Synergistic Formation of Radicals by Irradiation with Both Vacuum Ultraviolet and Atomic Hydrogen: A Real-Time In Situ Electron Spin Resonance Study

Abstract

We report on the surface modification of poly(tetrafluoroethylene) (PTFE) as an example of soft materials and biomaterials that occur under plasma discharge by kinetics analysis of radical formation using in situ real-time electron spin resonance (ESR) measurements. During irradiation with hydrogen plasma, simultaneous measurements of the gas-phase ESR signals of atomic hydrogen and the carbon dangling bond (C-DB) on PTFE were performed. Dynamic changes of the C-DB density were observed in real time, where the rate of density change was accelerated during initial irradiation and then became constant over time. It is noteworthy that C-DBs were formed synergistically by irradiation with both vacuum ultraviolet (VUV) and atomic hydrogen. The in situ real-time ESR technique is useful to elucidate synergistic roles during plasma surface modification.

Ammonia plasma treatment as a method promoting simultaneous hydrophilicity and antimicrobial activity of viscose wound dressings

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Grafting Polytetrafluoroethylene Micropowder via in Situ Electron Beam Irradiation-Induced Polymerization

“…Among the techniques used to modify PTFE, high-energy irradiation such as plasma, ion beam, gamma ray, X ray, vacuum ultraviolet, and electron beam, are efficient and controllable [27,28,29,30,31,32]. No initiator or catalyst is required and a large-scale production without affecting the bulk properties can be achieved for meeting the criteria of practical applications.…”

Preparation and characterization of nanometer‐thin freestanding polymer foils for laser‐ion acceleration

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