ARADUR 21

ARADUR 21 is a low-viscosity aliphatic amine curing agent formulated for use in liquid epoxy resin systems, particularly those designed for ambient-temperature curing.
ARADUR 21 is a hardener and corrosion inhibitor based on trimethyl hexamethylene diamine (TMD).
ARADUR 21 is also exhibits good resistance to aliphatic and aromatic hydrocarbons, good mechanical properties and optimal cure effects.

CAS Number: 25513-64-8

Synonyms: ARADUR, Hardener, Curing Agent, Epoxy Hardener, Amine Curing Agent, Resin Hardener, Modified Aliphatic Amine, Epoxy Curing Component, Liquid Hardener, Amine-Based Hardener

ARADUR 21 is a low-viscosity aliphatic amine curing agent formulated for use in liquid epoxy resin systems, particularly those designed for ambient-temperature curing.
As a reactive hardener, ARADUR 21 contains active hydrogen groups that chemically react with the epoxide rings of epoxy resins through a polyaddition mechanism.
This reaction leads to the formation of a highly crosslinked three-dimensional thermoset network, which provides mechanical strength, chemical resistance, and durable adhesion to various substrates.

Compared to aromatic amine hardeners, ARADUR 21 offers improved color stability and reduced yellowing, making it suitable for applications where appearance and long-term aesthetic performance are important.
ARADUR 21 is commonly used in industrial floor coatings, protective maintenance coatings, structural adhesives, repair mortars, and casting compounds.

ARADUR 21's balanced reactivity allows effective curing at room temperature while maintaining workable pot life and manageable processing characteristics.
The cured systems typically exhibit good hardness, strong substrate adhesion, resistance to chemicals and moisture, and reliable performance in demanding construction and industrial environments.

ARADUR 21 is valued for its balanced reactivity, good adhesion to various substrates, and ability to produce cured systems with enhanced durability and resistance to chemicals and moisture.

ARADUR 21 is a low-viscosity aliphatic polyamine.
ARADUR 21 is a hardener and corrosion inhibitor based on trimethyl hexamethylene diamine (TMD).

ARADUR 21 exhibits low-viscosity, good resistance to aliphatic and aromatic hydrocarbons, very good mechanical properties following optimal cure, good color stability, good resistance to aqueous neutral and alkaline solutions.
ARADUR 21 is used in solvent-free coatings and flooring.

ARADUR 21 is an aliphatic polyamine.
ARADUR 21 acts as a curing agent.

ARADUR 21 exhibits good color stability, low viscosity, good resistance to aqueous, neutral and alkaline solutions.
ARADUR 21 is also exhibits good resistance to aliphatic and aromatic hydrocarbons, good mechanical properties and optimal cure effects.

ARADUR 21 is a liquid aliphatic amine curing agent developed by Huntsman Corporation for use with epoxy resins.
ARADUR 21 is primarily designed to cure liquid epoxy systems at room temperature, forming highly crosslinked thermoset polymers.

Due to its amine functionality, ARADUR 21 reacts with epoxy groups through a polyaddition mechanism, resulting in coatings and adhesive systems with good mechanical strength, chemical resistance, and adhesion.
ARADUR 21 is commonly used in industrial flooring, protective coatings, adhesives, and construction-related epoxy formulations.

Uses of ARADUR 21:
ARADUR 21 is used as a curing agent for liquid epoxy resins in ambient-temperature systems.
ARADUR 21 is widely applied in industrial floor coatings, protective maintenance coatings, and concrete repair systems where strong adhesion and chemical resistance are required.

ARADUR 21 is also used in structural adhesives, epoxy mortars, casting and grouting compounds, and construction bonding systems.
Additionally, ARADUR 21 is suitable for coatings and resin systems used in civil engineering, infrastructure, and general industrial applications that demand durable, mechanically resistant thermoset materials.

Advantages of ARADUR 21:
ARADUR 21 provides efficient ambient-temperature curing, allowing epoxy systems to harden without external heat.
ARADUR 21 offers balanced reactivity, ensuring a practical working time while achieving reliable crosslinking.

