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电离輻射对于引发自由基机构的鏈式过程,特別是乙烯基单体的輻射聚合过程,是目前在化学上利用高能射綫最現实的方法之一。国外在这方面进行了大量的研究工作。約于1938～1940年开始研究的甲基丙烯酸甲酯和苯乙烯的輻射聚合,是研究得最早和最多的单体。輻射聚合与化学引发剂引发聚合相此較,具有許多独特的优点。如輻射聚合的引发速率与溫度无关,聚合过程可在低溫进行,其平均聚合度随溫度的升高而升高;高能射綫本身就是引发剂,可以制得高純度的聚合物;引发速率易于借輻射强度的調节而控制;輻射产生的自由基均匀地分布于整个系統,可以采用固相聚合等。研究表明,所有按自由基机构聚合的单体都能在高能射綫作用下聚合,在某种情况下,是唯一的方法。
Ionizing radiation is one of the most realistic methods for chemical utilization of high energy radiation at present for the chain polymerization initiating the free radical mechanism, especially the radiation polymerization of vinyl monomers. Abroad in this area conducted a lot of research work. Radiation polymerization of methyl methacrylate and styrene, which began around 1938-1940, was the earliest and most studied monomer. Radiation polymerization and chemical initiator-initiated polymerization in this phase, with many unique advantages. Such as radiation polymerization initiation rate has nothing to do with the temperature, the polymerization process can be carried out at low temperatures, the average degree of polymerization increases with increasing temperature; high-energy radiation itself is the initiator, you can get high purity polymers; By the regulation of radiation intensity and control; radiation generated by the uniform distribution of free radicals throughout the system, you can use solid-phase polymerization. Studies have shown that all monomers polymerized by free-radical mechanisms can polymerize under the action of high energy rays and in some cases the only method.