Vazo radical initiators are substituted azonitrile compounds that thermally decompose to generate two free radicals per molecule. (Nitrogen gas is also generated.) The rate of decomposition is first-order and is unaffected by contaminants such as metal ions. The most important criterion for choosing the correct grade of Vazo™ free radical sources is the temperature at which the reaction is to be run. Vazo radical initiators are generally used within a range of 10 to 30°C (18 to 54°F) above the temperature corresponding to the grade number. This range is a rough guideline only. For instance, Vazo 64 has been used at 125°C (257°F), where the half-life is less than 1 minute.

Vazo free radical sources are used to initiate bulk, solution, and suspension polymerizations. These azo initiators can be used alone, or in combination with other free radical initiators. General benefits versus peroxide alternatives include: Head-to-Tail polymerization with less branching/crosslinking, higher control of molecular weight, lower polydispersity, unaffected by heavy metals, contamination, additives etc, and can polymerize oxidation susceptible compounds and functional groups. For more information about Vazo free radical sources, go to our guide in the Article section.

Vazo 52, known as 2-2'-Azobis(2,4-dimethylvaleronitrile) is a free radical source (FRS) typically used as a polymerization initiator. Vazo 52 has the lowest initiation temperature within the Vazo product line. This product will thermally decompose to generate free radicals and nitrogen gas. Benefits of Vazo 52 include:

  • Ideal for low-temperature polymerization
  • Does not compete in costly sides reactions
  • Low polydispersity; monomer distribution control
  • Unaffected by heavy metals, contamination, additives etc
  • Can polymerize oxidation susceptible compound
Vazo Authorized Distributor

Vazo 64, also known as AIBN (Azobisisobutyronitrile), is a free radical source (FRS) typically used as a polymerization initiator. Vazo 64 is one of the most widely used initiators, which thermally decomposes to generate free radicals and nitrogen gas. More cost-effective than organic peroxides of comparable activity. Its low molecular weight allows it to be one of the most cost effective options, with a higher mole per pound than other initiators. Vazo 64 is mainly used to start acrylic polymerization reactions in industrial settings.  Benefits include:

  • Very Cost Effective
  • Does not compete in costly sides reactions
  • Head-to-Tail polymerization; Low polydispersity
  • Unaffected by heavy metals, contamination, additives etc
  • Can polymerize oxidation susceptible compound
Vazo Authorized Distributor

Vazo 67, also known as AMBN 2,2’-Azodi(2-methylbutyronitrile), is a free radical source (FRS) typically used as a polymerization initiator. Vazo 67 has similar thermal characteristics to Vazo 64, with the advantages of a safer decomposition product and higher solubility in a broader range of organic solvents. Can be used as a drop-in for AIBN initiator and it will decomposes to generate free radicals and nitrogen gas.   Benefits include:

  • Highest solubility in  solvents or monomers
  • Does not compete in costly sides reactions
  • Head-to-Tail polymerization: Low Polydispersity
  • Unaffected by heavy metals, contamination, additives etc
  • Can polymerize oxidation susceptible compound
Vazo Authorized Distributor

Vazo 88, also known as ACHN (1,1’-Azobis(cyanocyclohexane)), is a free radical source (FRS) typically used as a polymerization initiator. Vazo 88 is used principally in higher temperature polymerizations with excellent solubilty in a wide variety of organic solvents. Vazo 88 will thermally decomposes to generate free radicals and nitrogen gas. More cost-effective than organic peroxides of comparable activity. Benefits include:

  • Higher temperature activation
  • Does not compete in costly sides reactions
  • Head-to-Tail polymerization
  • Unaffected by heavy metals, contamination, additives etc
  • Can polymerize oxidation susceptible compound
Vazo Authorized Distributor