METHYL NADIMIDE RESINS - SYNTHESIS AND CHARACTERIZATION

This article describes the synthesis and characterization of several m ethyl nadimides end-capped resins based on tris (3-aminophenyl) phosph ine oxide. These resins were prepared by reacting methyl-5-norbornene 2,3-dicarboxylic anhydride (methyl nadic anhydride) (MNA), pyromelliti c dianhydride (PMDA)/3,3',4,4'-benzophenone tetracarboxylic acid dianh ydride (BTDA)/2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydr ide (6F), and tris (3-aminophenyl) phosphine oxide (TAP) in glacial ac etic acid/acetone. Structural characterization of the resins was done by elemental analysis, IR, and H-1-NMR. Thermal characterization of un cured resins using DSC and TGA techniques revealed an exothermic trans ition accompanied by a weight loss in the temperature range of 200-350 -degrees-C. Residual weight at 800-degrees-C in nitrogen was found to be 47-55%. Isothermal curing of the resins was done at 340-degrees-C f or 1 h in an air atmosphere. The cured resins were stable up to 400 +/ - 20-degrees-C. (C) 1994 John Wiley & Sons, Inc.