Flame-retarded polyolefin blend with good balance of properties

A flame-retarded polymeric composition comprising:

• a. a polymer blend consisting essentially of from 40 to 50 weight percent of a polypropylene having a melt flow in the range of 10 to 15 g/10 min. and a density in the range of 0.90 to 0.91 g/cc., 25 to 35 weight percent of a polyethylene having a melt flow index in the range of 15-20 g/10 min. and a density in the range of 0.950-0.960, and 20 to 30 weight percent of a substantially amorphous ethylene/propylene copolymer having a Mooney Viscosity ML (1 + 8 min.) at 260.degree. F in the range of 55-70 and a density of about 0.86 g/cc., having incorporated therein
• b. from 10 to 50 parts per 100 parts of said blend of a cured intumescent flame retardant comprising the reaction product of a phosphorus oxide of the formula P.sub.2 O.sub.5.xH.sub.2 O, wherein x is a number having a value of 0 to 3;
• a saturated acyclic polyol having from 5 to 15 carbon atoms and from 4 to 8 hydroxyl groups per molecule;
• a nitrogen compound selected from the group consisting of melamine, dicyandiamide, urea and dimethylurea;
• and, optionally, a color improving compound of the formula R--Y.sub.z, having from 2 to 24 carbon atoms per molecule, wherein Y is selected from the group consisting of --OH, --COOH --NR'.sub.2, z is a number having a value of 1 or 2, R is a hydrocarbyl radical having a valence of z selected from the group consisting of alkyl, cycloalkyl and alkoxy, and R' is --H or --R;
• which reaction product is thereafter cured by heating.