Accession Number : ADA307288

Title :   Development of Polyphenylquinoxaline Graphite Composites.

Descriptive Note : Rept. for 1 Jul 71-30 Sep 72,

Corporate Author : BOEING CO SEATTLE WA

Personal Author(s) : Hoggatt, J. T. ; Hergenrother, P. M. ; Shdo, J. G.

PDF Url : ADA307288

Report Date : JAN 1973

Pagination or Media Count : 141

Abstract : The potential of polyphenylquinoxaline (PPQ)/graphite composites to serve as structural material at 316 deg C (600 deg F) has been demonstrated using a block copolymer, BlCo(l :3), PPQ derivative. Initially, thirteen polyphenylquinoxalines were evaluated. From this work, four candidate polymers were selected for preliminary evaluation as matrices for HMS graphite fiber reinforced composites. The preliminary composite evaluation enabled selection of one of the four polymers for advanced composite preparation and testing. Using an experimentally established cure schedule for each of the four polymers, preliminary laminates of 50% resin volume content, prepared without postcure, were tested for flexure strength and modulus, interlaminar shear strength (short beam), and tensile strength and modulus at ambient temperature. A block copolymer (Bl Co 1:3) derived from one mole p-bis (phenylglyoxalyl) benzene, one fourth mole 3,3'-diaminobenzidine and three-fourths mole 3,3', 4,4'-tetraminobenzophenone was selected for extensive study. Tensile, flexural, and interlaminar shear values were obtained after aging and testing postcured BlCo(1:3) laminates at 316 deg C (600 deg F). The potential of PPQ/graphite laminates to serve as short term structural materials at temperatures up to 371 deg C (700 deg F) was demonstrated through weight loss experiments.

Descriptors :   *COMPOSITE MATERIALS, *BLOCK COPOLYMERS, *GRAPHITED MATERIALS, TEST AND EVALUATION, TENSILE STRENGTH, BENZENE, PREPARATION, POLYMERS, LAMINATES, FIBER REINFORCED COMPOSITES, GRAPHITE, CARBON FIBERS, FLEXURAL STRENGTH, CURING, PHENYL RADICALS, LAMINAR FLOW, WEIGHT REDUCTION, SHEAR STRENGTH, QUINOXALINES.

Subject Categories : Polymer Chemistry
      Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE