Cyanate ester clay nanocomposites: synthesis and flammability studies: Fid-Bau Portal

Cyanate ester clay nanocomposites: synthesis and flammability studies

Gilman, J.W. / Harris, R. jun. / Hunter, D.

New goals outlined by the U.S. Federal Aviation Administration (FAA) Advanced Fire-Safe Aircraft Materials Research Program (1, 2) enumerate an order-of-magnitude improvement in aircraft cabin-material fire safety. In the pursuit of improved approaches to the design of ultrafire-safe aircraft interior materials, a wide variety of concerns must be addressed in addition to flammability. For many polymers used in the interior of aircraft cost is a major concern for aircraft manufacturers. Therefore, an additive approach to improving the fire safety of polymers is attractive. The additives must be inexpensive and easily processed with the polymer. In addition, the additive must not excessively degrade the other performance properties of the polymer, and it must not create environmental problems when recycling or at the time of its final disposal. We have recently found that polymer layered-silicate (clay) nanocomposites have the unique combination of improved flammability properties, and improved physical properties as well as recyclability. We report here on the use of a layered silicate, montmorillonite clay, dispersed at the nanometer level, in cyanate ester resins for improving flammability. We show that the use of melamine-treated montmorillonite in these resins yields exfoliated montmorillonite in the cured cyanate ester nanocomposites. This reduces the peak heat release rate by over 50%. We anticipate that this nanocomposite approach would be especially useful in improving toughened cyanate ester resins since the typical toughening agents used often increase the flammability and lower the modulus.