Accession Number : AD0782213

Title :   Polymerization of Controlled Anisotropy Polymers on Graphite Fibers.

Descriptive Note : Final rept. Jan 72-Sep 73,


Personal Author(s) : Lando,Jerome B.

Report Date : NOV 1973

Pagination or Media Count : 58

Abstract : Graphite fiber reinforced polymeric composites containing oriented polymer matrices have been prepared by the in situ polymerization of monomers epitaxially crystallized onto the fiber surface. All crystallizable substances studied demonstrated an orienting effect such that the direction of most rapid growth corresponds to that of the fiber axis so as to maximize the interaction with the graphite crystal edges. The Nylon 66 system was of primary interest in this study. The monomer, whether oriented (crystallized from solution) or unoriented (deposited from an aqueous slurry) was found to polymerize to an oriented matrix in graphite fiber composites by a variety of polymerization techniques (spark discharge, resistance heating, and furnace heating). X-ray diffraction has demonstrated that the matrix morphology corresponds to the polymer chains aligning themselves parallel to the surface of the graphite fiber. Scanning electron microscopy of fracture surfaces has shown excellent adherence between the fiber and matrix, with fracture occurring mostly in the matrix material. Thus the use of the polymerization techniques developed in this study for the preparation of strongly adhering sizes and coatings for graphite fibers is indicated. Laboratory scale multi- fiber composites have been prepared for mechanical testing by a combination of the techniques described herein but the preliminary test results must be considered inconclusive until an improved procedure for preparing composites is developed. (Author-PL)

Descriptors :   *Fiber reinforced composites, *Carbon fibers, *Reinforced plastics, Nylon, Polymerization, Anisotropy, Orientation(Direction), Microstructure, Test methods

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE