Application of In Situ Fiberization for Fabrication of Improved Strain Isolation Pads and Graphite-Epoxy Composites.

Abstract

An accelerated study has been performed to determine the feasibility of applying Hughes Aircraft Company's patented In Situ Fiberization (ISF) process to the fabrication of: (1) improved Strain Isolation Pads (SIPs) for the Space Shuttle, and (2) improved graphite/epoxy (GR/EP) composites. The ISF process involves the formation of interconnected polymer fiber networks by agitation of dilute polymer solutions under controlled conditions. Most previous work was performed using aliphatic hydrocarbon polymers which have limited high temperature capabilities. In Task 1 of the program, attempts were made to advance ISF technology by fiberization of high temperature polymers which would be suitable for SIP use. Progress was made toward that objective with the successful fiberization of polychlorotrifluoroethylene, a relatively high melting polymer. Attempts to In Situ Fiberize polymers with even greater thermal stability were not successful. The latter difficulty is presumed to derive from poor solubility, low molecular weight, and/or high chain stiffness, all caused by the presence of aromaticity in the backbone of such materials. During Task 2, two dimensional arrays of graphite fiber were interconnected with polypropylene In Situ Fibers. Following epoxy resin impregnation and lamination of the arrays into panels, mechanical property tests were performed to gauge the effectiveness of the In Situ Fibers for improvement in intralaminar shear strength, and hence fracture toughness. Test results were generally, though not universally, unpromising. Poor performance is believed to reflect incomplete In Situ fiber/resin wetting, poor graphite fiber packing, and perhaps low In Situ Fiber moduli. (MM)

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1982
Accession Number
ADA304649

Entities

People

  • Danute I. Basiulis
  • Robert W. Seibold
  • Robin W. Rosser

Organizations

  • Hughes Aircraft Company

Tags

Communities of Interest

  • Energy and Power Technologies
  • Space

DTIC Thesaurus Topics

  • Alkenes
  • Biomedical And Dental Materials
  • Composite Material Fabrication
  • Composite Materials
  • Epoxy Composites
  • Failure Mode And Effect Analysis
  • Fluoropolymers
  • Graphitic Materials
  • Laminates
  • Materials
  • Materials Laboratories
  • Materials Processing
  • Materials Testing
  • Mechanical Properties
  • Mechanics
  • Resins
  • Two Dimensional

Readers

  • Polymer Science and Engineering.
  • Polymer Science and Technology
  • Structural Health Monitoring of Composite Structures.

Technology Areas

  • Space