Accession Number : ADA302076

Title :   Thermally Stable Organic Polymers.

Descriptive Note : Final rept. 1 Feb 93-30 Jun 94,

Corporate Author : LOCKHEED AERONAUTICAL SYSTEMS CO MARIETTA GA

Personal Author(s) : Boschan, R. H. ; Marrocco, Matthew ; McGrath, James

PDF Url : ADA302076

Report Date : AUG 1994

Pagination or Media Count : 22

Abstract : Environmentally durable high temperature polymer matrix resins are critical in the design of near-term high performance supersonic aircraft. Currently available 6F based polymers are thermally stable, but are expensive and difficulty processable into void-free laminates. 3F polymers have demonstrated equivalent - thermal stability and processability, but are amenable to more facile, environmentally acceptable synthetic procedures. In the current program, Semi-Interpentrating Polymer Network (SIPN) blends of ethynyl and phenylethynyl terminated 3F polymers have been formulated, synthesized, and scaled up to quantities amenable to prepregging. Solution prepregging techniques were used by YLA, Inc., to fabricate 12" unidirectional prepreg tape. A series of test panels was fabricated from the IM7 prepreg tape, using dielectric monitoring procedures, from a 1:1 3F SIPN blend of phthalic anhydride terminated thermoplastic 3F oligomer with a phenylethynyl terminated 3F oligomer. Solution prepregging techniques were used to prepare unidirectional IM7 fiber prepreg tape. The primary goals of the program, including conception, synthesis development, scaleup, prepregging and panel fabrication, were all met. The void content of the laminates was somewhat higher than acceptable, probably due to the high melt viscosity and solvent inclusion. A plan, using powder prepregging, was offered to alleviate the void problem.

Descriptors :   *POLYMERS, *THERMAL STABILITY, *MATRIX MATERIALS, *POLYIMIDE RESINS, TEST AND EVALUATION, MONITORING, SYNTHESIS, LAMINATES, PANELS, DIELECTRICS, FABRICATION, MELTS, VOIDS, ORGANIC COMPOUNDS, HIGH VISCOSITY.

Subject Categories : Laminates and Composite Materials
      Polymer Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE