UPGRADING OF POLYMERIC MATERIALS FOR ELECTRICAL APPLICATIONS.
Abstract
The radiation crosslinking of polyethylene, polypropylene and an ethylene-propylene (predominantly polypropylene) copolymer has been studied with emphasis being placed upon thermal upgrading while simultaneously considering dielectric properties. Both Machine (Beta) and gamma (e.g., Co-60) radiation crosslink polyethylene, but the gamma process is more effective at lower doses in the presence of certain multifunctional monomers. The polypropylenes require small quantities of the polyfunctional monomers for crosslinking to be efficient. Allyl methacrylate, divinyl benzene and diallyl maleate are effective with polyethylene; the former is effective with the polypropylenes. The monomers have a negligible effect on dielectric constant or dissipation factor after gamma radiation to up to 8 Mrads in nitrogen; dielectric properties remain essentially unchanged after Machine irradiation to 40 Mrads in air. The crosslinked polyethylene exhibits improved tensile strength when measured under conditions wherein polymer crystallinity has been eliminated (temperatures above melting range of unirradiated polymer). (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 15, 1964
- Accession Number
- AD0463790
Entities
People
- Bruce S. Bernstein
- George Odian
- Sebastian Tirelli
- Sidney Binder