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Product Name: Tetrahydrophthalic Anhydride
Synonyms: 1,2,3,6-Tetrahydrophthalic anhydride; Cyclohex-4-ene-1,2-dicarboxylic anhydride
CAS Number: 935-79-5
Recommended Use: Intermediate for resins, plasticizers, curing agents
Supplier Details: Manufacturer or local distributor, including address and emergency phone
Emergency Contact: National poison helpline or company emergency number
REACH Registration No.: If applicable, shall be provided by supplier
GHS Classification: Skin Irritation (Category 2), Eye Irritation (Category 2), Respiratory Sensitization (Category 1), Skin Sensitization (Category 1), Acute Toxicity Oral (Category 4)
Label Elements: Pictograms showing exclamation mark, health hazard symbol
Signal Word: Danger
Hazard Statements: Causes skin irritation, causes serious eye irritation, may cause allergic or asthmatic symptoms or breathing difficulties if inhaled, harmful if swallowed, may cause an allergic skin reaction
Precautionary Statements: Wear protective equipment, avoid skin and eye contact, do not breathe dust or vapors, use only outdoors or in well-ventilated spaces
Chemical Name: Tetrahydrophthalic Anhydride
Chemical Formula: C8H8O3
Content: ≥99%
Impurities: Maleic Anhydride, typically ＞0.05%
Other Ingredients: No significant inactive ingredients
CAS Numbers: Tetrahydrophthalic Anhydride: 935-79-5; Maleic Anhydride: 108-31-6
Inhalation: Remove to fresh air, keep person resting, seek medical attention for persistent symptoms, provide oxygen if breathing difficulties develop
Skin Contact: Remove contaminated clothing, wash skin with large volumes of water and mild soap, do not reuse contaminated clothing until cleaned
Eye Contact: Hold eyelids apart and flush eyes with running water for no less than 15 minutes, remove contact lenses if present, seek immediate medical evaluation
Ingestion: Rinse mouth with water only if victim conscious, avoid inducing vomiting, seek medical care promptly
Note for Physicians: Treat symptomatically, observe for delayed reactions involving respiratory tract or skin
Suitable Extinguishing Media: Dry chemical powder, alcohol-resistant foam, carbon dioxide, water spray for large fires
Specific Hazards: Will decompose on combustion producing toxic fumes including carbon monoxide, carbon dioxide, and maleic anhydride vapors
Protective Equipment for Firefighters: Full protective suit and self-contained breathing apparatus
Firefighting Procedures: Move containers away from fire zone if safe, stay upwind, prevent run-off from entering drains, cool containers with water spray if exposed to flames
Explosion Hazards: Fine dust in air may form explosive mixtures with air under certain conditions
Personal Precautions: Wear gloves, goggles, protective clothing, and respirator for dust
Environmental Precautions: Prevent spillage from entering soil, surface water or drains, report large spills to local environmental authority
Spill Cleanup Methods: Collect spilled solid with non-sparking tools into sealable containers, avoid dust generation, ventilate area, dispose as hazardous waste according to local regulation
Decontamination: Wash contaminated areas with water and detergent, ventilate to clear vapors or dust
Emergency Procedures: Evacuate unnecessary personnel, restrict access to area
Handling: Use only in well-ventilated locations, avoid inhalation of dust or vapors, avoid skin and eye contact, do not eat or drink in work area, keep away from acids, oxidizing agents, and food
Technical Measures: Employ local exhaust ventilation, control dust formation, use anti-static tools
Storage Conditions: Keep containers tightly closed in a dry, cool, and well-ventilated place, store separately from incompatible materials, avoid moisture
Packaging Materials: Use original packaging or containers resistant to corrosive materials, label containers clearly
Special Rules: Do not store near strong oxidizers or bases, check for regular signs of leakage or container damage
Engineering Controls: Employ ventilation systems, provide eyewash and safety shower stations, minimize dust formation with enclosures
Personal Protection: Protective gloves (nitrile or neoprene), chemical safety goggles, long-sleeved clothing, dust mask or respirator (N95 or better for particulates, organic vapor mask for fumes)
Exposure Limits: Maleic anhydride: ACGIH TLV 0.01 ppm (sensitizer), no established limit for tetrahydrophthalic anhydride, monitor workplace air as applicable
