Azobisisobutyronitrile

CAS: 78-67-1

Overview

Azobisisobutyronitrile (CAS 78-67-1 ), commonly known as AIBN, is a free-radical initiator used to drive polymerization reactions across a broad range of industrial polymer production processes.

It decomposes at moderate temperatures to generate nitrogen gas and carbon-centered radicals, triggering chain growth in both bulk and solution polymerization systems.

In plastics and polymer manufacturing, AIBN initiates the production of PVC, polystyrene, polyacrylates, and other vinyl-based polymers where controlled radical generation is critical.

Coating formulators use it to cure acrylic and styrenic resin systems, directly influencing film hardness, adhesion, and cross-link density in the final coating application.

In adhesives and sealants, AIBN supports the synthesis of pressure-sensitive and structural adhesive polymers where consistent initiation efficiency affects batch-to-batch performance.

Printing and packaging applications rely on AIBN-initiated resins for UV-stable inks and barrier coatings applied to flexible substrates for various industrial uses.

AIBN is supplied as a white crystalline powder and is the standard commercial form for industrial use. Technical grade is the predominant specification available for buyers.

Purity levels are typically at 98% or higher. Packaging ranges from small quantities to bulk volumes, with temperature-controlled handling required throughout the supply chain.

Physical Properties

Melting Point	105 °C
Boiling Point	>260 °C
Density	0.68 g/cm³ (soild)
Flash Point	4°C
Appearance	Azobisisobutylonitrile is a white crystalline compound.
Color	Crystals from EtOH
Odor	odorless
Form	Solid
Water Solubility	Insoluble
Vapor Pressure	0.81Pa at 24.85℃
Refractive Index	n20/D1.495
Log P	1.1 at 25℃

Safety & Handling

Danger GHS02 GHS07 GHS06 GHS08 Hazard Statements H242 Heating may cause a fire H301 Toxic if swallowed H302 Harmful if swallowed H332 Harmful if inhaled H336 May cause drowsiness or dizziness H361 Suspected of damaging fertility or the unborn child H370 Causes damage to organs H373 May causes damage to organs through prolonged or repeated exposure H412 Harmful to aquatic life with long lasting effects H302+H332 Harmful if swallowed or if inhaled Precautionary Statements P203 Obtain, consult and follow expert instructions for use. P210 Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking. P234 Keep only in original packaging. P235 Keep cool. P240 Ground and bond container and receiving equipment. P260 Do not breathe dust/fume/gas/mist/vapours/spray. P261 Avoid breathing dust/fume/gas/mist/vapours/spray. P264 Wash … thoroughly after handling. P270 Do not eat, drink or smoke when using this product. P271 Use only outdoors or in a well-ventilated area. P273 Avoid release to the environment. P280 Wear protective gloves/protective clothing/eye protection/face protection. P317 Get emergency medical help. P318 IF exposed or concerned, get medical advice. P319 Get medical advice/attention if you feel unwell. P321 Specific treatment (see … on this label). P330 Rinse mouth. P403 Store in a well-ventilated place. P405 Store locked up. P410 Protect from sunlight. P411 Store at temperatures not exceeding … °C/…°F. P420 Store away from other materials. P501 Dispose of contents/container in accordance with local regulations. P301+P316 Get emergency medical help immediately. P301+P317 Get emergency medical help. P304+P340 IF INHALED: Remove person to fresh air and keep comfortable for breathing. P308+P316 Get emergency medical help immediately. P370+P378 Use … for extinction. P403+P233 Store in a well-ventilated place. Keep container tightly closed.

Trade & Regulatory

HS Code	29269090
UN Number	3234
ADR Class	4.1
Storage Class	3 - Flammable liquids
WGK (Germany)	2

Other Names

Industries

Printing & Packaging Coatings, Adhesives, Sealants & Elastomers Plastics & Polymers