The Role of Surface Functional Groups in Adhesive Bonding at the Aramid-Epoxy Interface,

Abstract

In polymeric composites, reactive functional groups on the fiber surface are assumed to greatly enhance the mechanical strength of the fiber-matrix interface by forming covalent bonds with the matrix. To test this assumption, we ought to promote covalent bonding at the aramid fiber-epoxy matrix interface by attaching flexible reactive pendent groups to the fiber surface. Other factors that could affect interfacial adhesion were kept constant, i.e., surface energy and surface topography. Quantitative analysis showed a pendent group attachment level of 1.5 to 4.5 groups per 100A sub 2 of fiber surface, a level that agrees well with the theoretical amount. Surprisingly, adhesive performance tests, the presence of these reactive pendent groups did not improve the fiber-matrix interface strength. Specific chemical tests for covalent bond formation between the terminal amine of the pendent group and the epoxy molecule showed that covalent bonding did not occur, thus explaining the unexpected lack of improvement in adhesive performance.

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Document Details

Document Type
Technical Report
Publication Date
Sep 15, 1986
Accession Number
ADA172998

Entities

People

  • L. S. Penn
  • T. J. Byerley
  • T. K. Liao

Organizations

  • MRIGlobal

Tags

Communities of Interest

  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Adhesion
  • Adhesive Bonding
  • Adhesives
  • Aramid Fibers
  • Chemical Reactions
  • Chemical Synthesis
  • Chemistry
  • Chlorides
  • Composite Materials
  • Covalent Bonds
  • Fibers
  • Filaments
  • Liquids
  • Materials
  • Materials Science
  • Military Research
  • Reinforced Plastics

Readers

  • Quantum Chemistry
  • Reinforced Composite Materials
  • Surface Coatings Technology.