Highly-resilient thermoplastic compositions

1. A golf ball comprising a cover and a core, said core comprising

a) an acid copolymer of the composition E/X/Y wherein E represents copolymerized residues of ethylene, X represents copolymerized residues of an α,β ethylenically unsaturated carboxylic acid, and Y represents copolymerized residues of a C 1 -C 8 alkyl acrylate or alkyl methacrylate, and further wherein the amount of X is 4-35 wt. % of the acid copolymer, and the amount of Y is 0-50 wt. % of the acid copolymer;

b) about 10 to about 45 wt. % of a high molecular weight, monomeric organic acid or salt thereof based on total weight of components a), b), and c) provided that component (b) does not exceed 50 wt. % of (a) plus (b);

c) about 1 to about 35 wt. % of a thermoplastic resin;

d) a cation source present at a level sufficient to neutralize 95 to 110% of the combined acid content of components a) and b); and

e) zero to about 60 wt. % of a filler based on weight of components a) plus b) plus c) plus e);

wherein the filler (e) is present in a type and amount sufficient to achieve a density between the density of the composition without filler and 1.8 grams per cubic centimeter; and

wherein the core has a dimple pattern such that when positioned in the ball and covered by the cover having a dimple pattern, the cover thickness in the dimple areas is the about the same as the cover thickness in the non-dimpled areas.

2. A center, core, or mantle of a golf ball or a one-piece golf ball, said center, core mantle or one-piece golf ball comprising

a) an acid copolymer of the composition E/X/Y wherein E represents copolymerized residues of ethylene, X represents copolymerized residues of an α,β ethylenically unsaturated carboxylic acid, and Y represents copolymerized residues of a C 1 -C 8 alkyl acrylate or alkyl methacrylate, and further wherein X is present in an amount of 4-35 wt. % of the acid copolymer, and Y is present in a finite amount up to 50 wt. % of the acid copolymer;

b) about 10 to about 45 wt. % of a high molecular weight, monomeric organic acid or salt thereof based on total weight of components a), b), and c) provided that component (b) does not exceed 50 wt. % of (a) plus (b);

c) about 1 to about 35 wt. % of a thermoplastic resin;

d) a cation source present at a level sufficient to neutralize about 50 to about 110% of the combined acid content of components a) and b); and

e) zero to about 60 wt. % of a filler based on weight of components a) plus b) plus c) plus e).

3. The center, core, or mantle of a golf ball or the one-piece golf ball of claim 2 wherein the thermoplastic resin is selected from the group consisting of copolyetheresters, copolyetheramides, elastomeric polyolefins, styrene diene block copolymers, polyurethanes, polyamides, polyesters, polyolefins, ethylene copolymers, anhydride modified ethylene or propylene homopolymers and copolymers, and metallocene polyethylene.

4. The center, core, or mantle of a golf ball or the one-piece golf ball of claim 2 wherein the thermoplastic resin is a thermoplastic elastomer.

5. The center, core, or mantle of a golf ball or the one-piece golf ball of claim 4 wherein the thermoplastic elastomer is selected from the group consisting of copolyetheresters, copolyetheramides, elastomeric polyolefins, styrene diene block copolymers and thermoplastic polyurethanes.

6. The center, core, or mantle of a golf ball or the one-piece golf ball of claim 2 wherein the filler (e) is present in a type and amount sufficient to achieve a density between the density of the composition without filler and 1.8 grams per cubic centimeter.

7. A multi-layer golf ball having a core and a cover with one or more intermediate layers or mantles between the core and the cover, the core and the mantles being independently or both selected from the cores and mantles of claim 6 wherein the filer is sufficient to adjust the density of the core or mantle or both in which the composition is used to a level such that the golf ball has a density of 1.14 gms/cc.

8. The multi-layer golf ball of claim 7 wherein the mantle(s) and the core independently or both comprise an acid copolymer (a) selected from ethylene acrylic acid and ethylene methacrylic acid, about 10 to about 30 wt. % of monomeric organic acid or salt thereof (b) based on weight of (a), (b) and (c), about 1 to about 35 wt. % thermoplastic resin (c) based on weight of (a), (b) and (c), and up to 60 parts filler (e) per hundred parts of (a) through (d) by weight.

9. A two-piece golf ball comprised of a core of claim 6 and a cover wherein the filler is sufficient to adjust the density of the core to about 1.18 gm/cc.

10. A two-piece golf ball comprising a cover and a core according to claim 6 , wherein the core has a dimple pattern such that when positioned in the ball and covered by the cover having a dimple pattern, the cover thickness in the dimple areas is the about the same as the cover thickness in the non-dimpled areas.