Polyphosphazenes

Polyphosphazenes, which contain alkoxy, aryloxy, and(or) fluoroalkoxy substituents, are commercial semi-inorganic polymers that are or will be marketed by Ethyl Corporation. Their flame retardancy and good mechanical, chemical, and thermal properties, make them suitable for applications such as O-rings, gaskets, wire coatings, fuel lines, and nonburning insulation materials.

On the basis of patent information, we estimate the total fixed capital investment for a 3 million Ib/yr (1,400 mt/yr) polyphosphazene plant to be about $19 million. The gross raw materials costs account for about 50% and 42% of the production cost and product value, respectively.