Hygiene Measures: Wash hands after handling, remove contaminated clothing immediately, do not eat or drink during use
Respiratory Protection: Use approved respirators if exposure risk exists, especially in poorly ventilated areas or during spill cleanup
Appearance: White to pale yellow crystalline solid
Odor: Slight pungent, acrid odor
Odor Threshold: Not available
Molecular Weight: 152.15 g/mol
Melting Point: 98 - 105°C
Boiling Point: Decomposes before boiling
Decomposition Temperature: Above 210°C
Solubility: Slightly soluble in water, soluble in alcohols, acetone, and ether
Vapor Pressure: Negligible at room temperature
Density: 1.388 g/cm³ (at 25°C)
Flash Point: 192°C (closed cup)
Evaporation Rate: Not applicable
Explosive Properties: Not classified as explosive, but dust can deflagrate
Auto-Ignition Temperature: Around 380°C
Chemical Stability: Stable under normal storage and handling conditions, sensitive to moisture
Reactivity: Reacts with strong bases, amines, and oxidizing agents, generates heat and corrosive products in contact with water or alkali
Hazardous Decomposition Products: Carbon oxides, maleic anhydride fumes, phthalic compounds upon burning
Conditions to Avoid: Heating above decomposition point, exposure to flame, strong acids or bases, moisture
Polymerization: Not known to polymerize under normal conditions but reacts exothermically with nucleophiles
Acute Toxicity: Harmful if inhaled, swallowed, or absorbed through skin, estimated LD50 (oral, rat) ~ 1,000 mg/kg
Skin Irritation: Causes persistent or recurrent dermatitis for sensitive individuals
Eye Effects: Causes moderate to severe irritation, reversible damage possible
Sensitization: High risk for allergy in sensitive people, particularly respiratory and dermal sensitization
Chronic Effects: Long-term exposure may affect respiratory and skin function, possible increased risk for asthma or chronic eczema where exposure is not controlled
Carcinogenicity / Mutagenicity / Reproductive Toxicity: No established evidence for carcinogenic or reproductive issues in humans, but studies on related compounds recommend strong control of exposure
Ecotoxicity: Toxic to aquatic life, especially invertebrates, may lead to oxygen depletion in water systems
Aquatic Toxicity: LC50 (fish, 96h) ~ 30-60 mg/L
Persistence and Degradability: Degrades slowly in soil, hydrolyzes to corresponding acid in contact with water, not persistent in surface waters
Bioaccumulation Potential: Not expected to bioaccumulate due to low octanol-water partition coefficient and rapid metabolism in organisms
Mobility in Soil: Moderately mobile, leaches in moist conditions, contaminates groundwater in large releases
Other Adverse Effects: Can acidify water, disrupt aquatic ecosystems at moderate concentrations
Disposal Methods: Collect dry waste in sealed, labelled containers for hazardous incineration by licensed contractor
Unused Product: Recommended high-temperature incineration, do not dispose of in normal sewage or refuse streams
Contaminated Packaging: Rinse containers with suitable solvent, render unusable before landfilling as hazardous industrial waste
Regulatory Requirements: Comply with local, regional, and national waste regulations for hazardous chemicals
UN Number: 3261 (for corrosive solid, acidic, organic, n.o.s.)
Proper Shipping Name: Corrosive solid, acidic, organic, n.o.s. (contains Tetrahydrophthalic Anhydride, Maleic Anhydride)
Transport Hazard Class: 8 (corrosive)
Packing Group: III
Label Requirements: Corrosive symbol, proper UN number
Special Precautions for Transport: Secure all packages, protect from physical damage and moisture, provide emergency access to MSDS during transport, do not transport with foodstuffs or incompatible chemicals
Global Inventory Status: Listed on relevant inventories such as TSCA (US), EINECS/ELINCS (EU), ENCS (Japan), AICS (Australia), DSL (Canada)
Workplace Regulations: Subject to OSHA Hazard Communication Standard, EU CLP Regulation, GHS requirements for hazard communication
Additional National/Regional Controls: Report as required under EPA SARA Title III, CERCLA for maleic anhydride content
Labeling Requirements: Comply with GHS labeling, include hazard pictograms, signal word, and hazard/precaution statements
Restriction on Use: Not for retail sale to general public, permitted for use only by trained professionals
Third-party Certification or Risk Assessment: Recommended engagement with approved industrial hygiene or chemical safety consultants for workplace monitoring and staff training
