Flame Resistant Polyolefin Compositions and Methods for Making the Same

A method for making a flame-retardant composition, comprising combining:

• (a) a copolymer comprising at least about 50 wt. % of propylene-derived units, and about 5-35 wt. % of units derived from at least one of ethylene or a C4-10 alpha-olefin,
• wherein the copolymer has a heat of fusion of about 75 J/g or less;
• (b) a flame retardant;
• and
• (c) forming a flame-retardant composition that satisfies the requirements of UL94, with a V2 rating.

A flame-retardant composition comprising:

• (a) at least about 40 wt. % of a copolymer, wherein the copolymer comprises at least about 50 wt. % of propylene-derived units, and about 5-35 wt. % of ethylene-derived units, and has a heat of fusion of about 75 J/g or less, a melting point of about 100° C. or less, a crystallinity of about 2% to about 65% of isotactic polypropylene, and a Melt Flow Rate of about 1-10 dg/min (ASTM 1238, 230° C./2.16 kg);
• (b) about 20-40 wt. % of a flame retardant,
• wherein the flame-retardant composition satisfies the requirements of UL94, with a V0 rating, and has:
• (a) a Shore A hardness of about 60.0-90.0;
• (b) an Ultimate Tensile Strength of at least about 5 mPa;
• and
• (c) an Ultimate Elongation of at least about 600%.