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研究了聚氯乙烯在四氢呋喃与环已酮混和溶剂中的辐照效应，发现凝胶量（同一剂量 下）与混和溶剂组份间的关系不符合加和规则而呈现正偏离。相当于分子在电子激发态下的 “敏化保护作用”，上述正偏离现象用正电荷在环已酮正离子与四氢呋喃分子间传递的概念 来解释。 测定了不同含氯量氯化低压聚乙烯辐照后的电子顺磁共振讯号，发现讯号强度确随高分 子中氯基团增加而线性上升。进一步研究在结晶温度下自旋浓度的衰退速度，亦得到类似的 结果。至此，聚氯乙烯辐照时形成负离子的假说就与上述混和溶剂中辐照的由于正电荷传递 而产生正偏离的现象相互统一起来。 我们同时研究了一系列添加物对聚氯乙烯的四氢呋喃或环已酮溶液辐照时的影响，发现 同一添加物在两种溶液中的作用并不一致。三乙胺与乙醚促进了环已酮溶液中的交联作用， 这可能与混和溶剂中的离子“敏化作用”一样。水，乙醇及醋酸则抑止了环已酮溶液中的交 联。这些物质对交联的抑止作用可能与低温辐射离子聚合时的阻聚作用相类似。一系列添加 物在四氢呋喃溶液中影响不大，这可能因为四氢呋喃正离子本身已大大促进交联作用，因此 少量添加物的作用并不明显。 最后，对聚氯乙烯水悬浮液中各种添加物的影响也进行了一定的研究。
The irradiation effect of PVC on the mixed solvents of tetrahydrofuran and cyclohexanone was studied. It was found that the relationship between the amount of gel (under the same dosage) and the components of mixed solvents did not accord with the addition rules and showed a positive deviation. Which is equivalent to the “sensitization protection” of the molecule in the electron excited state. The positive deviation is explained by the concept that the positive charge is transferred between the cyclohexanone positive ion and the tetrahydrofuran molecule. Electron paramagnetic resonance signals after different chlorinated low-pressure polyethylenes were measured. It was found that the signal intensity did increase linearly with the increase of chlorine groups in the polymer. A further study of the rate of decay of spin concentration at crystallization temperature yielded similar results. At this point, the hypothesis of negative ion formation during PVC irradiation reunified with the phenomenon of positive shift due to positive charge transfer in the above mixed solvent. We also studied the influence of a series of additives on the irradiation of PVC or cyclohexanone solution and found that the same additive did not work in both solutions. Triethylamine and diethyl ether promote the crosslinking of cyclohexanone solution, which may be the same as the “sensitization” of ions in the mixed solvent. Water, ethanol and acetic acid inhibit the crosslinking of cyclohexanone solution. The inhibitory effect of these substances on cross-linking may be similar to that of low-temperature radiation ion polymerization. A series of additives had little effect in the tetrahydrofuran solution, probably because the tetrahydrofuranic cations themselves greatly contributed to the crosslinking effect and therefore the effect of small amounts of additives was insignificant. Finally, the effects of various additives in PVC aqueous suspension were also studied.