JP2007130473A - Highly neutralized acid polymer compositions having low moisture vapor transmission rate and their use in golf balls - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer composition containing a highly neutralized acid polymer having improved moisture vapor transmission rate and a golf ball containing the polymer composition. <P>SOLUTION: The polymer composition has at least 30 wt.% of an ethylene-acrylic acid (methacrylic acid) copolymer to the total polymer weight of the polymer composition. At least 90% of the acid groups of an acid polymer is neutralized. The moisture vapor transmission rate of the polymer composition is 8 g-mil/100in<SP>2</SP>/day or less. The polymer composition is used for an arbitrary one or two or more layers of a core layer, a cover layer or an intermediate layer of a one piece, two-piece, multi-layer and wound golf balls. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention is directed to a polymer composition comprising a highly neutralized acid polymer with a water vapor transmission rate of 8 g-mil / 100 in ² / day or less. The present invention is directed to the use of such a composition for a golf ball.

  Conventional golf balls can be divided into two general classes: solids and spools. Solid golf balls include one-piece, two-piece (ie, solid core and cover), and multilayer (ie, one or more layers of solid core and / or one or more layers of cover) golf balls. A wound golf ball typically includes a solid, hollow, or liquid-filled center surrounded by a stretched elastic material and a cover.

  Golf ball core and cover layers are typically comprised of a polymer composition, which includes, for example, polybutadiene rubber, polyurethane, polyamide, ionomer, and blends thereof. Ionomers, particularly highly neutralized ionomers, are a preferred group of polymers for golf ball layers due to their toughness, durability and a wide range of hardness values. However, conventional highly neutralized ionomers are hydrophilic due to the highly hydrophilic nature of the cation sources traditionally employed for ionomer neutralization, such as magnesium or magnesium salts of fatty acids. As a result of its hydrophilicity, conventional highly neutralized ionomers absorb significant amounts of moisture, for example, 2000 to 10,000 PPM (parts per million), so that manufacturing issues such as parts during injection molding processes The problem is that bubbles are generated, and the performance of the golf ball is deteriorated, for example, the ion agglomeration is plasticized by water molecules and the coefficient of restitution (COR) and rigidity are reduced. Degraded performance.

  Accordingly, there remains a need for compositions comprising highly neutralized acid polymers that have improved water vapor transmission rates. The present invention describes such compositions and their use in golf ball core and cover layers.

In one embodiment, the present invention is directed to a golf ball having at least one layer made from a polymer composition having a water vapor transmission rate of 8 g-mil / 100 in ² / day or less. The polymer composition has a highly neutralized acid polymer.

In another embodiment, the present invention is directed to a golf ball having at least one layer made from a polymer composition having a water vapor transmission rate of 5 g-mil / 100 in ² / day or less. The polymer composition has at least 30% by weight ethylene / acrylic acid (methacrylic acid) copolymer, based on the total polymer weight of the polymer composition. At least 90% of the acid groups of the acid polymer are neutralized.

Detailed Description of the Invention

The golf balls of the present invention include one-piece, two-piece, multilayer and wound golf balls, which have various core structures, intermediate layers, covers and coatings. A golf ball core may be the only single layer with the entire core from the center to the outer perimeter, and may have a center and at least one outer cover layer surrounding it. The innermost part of the center and core is preferably solid, but may be hollow, liquid filled, gel filled or gas filled. The outer core layer may be a solid or a wound layer made from a stretched elastic material. Golf ball covers may include a double cover with one or more layers, eg, an inner and outer cover layer. Optionally, additional layers may be placed between the core and the cover. In the golf ball of the present invention, at least one layer is produced from a polymer composition comprising a water vapor transmission rate of 8 g-mil / 100 in ² / day or less and a highly neutralized acid polymer (“HNP”). Is done. In a preferred embodiment, the polymer composition of this invention is present in the outer core layer of a multilayer golf ball.

