Vibration damping materials, equipment and sporting goods

Abstract

To provide a vibration damping material for sporting goods that dampens or reduces energy such as vibration or sound. A vibration-damping material includes a polymer composition having a butyl rubber polymer and, optionally, a phenol-formaldehyde-based resin. The vibration-damping material can be used in sporting goods requiring shock, vibration, and / or sound reduction and absorption, and can provide cushioning to the user.

Description

[Technical Field]

[0001] This application claims the benefit of and priority to U.S. Provisional Patent Application No. 62 / 877,028, filed July 22, 2019, and U.S. Provisional Patent Application No. 62 / 892,854, filed August 28, 2019, both of which are incorporated herein by reference.

[0002] The present disclosure relates to a damping material for sporting goods that attenuates or reduces energy, such as vibration or sound. The damping material includes a polymer composition having a butyl rubber polymer and, optionally, a phenol-formaldehyde-based resin. The damping material can be used in sporting goods requiring reduction and absorption of shock, vibration, and / or sound, and the damping material can provide cushioning to the user. The present disclosure also relates to sporting goods that include such a damping material. [Background technology]

[0003] Some types of sporting equipment are used to absorb blows, hits, and / or impacts. To protect the user, it is often desirable to attenuate excess energy during use of the sporting equipment. Various materials meet the need for such attenuation and absorption. However, there is an unmet need for materials that improve the attenuation and absorption of impact, vibration, and sound in sporting equipment. Summary of the Invention [Problem to be solved by the invention]

[0004] Thus, there remains a need for sporting goods and devices for sporting goods that mitigate and / or attenuate energy during use of the device. [Means for solving the problem]

[0005] In one aspect, a sporting item includes a body and a vibration damping material associated with the body, the vibration damping material comprising a polymer composition that includes butyl rubber.

[0006] In another aspect, a vibration damping material for a sporting good includes a layer comprised of a polymer composition including butyl rubber, the layer configured to be attached to the sporting good.

[0007] The vibration damping material may be in a form selected from strips, sheets, films, strings, ropes, fibers, chips, rings, shapes, mouldings, slabs, tapes, coatings, perforated sheets, corrugations, beads, foams and laminates. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a front elevation view of a sporting item. [Figure 2] 1 is a perspective view of one embodiment of a damping material according to the present disclosure; FIG. [Figure 3] FIG. 3 is a perspective view illustrating the positioning of the damping material of FIG. 2 on sporting equipment. [Figure 4] FIG. 3 is a perspective view illustrating the positioning of the damping material of FIG. 2 on sporting equipment. [Figure 5] FIG. 3 is a perspective view illustrating the positioning of the damping material of FIG. 2 on sporting equipment. [Figure 6] FIG. 10 is a perspective view of another embodiment of a damping material according to the present disclosure. [Figure 6A] 7 is an enlarged top view of one end of the damping material of FIG. 6. [Figure 7] 7a to 7d are perspective views showing the state in which the damping material of FIG. 6 is applied to the handle of a sporting good. [Figure 8] FIG. 10 is a perspective view of another sporting item. [Figure 9] 9 is a cross-sectional view of the sleeve of the sporting goods shown in FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0009] definition All percentages expressed in this utility application are weight percent of the total weight of the composition unless otherwise expressed.

[0010] All proportions expressed in this application are by weight, ie, by weight, unless otherwise expressed.

[0011] In this application, ranges are used as a shorthand notation to avoid simply listing every value within the range: any suitable value within the range can be selected as the upper, lower, or end point of the range.

[0012] In this application, unless the context clearly indicates otherwise, the singular form of a word includes its plural, and vice versa. Thus, references to "a," "an," and "the" generally include the plural of the respective term they modify. For example, a reference to "method" includes its plural, "method." Similarly, the terms "comprise," "comprises," and "including," whether used as transitional phrases within a utility claim, are to be interpreted inclusively, rather than exclusively. Similarly, the terms "include," "including," and "or" are to be interpreted inclusively, unless such a construction is clearly prohibited by the context. Similarly, the term "example," particularly when followed by a list of terms, is merely exemplary and illustrative and is not to be considered exclusive or comprehensive.

[0013] The methods, compositions, and other advances disclosed herein are not limited to the particular methodology, protocols, and reagents described herein, as these may vary, as will be understood by those of skill in the art. Furthermore, the terminology used herein describes particular embodiments only and is not to be construed as limiting the scope of the disclosure or claimed subject matter.

[0014] Unless otherwise defined, all technical and scientific terms, technical terms, and acronyms used in this application have the meaning commonly understood by one of ordinary skill in the art of the invention or the field in which the term is used. Any compositions, methods, articles of manufacture, or other means or materials similar or equivalent to those described in this application can be used in the practice of the invention. However, specific compositions, methods, articles of manufacture, or other means or materials are described for illustrative purposes only.

[0015] All patents, patent applications, publications, technical and / or scientific articles, and other references cited or referred to in this application are incorporated by reference in their entirety to the extent permitted by law. The discussion of such references is intended merely to summarize the assertions made in those references. No admission is made that such patents, patent applications, publications, or references, or any portion thereof, are relevant, important, or prior art. The right to challenge the accuracy and pertinence of assertions that such patents, patent applications, publications, and other references are relevant, important, or prior art is specifically reserved.

[0016] In some applications, the formulations of the present disclosure exhibit unexpected and surprising improvements over, for example, exemplary polyurethane-based materials currently available for damping purposes. More specifically, the polymer composition formulations exhibit at least about 20% to about 500% improvement in tan delta values, i.e., the ratio of the loss modulus to the storage modulus of the material, during dynamic mechanical analysis of articles made from such formulations, measured at room temperature and at various frequencies.

