NOVEL FLAME RETARDANT GLASS REINFORCED EPOXY COMPOSITES CONTAINING INTERACTIVE INTUMESCENT AND FLAME RETARDANT FIBRE

摘要

Glass reinforced polymer composite materials are susceptible to combustion and fire damage because of their organic matrix component. Many such structures are layered and thus tend to burn in layers. The heat impinging on the surface causes degradation of the resin thus leading to its ignition. Further penetration of the heat below the first glass layer causes degradation of the underlying resin. The degradation products migrate to the burning zone through the glass and any char retained in the glass. This process goes on until all layers of the resins are burnt. However, if the char formation can be enhanced which can then act as a thermal barrier, it can slow down this migration resulting in stopping or slowing down burning. In previous work it was observed that phosphate based intumescents interact with flame-retardant cellulosic fibres during the application of heat and form a complex 'char-bonded' structure. The char formed is greater in mass, resistant to oxidation, has better thermal barrier properties and higher mechanical strength compared to individual components. This work was extended to enhance char formation of thermoset (epoxy, phenolic and polyester) resins used in glass -reinforced rigid composites. When studied by thermal analytical techniques, it has been observed that the introduction of an intumescent/flame retardant fibre to these resins results in physical and chemical interaction of three components leading to enhanced char formation. The results indicated that laminates produced from these components should have superior flame-retardant properties. The intumescent /FR fibre combinations may be introduced either as a pulverized additive to the resin or as an additional textile fabric layer to the composite structure.