Electron-beam-cured materials

Because of the precise control of the degree of cross-linking attainable by the electron beam process, it is well suited for the production of PSAs. Recent developments in EB design, particularly lower voltage, and materials developments have made electron beam curing of pressure-sensitive adhesives affordable, practical, and possible. ... 

NORRIS, ROBERT E. SCHULZ, M. D. Selection of Materials to be Utilized in Fabrication Tooling for Electron-Beam Curing of Composites. Proceedings of the 28th International SAMPE Technical Conference, vol. 28, (1996) 890. 

KINSTLE Electron-Beam Curing of Polymeric Materials... 

A facile method by which organic thin films may be readily coated upon substrates employs the electron beam curing of materials such as of monomeric and/or oligomeric acrylates and methacrylates. The perfluorinated acrylates 2-(N-butylperfluorooctanesulfonamido)ethyl acrylate (BFOSA), 2-(N-ethylperfluorooctanesulfonamido)ethyl acrylate (EFOSA), and perfluoropolyether diacrylate (PFEDA) were obtained from the 3M corporation, St. Paul, Minnesota 1,6-Hexanediol diacrylatc (HDODA) was obtained from Interez, Inc., Louisville, Kentucky. 

Kinstle, IF. 1990. Electron beam curing of polymeric materials. Materials development. In Radiation Curing of Polymeric Materials, eds. C. E. Hoyle and 1. F. Kinstle. ACS Symposium Series 417, Washington, EKl American Chemical Society, pp. 18-28. 

It has been shown that in many cases for thermoset systems, there is a quantitative relationship between the chemical conversion of the thermoset and its Tg value, independent of the time-temperature cure history (111). This is very convenient from an applications standpoint because measurement of Tg is equivalent to a direct measurement of conversion. It implies that either the molecular structure at a given degree of conversion is the same, regardless of the reaction path, or that differences in the structures produced for different reaction paths do not affect Tg. While a Tg-degree of cure relationship has been found valid for many epoxy-amine and other thermoset materials, it has been observed not to hold in some cases, which include some epoxy-DICY, cyanate-ester, and phenolic systems. It has also been found not to hold for a given resin system cured by two different methods such as thermal and microwave (112) or thermal and electron beam cures (113). 

Electron beam curing EB curable adhesives use the radiation of an electron beam to initiate curing. The electron beam has the advantage that it can penetrate through material that is opaque to UV light... 

Abstract In this chapter, classification of adhesive and sealant materials is presented. For this purpose, various categories are considered depending on the polymer base (i.e., natural or synthetic), functionality in the polymer backbone (i.e., thermoplastic or thermoset), physical forms (i.e., one or multiple components, films), chemical families (i.e., epoxy, silicon), functional types (i.e., structural, hot melt, pressure sensitive, water-base, ultraviolet/ electron beam cured, conductive, etc.), and methods of application. The classification covers high-temperature adhesives, sealants, conductive adhesives, nanocomposite adhesives, primers, solvent-activated adhesives, water-activated adhesives, and hybrid adhesives. 

Silicone acrylates (Fig. 5) are again lower molecular weight base polymers that contain multiple functional groups. As in epoxy systems, the ratio of PDMS to functional material governs properties of release, anchorage, transfer, cure speed, etc. Radiation induced radical cure can be initiated with either exposure of photo initiators and sensitizers to UV light [22,46,71 ] or by electron beam irradiation of the sample. 

Coating materials may be based on short or medium-oil alkyds (e.g. primers for door and window frames) nitrocellulose or thermoplastic acrylics (e.g. lacquers for paper or furniture finishes) amino resin-alkyd coatings, with or without nitrocellulose inclusions, but with a strong acid catalyst to promote low temperature cure (furniture finishes) two-pack polyurethanes (furniture, flat boards) unsaturated polyester resins in styrene with free-radical cure initiated by peroxides (furniture) or unsaturated acrylic oligomers and monomers cured by u.v. radiation or electron beams (coatings for record sleeves paperback covers, knock-down furniture or flush interior doors). 

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