[0017] In one embodiment, the polymer composition comprises phenol-formaldehyde resin or sulfur-cured butyl rubber, at least one filler, and optionally stearic acid and mineral oil. The components of the uncured formulation are described below. The present disclosure relates to both the uncured and cured formulations described herein. Alternatively, the polymer composition may comprise any suitable polymer that dampens or mitigates energy to reduce vibration and frequency during use.

[0018] With reference to the figures, the present disclosure is directed to a damping material for sporting equipment. The damping material or vibration damping material may attenuate and / or reduce vibrations, sound, and / or other forms of energy generated during use of the sporting equipment. The damping material may be integrated with, attached to, or otherwise associated with the sporting equipment. In this specification, the damping material may be described in connection with particular sporting equipment. However, such description is exemplary. The damping material may be applied to any sporting equipment. Such sporting equipment includes, but is not limited to, rackets (tennis, racquetball, badminton, etc.), paddles (table tennis, pickleball, tennis, platform tennis, etc.), sticks (hockey, lacrosse, etc.), clubs (golf, etc.), bats (baseball, softball, cricket, etc.), hats, gloves (baseball, hockey, golf, etc.), shoes, pads (football, soccer, hockey, lacrosse, shin, knee, shoulder, etc.), helmets and headgear (football, baseball, bicycle, auto racing, hockey, soccer, wrestling, etc.).

[0019] In one embodiment, a sporting goods includes a body and a damping material associated with the body. The damping material includes a polymer composition. In one embodiment, the polymer composition can be a composition including butyl rubber, such as any of the butyl rubber-containing polymer compositions disclosed herein. In alternative embodiments, the polymer composition can be any polymer composition that dampens or attenuates energy to reduce vibration and frequency during use, thereby improving the experience of a user of the sporting goods. For example, the polymer composition can include any suitable polymer. Optionally, the polymer composition can also include other components. In one embodiment, the polymer composition can include a polymer and a metal. For example, the polymer composition can include a polymer and tungsten. In one embodiment, the polymer composition can include a polyether block amide and tungsten. In other embodiments, the polymer composition can include aflas, chlorosulfonated polyethylene, epichlorohydrin, ethylene propylene, fluoroelastomer, fluorosilicone, hydrogenated nitrile, natural rubber, nitrile, perfluoroelastomer, polyacrylic, polychloroprene, polyurethane, silicone, styrene butadiene, foam, plastic, sheet stock, moon gel, aerogel, basalt, and tungsten.

[0020] As mentioned above, the damping material may be integral or one piece with the body and / or attached to the body or otherwise associated with the body. In one embodiment, the body of the sports equipment includes a frame, and the damping material is associated with the frame. In another embodiment, the body includes a shaft, and the damping material is associated with the shaft. If the shaft is hollow, the damping material may be applied to the interior of the shaft via solid or particle insertion or a foam spray-type application. If the frame is hollow, the damping material may be placed inside the hollow frame during the manufacturing process in the form of foam, spray, beads, or strips. Furthermore, the damping material can replace the grommets on a tennis racket. The body may also include a handle, in which case the damping material is associated with the handle.

[0021] The damping material may be part of the body of the sporting goods or may include a layer of polymer composition attached to the body. The layer of polymer composition may be in the form of a strip or a sheet. The strip may be a long, narrow strip that is longer than it is wide. The strip may be pre-cut to a desired size. Alternatively, the strip may be provided in a roll or as a tape, in which case the user may custom-cut the strip to a desired size. In the case of a sheet, the sheet may be configured to cover a size relatively larger than the strip. The sheet may be a regular or irregular shape. For example, the sheet may be square, rectangular, circular, oval, etc., or the sheet may be a custom shape or may be configured to be cut to a custom shape.

[0022] In one embodiment, the damping material may be a strip or tape including a layer of a polymer composition and an adhesive layer for attaching the strip or tape to the body of the sporting goods. Optionally, the strip or tape may include a gripping material to aid a user in gripping the sporting goods. The layer of gripping material may be, for example, genuine or synthetic leather, a polymer layer, or a synthetic polymer layer. The gripping material may have an outer surface intended to be gripped by a user's hand. The outer surface may be textured or sticky to aid in gripping. The gripping material may be attached to the layer of polymer composition by any suitable method, such as adhesive, heat, interlocking, etc. In one embodiment, an adhesive may be present between the layer of gripping material and the layer of polymer composition.

[0023] Optionally, the damping material may comprise multiple strips or sheets, which may be positioned at different locations on the body of the sporting goods.

[0024] Optionally, the damping material may be a sleeve having a bore for receiving a portion of the sporting equipment. The sleeve may be formed by molding or cutting the polymer composition. In one embodiment, the sleeve is configured to be positioned over a handle. The sleeve may have an outer surface configured to be gripped by a hand. For example, the sleeve may include a polymer composition, where the outer surface of the polymer composition includes a texture or other gripping surface. Optionally, the sleeve may include a layer of gripping material over the polymer composition.

[0025] 1, a tennis racket 10 is shown having a body 12. The body 12 includes a head 14 which includes a beam 15. The body also includes a shaft 16 and a handle 18.

[0026] 2 shows an exemplary embodiment of a damping material 20. In this example, the depicted damping material 20 is a strip 22. The strip 22 may be provided as individual pre-cut strips or may be provided as a roll or tape (not shown), in which case a user may custom cut the strip 22 to size. The strip 22 includes a layer 24 of a polymer composition, such as any of those disclosed herein. In one embodiment, the polymer composition may include a butyl rubber, such as any of the butyl rubber compositions disclosed herein.

[0027] Optionally, strip 22 may include an adhesive layer 26 for attaching strip 22 to the sporting goods. If adhesive layer 26 is included, strip 22 may also include a release layer or liner (not shown) on bottom surface 28 of adhesive layer 26. The release liner is removed to apply strip 22 to the sporting goods. Optionally, strip 22 may include a backing layer (not shown) on top surface 30 of polymer composition layer 24. The backing layer may be to protect the polymer material and / or may include decoration, a saying, or an image.

