The Development of Radiation-Resistant Insulators.
Abstract
The electrical properties of capacitor insulation (the critical component in ion- chamber, quartz-fiber dosimeters) were related to theories of conduction and dielectric relaxation in insulators. A GENERAL SURVEY REVEALED THAT A K2S2O8- initiated, emulsion-polymerized copolymer of styrene and alpha-methyl styrene had a uniquely rapid decay of conductivity following irradiation. The decay of conductivity resulted from removal of mobile charge carriers (identified as electrons or 'holes') by a polar phase uniformly dispersed through the polymer by association with sulfate chain ends. A recipe for polymerization of a styrene homopolymer having such trapping species was optimized for moisture sensitivity and fabrication characteristics. Rapid decay was also achieved by incorporation of organic phosphites in solution-cast plastic films. It was found that acid groups (methacrylic, maleic) copolymerized with styrene were without effect on postirradiation conductivity. Effective trapping was produced, however, by neutraliza-tion and incorporation of water or emulsifier. This demonstrated that trapping action was not associated with a unique chemical composition but with a strongly polar phase uniformly distributed through the polymer. (Author-PL)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1973
- Accession Number
- AD0757720
Entities
People
- M. J. Kelly
- W. W. Parkinson
Organizations
- Oak Ridge National Laboratory