As used herein, a “highly neutralized acid polymer” is at least 70% acid, preferably at least 80%, more preferably at least 90%, more preferably at least 95%, more preferably 100% acid. Refers to the acid polymer after the group has been neutralized. According to this invention, an acid polymer or a partially neutralized acid polymer uses a cation source that is less hydrophilic than the magnesium-based cation source traditionally used to produce HNP. When neutralized to more than 70%, the resulting HNP of the present invention has been found to achieve a composition with improved water vapor transmission. For example, when HNP is produced using a cation source having low hydrophilicity, the water vapor permeability of the polymer composition having HNP is 8 g-mil / 100 in ² / day or less, or 5 g-mil / 100 in ² / day or less, Or it is 3 g-mil / 100 in ² / day or less, or 2 g-mil / 100 in ² / day or less, 1 g-mil / 100 in ² / day or less, or less than 1 g-mil / 100 in ² / day. As used herein, water vapor transmission rate (MVTR) is given in g-mil / 100 in ² / day, measured at 20 ° C. and complies with ASTM F1249-99.

“Less hydrophilic” is used herein to mean that the cation source is less hydrophilic than a normal magnesium-based cation source. The HNPs of this invention are made using one or more cation sources that are less hydrophilic. Examples of suitable cation sources that are less hydrophilic include, but are not limited to, silicones, silanes, silicic acid derivatives, and complex ligands; rare earth metal ions and compounds; and alkali metals, alkaline earth metals, and Metal ions and compounds with less hydrophilic transition metals; and combinations thereof. Specific cation sources that are less hydrophilic include, but are not limited to, potassium, cesium, calcium, barium, manganese, copper, zinc, tin, and rare earth metal metal ions and compounds. Potassium-based compounds are preferred cation sources with less hydrophilicity, especially E.I. I. Oxane (TM), commercially available from DuPont, is preferred. Oxane is a monopersulfate, where potassium monopersulfate is a compound of the chemical formula 2KHSO ₅ · KHSO ₄ · K ₂ SO ₄ [potassium hydrogen peroxymonosulfate sulfate (5: 3: 2: 2)]. An active ingredient present as a salt element. The amount of less hydrophilic cation source can be readily determined based on the desired level of neutralization.

The highly neutralized acid polymers of this invention are α, β-ethylene based unsaturated mono- or dicarboxylic acid homopolymer and copolymer salts, and combinations thereof. The term “copolymer” as used herein includes a polymer comprising two types of monomers, a polymer comprising three types of monomers, and a polymer comprising four or more types of monomers. Preferred α, β-ethylenically unsaturated monocarboxylic or dicarboxylic acids are (meth) acrylic acid, ethacrylic acid, maleic acid, crotonic acid, fumaric acid, itaconic acid. (Meth) acrylic acid is particularly preferred. As used herein, “(meth) acrylic acid” means methacrylic acid and / or acrylic acid. Similarly, “(meth) acrylate” means methacrylate and / or acrylate. Preferred acid polymers are C ₃ to C ₈ α, β-ethylenically unsaturated mono- or dicarboxylic acids and ethylene or C ₃ to C ₆ α-olefins, optionally including a softening monomer. A particularly preferred acid polymer is a copolymer of ethylene and (meth) acrylic acid.

When softening monomers are included, such copolymers are referred to as E / X / Y type copolymers, where E is ethylene and X is a C ₃ to C ₈ α, β-ethylenically unsaturated mono Carboxylic acid or dicarboxylic acid, Y is a softening monomer. The softening monomer is typically an alkyl (meth) acrylate, where the alkyl group contains 1 to 8 carbon atoms. Preferred E / X / Y type copolymers are those where X is (meth) acrylic acid and / or Y is (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, methyl (meth) acrylate, and ethyl It is a copolymer that is (meth) acrylate. More preferred E / X / Y type copolymers are ethylene / (meth) acrylic acid / n-butyl acrylate, ethylene / (meth) acrylic acid / methyl acrylate, and ethylene / (meth) acrylic acid / ethyl acrylate.

The amount of ethylene or C ₃ to C ₆ α-olefin in the acid copolymer is typically at least 15 wt%, preferably at least 25 wt%, more preferably at least 40 wt%, based on the total weight of the copolymer, More preferably, it is 60 wt%. The amount of C ₃ to C ₈ α, β-ethylenically unsaturated mono- or dicarboxylic acid in the acid copolymer is typically from 1 wt% to 35 wt%, based on the total weight of the copolymer, It is preferably 4 wt% to 35 wt%, more preferably 6 wt% to 35 wt%, and even more preferably 8 wt% to 20 wt%. The amount of optional softening comonomer in the acid copolymer is typically 0 wt% to 50 wt%, based on the total weight of the copolymer.

