Dioctyl Phthalate (DOP)
Dioctyl Phthalate (DOP), also known as di(2-ethylhexyl) phthalate (DEHP), is a widely used plasticizer primarily added to polyvinyl chloride (PVC) and other polymers to enhance flexibility, durability, and workability. It is a clear, colorless, oily liquid with a slight ester odor. Due to its excellent compatibility with many polymers and long-lasting plasticizing effects, DOP is one of the most common phthalate plasticizers used in industries such as construction, automotive, packaging, and medical devices. It also serves as a solvent and dispersant in various chemical processes.
Dioctyl Phthalate (DOP) Uses
Primary UsesÂ
- Plastics & Polymer Industry
- Most commonly used as a plasticizer in PVC to improve flexibility, elasticity, and toughness.
- Enhances the softness and durability of flexible vinyl products such as cables, flooring, wall coverings, and synthetic leather.
- Used in the manufacture of flexible hoses, sheets, films, and molded products.
- Provides long-term stability and resistance to aging and weathering in plastic products.
- Coatings, Adhesives & Sealants
- Acts as a solvent and plasticizer in various coatings, inks, adhesives, and sealants to improve spreadability and film flexibility.
- Enhances impact resistance and adhesion properties in formulated coatings.
- Automotive Industry
- Used in automotive interior components such as dashboards, upholstery, and wiring insulation to provide softness and durability.
- Improves vibration damping and resistance to temperature changes in automotive applications.
- Medical Devices
- Historically used in medical-grade PVC products like tubing, blood bags, and catheters to provide flexibility and resilience (usage now restricted or replaced in many regions due to safety concerns).
- Electrical & Electronics
- Used in insulating cables and wires to provide flexibility and protection against mechanical stress.
- Serves as a dielectric fluid in some electrical components.
Secondary UsesÂ
- Printing Inks
- Used as a solvent and plasticizer in printing inks to improve flow and gloss.
- Textile Processing
- Applied as a softening agent in synthetic textile coatings and treatments.
- Rubber & Elastomers
- Acts as a processing aid and softener in some rubber and elastomer formulations.
- Other Specialty Applications
- Used as a carrier solvent for pesticides and other agrochemicals.
Functions as a dispersant in pigment and dye formulations.
- Basic Identification Attributes
- Chemical Name (IUPAC): Bis(2-ethylhexyl) benzene-1,2-dicarboxylate
- Common/Trade Name: Dioctyl Phthalate (DOP), DEHP
- CAS Number: 117-81-7
- HS Code: 2917.39.00
- Molecular Formula: C24H38O4
- Synonyms:
- Di(2-ethylhexyl) phthalate
- DEHP
- Bis(2-ethylhexyl) phthalate
- Phthalic acid dioctyl ester
- Physical & Chemical Properties
- Physical State: Clear, oily, colorless liquid
- Odor: Mild, characteristic ester odor
- Boiling Point: ~384°C
- Melting Point: −50°C
- Density: ~0.986 g/cm³ at 20°C
- Solubility: Insoluble in water; soluble in organic solvents such as alcohols, ethers, and hydrocarbons
- Stability: Chemically stable under normal conditions; sensitive to strong oxidizers
- Safety & Hazard Attributes
- Hazard Class (GHS): Classified as a hazardous substance; possible reproductive toxicity concerns
- Toxicity: Moderate toxicity; potential endocrine disruptor and reproductive hazard (subject to regulatory restrictions)
- Exposure Limits: Varies by jurisdiction; OSHA PEL ~5 mg/m³ (particulates)
- Flammability: Low flammability; combustible liquid
- Storage & Handling Attributes
- Storage Conditions: Store in a cool, dry, well-ventilated area away from heat and ignition sources
- Container Type: Steel drums or HDPE containers, tightly sealed
- Shelf Life: 3–5 years if stored properly
- Handling Precautions: Avoid skin contact and inhalation of vapors; use appropriate PPE
- Regulatory & Compliance Attributes
- Restricted or banned in some applications due to environmental and health concerns (e.g., in toys and childcare articles by EU REACH and US CPSC)
- Listed on REACH and TSCA inventories
- Complies with various industrial standards for plasticizers but subject to evolving regulatory scrutiny
- Environmental & Health Impact
- Ecotoxicity: Toxic to aquatic life; persistence and bioaccumulation potential reported
- Persistence: Moderately persistent in environment
- Bioaccumulation: Potential for bioaccumulation in aquatic organisms
Carcinogenicity/Mutagenicity: Not classified as carcinogenic; concerns primarily focus on reproductive toxicity
 Safety Handling Precautions
PPE Required:
- Chemical-resistant gloves (nitrile or neoprene)
- Safety goggles or face shield
- Protective clothing (lab coat, apron)
- Use respiratory protection if ventilation is poor
Handling Guidelines:
- Minimize skin contact and inhalation of vapors or mist
- Use in well-ventilated areas or under fume hoods
- Avoid open flames and sources of ignition
Storage Measures:
- Keep container tightly closed
- Store away from heat, sparks, and oxidizing agents
- Avoid contamination with water or incompatible materials
Hygiene Practices:
- Wash hands thoroughly after handling
- Do not eat, drink, or smoke during use
- Remove contaminated clothing promptly
First Aid Measures
- Inhalation: Move affected person to fresh air; seek medical attention if breathing difficulty develops
- Skin Contact: Wash with plenty of soap and water; get medical advice if irritation persists
- Eye Contact: Rinse immediately with plenty of water for 15 minutes; consult a physician if irritation occurs
- Ingestion: Rinse mouth; do not induce vomiting; seek immediate medical attention
Firefighting Measures
- Fire Hazards: Combustible liquid; can burn with a smoky flame
- Extinguishing Media: Foam, dry chemical powder, COâ‚‚, or water spray
- Special Precautions: Firefighters should wear self-contained breathing apparatus (SCBA)
Decomposition Products: Carbon monoxide, carbon dioxide, and phthalate decomposition products