[0028] The strip can be of virtually any length and width depending on the desired application and the sporting equipment to which it is attached. In one embodiment, the strip has a length of about 7.62 cm to about 15.24 cm, a width of about 0.635 cm to about 0.76 cm, and a thickness of about 15 mils (0.015 inches) to about 60 mils (0.060 inches).

[0029] The polymeric material of the strips and / or damping material 34 described below may be any of the polymeric materials disclosed herein (such as a butyl rubber material) and may have one or more of the following: - A tensile strength of about 600 psi / min to about 800 psi / min, preferably about 680 psi / min to about 750 psi / min, more preferably about 722 psi / min, as measured by ASTM D412. An elongation of about 900% to 1000%, preferably about 950% to about 997%, more preferably about 985%, as measured by ASTM D412. A tear strength of about 100 pli to about 200 pli, preferably about 110 pli to about 135 pli, more preferably about 129 pli, as measured by ASTM D624. A Shore A hardness of about 40 to about 55, preferably about 44 to about 55, more preferably about 53, as measured by ASTM D2240. - Bayshore rebound of about 3% to about 7% as measured by ASTM D2632, preferably about 4% to about 6%, more preferably about 5%. an ultimate tensile strength of about 900 psi / min to about 1000 psi / min as measured by ASTM D412, preferably about 970 psi / min to about 990 psi / min, more preferably about 985 psi / min; An ultimate elongation of about 680% to 740%, preferably about 700% to about 730%, more preferably about 722%, as measured by ASTM D412.

[0030] Referring now to FIGS. 3-5, these figures show examples of damping material 20 attached to a sporting item, such as the illustrated tennis racket 10. The size, number, and placement of the damping material on the sporting item can be customized. That is, the size of the damping material can be virtually any size. The number of damping materials can be any number. The damping material can be placed in any location. In FIG. 3, the damping material 20 is attached to the beam of the head 14 on one side of the string 32. In FIG. 4, the damping material 20 is placed inside the beam above the head 14 on one side of the string 32. Optionally, the damping material 20 can be placed on the beam of the head 14 on the other side of the string 32. The damping material 20 can be aligned or offset. In FIG. 5, the damping material 20 is placed on the beam on one side of the head 14 and one side of the string 32. Optionally, the damping material 20 can be placed on the beam on the other side of the head 14 and the other side of the string 32. Alternatively, the damping material 20 can be located on the same side of the head 14 and on opposite sides of the strings 32. Also alternatively, the damping material 20 can be located on opposite sides of the head 14 and on the same side of the strings 32. The racket is shown with two damping materials; however, it will be understood that there can be more than two damping materials and that the damping material can be located in any number of different positions. Additionally, the damping material can be located on the outside of the beam or on the inside of a hollow beam.

[0031] Referring now to FIG. 6 , another embodiment of the damping material 34 is shown. The damping material 34 may be provided as a strip, sheet, or tape. The damping material 34 includes a layer 36 of a polymer composition and one or more outer layers 38 of a grip material. The layer 36 of the polymer composition and the outer layer 38 may be bonded to one another in any suitable manner. For example, an adhesive layer 40 may be used to bond the layer 36 of the polymer composition to the outer / grip layer 38. In another embodiment, the layers may be thermally bonded, or the outer layer 38 may be interlocked with the layer 36 of the polymer composition. Optionally, the damping material may also include an adhesive layer 42 for attaching the damping material to the sports equipment. If the adhesive layer 42 is not present, the layer of the polymer composition may be applied directly to the surface of the sports equipment. For example, polymer compositions such as the butyl rubber compositions disclosed herein may have sufficient tack to allow the damping material 34 (as a strip, sheet, or tape) to be applied directly to the surface of the sports equipment without the use of an intervening adhesive layer. That is, the polymer composition, when employed without an adhesive layer, may have sufficient tack such that the damping material can adequately adhere, bond, or attach to sports equipment. Referring to Figure 6A, an enlarged top view of one end 35 of damping material 34 is shown. End 35 includes a top surface 37 and opposite side surfaces 39 and 41. One or both of side surfaces 39 and 41 may taper inwardly toward the ends of the damping material. This may be a continuous taper, or the taper may be horizontal toward the ends of the damping material.

[0032] The layer 36 of polymer composition may have a thickness, measured between the upper surface 36a and the lower surface 36b, of 14 mils (0.014 inches) to 25 mils (0.025 inches), preferably about 0.018 inches. The length and width of the layer of polymer composition may vary depending on its intended use. In one embodiment, the length may be about 50 inches, and the width may be about 0.50 inches. The layer 36 of polymer composition, which may be any of the polymer compositions described herein, may be formed by a calendering process. In such a process, the polymer is heated and calendered between two or more rollers to form a continuous sheet. The thickness of the sheet may depend on the size of the gap between the last two rollers. Optionally, the calendering process may include a set of rollers that form a surface finish. For example, these may affect the gloss and texture of the surface. Optionally, the process of forming the layer of polymer composition may include vulcanizing the polymer. After the sheet is formed, the sheet is cut into the desired shape, e.g., strip / tape. Cutting may be done by any suitable method, such as laser, water jet, die cutting, etc. If adhesive and grip layers are used, these layers may be applied before or after cutting the sheet to the desired shape.

[0033] In one embodiment, the polymer layer of the damping material 34 and / or strip 20 disclosed above may be any of the polymer materials disclosed herein (such as a butyl rubber material) and may have one or more of the following: A Shore A hardness of about 45 to about 75, preferably about 55 to about 65, more preferably about 60, as measured by ASTM D2240. - A tensile strength of about 1,050 psi / min to about 1950 psi / min as measured by ASTM D412, preferably about 1,400 psi / min to about 1,600 psi / min, more preferably about 1,500 psi / min. An elongation of about 300% to 400% as measured by ASTM D412, preferably about 325% to 375%, more preferably about 350%.

