STUDIES ON FLAME-RETARDANT INTUMESCENT CHAR .1.

In recent years the concept of intumescent (insulative foamed) char has received renewed attention as a means to flame retard materials. In particular, breakthrough enhancements in thermal stability and compatibility have provided the necessary capability to perform in thermoplastics, e.g. polypropylene, polyethylene (Refs 1 and 2). As part of our efforts to develop optimized intumescent flame retardant (IFR) product technology, a study of the influence on effective char formation by metal oxide pigments has been started. Initial results show the existence of both synergistic and antagonistic behavior. Chemical and physical interactions are proposed to explain these results.