GOLF BALLS HAVING LAYERS MADE FROM FUNCTIONALIZED ETHYLENE COPOLYMERS
Golf balls having a core and containing at least one surrounding layer made from a functionalized ethylene copolymer having a linear or substantially linear structure are provided. The core may be made of a polybutadiene rubber material. The functionalized ethylene copolymer composition may be used to form any layer in the golf ball structure such as, for example, an outer core, intermediate layer, inner cover, and/or outer cover. The composition may be blended with ionomeric or non-ionomeric resins such as polyamides, polyurethanes, polyureas, polycarbonates, polyesters, and polyacrylates to form the layer. The resulting layers provide the golf ball with improved resiliency and impact durability.
1 . A golf ball having a core and at least one surrounding layer formed from a composition comprising a functionalized ethylene copolymer, wherein the functionalized ethylene copolymer has a linear or substantially linear structure and is produced by copolymerizing an ethylene monomer with a comonomer having a functional group in the presence of a metal-based catalyst selected from the group consisting of iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium, and platinum.
2 . The golf ball of claim 1 , wherein the core comprises a rubber material.
3 . The golf ball of claim 2 , wherein the rubber material is polybutadiene.
4 . The golf ball of claim 1 , wherein the functional group is 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, and ionomeric derivatives thereof.
5 . The golf ball of claim 4 , wherein the functional group is acrylic or methacrylic acid.
6 . The golf ball of claim 4 , wherein the functional group is an acrylate or methacrylate.
7 . The golf ball of claim 4 , wherein the functional group is selected from the group consisting of maleic anhydride, maleic acid, and maleate ester.
8 . The golf ball of claim 1 , wherein the acrylic or methacrylic acid is neutralized to less than 70% by a cation source.
9 . The golf ball of claim 1 , wherein the acrylic or methacrylic acid is neutralized to greater than 70% by a cation source.
10 . The golf ball of claim 1 , wherein the maleic anhydride, maleic acid, or maleate ester is neutralized to less than 70% by a cation source.
11 . The golf ball of claim 1 , wherein the maleic anhydride, maleic acid, or maleate ester is neutralized to greater than 70% by a cation source.
12 . The golf ball of claim 1 , wherein the functionalized ethylene copolymer further comprises an α-olefin comonomer having 3 to 20 carbon atoms.
13 . The golf ball of claim 12 , wherein the α-olefin comonomer is selected from the group consisting of propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene.
14 . The golf ball of claim 1 , wherein the composition comprising the functionalized ethylene copolymer has a flexural modulus in the range of about 10 to about 100 kpsi.
15 . The golf ball of claim 1 , wherein the composition comprising the functionalized ethylene copolymer has a material hardness in the range of about 25 to about 75 Shore D.
16 . The golf ball of claim 1 , wherein the composition comprising the functionalized ethylene copolymer has an elongation at break of about 100 to about 400%.
17 . The golf ball of claim 1 , wherein the composition comprising the functionalized ethylene copolymer has a tensile strength at break of about 1 to about 7 kpsi.
18 . The golf ball of claim 1 , wherein the metal-based catalyst is a ruthenium-based catalyst having the following structure:
wherein L 1 and L 2 are independently selected from the group consisting of alkyl phosphine, aryl phosphine, 1,3-dimesitylimidazol-2-ylidene, 1,3-di(2,6-diisopropylphenyl)imidazol-2-ylidene, 1,3-diarylimidazol-2-ylidene, 1,3-dimesitylimidazolidin-2-ylidene, 1,3-di(2,6-diisopropylphenyl)imidazolidin-2-ylidene, 1,3-diphenyltriazine, and pyridine; L 3 , if present, is pyridine and is identical to L 2 ; and R 4 is selected from the group consisting of hydrogen, C 1 -C 20 linear alkyl, C 1 -C 20 branched alkyl, C 1 -C 20 cycloalkyl, C 1 -C 20 alkenyl, aryl and phenyl.
19 . The golf ball of claim 1 , wherein the ball comprises an intermediate layer overlying the core and a cover layer overlying the intermediate layer, the intermediate layer being formed from the composition comprising the functionalized ethylene copolymer.
20 . The golf ball of claim 19 , wherein the intermediate layer has a thickness in the range of about 0.010 to about 0.030 inches and a Shore D material hardness in the range of about 50 to about 75.
21 . The golf ball of claim 19 , wherein the cover layer is made of a thermoplastic or thermoset polyurethane, polyurea, or polyurethane/polyurea hybrid composition.
22 . The golf ball of claim 19 , wherein the cover layer is made of an ionomer resin.
23 . The golf ball of claim 1 , wherein the ball further comprises an intermediate layer overlying the core and a cover layer overlying the intermediate layer, the cover layer comprising an inner cover layer and surrounding outer cover layer, the inner cover layer being formed from the composition comprising the functionalized ethylene copolymer.
24 . The golf ball of claim 23 , wherein the inner cover layer has a thickness in the range of about 0.020 to about 0.500 inches and a Shore D material hardness in the range of about 50 to about 70.
25 . The golf ball of claim 23 , wherein the outer cover layer is made of a thermoplastic or thermoset polyurethane, polyurea, or polyurethane/polyurea hybrid composition.
26 . The golf ball of claim 23 , wherein the outer cover layer is made of an ionomer resin.
27 . The golf ball of claim 1 , wherein the ball further comprises an intermediate layer overlying the core and a cover layer overlying the intermediate layer, the cover layer comprising an inner cover layer and surrounding outer cover layer, the intermediate layer being formed from the composition comprising the functionalized ethylene copolymer.
28 . The golf ball of claim 1 , wherein the ball further comprises an intermediate layer overlying the core and a cover layer overlying the intermediate layer, the core having an inner portion and a surrounding outer core layer, the outer core layer being formed from the composition comprising the functionalized ethylene copolymer.