Metal carboxylate additives for thermoplastics

1. A thermoplastic composition comprising a thermoplastic polymer and one or more ionic compounds, the one or more ionic compounds comprising a central metal element and one or more carboxylic acid functional moieties,

wherein the thermoplastic polymer is polyethylene, polypropylene, polybutene, ethylene-propylene rubber, polyisobutylene, a cyclopolyolefin, polyisoprene, a poly-alpha-olefin, or mixtures thereof,

wherein the one or more ionic compounds are metal salts of aromatic ring-containing carboxylic acids having one, two, or three aromatic rings,

wherein the one or more carboxylic acid functional moieties are selected from the group consisting of 1-naphthoic acid, 2-naphthoic acid, 9-anthracenecarboxylic acid, 3-phenanthrenecarboxylic acid, 4-phenanthrenecarboxylic acid, 9-phenanthrenecarboxylic acid, 1-napthalene acetic acid, 2-phenanthrenecarboxylic acid, cinnamic acid, hydrocinnamic acid, and phenylacetic acid, with either a substituted or unsubstituted aromatic ring, and mixtures thereof,

wherein the composition contains from 1% to about 10% of the one or more ionic compounds by weight of the composition and at least 90% of the thermoplastic polymer by weight of the composition,

and

wherein the central metal element is zinc.

2. The thermoplastic composition of claim 1 , wherein the composition contains from 1% to about 5% of the one or more ionic compounds by weight of the composition.

3. The thermoplastic composition of claim 1 , wherein the one or more ionic compounds are selected from the group consisting of zinc phenylacetate, zinc cinnamate, zinc hydrocinnamate, zinc naphthoate, zinc naphthalene acetate, and mixtures thereof.

4. A polymeric article having improved mechanical properties comprising the thermoplastic composition of claim 1 .

5. The polymeric article of claim 4 , wherein the article is an extruded, injection molded, cast, or pressed thermoplastic article.

6. A method of improving the mechanical properties of thermoplastics, the method comprising adding, to a thermoplastic composition comprising a polymer, an additive comprising one or more ionic compounds comprising a central metal element and one or more carboxylic acid functional moieties,

wherein the polymer is polyethylene, polypropylene, polybutene, ethylene-propylene rubber, polyisobutylene, a cyclopolyolefin, polyisoprene, a poly-alpha-olefin, or mixtures thereof,

wherein the one or more carboxylic acid functional moieties are selected from the group consisting of 1-naphthoic acid, 2-naphthoic acid, 9-anthracenecarboxylic acid, 3-phenanthrenecarboxylic acid, 4-phenanthrenecarboxylic acid, 9-phenanthrenecarboxylic acid, 1-napthalene acetic acid, 2-phenanthrenecarboxylic acid, cinnamic acid, hydrocinnamic acid, and phenylacetic acid, with either a substituted or unsubstituted aromatic ring, and mixtures thereof, and

wherein the one or more ionic compounds are aromatic ring-containing carboxylic acids having one, two, or three aromatic rings,

wherein the thermoplastic composition following addition of the one or more ionic compounds contains from 1% to about 10% of the one or more ionic compounds by weight of the composition and at least 90% of the thermoplastic polymer by weight of the composition, and

wherein the central metal element is zinc.

7. The method of claim 6 , wherein the polymer is polyethylene (PE) or polypropylene (PP).

8. The method of claim 6 , wherein the one or more ionic compounds are selected from the group consisting of zinc cinnamate, zinc hydrocinnamate, zinc naphthoate, zinc naphthalene acetate, and mixtures thereof.

9. The method of claim 6 , wherein the additive is combined with the polymer at conditions suitable to form a polymer matrix in which the one or more ionic compounds is homogeneously distributed within the polymer matrix.

10. The thermoplastic composition of claim 1 , wherein the thermoplastic polymer is polyethylene (PE) or polypropylene (PP).

11. A thermoplastic composition comprising a thermoplastic polymer and one or more ionic compounds, the one or more ionic compounds comprising a central metal element and one or more carboxylic acid functional moieties,

wherein the thermoplastic polymer is polyethylene, polypropylene, polybutene, ethylene-propylene rubber, polyisobutylene, a cyclopolyolefin, polyisoprene, a poly-alpha-olefin, or mixtures thereof,

wherein the one or more ionic compounds are metal salts of aromatic ring-containing carboxylic acids having one, two, or three aromatic rings,

wherein the one or more carboxylic add functional moieties are selected from the group consisting of 1-naphthoic add, 2-naphthoic acid, 9-anthracenecarboxylic acid, 3-phenanthrenecarboxylic acid, 4-phenanthrenecarboxylic acid, 9-phenanthrenecarboxylic acid, 1-napthalene acetic acid, 2-phenanthrenecarboxylic acid, cinnamic acid, hydrocinnamic acid, and phenylacetic acid, with either a substituted or unsubstituted aromatic ring, and mixtures thereof,

wherein the composition contains from 1% to about 5% of the one or more ionic compounds by weight of the composition, and

wherein at least a portion of the polymer is immobilized by the one or more ionic compounds without cross-linking or nucleation by the one or more ionic compounds.

12. The thermoplastic composition of claim 11 , wherein the one or more ionic compounds are selected from the group consisting of zinc phenylacetate, zinc cinnamate, zinc hydrocinnamate, zinc naphthoate, zinc naphthalene acetate, and their equivalents substituting calcium or magnesium instead of zinc as the central metal element, and mixtures thereof.

13. The thermoplastic composition of claim 11 , wherein the central metal element is zinc.

14. The thermoplastic composition of claim 11 , wherein the thermoplastic polymer is polyethylene (PE) or polypropylene (PP).

15. A polymeric article having proved mechanical properties comprising the thermoplastic composition of claim 11 .

16. The polymeric article of claim 15 , wherein the article is an extruded, injection molded, cast, or pressed thermoplastic article.