[0034] In FIGS. 7a-d, the damping material 34 is provided as a tape, roll, or elongated strip to be applied to the shaft or handle of a sporting item, such as the shaft 16 or handle 18 of a tennis racket. The damping material 34 may be cut after being wrapped around the shaft 16 or handle 18. As described above, the damping material 34 may include a bottom adhesive layer 42 (FIG. 6) for attaching the damping material to the handle. Alternatively, if the polymer composition 36 has sufficient adhesive properties, the damping material may not include an intervening adhesive layer, and the polymer composition 36 may be applied directly to the surface of the handle. The damping material 34 may form or form part of the overgrip or undergrip of a tennis racket. Additionally, the damping material 34 may be placed on the racket during manufacturing. Alternatively, a user may apply the damping material to the racket after it has been released to the market.

[0035] 8 and 9, a sporting item such as a golf club 50 is shown having a shaft 52. The shaft 52 includes a grip 54 in the form of a sleeve 56. As shown in FIG. 9, the sleeve 56 includes a bore 58 for receiving the shaft 52. The sleeve 56 may be made of or may include a polymer composition. The sleeve 56 may be molded or cut to a desired sleeve shape. Optionally, the sleeve may include a core 60 made of a polymer composition and an outer layer 62 made of a grip material. Optionally, one or more damping strips, such as any of those disclosed herein, may be disposed on the shaft 52 or golf club head 53.

[0036] Butyl rubber Butyl rubber is a copolymer of isobutylene and small amounts of isoprene. In the unvulcanized state, butyl rubber is a weak material with the typical properties of a plastic gum, lacking a distinct elastic limit; that is, when subjected to slow tensile stress, it can be stretched almost indefinitely without breaking, and it exhibits virtually no elastic recovery after the stress is removed. On the other hand, vulcanized or cured butyl rubber is a strong, non-plastic material with an elastic limit and the ability to return to its original length substantially after being stretched several hundred percent.

[0037] In one embodiment of the present disclosure, the unsaturation in the butyl polymer or butyl rubber derived from the isoprene component can simultaneously impart damping properties to the polymer compound as well as anti-aging and antibacterial properties. In one embodiment, the unsaturation range of the butyl rubber is 1.65 to 2.60 mol % unsaturation. In another embodiment, the unsaturation ranges from 0.7 mol % to 2-45 mol % unsaturation. Lower unsaturation levels can result in lower crosslink density, potentially improving damping properties, but can also result in poorer stress / strain and cure properties. In one embodiment, the butyl rubber is crosslinked with a phenol-formaldehyde resin vulcanization or sulfur crosslinked. Butyl rubber is well known in the art and is described in U.S. Pat. No. 3,031,423, column 1, lines 15-24. The low unsaturation butyl rubber may contain 0.5 to 1.1 mole percent isoprene and 98.9 to 99.5 mole percent isobutylene and may be prepared by any of the well-known prior art methods, such as those described in U.S. Pat. No. 2,356,128.

[0038] Alternatively, useful impact-modifying rubbers include, for example, thermoplastic elastomeric polymer resins. The impact-modifying rubbers may be selected, for example, from: Polybutadiene, polyisobutylene, ethylene-propylene copolymers, ethylene-propylene-diene terpolymers, sulfonated ethylene-propylene-diene terpolymers, polychloroprene, poly(2,3-dimethylbutadiene), nitrile-butadiene rubber (NBR), hydrogenated nitrile-butadiene rubber (HNBR), poly(butadiene-co-pentadiene), chlorosulfonated polyethylene, polysulfide elastomers, block copolymers composed of segments of glassy or crystalline blocks such as polystyrene, poly(vinyl toluene), poly(t-butyl styrene), polyesters, and the like, and elastomeric blocks such as polybutadiene, polyisoprene, ethylene-propylene copolymers, ethylene-butylene copolymers, polyetheresters, and the like, such as those in the poly(styrene-butadiene-styrene) block copolymers manufactured by Shell Chemical Company under the trade name KRATON.

[0039] In one embodiment, the butyl rubber is present in the composition in a range of about 45% to 65% of the total weight of the formulation. Alternatively stated, the butyl rubber may be present in the following percent weight of the formulation: 45; 45.5; 46; 46.5; 47; 47.5; 48; 48.5; 49; 49.5; 50; 50.5; 51; 51.5; 52; 52.5; 53; 53.5; 54; 54.5; 56; 56.5; 57; 57.5; 58; 58.5; 59; 59.5; 60; 60.5; 61; 61.5; 62; 62.5; 63; 63.5; 64; 64.5; and about 65. In another embodiment, the butyl rubber may be present in the composition in the following weight percents: 45; 45.1; 45.2; 45.3; 64.7; 64.8; 64.9; and 65. The butyl rubber content may be present in a range defined by any two of the above numbers.

[0040] Phenol-formaldehyde resin The curing agent can be a phenol-formaldehyde resin, which is prepared by condensing phenol with formaldehyde in the presence of phenol and a base. Representative curing agents include 2,6-dihydroxymethyl-4-alkylphenol and its polycyclic condensation polymers. Examples are described in U.S. Pat. No. 2,701,895. Curing occurs by reaction of the methylol groups of the phenol or resin with the uncured rubber to form a crosslinked structure.

[0041] In one embodiment, a polymer composition is formed by curing butyl rubber with a low amount of a phenol-formaldehyde resin having a low level of ether crosslinking. Such improved properties may include improved high temperature aging properties, faster cure rates, and better stress / strain properties. The polymer composition may include such a resin, uncured butyl rubber, a halogen-containing compound, and optionally a filler and a processing oil.

