LOW-LOSS STYRENE-TYPE FOAM-IN-PLACE ENCAPSULATING RESINS,

Abstract

Low-dielectric-loss styrene-type foam-in-place encapsulating resins are not available commercially. Such a resin has now been developed. A propellant was added to the catalyzed styrene-polystyrene mixture; as the temperature of the polymerizing resin rose, the propellant expanded the resin into a cellular structure. Homogeneous foams were obtained in the presence of finely powdered polymers, which acted as bubble nucleators. The resultant rigid foams had dielectric constants ranging from 1.2 to 1.8, and loss tangents from 0.0002 to 0.001 over the frequency range 102 and 108 cps. Some of these materials had remarkably flat loss-frequency curves, losses ranging only between 0.0004 and 0.0005 over the same frequency range. Densities were varied between 0.194 and 0.850 g/cu cm, or between 12 and 53 lb/cu ft. These data indicate the usefulness of the new cellular materials as rf encapsulating resins. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 15, 1965
Accession Number
AD0628537

Entities

People

  • F. J. O. Engelhardt

Organizations

  • Harry Diamond Laboratories

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Biomedical And Dental Materials
  • Cellular Structures
  • Composite Materials
  • Dielectric Permittivity
  • Dielectric Polymers
  • Dielectrics
  • Films
  • Frequency
  • Materials
  • Plastics
  • Polymeric Films
  • Polymers
  • Polystyrenes
  • Propellants
  • Resins
  • Styrenes

Readers

  • Polymer Science and Engineering.