ABSTRACT
Radiation processing is relevant to the elds of materials and biomedical sciences. Applications are varied, including polymer processing (vulcanization of rubber latex, polymer recycling, lithography), food industry (sterilization), and medicine (sterilization and radiotherapy). The interaction of ionizing radiation with matter leads to the formation of reactive intermediates, free radicals, ions, and excited molecules. The subsequent stabilizing reaction paths result in fragment desorption (e.g., hydrogen abstraction), structural arrangements (e.g., crystallization), and/or formation of new bonds (e.g., cross-linking). The degree of these transformations depends on the structure/nature of the material and conditions of treatment before, during, and after irradiation. Several studies were
16.1 Introduction .......................................................................................................................... 381 16.2 Low-Energy Electron Interactions ........................................................................................ 382
16.2.1 Dissociative Electron Attachment ............................................................................ 383 16.2.2 Direct Dissociative Processes: Electronic Excitation, Nonresonant Dipolar
Dissociation, and Dissociative Ionization .................................................................384 16.3 Low-Energy Electron Reactions on Simple Molecules ........................................................ 386
16.3.1 Electron-Impact Chemistry ...................................................................................... 386 16.3.2 LEE Polymerization ................................................................................................. 386
16.4 LEE Modication of Polymers ............................................................................................. 387 16.4.1 Surface Modication ................................................................................................ 388
16.4.1.1 Lithography on Self-Assembled Monolayers ............................................. 388 16.4.1.2 Surface Property Modication .................................................................. 389
16.4.2 Degradation and Aging Processes ............................................................................ 391 16.4.2.1 Dielectric Aging ......................................................................................... 391 16.4.2.2 Biomedical Material Degradation ............................................................. 392
16.5 LEE Damage to DNA ........................................................................................................... 394 Acknowledgments .......................................................................................................................... 395 References ...................................................................................................................................... 395
performed with high-energy radiation (protons, electrons, ions, photons), but few reviews document the effects of low-energy radiation, especially those induced by low-energy electrons (LEEs). This chapter treats the reactions of LEEs (energy <200 eV) with different organic materials from simple molecules in the condensed phase to polymers including DNA. Contrary to high-energy electron irradiation applications, demonstrations of the potential of LEEs are quite limited in the condensed phase. In this chapter, we describe the processes involved between LEEs and condensed molecules in connection with possible applications in different elds. Special emphasis is placed on the ability of LEEs to limit unwanted reactions in the modication of organic molecules and polymers.
