POLYOLEFIN INTUMESCENT PHOSPHOROUS FLAME RETARDANT SYSTEM

1 . A flame retardant polyolefin compound, comprising:

(a) ethylene vinyl acetate in an amount ranging from about 18 to about 23 weight percent of the compound;

(b) polypropylene copolymer in an amount ranging from about 21 to about 26 weight percent of the compound;

(c) ammonium polyphosphate in an amount ranging from about 35 to about 50 weight percent of the compound;

(d) magnesium hydroxide in an amount ranging from about 1 to about 2 weight percent of the compound;

(e) fluoroelastomer in an amount ranging from about 0.25 to about 0.35 weight percent of the compound;

(f) optionally, alpha-olefin copolymer in an amount ranging from 0 to about 12 weight percent of the compound; and

(g) optionally, N,N-ethylene bis-stearamide in an amount ranging from 0 to about 2 weight percent of the compound,

wherein the ammonium polyphosphate is treated with melamine and coated with an aliphatic thermoplastic polymer having amine group end groups.

2 . The compound of claim 1 , further comprising hindered phenolic antioxidant and phosphite stabilizer.

3 . The compound of claim 1 , further comprising colorant.

4 . The compound of claim 1 , further comprising adhesion promoters; antioxidants; biocides (antibacterials, fungicides, and mildewcides), anti-fogging agents; anti-static agents; bonding, blowing and foaming agents; dispersants; fillers and extenders; smoke suppressants; expandable char formers; impact modifiers; initiators; lubricants; micas; pigments, dyes; plasticizers; processing aids; other polymers; release agents; silanes, titanates and zirconates; slip and anti-blocking agents; stabilizers; stearates; ultraviolet light absorbers; viscosity regulators; waxes; and combinations of them.

5 . A molded article, comprising a compound of claim 1 .

6 . The molded article of claim 5 , in the form of a conduit for protecting cables that can carry transmissions.