[0042] Base-catalyzed phenol-formaldehyde resins can be made by condensing phenol with formaldehyde in the presence of a base. This reaction forms phenol-alcohols, which can then undergo condensation reactions to form polycyclic phenols. Examples of polycyclic phenol-formaldehyde resins are shown below. [ka]

[0043] As shown, the phenolic moieties are bridged by R'. These bridge moieties, R', can be the same or different and can be either methylene (-CH2-) or dimethylene ether (-CH2-O-CH2). The integer n can have a value from 0 to 10, preferably from 0 to 5. It is preferred that the integer n has a value high enough to ensure that the resin is solid. The group R is an alkyl group, a cycloalkyl group, a cycloalkylalkyl group, an aryl group, or an aralkyl group. It can contain up to about 12 carbon atoms. In one embodiment, the R group is an alkyl group containing up to 8 carbon atoms, particularly methyl, tert-butyl, or tert-octyl. See U.S. Pat. No. 2,701,895 for further examples, which are incorporated herein by reference.

[0044] Resin-cured butyl rubber with improved properties can be obtained by curing with a phenol-formaldehyde resin having a low level of ether bridges. In one embodiment, the molar ratio of dimethylene ether bridges to methylene bridges in the phenol-formaldehyde resin is less than about 2.5:1 or less than about 1.7:1, and most preferably less than about 1:1. Examples of suitable phenol-formaldehyde resins that can be used include resins having a molar ratio of dimethylene ether bridges to methylene bridges of about 0.65:1.

[0045] In one embodiment, butyl rubber compositions require a small amount of a diene comonomer, typically isoprene, to enable the composition to undergo crosslinking or curing. Butyl rubber grades can be distinguished by their isoprene content and Mooney viscosity (related to molecular weight). Examples of uncured butyl rubbers have about 0.5 mol% to about 10 mol% isoprene. The butyl rubbers contain about 0.5 to about 2.5 mol% isoprene, or about 0.9 to about 2.1 mol% isoprene. Particularly, butyl rubbers having about 1-4 to about 1.6 mol% isoprene are mentioned. Some suitable butyl rubbers have a Mooney viscosity of about 25 to about 70, preferably about 30 to about 63 (RPML1+8@125°C).

[0046] In one embodiment, a halogen is present in the formulation. Examples of halogen-containing compounds include organic compounds such as olefin-containing polymers with pendant chlorine atoms, such as polychloroprene available under trademarks such as Bayer, Distagul, and Neoprene. In one embodiment, the amount present in the formulation ranges from about 1 to about 10 parts by weight, or about 4 to about 6 parts by weight, or about 5 parts by weight per about 95 parts of uncured butyl rubber. Alternatively, a chlorine-containing salt, such as stannous chloride, can be used as the halogen-containing compound. The necessary halogen, such as chlorine or bromine atoms, can be provided as a component of one of the other components of the formulation, rather than as a separately added compound such as polychloroprene or stannous chloride. For example, chlorinated or brominated butyl rubber or chlorinated or brominated polycyclic phenol-formaldehyde resin can be used instead of a separately added compound such as polychloroprene or stannous chloride. In one embodiment, non-halogenated butyl rubber and non-halogenated phenol-formaldehyde resin are used. The halogen is added, for example, in polychloroprene or stannous chloride.

[0047] As an alternative to PF resins, haloalkylated PF resins, such as bromomethylated PF resins, can be used. The alkylation range of the alkyl PF resins is about 8% to 12.5%. Bromomethyl alkylated phenolic resins are described in U.S. Pat. No. 2,972,600, the contents of which are incorporated herein by reference, and are prepared by brominating a phenolic material selected from the group consisting of 2-hydroxymethyl 4-alkylphenols, 2,6-dihydroxymethyl 4-alkylphenols, hydroxymethyl 4-alkylphenols, and 4-alkylphenols, wherein the hydroxymethyl 4-alkylphenols have an average of up to four phenolic units, with a mixture of 0.5 to 2.1 moles of formaldehyde per mole of phenol. The alkyl groups contain 4 to 20 carbon atoms. The average bromine content of the brominated material is about 1 to about 9 percent.

[0048] In one embodiment, a low unsaturation butyl rubber containing a bromomethyl alkylated phenolic resin and a metal halide is used.

[0049] In one embodiment, the PF resin is present in the composition in a range of about 5% to 15% of the total weight of the formulation. Alternatively stated, the PF resin may be present in the following percent weight of the formulation: 5; 5.5; 6; 6.5; 7; 7.5; 8; 8.5; 9; 9.5; 10; 10.5; 11; 11.5; 12; 12.5; 13; 13.5; 14; 14.5; and 15.

[0050] In another embodiment, the PF resin may be present in the composition in the following weight percents: 5; 5.1; 5.2; 5.3; 14.7; 14.8; 14.9; and 15. The PF resin content may also be present in a range defined by any two of the above numbers.

[0051] Other hardeners Butyl rubber compositions can also be crosslinked in many different ways: sulfur, both in the form of rubber sulfur (S8) or polymeric sulfur (insoluble sulfur) (Sx), is used together with various accelerators such as thiazoles, sulfenamides, guanidines, carbamates, thiurams, alkylphenol disulfides, thiomorpholines, dioximes, phosphorodithioates, aniline and its derivatives.

[0052] Halogenated butyl rubbers, including brominated isobutylene-co-paramethylstyrene (BIMSM), can also be used. Halogenated butyl rubbers can also be crosslinked with a crosslinking coagent, such as thiourea, metal oxides or chlorides, or peroxides.

[0053] Filler Fillers can be added to the formulation, examples of which include talc, calcium carbonate, clay, silica, titanium dioxide, carbon black, aluminum silicate, hydrated aluminum silicate, kaolin, montmorillonite, calcium carbonate, and quartz.

[0054] The carbon black ranges from N-770 to N-110. In one embodiment, the carbon black is N-351 classified according to ASTM D1765 (see Maurice Morton, "Rubber Technology," 3rd Edition, Chapman & Hall, New York, 1995, pages 69-70, which is incorporated herein by reference). In another embodiment, the carbon black is N550.

