The role of energy transfer on electron beam exposure of mixtures

Industrial processes utilizing electron beams for curing of coatings, sterilization, etc., almost always involve exposure of a mixture of substances. A pertinent example is the curing of coatings by an electron beam induced free radical polymerization. Here, the rate of the polymerization depends on the efficient use of the absorbed dose to form free radicals for the initiation of the polymerization. The initiator, usually a multifunctional acrylate, is only one component of a mixture of chemicals which ultimately change in some form, chemical or physical, to produce the final desired coating. In the experiments described in this report it is shown that the electron beam sensitivity of a component in a mixture may be dramtically altered by changing its concentration. These results indicate energy may be transferred between the components of a mixture and in order for one component, say a free radical initiator, to obtain most of the dose care must be taken in the formulation of the product. © 1985.