Thermal Oxidative Decomposition Studies of Neoprene Compositions

Abstract

Four neoprene compositions—uncured gum, known cured rubber, cable insulation, and hose conduit, the latter two used in underground miming—were subjected to thermal oxidative degradation under static and dynamic environments, and the volatile products were quantitated on a milligrams-per-gram basis. In a quiescent system at 370°C, no glow was observed, the extent of oxidation was low, up to 84% of the chlorine content was evolved as hydrogen chloride, ami the sulfur present was released largely in the form of carbon disulfide. Under more drastic conditions (higher temperatures and flowing air), glow occurred in several instances, resulting in an increased production of oxidation products as represented by CO₂, COS, SO₂, HCOOH, and CH₃COOH, among others. Thermogravimetiic investigations of the neoprene compositions show the first weight loss to correlate closely with hydrogen chloride evolution; furthermore, the use of thermogravimetric curves as means of material differentiation appears to offer a definite promise.