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SlESSION IV: NEW MATERIALS TECHNOLOGY SESSION OBJECTIVES Determine what new or alternative material technologies can lead to materials and assemblies that are significantly more thermally stable (or fire resistor. PARTIC~^TS Chair: John Rock, Amoco Committee: ScoH Campbell, McDonnell Douglas Takashi Kashiwagi, National Institute of Starboards and Technology lames McGrath, Virginia Polytechnic Institute Participants: Hans-Dieter Berg, Deutsche Aerospace Airbus Hanns-Ioerg Betz, Lufthansa German Airlines Alan Van Buskirk, General Plastics Kathryn Buder, National Institute of Starboards aM Technology Peter Guard, Boeing Commercial Airplane Group Jeff Gilman, National prostitute of Standards arm Technology Theo Klems, Airbus Ir~ustrzes Menachem Lewin, Polytechnic University Richard Lyon, Federal Aviation Administration Dale Onderak, Schneller, Inc Edward Weil, Polytechnic University William Weltner, M. C. Gilifoam Corporation SESSION REPORT State of the Art of Fir - Resistant Materials Most materials currently used in new construction in aircraft interiors significantly exceed regulatory requirements. While materials exist that may offer improved fire performance, implementation has been inhibited by unproven economic or technical feasibility. Current test methods show wide variability and are not predictive of large-scale performance. The results from these tests provide lithe guidance in the development of new materials or the improvement of existing materials. 240

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Part 11- Workshop Spry Materials Fire Performance Goals for Long-Term Research 241 Participants agreed that the current goal for long-term research should be to improve the fire performance of materials by an order of magnitude. Specific goals include: increasing fire resistance (e.g., reduce heat release to zero for 5-10 minutes at 35 kW/m2, external flux); delaying or preventing ignition; and minimizing toxic products dboth in processing/fabrication and burning). Other specific goals suggested by participants are to develop small-scale tests that better correlate to large-scale teses and to actual fire scenarios and to assess the benefit of improvements in fire performance of materials (i.e., perform cost-benefit analysis on potential improvements). Proni~ing Materials Technologies or Approaches In general, two approaches to more fire-resistant polymeric materials development are polymers with additives that make them fire resistant and fire-resistant polymers that possible: do not require auci~t~ves. Approaches that show particular promise include: thin, laminated or co-extruded films and blends, coatings and additives (especially intumescents), phase-change or temperature-sensitive ("intelligent") materials, organic-inorganic polymer blends, and polymer modifications. Needed Development in Materials Science and Characterization Methods In order to facilitate the development and commercialization of improved fire-resistant materials and structures, many of the group agreed to the following suggestions. Develop lower-cost processing and scale-up methods for existing specially materials. Develop processes and methods to incorporate reflective layers or coatings into structures. Advance the understanding and science base in the areas of ignition and char formation. Develop computational tools and models as guidelines for basic polymer science.

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242 Improved Fire- aM Smoke-Resistar~t Materials Long-Term Research Session participants suggested the following areas for long-term research. Develop a basic scientific understanding of char and intumescence. Include research in char formation, with investigations into the effects of atmosphere, heating rate, chemical der~vitization, additives, and coatings, as well as in char characteristics such as mechanical behavior (durability) and solid-state structure. Develop a basic scientific understanding of ignition behavior. Investigate development of improved materials for next-generation aircraft interiors. There are three directions for materials development: 3. Modification of engineering polymers such as polycarbonate, nylon, polyethyleneterephthalate, phenolic, and wool to improve fire resistance; these may represent the lowest-cost alternative. 2. Development of a greater understanding of thermal degradation mechanisms of specialty polymers (with or without additives) such as polyetheretherketone, polyetherimide, polyphenylenesulfide, and polysulfone; these should represent the best performance in the near term ~ ~ 10 years). Development of high-performance, thermally stable materials including organic-inorganic systems, copolymers, polymer blends and alloys, and glasses and ceramics; these represent the best performance in the long-term (>10 years). Research low-cost manufacturing technology for the "most-promising" materials. Give primary priority to composite fibers and thermoplastic and thermoses matrices; materials and processes from thermoplastic molding and thermoforming; decorative layers including varnishes, foils, and thermoplastics; foam-core materials and nonmetallic and aluminum honeycomb materials, textiles; and adhesives. Give secondary priority to transparencies; glass fiber, carbon fiber, and foam insulations; electronics; wire and cable; and elastomers.