  Suitable acid polymers also include partially neutralized acid polymers. Examples of suitable partially neutralized acid polymers include, but are not limited to: I. Includes Surlyn ™ ionomers commercially available from DuPont; AClyn ™ ionomers commercially available from Honeywell International; and Iotek ™ ionomers commercially available from Exxon Mobile Chemical. Additional suitable acid polymers are described, for example, in US Pat. No. 6,953,820 and US Patent Application Publication 2005/0049367, the contents of which applications are incorporated herein by reference.

  The acid polymer of this invention may be a direct copolymer in which all monomers are added simultaneously to polymerize the polymer, which is described, for example, in US Pat. No. 4,351,931, the contents of which are incorporated herein by reference. Ionomers can be made from direct copolymers as described in US Pat. No. 3,264,272, the contents of which are hereby incorporated by reference. Alternatively, the acid polymer of this invention may be a graft copolymer in which monomers are grafted onto an existing polymer, as described, for example, in US Patent Application Publication 2002/0013413, the contents of which are referred to. Here.

  The composition of this invention comprises at least one HNP according to the invention (ie, produced using a less hydrophilic cation source) and optionally one or more additional HNPs. If additional HNP is included, the additional HNP is one or more HNPs according to the invention and / or one or more normal HNPs (ie produced using a normal cation source) Good. The total amount of HNP in the composition is preferably at least 30 wt%, more preferably at least 50 wt%, and preferably 50 wt% to 99.5 wt%, more preferably 60 wt%, based on the total weight of the polymer of the composition. % To 98 wt%. Preferably the amount of HNP according to the invention is at least 30 wt% in the composition.

  In order to be processable, the HNP-containing composition of the present invention has a melt flow index of at least 0.5 g / 10 min. Preferably, the melt flow index of the HNP-containing composition is 0.5 g / 10 min to 10.0 g / 10 min, more preferably 1.0 g / 10 min to 5.0 g / 10 min, still more preferably 1.0 g. / 10 minutes to 4.0 g / 10 minutes.

  The HNP-containing composition of the present invention may optionally include one or more melt flow modifiers. Suitable melt flow modifiers include organic acids and salts thereof, polyamides, polyesters, polyacrylates, polyurethanes, polyethers, thermoplastic polyureas, polyhydric alcohols, and combinations thereof. Suitable organic acids are aliphatic organic acids, aromatic organic acids, saturated monofunctional organic acids, unsaturated monofunctional organic acids, multiunsaturated monofunctional organic acids, and dimer derivatives thereof. Specific examples of suitable organic acids include, but are not limited to, caproic acid, caprylic acid, capric acid, lauric acid, stearic acid, behenic acid, erucic acid, oleic acid, linoleic acid, myristic acid, benzoic acid, Including palmitic acid, phenylacetic acid, naphthalenic acid, and dimer derivatives thereof. When the composition of this invention includes one or more organic acid salts, the cation source used to produce the organic acid salt is preferably a cation source with less hydrophilicity. Suitable organic acids are described in more detail, for example, in US Pat. No. 6,756,436, the contents of which are hereby incorporated by reference.

  Additional non-fatty acid melt flow modifiers suitable for use in the compositions of this invention include those described in US patent applications 11/216725 and 11/216726, the disclosure of which is incorporated herein by reference. Incorporate here.

The HNP-containing composition of the invention may include one or more additives in an amount of 0 wt% to 60 wt%, based on the total weight of the composition. Suitable additives include, but are not limited to, chemical expansion and foaming agents, optical brighteners, colorants, fluorescent agents, whitening agents, UV absorbers, light stabilizers, antifoaming agents, processing aids, Mica, talc, nanofillers, antioxidants, stabilizers, softeners, perfume ingredients, plasticizers, impact modifiers, TiO ₂ , acid copolymer waxes, surfactants, and fillers such as zinc oxide, tin oxide, Includes barium sulfate, zinc sulfate, calcium oxide, calcium carbonate, zinc carbonate, barium carbonate, clay, tungsten, tungsten carbide, silica, zinc silicate, reground (recycled material), and mixtures thereof. Suitable additives are fully described, for example, in US Patent Application Publication 2003/0225197, incorporated herein by reference.

