Pulse radiolysis studies of styrene

Abstract

Abstract We have applied the pulse radiolysis technique of studying short‐lived, radiation‐produced intermediates to a study of pure, dry liquid styrene. We have observed at least three distinct species. The most rapidly decaying species (τ1/2 = 4 μsec., λ max ≈ 370 mμ) exhibits an apparent first‐order decay which is slowed down in the presence of dry oxygen, occurs too rapidly to be measured in the presence of water, and has a temperature coefficient of approximately 1 kcal./mole between 25 and 45°C. We have tentatively identified the species as the styryl anion with a G value for formation of approximately 0.15. A second species (τ1/2 = 220 μsec. λ max ≈ 320–330 mμ) exhibits a first‐order decay which appears to be independent of oxygen and water. From its spectrum, we have tentatively identified it as the styryl radical. The third species (λ max ≈ 310 and 320 mμ) is relatively stable in the dark, but is radily photolyzed by the analyzing light of the usual experimental set‐up for pulse radiolysis studies. The formation of this species appears to be independent of the water and oxygen content of the styrene.