: Not expected, but decomposition produces heat and gases rapidly.
Conditions to Avoid: Elevated temperature, exposure to sunlight, contamination with incompatible materials (acids, bases, accelerators, reducing agents), friction, or impact.
Incompatible Materials: Powdered metals, amines, acids, bases, reducing agents, organic solvents, strong oxidizers.
Hazardous Decomposition Products: Carbon dioxide, carbon monoxide, benzoic acid, benzene, phenyl compounds.

Toxicological Information

Acute Toxicity: LD₅₀ (oral, rat): >5,000 mg/kg; LD₅₀ (dermal, rabbit): >2,000 mg/kg
Inhalation: Dust may cause respiratory irritation, coughing, and shortness of breath.
Skin Contact: May cause redness, irritation, or allergic dermatitis in sensitized individuals.
Eye Contact: Causes severe irritation, redness, watering, blurred vision.
Chronic Effects: Repeated or prolonged skin contact may cause sensitization or eczema.
Sensitization: Skin sensitizer
Genotoxicity / Carcinogenicity: Not classified as carcinogenic by IARC, NTP, or OSHA.

Ecological Information

Ecotoxicity: Highly toxic to aquatic organisms. LC₅₀ (Fish, 96hr): <1 mg/L. EC₅₀ (Daphnia magna, 48hr): 0.07 mg/L.
Persistence and Degradability: Readily degradable under environmental conditions.
Bioaccumulative Potential: Low to moderate potential; log Kow indicates some accumulation possible in aquatic organisms.
Mobility in Soil: Low based on water insolubility and molecular structure.
Other Adverse Effects: Large releases may cause oxygen depletion and long-term harm to aquatic ecosystems.

Disposal Considerations

Waste Disposal: Dispose of as hazardous waste in accordance with local, state, and federal regulations. Incineration under controlled conditions recommended. Do not dispose of with normal waste or sewer.
Contaminated Packaging: Empty containers may retain hazardous residues. Dispose as hazardous material.
Handling for Disposal: Wear appropriate protective clothing and equipment. Avoid dust formation and sparks during collection and transport.
Disposal Regulations: Follow specific guidelines for organic peroxide disposal to prevent accidental decomposition or fire.

Transport Information

UN Number: UN3106 (organic peroxide type D, solid, temperature controlled)
Proper Shipping Name: Dibenzoyl peroxide, wet or paste, with not less than 50% peroxide
Hazard Class: 5.2 (Organic Peroxide)
Packing Group: II
Label: Organic Peroxide, Marine Pollutant (if shipped by sea)
Special Provisions: Keep at controlled temperature, away from sources of ignition, do not ship with food or feedstuffs.
Transport in Bulk: Not recommended.

Regulatory Information

Classification and Labeling: OSHA Hazard Communication Standard (29 CFR 1910.1200), EU CLP Regulation (EC) No 1272/2008, GHS
SARA Title III: Listed (immediate [acute] health hazard, reactive hazard)
TSCA: Listed
REACH: Registered substance under ECHA regulations
California Prop 65: Not listed
Other Local Regulations: Addressed by national and regional chemical inventory lists according to product usage and hazard classification.
Workplace Restrictions: Use in accordance with safety guidelines and occupational exposure standards.