The composition can optionally be prepared by blending the HNP of the present invention with one or more additional polymers, such as thermoplastic polymers and elastomers. Examples of thermoplastic polymers suitable for blending with the HNP of this invention include, but are not limited to, polyolefins, polyamides, polyesters, polyethers, polycarbonates, polysulfones, polyacetals, polylactones, acrylonitrile-butadiene-styrene resins, polyphenylene oxides. , Polyphenylene sulfide, styrene-acrylonitrile resin, styrene maleic anhydride, polyimide, aromatic polyketone, ionomer and ionomer precursor, acid copolymer, conventional HNP, polyurethane, grafted or ungrafted metallocene catalyst polymer, single site catalyst polymerization Polymers, highly crystalline acid polymers, cationic ionomers, and combinations thereof. Specific polyolefins suitable for blending one or more linear or branched or cyclic _C 2 _{-C 40} olefin, specifically, of one or more _C 2 _{-C 40 olefins,} the C 3 _{-C 20} It is a polymer containing ethylene or propylene copolymerized with an α-olefin or a C ₃ -C ₁₀ α-olefin. Specific conventional HNPs suitable for blending include, but are not limited to, one or more HNPs disclosed in US Pat. Nos. 6,756,436, 6,894,098, and 6,953,820, the disclosure of which Are incorporated herein by reference. Examples of elastomers suitable for blending with the polymers of this invention include, but are not limited to, all natural and synthetic rubbers, ethylene propylene rubber ("EPR"), ethylene propylene diene rubber ("EPDM"), Styrene block copolymer rubber (eg, SI, SIS, SB, SBS, SIBS, etc., “S” is styrene, “I” is isobutylene, “B” is butadiene), butyl rubber, halobutyl rubber, isobutylene and para-alkyl Copolymers of styrene, halogenated copolymers of isobutylene and para-alkylstyrene, natural rubber, polyisoprene, copolymers of butadiene with acrylonitrile, polychloroprene, alkyl acrylate rubber, isoprene chloride rubber, acrylonitrile isoprene chloride Beam, and a polybutadiene rubber (cis and trans). Still other suitable blend polymers include those disclosed in US Pat. No. 5,981,658, eg, column 14, lines 30-56, the contents of which are incorporated herein by reference. The blends described herein can be made by combining the reactor in series with the reactor blend by blending after the reactor, and by producing multiple types of polymers using multiple catalysts in the same reactor, Can be manufactured. The polymer may be mixed before entering the extruder or may be mixed in the extruder.

  The flexural modulus of the composition of this invention is typically from 3000 psi to 200000 psi, preferably from 5000 psi to 150,000 psi, more preferably from 10,000 psi to 125000 psi, and even more preferably from 10,000 psi to 100,000 psi. The material hardness of the composition is generally from 30 Shore D to 80 Shore D. In embodiments where the composition is in the center of a golf ball, the material hardness is preferably 30 Shore D to 50 Shore D. In embodiments where the composition is in a golf ball cover layer, outer core layer or intermediate layer between the core and cover, the material hardness is preferably 30 Shore D to 70 Shore D. The notched Izod impact strength of the compositions of this invention is generally at least 2 ft · lb / in measured at 23 ° C. according to ASTM D256.

  The present invention is not limited to a specific method or apparatus for producing the composition. In the preferred embodiment, it is prepared by the following process. An acid polymer, preferably ethylene / (meth) acrylic acid, is fed to a melt extruder, such as a single or twin screw extruder. An appropriate amount of a less hydrophilic cation source is added to the molten acid polymer. The acid polymer may be partially neutralized prior to contact with a cation source, preferably a cation source selected from calcium, magnesium and zinc metal salts and compounds. The acid polymer / cation mixture is intensively mixed before it is extruded as a strand from the mold head. Optionally, a less hydrophilic cation source based on a fatty acid salt or non-fatty acid salt flow modifier is introduced during HNP generation. In a specific aspect of this invention, the ethylene / (meth) acrylic acid copolymer is prepared from E.I. I. Nuclel ™ acid copolymers commercially available from DuPont (eg, Nuclel 960. Ethylene / methacrylic acid copolymer) and Primacor ™ polymers (eg, Primacor XUS 60758.08L and XUS 60751) commercially available from Dow Chemical. 18. Ethylene / acrylic acid copolymer containing 13.5% and 15.0% acid respectively).