ARADUR 21 delivers strong adhesion to concrete, metal, and mineral substrates.
ARADUR 21 improves chemical resistance against oils, fuels, and industrial chemicals.

ARADUR 21 enhances mechanical properties such as hardness, tensile strength, and abrasion resistance.
ARADUR 21 provides good color stability compared to aromatic amine hardeners.
ARADUR 21 supports durable performance in flooring, coatings, and construction applications.

Stability and Reactivity of ARADUR 21:

Chemical stability:
Stable under recommended storage conditions.

Reactivity:
Reacts exothermically with epoxy resins.
Reacts with acids and strong oxidizers.

Conditions to avoid:
Heat, direct sunlight, moisture contamination, and contact with incompatible materials.

Incompatible materials:
Strong acids, strong oxidizing agents, epoxides (uncontrolled reaction risk), acid chlorides.

Hazardous decomposition products:
Carbon oxides (CO, CO₂), nitrogen oxides (NOx), and irritating amine fumes in fire.

Handling and Storage of ARADUR 21:

Handling:
Avoid skin and eye contact.
Avoid breathing vapors or mists.
Use adequate ventilation.
Do not mix with epoxy in large masses without temperature control.

Storage:
Store tightly closed in a cool, dry, well-ventilated area.

Storage conditions:
Protect from moisture, heat sources, and direct sunlight.
Keep away from acids and oxidizers.

First Aid Measures of ARADUR 21:

Inhalation:
Move to fresh air.
Seek medical attention if symptoms persist.

Skin contact:
Remove contaminated clothing.
Wash thoroughly with soap and water.
Seek medical advice if irritation or burns occur.

Eye contact:
Rinse cautiously with water for at least 15 minutes.
Seek immediate medical attention.

Ingestion:
Rinse mouth.
Do not induce vomiting.
Seek immediate medical attention.

Most important symptoms:
Corrosive or irritating effects.
Eye damage risk.
Skin irritation or burns.
Respiratory irritation.

Firefighting Measures of ARADUR 21:

Suitable extinguishing media:
Foam, dry chemical powder, carbon dioxide, or water spray.

Specific hazards:
Combustible.
Releases irritating or toxic amine fumes when burning.

Protective equipment for firefighters:
Self-contained breathing apparatus and full protective gear.

Special precautions:
Cool containers with water spray.
Prevent firefighting runoff from entering drains or waterways.

Accidental Release Measures of ARADUR 21:

Personal precautions:
Avoid contact and inhalation.
Ensure ventilation.
Wear personal protective equipment including gloves, goggles or face shield, and protective clothing.

Environmental precautions:
Prevent entry into drains, soil, and waterways.

Methods for cleanup:
Contain spill with inert absorbent such as sand or vermiculite.
Collect in suitable containers.
Wash residue carefully.
Dispose according to regulations.

Exposure Controls / Personal Protection of ARADUR 21:

Occupational exposure limits:
Not specifically established for the mixture.
Control vapor or mist exposure.

Engineering controls:
Local exhaust ventilation recommended.

Respiratory protection:
Use appropriate respirator if ventilation is insufficient or aerosol forms.

Hand protection:
Chemical-resistant gloves such as nitrile, butyl, or neoprene.

Eye protection:
Chemical goggles and face shield recommended.

Skin protection:
Protective clothing.
Avoid repeated exposure.

Hygiene measures:
Wash hands after handling.
Remove contaminated clothing.
Do not eat, drink, or smoke in work area.

Identifiers of ARADUR 21:
CAS Number: 25513-64-8
Trade Name: ARADUR 21
Manufacturer: Huntsman Corporation
Chemical Type: Aliphatic amine curing agent
Physical State: Liquid
Appearance: Clear to slightly yellow liquid

Properties of ARADUR 21:
Physical state: Liquid
Appearance: Clear to pale yellow
Odor: Amine-like characteristic odor
Density (25 °C): Approx. 0.95–1.05 g/cm³
Viscosity (25 °C): Low to medium viscosity

Solubility: Miscible with many epoxy resins
Reactivity: Highly reactive toward epoxy groups
Amine value: High
Curing behavior: Room-temperature curing