Golf balls with cores or intermediate layers prepared from highly-neutralized ethylene copolymers and organic acids

1. A golf ball comprising a core and a cover and optionally at least one intermediate layer positioned between the core and the cover, wherein the core or the intermediate layer when present comprises or is prepared from a thermoplastic composition, said thermoplastic composition optionally comprising a filler; wherein the thermoplastic composition has a PGA compression greater than 100; and further wherein the thermoplastic composition when formed into a sphere of 1.50 to 1.68 inches in diameter has a coefficient of restitution, said coefficient of restitution being measured by firing the sphere at an initial velocity of 125 feet/second against a steel plate positioned 3 feet from the point where initial velocity is determined and dividing the velocity of rebound from the plate by the initial velocity; wherein the coefficient of restitution is equal to or greater than 0.860 when the thermoplastic composition does not comprise filler; wherein the coefficient of restitution is equal to or greater than 0.830 when the thermoplastic composition comprises filler;

wherein the thermoplastic composition comprises or is prepared from:

(a) at least one aliphatic, monofunctional organic acid having 4 to 36 carbon atoms, wherein the longest carbon chain of the acid is optionally substituted with from one to three substituents independently selected from C 1 to C 8 alkyl groups;

(b) an ethylene acid copolymer consisting essentially of copolymerized comonomers of ethylene and from 19 to 21 weight % of copolymerized comonomers of at least one C 3 to C 8 α,β ethylenically unsaturated carboxylic acid, based on the total weight of the ethylene acid copolymer, said ethylene acid copolymer having a melt index from about 200 to about 600 g/10 minutes measured before neutralization according to ASTM D1238 at 190° C. using a 2160 g weight; and

wherein the combined acid moieties of (a) and (b) are nominally neutralized to a level from about 120% to about 200%.

2. The golf ball of claim 1 wherein the coefficient of restitution is equal to or greater than 0.870.

3. The golf ball of claim 1 wherein the organic acid is present in from about 35 to about 46 weight % of the total composition.

4. The golf ball of claim 1 wherein the organic acid comprises a linear, unsaturated organic acid having from 16 to 24 carbon atoms.

5. The golf ball of claim 4 wherein the organic acid comprises oleic acid.

6. The golf ball of claim 1 wherein the C 3 to C 8 α,β ethylenically unsaturated carboxylic acid is acrylic acid or methacrylic acid or a combination of acrylic acid and methacrylic acid.

7. The golf ball of claim 1 wherein the thermoplastic composition comprises filler; or wherein the golf ball has a cover prepared from a polyurethane composition or an ionomer composition.

8. The golf ball of claim 7 wherein the filler comprises tungsten, barium sulfate, titanium or zinc oxide.

9. The golf ball of claim 7 wherein the core comprises the thermoplastic composition.

10. The golf ball of claim 7 comprising the optional intermediate layer, said optional intermediate layer comprising the thermoplastic composition.

11. The golf ball of claim 1 wherein the core comprises the thermoplastic composition.

12. The golf ball of claim 1 comprising the optional intermediate layer, said optional intermediate layer comprising the thermoplastic composition.

13. A thermoplastic composition comprising or prepared from:

(a) at least one aliphatic, monofunctional organic acid having 4 to 36 carbon atoms, optionally substituted with from one to three substituents independently selected from C 1 to C 8 alkyl groups;

(b) an ethylene acid copolymer consisting essentially of copolymerized comonomers of ethylene and from 19 to 21 weight % of copolymerized comonomers of at least one C 3 to C 8 α,β ethylenically unsaturated carboxylic acid, based on the total weight of the ethylene acid copolymer, having a melt index from about 200 to about 600 g/10 minutes measured according to ASTM D1238 at 190° C. using a 2160 g weight;

wherein the combined acid moieties of (a) and (b) are nominally neutralized to a level from about 120% to about 200%; and optionally

(c) filler.

14. The composition of claim 13 wherein the neutralized organic acid is present in from about 35 to about 45 weight % of the total composition.

15. The composition of claim 13 wherein the organic acid comprises a linear, unsaturated organic acid having from 16 to 24 carbon atoms.

16. The composition of claim 13 wherein the organic acid comprises oleic acid.

17. The composition of claim 13 wherein the C 3 to C 8 α,β ethylenically unsaturated carboxylic acid is acrylic acid or methacrylic acid or a combination thereof.

18. The composition of claim 13 having a PGA compression greater than 100 and a coefficient of restitution that is measured by forming a sphere of 1.50 to 1.68 inches in diameter and firing the sphere at an initial velocity of 125 feet/second against a steel plate positioned 3 feet from the point where initial velocity is determined and dividing the velocity of rebound from the plate by the initial velocity;

wherein the coefficient of restitution is equal to or greater than 0.860 when the composition does not comprise filler; and

wherein the coefficient of restitution is equal to or greater than 0.830 when the composition comprises filler.

19. The composition of claim 18 wherein the composition does not comprise filler and the coefficient of restitution is equal to or greater than 0.870.

20. The composition of claim 13 wherein the filler comprises tungsten, barium sulfate, titanium or zinc oxide.

21. An article comprising the composition of claim 13 , wherein the composition is foamed by the addition of at least one physical or chemical blowing or foaming agent or by blending with polymeric, ceramic, metal, and glass microspheres.

22. The article of claim 21 that is a golf ball or other ball comprising a core or center prepared from the composition.