快速电子辐照F-40残存自由基热衰减的ESR研究

ESR STUDY ON THERMAL DECAY OF RADICALS TRAPPED IN HIGH-SPEED ELECTRON IRRADIATED F-40

空气中辐照F 40样品中残存的链侧过氧自由基没有链端过氧自由基稳定 .这些自由基的热衰减呈明显二级反应特征 .反应表观活化能与指前因子这两个对反应速率常数起着相反影响的动力学参数之间存在着动力学补偿效应 ,表明自由基热衰减是同时在不同活性中心上进行的复杂反应 .

The mid-chain peroxyl radicals trapped in the samples irradiated in air are les s stable than the end-chain peroxyl radicals. It was indicated that thermal dec ays of the trapped radicals are second-order reactions. The compensation effect s in kinetics exist between the apparent activation energy and the pre-exponent factor which effect reaction rate constants contrarily. Such phenomenon indicat es that thermal decays of the trapped radicals are complex reactions which occur simultaneously at many active centres. \;