丙炔醇环四聚体的辐射化学研究

STUDIES OF THE RADIATION CHEMISTRY OF 2,5-DIMETHYL-2,5-BIS (2-PROPYNYLOXY)-1,4 DIOXANE

用γ-射线对丙炔醇环四聚体的晶体进行照射,无色透明的晶体逐渐变为棕色;利用红外光λ和核磁共振等方法研究了晶体的变化;ESR证实辐照产生了大量的自由基,测得自由基的g值是2.0048,自旋浓度为10^(17)～10^(17)spins/g;对晶体进行加热处理表明该自由基在低于110℃时相当稳定,很少复合,但可发生自由基反应而生成更稳定的自由基;探讨了自由基的碎裂、复合生成聚合产物以及通过链反应生成高聚物的机理。

The effects of γ-ray on thc crystalline title compound have been studied, the colorless transparent crystal turned brown and produced some gases accompanied by the decrease in melting point, the value of decrease was in proportion to the radiation dose. IR and NMR pectra indicated that no significant amounts of polymer were obtained. It is determined by ESR that there are a lot of free radicals in the radiated samples the g value is 2.0048 and the yield G is 2.5. These radicals, are quite stable below 110℃, at 110℃ for 3 hours, the ESR spectra splited into several peaksdue to the recombination of rabicats; after being heated at 120℃ for one hour, the ESR signals disappeared, and some carbonyl compounds were gained.