Radiation curing's characteristics:
　　 Radiation curing is a kind of newly emerging process technology that developed in recent years. Because the radiation
curing has low energy consumption, high production efficiency, low curing temperature, convenient operation, pollution free and so on advantages and because it is better than the heat curing and the light curing, so it has become the one which has the quickest development in the radiation processing.
　　 In the research for the radiation curing, the research for the Electron Beam Curing that caused by the cation has become the hot topic. That is because the cation caused EB Curing has the following advantages and characteristics: 
(1)Extremely small volume shrinkage;
(2)Has good cementing property with most of the plastics and metals, also has very high flexibility;
(3)The sample after curing has no odor; 
(4)Few extractable substances; 
(5)Insensitive to the O2, CO2 and so on gases; 
(6)The positive ion can maintain the activity after being irradiated.
　　 Using the EB irradiation to initiate the multi functional acrylate or methacrylate's monomer and oligomer has already become a relatively mature technology, especially on the coat curing. But the research about the cation caused EB Curing in our country is very few, until recent years, some units began to do research on it. 
　　 Recently, similar to the coating, printing ink, adhesive and foam curings, the resin compound's electron beam curing has become an important technology in the practical application. The high power electron beam curing has higher output proportion but lower energy request than the heat curing. The compound obtained by heat curing is typical high stress substance, so its mechanical properties reduced. Contrarily, the compound obtained by electron beam curing only has very low residual stress.
　　 Though the electron beam cured compound has many advantages, only several kinds of substances are suitable for the purpose now. Later, people found a kind of compound that can effectively produce acid with high quantum yield under ultraviolet light or visible light irradiation. Such a discovery opened the new domain of light initiating positive ion polymerization and condensation, especially for the important application on the coating, adhesive and printing ink. These compounds is stable to light and do not cause the thermal booster reaction with the monomer. 
　　
　　 One of the important characteristics of the cationic polymerization technique is the use of acid. This kind of acid has the anion that has very low nucleophilicity and can not terminate the polyreaction. Therefore, most of the cationic initiators are based on having the non-nucleophilic anion, such as the BF4-, PF6-, SbF6- and so on anions' salt.