Method for making a polymer composition

A method for making a polymer composition comprising the steps of (1) mixing (a) phosphate ester anions, (b) aromatic carboxylate anions, (c) cycloaliphatic dicarboxylate anions, (d) aluminum (III) cations, (e) sodium cations, (f) optionally, lithium cations, (g) optionally, zinc (II) cations, and (h) optionally, calcium cations to produce an additive composition, and (2) melt mixing the additive composition and a polypropylene polymer to produce a polymer composition, wherein:

• (i) the polypropylene polymer is selected from the group consisting of polypropylene homopolymers, polypropylene copolymers, and mixtures thereof;
• (ii) the phosphate ester anions conform to the structure of Formula (I)
• wherein R1 and R2 are independently selected from the group consisting of hydrogen and C1-C18 alkyl groups, and Rs is an alkanediyl group;
• (iii) the cycloaliphatic dicarboxylate anions conform to the structure of Formula (X)
• wherein R10, R11, R12, R13, R14, R15, R16, R17, R18, and R19 are independently selected from the group consisting of hydrogen and C1-C9 alkyl groups;
• (iv) the phosphate ester anions are present in the additive composition in an amount of about 5 mol. % to about 40 mol. % of the total amount of phosphate ester anions, aromatic carboxylate anions, and cycloaliphatic dicarboxylate anions present in the additive composition;
• (v) the aromatic carboxylate anions are present in the additive composition in an amount of about 20 mol. % to about 60 mol. % of the total amount of phosphate ester anions, aromatic carboxylate anions, and cycloaliphatic dicarboxylate anions present in the additive composition;
• (vi) the cycloaliphatic dicarboxylate anions are present in the additive composition in an amount of about 5 mol. % to about 55 mol. % of the total amount of phosphate ester anions, aromatic carboxylate anions, and cycloaliphatic dicarboxylate anions present in the additive composition;
• (vii) the aluminum (III) cations are present in the additive composition in an amount of about 5 mol. % to about 15 mol. % of the total amount of aluminum (III) cations, sodium cations, lithium cations, zinc (II) cations, and calcium cations present in the additive composition;
• (viii) the sodium cations are present in the additive composition in an amount of about 30 mol. % to about 95 mol. % of the total amount of aluminum (III) cations, sodium cations, lithium cations, zinc (II) cations, and calcium cations present in the additive composition;
• (ix) the lithium cations, if present, are present in the additive composition in an amount of about 0.5 mol. % to about 30 mol. % of the total amount of aluminum (III) cations, sodium cations, lithium cations, zinc (II) cations, and calcium cations present in the additive composition;
• (x) the zinc (II) cations, if present, are present in the additive composition in an amount of about 0.1 mol. % to about 15 mol. % of the total amount of aluminum (II)) cations, sodium cations, lithium cations, zinc (II) cations, and calcium cations present in the additive composition;
• (xi) the calcium cations, if present, are present in the additive composition in an amount of about 5 mol. % or more of the total amount of aluminum (III) cations, sodium cations, lithium cations, zinc (II) cations, and calcium cations present in the additive composition;
• and
• (xii) the additive composition contains 5 wt. % or more fatty acid salts selected from the group consisting of alkali metal, alkaline earth metal, and zinc (II) salts of saturated and unsaturated fatty acids.