  The composition of the present invention can be used for various applications. For example, HMP-containing compositions are suitable for use in golf equipment. Golf equipment includes, but is not limited to, golf balls, golf shoes, and golf clubs.

  The golf ball of the present invention may be a spool, a one-piece, a two-piece, or a multi-layer golf ball. However, at least one layer is made from a composition containing HNP made from a smaller hydrophilic cation source. In the golf ball having two or more layers having the HNP of the present invention, the HNP according to the invention of one layer may be the same as or different from the HNP according to the invention of another layer. The layer having HNP according to the present invention may be any one or more of a core layer (eg, center or outer core layer), an intermediate layer, or a cover layer. The compositions of this invention may be foamed or filled with a density adjusting material to achieve the desired golf ball performance characteristics.

  The present invention is not limited to a specific method for producing a golf ball layer. Note that the layer may be manufactured by any suitable technique including injection molding, compression molding, molding, and reactive injection molding.

  In a preferred embodiment of the present invention, the invention comprises a compression molded core, at least one intermediate layer injection molded or compression molded comprising HNP made using a less hydrophilic cation source, and polyurethane Alternatively, a multilayer ball having a polyurea outer cover layer is realized. The outer cover layer of polyurethane or polyurea may be thermoset or thermoplastic. The thermoplastic material can be formed as a golf ball layer by conventional molding or reactive injection molding techniques. The thermoplastic material can be formed as a golf ball layer by conventional compression or injection molding techniques. Light stable polyureas and polyurethanes are preferred as the outer cover layer. Preferably, the rubber core composition has a base rubber, a crosslinking agent, a filler, and a co-crosslinking agent or a Philly radical initiator and optionally a cis-trans conversion catalyst. Typical rubber materials are natural and synthetic rubbers, including but not limited to polybutadiene and styrene butadiene. The cross-linking agent typically comprises a metal salt, such as an acid having 3 to 8 carbon atoms, such as a zinc or magnesium salt of (meth) acrylic acid. The free radical initiator may be any known polymerization initiator that decomposes in the cure cycle, including but not limited to dicumyl peroxide, 1,1-di- (t-butylperoxy) 3, 3, 5 -Trimethylcyclohexane, a-a bis-(-butylperoxy) diisopropylbenzene, 2,5-memethyl-2,5 di- (t-butylperoxy) hexane or di-t-butylperoxide, and mixtures thereof. Suitable types and amounts of rubbers, crosslinkers, fillers, cocrosslinkers and initiators are fully described, for example, in US Patent Application Publication No. 2003/0144087, the contents of which are hereby incorporated by reference. See also US Patent Application Publication No. 2003/0144087 for various ball structures and materials that can be used for golf balls.

In another preferred embodiment, the present invention provides a multilayer golf ball comprising a solid core, an outer core layer, and a cover. Here, the outer core layer is manufactured from a composition containing HNP manufactured using a cation source having a lower hydrophilicity. In a specific aspect of the present invention, the water vapor permeability of the composition is 8 g-mil / 100 in ² / day or less, thereby suppressing moisture from entering the core. In another specific aspect of this example, the HNP is preferably based on an ethylene / (meth) acrylic acid copolymer, preferably not so, but may also contain a softening comonomer. The solid core can be made from any suitable core material, preferably polybutadiene, polyisoprene, ethylene propylene rubber (“EPR”), ethylene propylene diene rubber (“EPDM”), styrene block copolymer rubber (eg, SI, SIS, SB, SBS, SIBS, etc., “S” is styrene, “I” is isobutylene, “B” is butadiene), butyl rubber, halobutyl rubber, copolymer of isobutylene and para-alkylstyrene, isobutylene and para-alkylstyrene Manufactured from conventional rubbers selected from halogenated copolymers, natural rubber, copolymers of butadiene with acrylonitrile, polychloroprene, alkyl acrylate rubber, isoprene chloride rubber, and acrylonitrile chloride isoprene rubber It is. The core diameter is preferably 1.40 inches to 1.55 inches. The cover is a robust and cut resistant material selected from conventional golf ball cover materials based on the desired performance characteristics. The cover may have one or more layers, and preferably has an overall thickness of 0.020 inches to 0.045 inches. Suitable cover materials are ionomer resins, blends of ionomer resins, thermoplastic and thermoset urethanes, thermoplastic and thermoset ureas, (meth) acrylic acid, thermoplastic rubber polymers, polyurethanes, and synthetic or natural vulcanizates, For example, balata is included. Other suitable core and cover materials are disclosed, for example, in US Patent Application Publication No. 2005/0164810, US Pat. No. 5,919,100, and PCT Publications WO 00/23519 and WO 00/29129, the contents of which are hereby incorporated by reference. Incorporate

