Effects of Triethyl Phosphate (TEP) and Clay Addition on the Morphological, Compressive Strength and Flame Retardancy of Polyurethane (PU) Foam

Abstract

Polyurethane (PU) is a polymeric material with great mechanical properties and wide-ranging engineering applications. This material can be tailor made to flexible, rigid or a combination of both depending on the formulation. However, this material is easy to ignite because of its high flammability, releasing a high rate of heat when exposed to a heat source. Thus, research and development to improve the performance of rigid PU always are continuous in industries and the academe. Methods to develop new materials or improve existing techniques are always driven by cost effectiveness and the sustainability of materials used. The addition of a filler to enhance PU mechanical properties and its characteristic is a promising method to meet the objective. In this study, the potential of clay from natural resources originating from ball-clay type was investigated to determine its compatibility within PU foam formulation and its interaction with the conventional nonhalogen base retardant triethyl phosphate (TEP). Samples were prepared in three groups The first consisted of PU mix with TEP at 3%, 5% and 7% loading; the second group consisted of PU mix with fixed TEP at 3% and clay loading at 3%, 5% and 7%; and the third group had TEP loading set at 5% and clay loading varied at 3%, 5% and 7%. The compressive strength, morphology and flame-retardant properties of PU foams were analysed by scanning electron microscopy, vertical flame test, density test and compressive test.