MSDS for 2,4,6-Trimethylbenzoyl-diphenylphosphine oxide

Identification

Product Name: 2,4,6-Trimethylbenzoyl-diphenylphosphine oxide
Chemical Formula: C22H21O2P
Trade Name: TPO
Manufacturer: Listed on product label
Recommended Use: Photoinitiator in UV-curable formulations
Contact Number for Emergency: Displayed on safety documentation and product packaging
Synonyms: Ethylhexyl dimethylaminobenzoate
CAS Number: 75980-60-8
Relevant Identified Uses: Often found in printing inks, coatings, adhesives, and composite materials processed through UV technology.

Hazard Identification

Classification: Classified as hazardous under regulation (EC) No. 1272/2008, Skin Sensitizer Category 1, Eye Irritant Category 2, Specific Target Organ Toxicity (Single Exposure)
Label Elements: Pictograms of exclamation mark, hazard statements such as H317 (May cause allergic skin reaction), H319 (Causes serious eye irritation), and risk phrases specific to regulatory requirements
Signal Word: Warning
Hazard Statements: Sensitizes skin, can cause irritation to eyes and respiratory tract, possible environmental hazard for aquatic life
Precautionary Statements: Always avoid breathing dust, use protective gloves, wash skin thoroughly after handling, keep product away from drains or water supplies
Symptoms of Exposure: Redness on skin, eye discomfort, sneezing, throat irritation.

Composition / Information on Ingredients

Chemical Identity: 2,4,6-Trimethylbenzoyl-diphenylphosphine oxide
Common Name: TPO
CAS Number: 75980-60-8
EC Number: 278-355-8
Concentration: Typically offered in technical grade at 98-100% concentration
Impurities: Minor trace impurities may stem from manufacturing batch variability, no identified substances subject to separate reporting at levels regulated by current GHS guidelines.

First Aid Measures

Inhalation: Move affected person to fresh air, keep at rest in a comfortable position, get medical help if symptoms develop; remove source of exposure
Skin Contact: Wash with soap and water, remove contaminated clothing, consult a doctor if irritation persists
Eye Contact: Flush with plenty of running water for at least 15 minutes, lift upper and lower eyelids occasionally, seek medical attention if discomfort remains
Ingestion: Rinse mouth with water, do not induce vomiting, seek immediate medical advice
Most Important Symptoms/Effects: Delayed or immediate skin rash, redness, watery eyes, transient respiratory issues
General Advice: In all events, show physician product container or label; persons assisting should avoid direct contact with contaminated clothing or skin.

Fire-Fighting Measures

Suitable Extinguishing Media: Dry chemical powder, foam, carbon dioxide, water spray for large fires (cool tanks with water mist if exposed to fire)
Hazardous Combustion Products: Fumes containing phosphorus oxides, carbon monoxide, carbon dioxide, and aromatic compounds
Unsuitable Extinguishing Media: Direct jet of water may spread burning material
Protective Equipment for Firefighters: Wear self-contained breathing apparatus, full protective gear to avoid skin and eye exposure
Special Firefighting Procedures: Keep people away from hazard area, approach upwind, always use proper containment to prevent environmental contamination.

Accidental Release Measures

Personal Precautions: Avoid contact with skin, eyes, and clothing; do not inhale dust, use disposable gloves and eye shields
Environmental Precautions: Prevent entry into drains, sewers, or waterways; contain spill to smallest area possible with sand or soil
Containment and Cleaning: Scoop up spilled substance into a labeled waste disposal container using non-sparking tools, clean residue with suitable solvent, ventilate area
Reference to Other Sections: Refer to sections on disposal, exposure controls for full procedural guidance.

Handling and Storage

Precautions for Safe Handling: Handle in a closed system or use local exhaust, avoid breathing dust, prevent direct skin and eye contact
Advice on General Occupational Hygiene: No eating, drinking, or smoking in work area; wash thoroughly after handling, remove contaminated clothing
Storage Conditions: Keep container tightly closed in a cool, dry place away from direct sunlight and moisture, store in a locations with adequate ventilation, segregate from strong oxidizing agents, acids, and alkalis
Incompatible Materials: Avoid strong bases, oxidizing substances, and agents that may react exothermically with organic phosphorus compounds.

