Accession Number:

ADA172998

Title:

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

Descriptive Note:

Corporate Author:

MIDWEST RESEARCH INST KANSAS CITY MO

Personal Author(s):

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

Report Date:

1986-09-15

Pagination or Media Count:

29.0

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.

Descriptors:

• *POLYAMIDE PLASTICS
• *EPOXY COMPOSITES
• *ADHESIVE BONDING
• FIBERS
• QUANTITATIVE ANALYSIS
• PERFORMANCE TESTS
• INTERFACES
• MOLECULES
• POLYMERS
• COMPOSITE MATERIALS
• COVALENT BONDS
• REACTIVITIES
• MATRIX MATERIALS
• TOPOGRAPHY
• STRENGTH(MECHANICS)
• SURFACES
• AMINES
• STRENGTH(GENERAL)
• BONDING
• EPOXY COMPOUNDS
• CHEMICAL ANALYSIS
• ADHESIVES
• SURFACE ENERGY

Subject Categories:

• Polymer Chemistry
• Laminates and Composite Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE