Golf ball compositions formed of grafted metallocene-catalyzed polymer blends

• US 6,414,082 B1
• Filed: 06/15/2000
• Issued: 07/02/2002
• Est. Priority Date: 01/24/1995
• Status: Expired due to Fees

• Current Assignee: Acushnet Company (FILA Holdings Corp.)
• Original Assignee: Acushnet Company (FILA Holdings Corp.)
• Inventors: Rajagopalan, Murali, Harris, Kevin M.
• Primary Examiner(s): Buttner, David J.
• Application Number:
  US09/594,031
• Time in Patent Office: 747 Days
• Field of Search: 525/72, 525/74, 525/78, 473/354, 473/357, 473/365, 473/372, 473/373, 473/374, 473/377, 473/378, 473/385
• US Class Current: 525/74
• CPC Class Codes: A63B 37/0003 Golf balls
• CPC Class Codes: A63B 37/003 Coefficient of restitution
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0034 Deflection or compression
• CPC Class Codes: A63B 37/0035 Density; Specific gravity
• CPC Class Codes: A63B 37/0037 Flexural modulus; Bending stiffness
• CPC Class Codes: A63B 37/0074 Two piece balls, i.e. cover and core
• CPC Class Codes: A63B 37/0075 Three piece balls, i.e. cover, intermediate layer and core
• CPC Class Codes: A63B 37/04 Rigid cores
• CPC Class Codes: A63B 37/12 Special coverings , i.e. outer layer material balls with finger holes A63B37/0001, golf ball covers A63B37/0023
• CPC Class Codes: C08F 222/06 Maleic anhydride
• CPC Class Codes: C08F 255/00 Macromolecular compounds obtained by polymerising monomers on to polymers of hydrocarbons as defined in group C08F10/00
• CPC Class Codes: C08F 8/00 Chemical modification by after-treatment graft polymers, block polymers, crosslinking with unsaturated monomers or with polymers C08F251/00 - C08F299/00; of conjugated diene rubbers C08C
• CPC Class Codes: C08L 23/08 Copolymers of ethene C08L23/16 takes precedence
• CPC Class Codes: C08L 23/0815 Copolymers of ethene with aliphatic 1-olefins
• CPC Class Codes: C08L 23/0876 Neutralised polymers, i.e. ionomers
• CPC Class Codes: C08L 23/10 Homopolymers or copolymers of propene
• CPC Class Codes: C08L 23/26 modified by chemical after-treatment
• CPC Class Codes: C08L 2314/06 Metallocene or single site catalysts
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/04 : Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 51/06 : grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond
• CPC Class Codes: H04B 1/005 : adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
• CPC Class Codes: H04B 1/006 : using switches for selecting the desired band H04B1/0057 takes precedence

Abstract

The disclosed invention provides a golf ball comprising a core and a cover, wherein at least one of the cover or the core is formed from a polymer blend comprising at least one grafted metallocene-catalyzed polymer, at least one ionomer, and at least one non-ionomer having improved melt flow characteristics.

Claims

1. A golf ball comprising a core and a cover, wherein at least one of the cover or the core is formed from a polymer blend comprising at least one grafted metallocene-catalyzed polymer, at least one ionomer, and at least one non-ionomer.

2. The golf ball of claim 1, wherein the golf ball comprises a cover having at least one of a dimple coverage of greater than about 60 percent, a hardness from about 35 to 80 Shore D, or a flexural modulus of greater than about 500 psi, and wherein the golf ball has at least one of a compression from about 50 to 120 or a coefficient of restitution of greater than about 0.7.

3. The golf ball of claim 1, wherein the grafted metallocene-catalyzed polymer has a flexural modulus of from about 500 psi to about 100,000 psi, the ionomer has a flexural modulus of from about 1,000 psi to about 200,000 psi, and the non-ionomer has a flexural modulus of from about 500 psi to about 100,000 psi.

4. The golf ball of claim 1, wherein the cover comprises the polymer blend.

5. The golf ball of claim 4, wherein the cover layer has a Shore D hardness of less than about 75.

6. The golf ball of claim 4, wherein the cover layer has a thickness from about 0.015 to about 0.125 in.

7. The golf ball of claim 1, wherein the grafted metallocene-catalyzed polymer has been functionalized by grafting an ethylenically-unsaturated monomer onto the at least one metallocene-catalyzed polymer using a post-polymerization reaction.

8. The golf ball of claim 7, wherein the ethylenically-unsaturated monomer is an olefinic monomer having a functional group selected from the group consisting of sulfonic acid, sulfonic acid derivatives, chlorosulfonic acid, vinyl ethers, vinyl esters, primary amines, secondary amines, tertiary amines, mono-carboxylic acids, dicarboxylic acids, partially or fully ester derivatized mono-carboxylic acids, partially or fully ester derivatized dicarboxylic acids, anhydrides of dicarboxylic acids, cyclic imides of dicarboxylic acids, ionomeric derivatives thereof, and combinations thereof.

9. The golf ball of claim 8, wherein the ethylenically-unsaturated monomer comprises maleic anhydride.

10. The golf ball of claim 1, wherein the at least one grafted metallocene-catalyzed polymer is present in an amount from about 5 to about 50 phr.

11. The golf ball of claim 10, wherein the at least one grafted metallocene-catalyzed polymer is present in an amount from about 5 to about 30 phr.

12. The golf ball of claim 1, wherein the at least one ionomer is present in an amount from about 95 to about 50 phr.

13. The golf ball of claim 12, wherein the at least one ionomer is present in an amount from about 95 to about 70 phr.

14. The golf ball of claim 1, wherein the at least one non-ionomer is present in an amount from about 1 to about 25 phr.

15. The golf ball of claim 14, wherein the at least one non-ionomer is present in an amount from about 5 to about 20 phr.

16. The golf ball according to claim 1, wherein the core comprises the polymer blend.

17. The golf ball of claim 1, wherein the core comprises a center and at least one mantle layer disposed between the center and the cover.

18. The golf ball of claim 17, wherein the at least one mantle layer comprises the polymer blend and the cover comprises a thermoset or thermoplastic material.

19. The golf ball of claim 18, wherein the cover comprises the polymer blend and a thermoplastic material.

20. The golf ball of claim 18, wherein the thermoplastic material comprises at least one ionomer.

21. The golf ball of claim 18, wherein the thermoset material comprises polyureas, polyurethanes, and mixtures thereof.

22. The golf ball of claim 18, wherein at least one of the core, cover, or mantle layer comprises a density-adjusting filler.

23. The golf ball of claim 22, wherein the density-adjusting filler comprises zinc oxide, barium sulfate, silica, calcium carbonate, zinc carbonate, tungsten, titanium, and mixtures thereof.

24. The golf ball of claim 17, wherein the at least one mantle layer comprises the polymer blend.

25. The golf ball of claim 17, wherein the center is fluid-filled.

26. The golf ball of claim 17, wherein the center is a solid or hollow center.

27. The golf ball of claim 17, wherein the at least one mantle layer comprises a tensioned elastomeric thread disposed about a fluid-filled center or a solid center.

28. The golf ball of claim 1, wherein the grafted metallocene-catalyzed polymer is formed by grafting an ethylenically-unsaturated monomer onto a metallocene-catalyzed polymer selected from the group consisting of polyethylene and copolymers of ethylene with propylene, butene, pentene, hexene, heptene, octene, and norbomene.

29. The golf ball of claim 28, wherein the grafted metallocene-catalyzed polymer is formed by grafting an ethylenically-unsaturated monomer onto a metallocene-catalyzed polymer selected from the group consisting of polyethylene and copolymers of ethylene with butene.

30. The golf ball of claim 1, wherein the grafted metallocene-catalyzed polymer is formed by grafting an ethylenically-unsaturated monomer onto a metallocene-catalyzed polymer of the formula:

wherein R₁ is hydrogen;

R₂ is hydrogen or lower alkyl selected from the group consisting of CH₃, C₂H₅, C₃H₇, C₄H₉, and C₅H₁₁;

R₃ is hydrogen or lower alkyl selected from the group consisting CH₃, C₂H₅, C₃H₇, C₄H₉, and C₅H₁₁;

R4 is selected from the group consisting of H, CH₃, C₂H₅, C₃H₇, C₄H₉, C₅H_{11, C6}H₁₃, C₇H₁₅, C₈H₁₇, C₉H₁₉, C₁₀H₂₁, and phenyl, in which from 1 to 5 H and R₄ can be replaced by substituents selected from the group consisting of COOH, SO₃H, NH₂, F, Cl, Br, I, OH, SH, silicone, lower alkyl esters and lower alkyl ethers, with the proviso that R₃ and R₄ can be combined to form a bicyclic ring;

R₅ is hydrogen, lower alkyl including C₁-C₅, carbocyclic, aromatic or heterocyclic;

R₆ is hydrogen, lower alkyl including C₁-C₅, carbocyclic, aromatic or heterocyclic; and

wherein x ranges from 99 to 50 weight percent of the polymer, y ranges from 1 to 50 weight percent of the polymer and z ranges from 0 to 49 weight percent of the polymer.

31. The golf ball of claim 1, wherein the polymer blend has a foamed structure.

32. The golf ball of claim 1, wherein the non-ionomeric polymer has the chemical structure:

wherein x=50 to 99 weight %;

y=1 to 50 weight %;

z 0 to 49 weight %;

R₁ H or CH₃;

R₂=methyl, ethyl, propyl, butyl, pentyl, hexyl, hectyl, octyl, or isobornyl; and

n=0 to 12.

33. The golf ball of claim 32, wherein the non-ionomer comprises an olefinic homopolymer, an olefinic copolymer, an olefinic terpolymer, and mixtures thereof.

34. The golf ball of claim 33, wherein the non-ionomer is an acid-containing ethylene copolymer comprising ethylene/methacrylic acid, ethylene/acrylic acid, and mixtures thereof.

35. The golf ball of claim 33, wherein the non-ionomer is an acid-containing ethylene terpolymer comprising ethylene/acrylic acid/n- or isobutyl acrylate, ethylene/methacrylic acid/n- or iso-butyl acrylate, ethylene/acrylic acid/methyl acrylate, ethylene/methacrylic acid/methyl acrylate, ethylene/acrylic acid/iso-bornyl acrylate or methacrylate, ethylene/methacrylic acid/isobornyl acrylate or methacrylate, and mixtures thereof.

36. The golf ball of claim 1, wherein the non-ionomer is present in an amount from about 1 phr to about 25 phr of the total polymer.

37. The golf ball of claim 1, wherein the polymer blend further comprises a non-grafted metallocene catalyzed copolymer.

38. The golf ball of claim 37, wherein the non-grafted metallocene catalyzed copolymer comprises polyolefin plastomers, polyolefin elastomers, or a mixture thereof.

39. A golf ball comprising a core having a center, a cover, and at least one mantle layer disposed between the core and the cover, wherein at least one of the cover, the center, and the at least one mantle layer is formed from a polymer blend comprising from about 5 to about 50 phr of at least one grafted metallocene-catalyzed polymer, from about 95 to about 50 phr of at least one ionomer, and from about 1 to about 25 phr of at least one non-ionomer.

40. A golf ball comprising a core having a center, a cover, and at least one mantle layer disposed between the core and the cover, wherein at least one of the cover, the center, and the at least one mantle layer is formed from a polymer blend comprising:

from about 5 to about 50 phr of at least one grafted metallocene-catalyzed polymer formed by grafting an ethylenically-unsaturated monomer onto a metallocene-catalyzed polymer selected from the group consisting of polyethylene and copolymers of ethylene and butene;

from about 95 to about 50 phr of at least two ionomers, each comprising an ethylene methacrylic/acrylic acid copolymer, wherein at least one ionomer is partially neutralized with lithium and at least one ionomer is partially neutralized with sodium; and

from about 1 to about 25 phr of at least one non-ionomer of the chemical structure;

wherein x=50 to 99 weight %;

y=1 to 50 weight %;

z=0 to 49 weight %;

R₁=H or CH₃;

R₂=methyl, ethyl, propyl, butyl, pentyl, hexyl, hectyl, octyl, or isobornyl; and

n=0 to 12.