Dielectric properties of fluorine-containing polymethylsiloxane-imide films

Huimin Wang, Xiaoming Tao, Edward Newton

Research output: Journal article publicationJournal articleAcademic researchpeer-review

8 Citations (Scopus)

Abstract

The dielectric properties, dielectric relaxation behavior, electric conduction and kinetic characteristics of fluorine-containing polysiloxane-imide were investigated. The fluorine-containing polyimide [6FDA + p-PDA] has a low dielectric constant of 3.04, compared to normal polyimides such as Upilex-S [BPDA + p-PDA] with a dielectric constant of 3.47, due to the addition of perfluoroalkyl groups into the polymer backbone, while fluorine-containing polysiloxane-imide (6FDA + siloxane) has the lowest dielectric constant of 2.43, which is less than 2.5. The introduction of siloxane groups on the fluoric polyimides provides the possibility of obtaining high-performance polyimides with ultralow dielectric constants. The dielectric relaxation spectra suggest that the fluorine-containing polysiloxane-imide (6FDA + siloxane) has a phase separation structure. As frequency increases, the α relaxation strengths decrease and the β relaxation strengths hardly change. The conduction study indicates that the β peak corresponds to the β dipolar relaxation whereas the α one is due to the conductive effects in the bulk and the α dipolar relaxation. The activation energy of the α transition decreases with increasing frequency, while the activation energy of the β transition does not vary with frequency.
Original languageEnglish
Pages (from-to)271-283
Number of pages13
JournalHigh Performance Polymers
Volume14
Issue number3
DOIs
Publication statusPublished - 1 Jan 2002

Keywords

  • Dielectric relaxation behavior
  • Electric conduction and kinetic characteristics
  • Fluorine-containing polysiloxane-imide
  • Ultralow dielectric constant

ASJC Scopus subject areas

  • Polymers and Plastics
  • Organic Chemistry
  • Materials Chemistry

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