ABSTRACT

Intumescent flame retardants for polyolefins have been familiar for many years. They have also been displayed repeatedly at FRCA conferences (1-3). Their mode of action is to form a protective layer consisting of a stable char in the event of fire. This action is based on the synergism of phosphorus compounds and nitrogen compounds. Its mechanism is actuated (4,5) when the temperature rises above a certain limit (usually in the region of 250 to 300°C). The protective layer forms as a barrier between the flames and the substances fueling the fire. It does so by chemical crosslinkage of the materials and simultaneous foaming, thereby preventing the fire from spreading further.