  In another preferred embodiment, the present invention provides a two-piece golf ball having a core and a cover. Here, the cover is produced from a composition comprising HNP produced using a less hydrophilic cation source. The material hardness of the cover is preferably 30 Shore D to 70 Shore D. The cover thickness is preferably 0.020 inches to 0.350 inches, more preferably 0.025 inches to 0.090 inches. The core is preferably a solid core made from a suitable core material, preferably polybutadiene, polyisoprene, ethylene propylene rubber ("EPR"), ethylene propylene diene rubber ("EPDM"), styrene block copolymer rubber (e.g. SI, SIS, SB, SBS, SIBS, etc., “S” is styrene, “I” is isobutylene, “B” is butadiene), butyl rubber, halobutyl rubber, copolymer of isobutylene and para-alkylstyrene, isobutylene and A selected from a halogenated copolymer of para-alkyl styrene, natural rubber, a copolymer of butadiene with acrylonitrile, polychloroprene, alkyl acrylate rubber, isoprene chloride rubber, and acrylonitrile isoprene chloride rubber. It is manufactured from rubber. In a preferred aspect of this example, the core is made from the reaction product of rubber, crosslinker, filler, Philly radical initiator, and optional cis-trans conversion catalyst. The core diameter is preferably between 1.00 inch and 1.63 inch. The core Atti compression is preferably less than 100.

  In another preferred embodiment, the present invention realizes a two-piece or multi-layer golf ball comprising a center made from a composition comprising HNP made using a less hydrophilic cation source. The HNP is preferably based on a polymer of the E / X / Y type. Preferably, the material hardness of the core is 30 Shore D to 50 Shore D. The cover is a robust and cut resistant material selected from conventional golf ball cover materials based on the desired performance characteristics. The cover may have one or more layers, and preferably has an overall thickness of 0.020 inches to 0.045 inches. Suitable cover materials include, but are not limited to, ionomer resins, blends of ionomer resins, thermoplastic and thermosetting urethanes, thermoplastic and thermosetting ureas, (meth) acrylic acid, thermoplastic rubber polymers, polyurethanes, and Contains synthetic or natural vulcanized rubber, such as balata.

  The coefficient of restitution (COR) of golf balls of this invention is generally at least 0.790, preferably at least 0.800, more preferably at least 0.805, even more preferably 0.810, and its Atti compression Is from 75 to 110, preferably from 90 to 100. As used herein, “COR” is defined as the ratio of the rebound velocity to the incident velocity when the ball is launched towards a rigid plate. When determining the COR, it is understood that the incident velocity is 125 ft / s.

  When the lower limit of numerical values and the upper limit of numerical values are indicated here, it can be easily understood that these values can be used in any combination.

  All patents, publications, test procedures and other documents cited herein, including priority documents, are hereby incorporated by reference to the extent they do not conflict with the present invention.

  Although exemplary embodiments of the present invention have been specifically described, it should be noted that various other modifications will be apparent to those skilled in the art and may be easily made without departing from the spirit of the invention. Accordingly, the scope of the appended claims is not intended to be limited to the examples and description disclosed herein. The claims should be understood to cover all novel patentable features of the invention, including all features equivalent to those of ordinary skill in the art.

Claims (20)

