Interaction Between Microorganisms and Polymers Used for Layering in the Electronic Industry.

Abstract

Microbial degradation of electronic insulation polyimides has been evaluated using electrochemical impedance spectroscopy (EIS). A fungal consortium isolated from degrading polyimides, was used in this study. Degradation of polyimide films was observed during incubation, showing two steps of development. The Bode magnitude, the phase angle, and the Nyquist plots were all in good agreement with the data obtained. The first reaction resulted in penetration of water and solutes into the polymer matrix during the early stage of polymer-water contact. This was followed by the deterioration of the polymer, indicated by a large decrease of impedance in the Bode magnitude, progressive bending in the phase angle, and the appearance and compression of the semicircles in the Nyquist plots. These reactions strongly suggest polymer degradation and delamination. However they were not observed with sterile control EIS cells. The three fungi isolated and identified, Aspergillus versicolor, Cladosporidium cladosporidae and a Chaetomium species, are commonly found environmental contaminants. Our results suggest that polyimides used in the electronic industry are susceptible to microbial degradation.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Oct 10, 1995
Accession Number
ADA300916

Entities

People

  • Ralph Mitchell

Organizations

  • Harvard University

Tags

Communities of Interest

  • Advanced Electronics
  • Air Platforms

DTIC Thesaurus Topics

  • Aging (Materials)
  • Biodegradation
  • Carbon Fibers
  • Cells
  • Composite Materials
  • Electron Microscopes
  • Electron Microscopy
  • Fiber Reinforced Composites
  • Fungi
  • Material Degradation Processes
  • Materials
  • Materials Laboratories
  • Microorganisms
  • Microscopy
  • Polymeric Films
  • Polymers
  • Scanning Electron Microscopy

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Microbial Pathology
  • Surface Coatings Technology.

Technology Areas

  • Biotechnology
  • Microelectronics