V-40 is an oil-soluble azo initiator having a high decomposition temperature. It is freely soluble in various organic solvents and has a 10 hour half-life decomposition temperature of 88° C.

Chemical Name


CAS No.: 2094-98-6
Molecular weight: 244.34

Physical characteristics

Appearance White crystals
Melting/freezing point 110-120° C
10 hour half-time decomposition temperature 88° C in toluene
Activation energy 154.1 KJ/mol K
Frequency factor (ln A) 40.5
Solubility Freely soluble in acetone, chloroform and benzene
Soluble in ethanol
Insoluble in water and petroleum ether
Self-accelerating decomposition temperature (SADT) 80° C

Main Applications

  • ABS and PMMA
  • Casted plate and resists


  • EINECS No.: 218-254-8
  • REACH: n/a


Store under 20°C in cool, dry and well-ventilated conditions.

Safety information

Health Hazard
Hazardous to the Environment

For specific information on the safe handling of the product, please refer to the material safety data sheet (MSDS) which is available on request.