2011

Modifying Matrix Materials to Increase Wetting and Adhesion

Improvements are achieved at lower cost and without degradation of fibers.

In an alternative approach to increasing the degrees of wetting and adhesion between the fiber and matrix components of organic-fiber/polymer matrix composite materials, the matrix resins are modified. Heretofore, it has been common practice to modify the fibers rather than the matrices: The fibers are modified by chemical and/or physical surface treatments prior to combining the fibers with matrix resins — an approach that entails considerable expense and usually results in degradation (typically, weakening) of fibers.

The alternative approach of modifying the matrix resins does not entail degradation of fibers, and affords opportunities for improving the mechanical properties of the fiber composites. The alternative approach is more cost-effective, not only because it eliminates expensive fiber-surface treatments but also because it does not entail changes in procedures for manufacturing conventional composite-material structures.

The alternative approach is best described by citing an example of its application to a composite of ultra-high-molecular-weight polyethylene (UHMW-PE) fibers in an epoxy matrix. The epoxy matrix was modified to a chemically reactive, polarized epoxy nanomatrix to increase the degrees of wetting and adhesion between the fibers and the matrix. The modification was effected by incorporating a small proportion (0.3 weight percent) of reactive graphitic nanofibers produced from functionalized nanofibers into the epoxy matrix resin prior to combining the resin with the UHMWPE fibers. The resulting increase in fiber/matrix adhesion manifested itself in several test results, notably including an increase of 25 percent in the maximum fiber pullout force and an increase of 60–65 percent in fiber pullout energy. In addition, it was conjectured that the functionalized nanofibers became involved in the cross linking reaction of the epoxy resin, with resultant enhancement of the mechanical properties and lower viscosity of the matrix.

This work was done by Katie Zhong of North Dakota State University for Marshall Space Flight Center. For further information, contact Sammy Nabors, MSFC Commercialization Assistance Lead, at This email address is being protected from spambots. You need JavaScript enabled to view it.. Refer to MFS-32665-1

White Papers

Noncontact Differential Impedance Transducer
Sponsored by Kaman
The Aerospace Industry Takes a Fresh Look at Its Wire Harness Design Approach
Sponsored by Mentor Graphics
Tubing & Hose Buying Tips, Part 2
Sponsored by Newage Industries
How to Maximize Temperature Measurement Accuracy
Sponsored by VTI Instruments
Reverse Engineering
Sponsored by Servometer
10 Tips For Designing Silicone Medical Components
Sponsored by SMC

White Papers Sponsored By: