Basic Information：

Chinese Name: 四氢呋喃

English Name:Tetrahydrofuran

Abbreviation: THF

CAS No.: 109-99-9

UN No.: 2056

Molecular Formula:C₄H₈O

Molecular Weight: 72.11 g/mol

Appearance and Properties: Colorless, clear and volatile liquid with an ether-like odor

Boiling Point: 66 °C (151 °F)

Melting Point: -108.4 °C (-163.1 °F)

Density: 0.8892 g/cm³ (at 20 °C)

Flash Point: -14 °C (6.8 °F, closed cup)

Autoignition Temperature: 321 °C (610 °F)

Solubility: Miscible with water, alcohols, ethers, ketones, esters, hydrocarbons and most other organic solvents

Solvent Properties：

Tetrahydrofuran (THF) is a polar aprotic solvent with excellent solubility and good process compatibility, serving as a widely used general solvent in the chemical industry. Its core properties are as follows:

Excellent Compatibility

Miscible with water, alcohols, ethers, ketones, esters, hydrocarbons and most other organic solvents, forming a homogeneous system.

It has superior dissolving power for polymers, capable of dissolving polyvinyl chloride (PVC), polyurethane (PU), polytetramethylene ether glycol (PTMEG), thermoplastic elastomers and other materials, making it an ideal solvent for polymer processing.

Favorable Physical Properties

Low viscosity: With a viscosity of only 0.55 mPa·s at 20 °C, it exhibits good fluidity in processes such as coating, dipping and reaction, improving product uniformity.

Moderate volatility: Boiling at 66 °C, it can be quickly removed during drying and curing procedures, shortening the production cycle without excessive solvent residue.

Stable Chemical Performance

Stable under normal temperature and pressure, and not prone to reactions with most substances.

Prone to ring-opening polymerization under catalysis of strong acids or peroxides, which is the theoretical basis for its application as a monomer in PTMEG synthesis.

Main Applications：

THF is a dual-functional chemical that acts as both a solvent and an intermediate, with applications spanning fine chemicals, materials industry and other fields. Its core uses are as follows:

Polymer Industry (Core Application Field)

PTMEG synthesis monomer: This is the most important application of THF, accounting for over 70% of its total consumption. PTMEG produced by THF polymerization is a key raw material for spandex (Lycra), polyurethane elastomers and polyurethane fibers.

Polymer processing solvent: Used as a solvent for PVC adhesives, PU coatings and thermoplastic rubbers, it enhances product adhesion and film-forming properties.

Organic Synthesis Field

Serves as a dedicated solvent for Grignard reactions, lithium aluminum hydride reduction reactions and organolithium reactions, suitable for anhydrous and oxygen-free reaction systems, significantly improving reaction yield and selectivity.

Acts as an intermediate in the synthesis of pharmaceuticals, pesticides and fine chemicals, used to produce antibiotics, herbicides, special surfactants and other products.

Other Application Scenarios

Solvent extraction: Applied in the separation and purification of aromatic hydrocarbons and heavy metal ions, featuring high extraction efficiency and good separation effect.

Coating and printing industry: Used as a component of paint thinners and ink solvents, improving the leveling property of coatings and the drying speed of inks.

Safety：

Hazard Classification

Flammable liquids (Category 2): Closed-cup flash point as low as -14 °C, prone to forming explosive mixtures with air.

Skin irritants (Category 2): Contact may cause erythema, itching, dermatitis and other symptoms.

Eye irritants (Category 2A): Can lead to eye discomfort, tearing and conjunctival congestion.

Suspected reproductive toxicants (Category 2): Long-term exposure may have adverse effects on reproductive function.

Operational Safety Precautions

Fire and Explosion Prevention：

Store in a cool, well-ventilated and fire-resistant warehouse with storage temperature not exceeding 30 °C, away from ignition sources and heat sources.

Avoid contact with strong oxidants (e.g., hydrogen peroxide, potassium permanganate), strong acids (e.g., concentrated sulfuric acid) and reducing agents to prevent violent reactions.

Use explosion-proof electrical equipment and tools in the workplace; strictly prohibit smoking and open flames.

Personal Protection：

Wear nitrile rubber gloves, chemical safety goggles and anti-static work clothes during operation to avoid direct contact with skin and eyes.

Operate in a well-ventilated fume hood; wear a half-mask respirator equipped with organic vapor cartridges when vapor concentration exceeds the limit.

Thoroughly wash hands and face with soap and water after operation; do not eat, drink or smoke in the work area.

Emergency Treatment Measures

Leakage Handling：

Immediately cut off ignition sources, evacuate personnel to the upwind direction and set up a warning zone.

Do not flush the leaked material with water; use inert absorbents such as sand and activated carbon to absorb the leakage, transfer the absorbed waste to a sealed container and entrust it to professional institutions for disposal.

Fire Fighting Measures：

Use carbon dioxide, dry powder or foam fire extinguishers to put out fires; never use water directly to extinguish the fire, as water may cause liquid splashing and expand the fire range.

Firefighters must wear full-body fire and chemical protective suits and operate from the upwind direction.

Accidental Contact Treatment

Skin contact: Immediately rinse the contaminated area with plenty of running water for at least 15 minutes; seek medical attention promptly if irritation persists.

Eye contact: Immediately lift the eyelids and rinse with flowing normal saline or clean water for 15–20 minutes, then seek medical attention without delay.

Ingestion: Do not induce vomiting; drink a small amount of warm water to dilute stomach contents and seek medical treatment immediately.

Storage and Transportation Requirements

Packaging: Pack in sealed metal drums or high-density polyethylene (HDPE) containers, and affix standard flammable liquid hazard labels on the packages.

Transportation: Strictly comply with national regulations on the transportation of dangerous goods; avoid mixed transportation with oxidants, acids and edible chemicals; prevent exposure to sunlight, rain and collision during transportation.