[0055] In one embodiment, the filler is present in an amount of about 5% to about 45% of the total weight of the formulation. In another embodiment, two or more fillers may be present, each filler being present in an amount of about 5% to about 45% of the total weight of the formulation. Stated differently, the fillers may be present in the following percent weight of the formulation: 5; 5.5; 6; 6.5; 7; 7.5; 8; 8.5; 9; 9.5; 10; 10.5; 11; 11.5; 12; 12.5; 13; 13.5; 14; 14.5; 15; 15.5; 16; 16.5; 17; 17.5; 18; 18.5; 19; 19.5; 20; 20.5; 21; 21.5; 22; 22.5; 23; 23 .5;24;24.5;25;25.5;26;26.5;27;27.5;28;28.5;29;29.5;30;30.5;31;31.5;32;32.5;33;33.5;34;34.5;35;35.5;36;36.5;37;37.5;38;38.5;39;39.5;40;40.5;41;41.5;42;42.5;43;43.5;44;44.5; and 45.

[0056] In another embodiment, one or more fillers may be present in the composition individually in the following weight percents: 5; 5.1; 5.2; 5.3, 44.7; 44.8; 44.9; and 45.

[0057] In one embodiment, the formulation contains two or more fillers. In one embodiment, a first filler is present in the formulation in an amount ranging from about 5% to about 15% by weight of the formulation. In an embodiment in which a second filler is present, the second filler is present in an amount ranging from about 20% to 35% by weight of the formulation.

[0058] The formulation may contain a processing oil. Many suitable processing oils are known to those skilled in the art. Examples of suitable processing oils include castor oil and paraffin oil.

[0059] Zinc oxide may be added as an activator, suitably in an amount up to about 8 parts per 100 parts rubber, preferably about 5 parts per 100 parts rubber. Stearic acid may also be added to help solubilize the zinc oxide in the formulation.

[0060] The butyl rubber compounds described can be prepared by mixing the above-mentioned butyl rubber compounding components and additionally other desired optional components such as accelerators, extenders, lubricants, plasticizers, etc., by any convenient method used in the rubber industry, for example on a mill or in an internal mixer.

[0061] Vulcanizates can be made from the compounds by converting the compounds into any desired shape and size and vulcanizing at elevated temperatures.

[0062] In another embodiment, the formulation includes uncured butyl rubber, a halogen-containing compound, and a polycyclic phenol-formaldehyde resin having dimethylene ether bridges and methylene bridges, wherein the molar ratio of dimethylene ether bridges to methylene bridges is less than about 2.5:1. The ratio of uncured butyl rubber to the polycyclic phenol-formaldehyde resin is less than 10:1 and can be as high as 5:1.

[0063] The product can be formulated to facilitate the formation of strips, sheets, tapes, rolls, films, shapes, moldings, slabs, tapes, coatings, perforated sheets, corrugations, laminates, beads, spray foams and any desired shape for damping purposes.

[0064] In one aspect, the vibration damping composition comprises a carbon-containing nanomaterial. In yet another aspect, the multi-layer article comprises a vibration damping composition comprising a carbon-containing nanomaterial.

[0065] In other embodiments, the compositions described herein may include a plurality of carbon-containing nanomaterials.

[0066] The carbon-containing nanomaterials used are not particularly limited. The carbon nanotubes can be single-walled carbon nanotubes (SWCNTs) or double-walled carbon nanotubes (DWCNTs). DWCNTs can be obtained by any means, including, for example, catalytic chemical vapor deposition. Such preparation techniques can yield approximately 80% DWCNTs with diameters in the range of 1 to 3 nm and lengths that can reach 100 μm. The electrical conductivity of such nanotubes can exceed 25 S / cm when pressed into pellet form.

[0067] Other carbon nanotubes include multi-walled nanotubes (MWCNTs). MWCNTs can be obtained by vapor deposition in the presence of a supported catalyst, as described in PCT published patent application WO 03 / 002456 A2. Transmission electron microscopy of MWCNTs prepared in this manner can reveal that nearly 100% of the tubes are MWCNTs. Such MWCNTs can have diameters ranging from 10 to 50 nm and lengths that can reach 70 μm. The electrical conductivity of such MWCNTs can exceed 20 S / cm when pressed into pellet form.

[0068] SWCNTs, DWCNTs, and MWCNTs can be purified by washing with acid solutions (such as sulfuric and hydrochloric acids) to remove residual inorganic and metallic impurities. SWCNTs can also be non-covalently modified by encapsulating the nanotubes in cross-linked amphiphilic copolymer micelles, as described by Kang and Taton in Journal of the American Chemical Society, vol. 125, 5650 (2003). In another embodiment, carbon nanotubes can be surface functionalized, for example, as described by Wang, Iqbal, and Mitra in Journal of the American Chemical Society, vol. 128, 95 (2006).

[0069] Other carbon-containing nanomaterials include, for example, carbon nanofibers.

[0070] Examples of suitable nanofibers include submicron Vapor Grown Carbon Fibers (s-VGCF) with very small diameters (20-80 nm), high aspect ratios (>100), and highly graphitic structures (>60%), available as Grupo Antolin Carbon Nanofibers (GANF) from Grupo Antolin, Spain.

[0071] Alternatively, Pyrograf®-III is available in diameters ranging from 70 to 200 nanometers and lengths estimated at 50 to 100 microns, and is available from Applied Sciences, Inc. (ASI) of Cedarville, Ohio.

[0072] In yet another embodiment, the vibration damping compositions described herein may further comprise non-carbon-containing nanomaterials, such as, for example, silica nanoparticles, zirconia nanoparticles, and alumina nanoparticles, TiO2, clay, indium tin (oxide), iron oxide, zinc oxide, and combinations thereof.

