Cure with high energy radiation

Curing of silicone mbbers can be done with high energy radiation such as gamma rays. 

Curing of rubbers is also aided by peroxides, metal oxides, amines, and derivatives and oximes, and other agents. High-energy radiation is also used, with appropriate chemicals. 

VDF-based fluoroelastomers can also be cured by different types of high-energy radiation (X-rays, y-rays, /3-particles or electrons). However, the generated free radicals can undergo several reactions, different from the crosslinking reaction (e.g., they can cause chain scission). This last one comes from the recombination between two macroradicals. Several properties vary with the radiation cure. For instance, the glass transition temperature, the gel fraction and the crosslinking density increase with the radiation dose. 

The photocuring of coatings is paralleled by high-energy radiation curing (see Section 5.6.4), which does not require initiators rather, the latter process is performed industrially with the aid of fast electrons. 

EVM elastomers belong to the group of rubbers with fully saturated backbone. As there are no sulfur-curable sites in the side-chain, they have to be cured radically by means of peroxides or high-energy radiation. 

The polymeric systems are usually composed of a polymer which Imparts the majority of physical properties and actinic additives. In simple systems such as curing films or electron beam resists, the polymer is also the radiation sensitive species. In most cases, the formulations behave simllarily in their response to high energy irradiation. Practically any polymer can be made radiation sensitive by direct exposure to ionizing energies or by formulation with additives such as free radical precursors. Thermally sensitive polymers are also likely to undergo a similar reaction when exposed. 

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