Design and characterization of thermosetting polyimide structural adhesive and composite matrix systems

✍ Scribed by B. Tan; V. Vasudevan; Y. J. Lee; S. Gardner; R. M. Davis; T. Bullions; A. C. Loos; H. Parvatareddy; D. A. Dillard; J. E. McGrath; J. Cella

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 283 KB
• Volume: 35
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(199710)35:14<2943::aid-pola15>3.0.co;2-j

✦ Synopsis

Fully cyclized, organo soluble, phenylethynyl-terminated, ether-imide oligomers of 2-10,000 g/mol (M n ) were prepared by the reaction of 2,2-bis [4-(3,4-dicarboxyphenoxy)phenyl]-propane dianhydride (bisphenol-A dianhydride, BPADA) with a stoichiometric excess of either para, meta, or isomeric mixtures of phenylene diamine and phenylethynylphthalic anhydride (4-PEPA) endcapper. High para-containing oligomers produced semicrystalline powders, but the all meta isomer was completely amorphous. The lower molecular weight oligomers displayed an attractive low viscosity melt and were cured to very high gel content networks at 350-380ЊC for 30-90 min. The cured 3000 g/mol oligomers showed a (DSC) glass transition temperature ( T g ) of 267ЊC and produced tough, solvent-resistant films. Excellent adhesion to surfacetreated titanium alloys was achieved, as judged by single-lap shear measurements. Resin infusion molding was conducted, which permitted low-void, graphite-fabric composite panels to be prepared.