[0073] The compositions described herein may further include pigments, flow control additives, antioxidants, curing compounds, co-curing agents, cure accelerators, inert fillers such as mineral fillers, flame retardants, processing aids such as extrusion aids (including fluoropolymer-based processing aids, lubricants such as mineral oils and waxes), glass bubbles, polymeric bubbles (such as Dualite® Hollow Composite Microsphere Fillers available from Pierce and Stevens, Corp., Buffalo, NY), and other additives.

[0074] Molded articles can also be formed that include a carbon-containing nanomaterial; a curable matrix; and a block copolymer that includes functional and non-functional blocks, but no blocks that are incompatible with the curable matrix. In these molded articles, the carbon-containing nanomaterial can be dispersed in the curable matrix. In some embodiments, the curable matrix is ​​electrically non-conductive, while the composite article itself is electrically conductive.

[0075] Molded articles include, for example, sleeves, shafts, handles, frames, supports, bodies, etc. In some embodiments, the compositions described herein allow for efficient and / or uniform dispersion of carbon-containing nanomaterials, which may result in desirable properties such as improved tensile strength, elastic modulus, flexibility, electrical conductivity, thermal conductivity, and viscoelastic vibration damping.

[0076] In some embodiments, the cured compositions described herein have a tan delta value that is at least 20% higher than a comparable cured composition containing a cured matrix lacking a carbon-containing nanomaterial described herein. In other embodiments, the tan delta value of the cured compositions described herein increases by 20% or more, 25% or more, 35% or more, or 50% or more compared to a cured composition containing a cured matrix lacking a carbon-containing nanomaterial and a block copolymer described herein.

[0077] The polymer composition may also have antimicrobial properties. Therefore, one or more formulations in a desired shape can be used not only for damping and impact modification, but also for the additional microbial resistance that the material has to offer. In one embodiment, the material is lighter in weight and has a longer service life compared to comparable products on the market.

[0078] Generally speaking, the polymer composition provides one or more of the following physical properties in its use: impact dampening; acoustic dampening; vibration dissipation; cushioning for comfort; sound reduction; lightweight; longer lifespan; antimicrobial properties; resistance to exposure to air; and UV resistance.

[0079] The polymer composition can be used in a variety of applications. Some examples include grips for sporting goods (tennis rackets, golf clubs, hockey sticks, mouth guards, football helmets, etc.), seats (for motorcycles or chairs), footwear (including soles, inserts, toe pads, etc.), electronics (computers, cell phones, disk drives, etc.), vehicles, automobile interiors and roofs, kitchen appliances, outboard motors, braking systems, medical devices, etc. Further applications include automotive underhood insulation, automotive floor panels, benchtop laboratory equipment, architectural wall panels, cell phone cases, compressor motors, coatings, computer pads, dishwasher walls, percussion (drum) damping, films, optical instruments, (lasers), integrated components, medical devices, seat cushions, slabstock, etc.

[0080] For example, in view of the physical properties of the present polymer composition, the following exemplary applications are mentioned: vibration I. Isolation of benchtop labware II. Tennis racket impact III. Football helmet IV. Integrated System Manufacturers V. Seat cushion noise VI. Architectural wall panels VII. Compressor motor VIII. Dishwasher Wall IX. Drum damping material X. Textiles and Surfaces XI. Antibacterial Coatings or Surfaces / Disposable Antibacterial Textile Products [Example]

[0081] Experiment and evaluation of damping characteristics Some samples were analyzed using a dynamic mechanical analyzer (DMA) to measure the tan delta value, ie, the ratio of loss modulus E'' to storage modulus E'. 1. Material REB5A-55 with a durometer A hardness of 55 2. REB5A-45 material with a durometer A hardness of 45 3.Comparison Material – Otter Box Phone Case 4.Comparison Material - Belkin Phone Case 5. Comparison Material – Wilson Yellow Mouthguard 6. Comparison Materials - Riddell Helmets and Armor - Black Foam 7. Comparison Material - Spalding Neoprene Material - Black with Blue Lining, Square Material 8.Comparative Materials – Moon Gel Damping Pads 9. Comparison Material - Sorbothane 0208060-50-10 (50 durometer hardness)

[0082] REB5A materials were tested at two different hardness values ​​(45 and 55 durometer A) and compared to commercially available materials from competitors. Seven materials were tested for comparison. The primary objective of the test was to obtain tan δ and E' values ​​from nine samples at room temperature (26±1°C) and vibration frequencies of 10 Hz, 20 Hz, 50 Hz, and 100 Hz using DMA. These measurements were reported in the competitor's technical data sheets. Tan δ, also known as the damping constant in DMA terminology, is generally related to the energy dissipation properties of the material being tested. E' is the storage modulus and is related to the stiffness of the material. Tan d measures the ratio of the loss modulus E'' to the storage modulus E'.

[0083] A Netzch 242 DMA was used in tension mode. A static force of 0 N and a dynamic force of 5 N were used with a force coefficient of 1.01 and an amplitude of 50 μm. Testing was performed at room temperature (26±1°C) and at frequencies of 10 Hz, 20 Hz, 50 Hz, and 100 Hz. Table 1 summarizes the DMA results. Results are listed in order of highest to lowest tan8 values. Table 2 calculates the percent improvement in tan delta values ​​for the materials of the present disclosure relative to the comparative material.

[0084] The 45 and 55 durometer A hardness proprietary materials (REB5A-45 and REB5A-55) provided the highest tan8 values ​​among all the samples tested, and therefore, these materials would have excellent mechanical energy attenuation properties under the conditions tested.

[0085] The storage modulus, E', of the materials corresponded well to the physical stiffness of the samples. However, this stiffness, expressed as E', did not appear to correlate directly with the damping performance, expressed as tan δ. For example, low stiffness materials (low E' values) did not correspond to the high damping levels (high tan δ values) that one might traditionally expect.