Exposure Controls and Personal Protection

Occupational Exposure Limits: No established exposure limits for this substance under OSHA, ACGIH, or NIOSH at review, follow workplace threshold guidance for similar dusts
Engineering Controls: Local exhaust ventilation, process enclosure, general room ventilation; use fume extraction at source where fine powder is handled
Personal Protective Equipment: Chemical-resistant gloves (nitrile recommended), safety goggles, laboratory coat or apron, respiratory protection (P2 or N95 mask) if dust exceeds threshold in air
Environmental Controls: Use closed transfer systems where possible, recovery and recycling of waste streams, observe best practices for substance containment.

Physical and Chemical Properties

Appearance: White to off-white crystalline powder
Odor: Slight aromatic or mild organic odor, not highly volatile
Melting Point/Freezing Point: 90 – 104°C range
Boiling Point: Not easily determined due to decomposition at elevated temperatures
Solubility: Insoluble in water, soluble in common organic solvents like acetone, methanol, and ethyl acetate
Vapor Pressure: Very low under standard conditions
Density: Approximately 1.2 g/cm³ at 25°C
Partition Coefficient (log Kow): Data points to moderate mobility within organic environments
Auto-Ignition Temperature: Above 400°C
Decomposition Temperature: Decomposes above 200°C, yielding fumes of phosphorus oxides and aromatic fragments.

Stability and Reactivity

Chemical Stability: Stable in original packaging under recommended storage
Possibility of Hazardous Reactions: Unlikely under normal handling and storage, avoid strong oxidizers or mixing with acids
Conditions to Avoid: Prolonged exposure to high temperatures, UV light, contact with incompatible materials, exposure to flame
Incompatible Materials: Strong acids, alkalines, oxidizing agents, peroxides
Hazardous Decomposition Products: Phosphorus oxides, aromatic carbon oxides, benzene, carbon monoxide if involved in a fire.

Toxicological Information

Acute Toxicity: Oral LD50 (rat) reported at approximately 5000 mg/kg, relatively low acute oral toxicity, but not considered non-toxic
Skin Corrosion/Irritation: Causes transient skin irritation on contact in some individuals, classified as a mild irritant
Serious Eye Damage/Irritation: Causes redness, stinging or watering of the eyes on direct exposure
Skin Sensitization: Known to provoke allergic contact dermatitis in susceptible persons
Respiratory Sensitization: No confirmed data for respiratory sensitization on brief exposure, dust inhalation may irritate upper respiratory tract
Chronic Effects: No evidence of carcinogenicity or mutagenicity observed in standard animal studies; not expected to be a reproductive toxin at typical exposure levels
Target Organs: Primarily skin and eyes through direct exposure.

Ecological Information

Ecotoxicity: Approximately moderate aquatic toxicity, EC50 in Daphnia magna ranges between 1-10 mg/L, strong hazard for aquatic invertebrates with poor biodegradability
Persistence and Degradability: Not readily biodegradable, slow breakdown in soil or aquatic systems, risks of bioaccumulation in sediment
Bioaccumulative Potential: Predicted log Kow above 3 points to potential for bioaccumulation in aquatic environments
Mobility in Soil: Tends to adsorb to organic material in soil, limiting groundwater migration
Other Adverse Effects: May cause long-term adverse effects in the aquatic environment if released in significant quantities or frequently.

Disposal Considerations

Disposal Methods: Collect unused residue and contaminated packaging in tightly sealed containers, submit to licensed hazardous waste contractor, dont attempt to reuse empty packaging before thorough industrial cleaning
Treatment: Waste should not be discharged to sewer systems, waterways, or open land, use incineration in dedicated facility if possible
Local Legislation: Check for regional, national regulatory requirements or prohibitions on landfill or incineration of organo-phosphorus compounds.

Transport Information

UN Number: Product is not classified as hazardous for transport under ADR, IMDG, IATA or DOT at the quantities or concentrations involved in common use
Proper Shipping Name: Not regulated; refer to local transport legislation for correct shipping class
Packing Group: Not assigned
Transport Hazard Class: Not classified as dangerous goods for land, sea, or air transport at technical grade concentrations
Special Precautions: Exercise care to avoid container damage or spills in transit; carriers should be informed about the nature of the chemical and measures in case of accidental release.

Regulatory Information

Labeling: Complies with GHS, CLP, OSHA Hazard Communication Standard
Notification: Substance listed in EINECS, TSCA, AICS, ENCS, and other major global inventoried lists
SARA Title III: Not subject to reporting under CERCLA, SARA 313 at common concentrations
DSL/NDSL (Canada): Substance present on Canadian DSL
Other Regulations: Follow local, state, and national regulations for chemicals in use and storage; safety data to accompany every workplace activity involving this material.