Azo polymerization initiators


CAS : 27776-21-2

non-nitrile low-temperature type water soluble

Plastics manufacturing


VA-044 is a non-nitrile, cationic water-soluble azo polymerization initiator. It is highly effective for the polymerization of water-soluble vinyl monomer. The 10-hour half-life temperature is as low as 44 ºC, and the product is active at low temperatures.

  • Non-nitrile water-soluble azo initiator having low decomposition temperature
  • Soluble in water or methanol
  • 10 Hour half-life decomposition temperature: 44℃(in water)
structural formula of 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride
Chemical name 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride
CAS RN® 27776-21-2
Molecular weight 323.27
Molecular formula C12H22N6·2HCl
Synonyms AIPC

Physical characteristics

pale yellow
crystals or crystalline powder
Melting point/freezing point 188-193(dec.) °C
10hour half-life decomposition temperature 44℃(in water)
Activation energy 108.2 kJ/mol
Frequency factor (ln A)


Solubilities water : freely soluble.
methanol : sparingly soluble.
ethanol : very slightly soluble.
acetone, toluene : insoluble.
SADT 140℃

*SADT: Self-accelerating decomposition temperature

Packaging & Storage conditions

Packaging 20kg / 500g
Storage conditions keep under 40℃

Related laws and regulations

TSCA Listed
REACH 01-2120764032-64-0000

Here, you can calculate the ‘residue rate’, ‘decomposition reaction time’, and ‘temperature during the decomposition reaction’ of azo polymerization initiators.

Image of Azo Residue Rate Calculation Tool