Comprising at least one layer made from the polymer composition, the water vapor transmission rate (MVTR) of the polymer composition is 8 g-mil / 100 in ² / day or less, and the polymer composition is highly neutralized A golf ball comprising an acid polymer.   The golf ball of claim 1, wherein at least 90% of the acid groups in the highly neutralized acid polymer are neutralized. The golf ball according to claim 1, wherein the polymer composition has an MVTR of 5 g-mil / 100 in ² / day or less. The highly neutralized acid polymer is from 4 wt% to 35 wt% α, β-ethylenically unsaturated carboxylic acid based on the total weight of the copolymer, and from 0 wt% based on the total weight of the copolymer. The golf ball according to claim 1, which is a salt of a copolymer of 50 wt% C ₁ -C ₈ alkyl (meth) acrylate.   The golf ball of claim 1, wherein the highly neutralized acid polymer is a blend of two or more independently selected highly neutralized acid polymers.   The highly neutralized acid polymer comprises neutralizing the acid polymer by contacting one or more acid polymers with a sufficient amount of a less hydrophilic cation source in the presence of a melt flow modifier. The golf ball of claim 1 manufactured by a process comprising increasing the level to at least 70%.   The golf ball according to claim 6, wherein the cation source is selected from metal ions or compounds of alkali metals, alkaline earth metals, and transition metals, or a combination thereof, and the cation source is less hydrophilic than magnesium.   The cation source includes potassium, cesium, calcium, barium, manganese, copper, zinc, and tin metal ions or compounds; silicone, silane, and silicic acid derivatives, and complex ligands; and rare earth metal ions and compounds The golf ball according to claim 6, which is selected.   The polymer composition is in an amount sufficient to neutralize one or more acid polymers with an organic acid or metal salt of an organic acid and at least 70% of all acid functionality present in the polymer composition. The golf ball of claim 1, wherein the golf ball is produced by a process comprising contacting a less hydrophilic cation source.   The golf ball of claim 9, wherein the acid polymer is partially neutralized prior to contact with the less hydrophilic cation source.   The less hydrophilic cation sources include potassium, cesium, calcium, barium, manganese, copper, zinc, and tin metal ions or compounds; silicone, silane, and silicic acid derivatives, and complex ligands; and rare earth elements The golf ball according to claim 9, wherein the golf ball is selected from metal ions and compounds.   The organic acid comprises an aliphatic organic acid, an aromatic organic acid, a saturated monofunctional organic acid, an unsaturated monofunctional organic acid, and a multi-unsaturated monofunctional organic acid, salts thereof, and combinations thereof The golf ball according to claim 9, selected from a group.   The above organic acids are caproic acid, caprylic acid, capric acid, lauric acid, stearic acid, behenic acid, erucic acid, oleic acid, linoleic acid, myristic acid, benzoic acid, palmitic acid, phenylacetic acid, naphthalenic acid, dimers thereof The golf ball of claim 9, selected from the group consisting of derivatives, salts thereof, and combinations thereof.   The golf ball according to claim 9, wherein the metal of the organic acid salt is selected from the group consisting of alkalis, alkaline earths, and transition elements, and the metal ions are less hydrophilic than magnesium ions.   The organic acid salt includes potassium, cesium, calcium, barium, manganese, copper, zinc, and tin metal ions or compounds; silicone, silane, and silicic acid derivatives, and complex ligands; and rare earth metal ions and compounds The golf ball of claim 9, wherein the golf ball is produced using a cation source selected from:   The golf ball has a core and a cover, and the cover is formed from the polymer composition, and the core is a reaction product of rubber, a cross-linking agent, a filler, a free radical initiator, and an optional cis-trans conversion catalyst. The golf ball according to claim 1, formed from:   The core has an Atti compression of 10 to 100, the core has a surface hardness of 20 Shore D to 70 Shore D, the core diameter is 1.00 inches to 1.63 inches, and the cover thickness The golf ball of claim 16, wherein 0.020 to 0.350 inch.   The golf ball has a core and a cover, the core is formed from the polymer composition, and the cover is made of an ionomer resin, a blend of ionomer resins, a highly neutralized polymer, a thermoplastic polyurethane, and a thermosetting polyurethane. The golf ball of claim 1, formed from a material selected from the group consisting of: a thermoplastic polyurea, a thermosetting polyurea, and blends thereof.   The golf ball has a core, a cover, and an intermediate layer disposed between the core and the cover, the intermediate layer is formed from the polymer composition, and the core is rubber, a crosslinking agent, a filler, a free radical initiation The golf ball of claim 1, formed from a reaction product of an agent and an optional cis-trans conversion catalyst. From a polymer composition having a water vapor transmission rate of 5 g-mil / 100 in ² / day or less and having at least 30 wt% ethylene / (meth) acrylic acid copolymer based on the total weight of the polymer composition A golf ball comprising at least one manufactured layer, wherein at least 90% of the acid groups of the polymer composition are neutralized.