Assessment of relative flammability and thermochemical properties of some thermoplastic materials

Abstract
The thermochemical and flammability characteristics of some typical thermoplastic materials currently in use and others being considered for use in aircraft interiors are described. The properties studied included (a) thermal mechanical properties such as glass transition and melt temperature, (b) changes in polymer enthalpy by differential scanning calorimetry, (c) thermogravimetric analysis in an anaerobic and oxidative environment, (d) oxygen index, (e) smoke evolution, (f) relative toxicity of the volatile products of pyrolysis, and (g) selected physical properties. The generic polymers which were evaluated included: acrylonitrile‐butadiene‐styrene, bisphenol A polycarbonate, bisphenol fluorenone carbonate‐dimethylsiloxane block polymer, phenolphthalein‐bisphenol A polycarbonate, phenolphthalein polycarbonate, polyelher sulfone, polyphenylene oxide, polyphenylene sulfide, polyaryl sulfone; chlorinated poly vinyl chloride homopolymer, polyvinyl fluoride, and polyvinylidene fluoride. Processing parameters including molding characteristics of some of the advanced polymers are described. Test results and relative rankings of some of the flam inability, smoke and toxicity properties are presented. Under these test conditions, some of the advanced polymers evaluated were significantly less flammable and toxic or equivalent to polymers in current use. A relationship of the anaerobic char yield of the polymers to their relative flammability properties is shown.