[0086] [Table 1]

[0087] [Table 2]

[0088] [Table 3]

Claims

1. a material configured to be attached to the article; the material comprises a polymer composition comprising butyl rubber and a phenol-formaldehyde resin; the butyl rubber content is in the range of 45% to 65% by weight of the polymer composition; A vibration damping material, wherein the content of the phenol-formaldehyde resin is in the range of 5% to 15% by weight of the polymer composition.

2. The vibration damping material of claim 1 , wherein the material is configured to be associated with a body.

3. 3. The vibration damping material of claim 2, wherein the body comprises a sporting item, a grip, a handle, a tennis racket, a golf club, a hockey stick, a mouth guard, a helmet, a seat, footwear, a shoe sole, a shoe insert, a toe pad, an electronic device, a computer, a cell phone, a disk drive, a vehicle, an automobile interior, an automobile roof, a kitchen appliance, an outboard motor, a braking system, a medical device, an automobile underhood insulation, an automobile floor panel, a benchtop lab instrument, an architectural wall panel, a cell phone case, a compressor motor, a coating, a computer pad, a dishwasher wall, a percussion instrument, a drum, a film, an optical instrument, a laser, an integrated component, a seat cushion, or a slabstock.

4. The vibration damping material according to any one of claims 1 to 3, wherein the material comprises a layer.

5. 5. The vibration damping material of claim 4, wherein the material is configured to directly contact and attach to a surface.

6. The vibration damping material of claim 4 further comprising a strip or sheet comprising said layer of material.

7. 7. The vibration damping material of claim 6, wherein the strip or sheet comprises a tape, the tape comprising the material layer and an adhesive layer.

8. The vibration damping material of claim 4 further comprising a plurality of strips or sheets comprising said layer of material.

9. The vibration damping material of claim 4 further comprising a layer of grip material.

10. 10. The method of claim 9, further comprising a layer of adhesive between the layer of grip material and the layer of material.

11. the body includes a frame; The vibration damping material of claim 2 , wherein the material is associated with the frame.

12. the body includes a shaft; The vibration damping material of claim 2 , wherein the material is associated with the shaft.

13. the body includes a handle; The vibration damping material of claim 2 , wherein the material is associated with the handle.

14. The vibration damping material of claim 2 including a grip comprising said material, said grip being associated with said body.

15. a sleeve comprising said material; The vibration damping material of claim 2 , wherein the sleeve is positioned over a handle of the body.

16. the body comprises a tennis racket including a head; The vibration-damping material of claim 2 , wherein the material is attached to the head.

17. the body comprises a tennis racket including a handle; The vibration damping material of claim 2 wherein the material is attached to the handle.

18. the body comprises a tennis racket including a handle; The vibration damping material of claim 2 wherein a sleeve containing the material is disposed over the handle.

19. The vibration damping material according to any one of claims 1 to 3, wherein the polymer composition further comprises at least one filler.

20. 20. The vibration-damping material of claim 19, wherein the content of the at least one filler ranges from about 5% to about 45% by weight of the composition.

21. 20. The vibration damping material of claim 19, wherein the filler is selected from talc, calcium carbonate, clay, silica, titanium dioxide, carbon black, aluminum silicate, hydrated aluminum silicate, kaolin, montmorillonite, calcium carbonate, quartz, and mixtures thereof.

22. The vibration damping material according to any one of claims 1 to 3, wherein the polymer composition has a Shore A hardness ranging from about 35 to about 65.

23. 4. The vibration damping material according to claim 1, wherein the polymer composition has a loss factor greater than 0.30 at 10 Hz and greater than 0.60 at 100 Hz, the loss factor being measured in dynamic mechanical analysis as the ratio of loss modulus to storage modulus.

24. The vibration damping material according to any one of claims 1 to 3, wherein the butyl rubber is an isobutylene / isoprene rubber.

25. The vibration damping material according to any one of claims 1 to 3, wherein the polymer composition further comprises stearic acid.

26. The main body and a vibration damping material associated with the body, the vibration damping material comprising a polymer composition including butyl rubber and a phenol-formaldehyde resin; Including, The butyl rubber content ranges from 45% to 65% by weight of the polymer composition, and the phenol-formaldehyde resin content ranges from 5% to 15% by weight of the polymer composition.

27. 27. The article of claim 26, wherein the body comprises a tennis racket.

28. 27. The article of claim 26, wherein the body comprises a medical device.

29. 27. The article of claim 26, wherein the body comprises a sheet.

30. 27. The article of claim 26, wherein the body comprises a seat cushion.

31. 27. The article of claim 26, wherein the body comprises a grip, a handle, a tennis racket, a golf club, a hockey stick, a mouth guard, a helmet, a seat, footwear, a shoe sole, a shoe insert, a toe pad, an electronic device, a computer, a cell phone, a disk drive, a vehicle, an automotive interior, an automotive roof, a kitchen appliance, an outboard motor, a braking system, an automotive underhood insulation, an automotive floor panel, a benchtop lab instrument, an architectural wall panel, a cell phone case, a compressor motor, a coating, a computer pad, a dishwasher wall, a percussion instrument, a drum, a film, an optical instrument, a laser, an integrated component, or a slabstock.

32. An article according to any one of claims 26 to 31, wherein the vibration damping material comprises a layer.

33. An article according to any one of claims 26 to 31, wherein the vibration damping material is configured to be in direct contact with and attached to a surface of the body.

34. An article according to any one of claims 26 to 31, wherein the vibration damping material comprises a strip or sheet comprising a layer of a polymer composition.

35. 35. The article of claim 34, wherein the strip or sheet comprises a tape, the tape comprising the layer of the polymer composition and an adhesive layer.

36. An article according to any one of claims 26 to 31, wherein the vibration damping material further comprises a plurality of strips or sheets comprising layers of the polymer composition.

37. An article according to any one of claims 26 to 31, wherein the vibration dampening material comprises a layer of gripping material associated with a layer of the polymer composition.

38. 38. The article of claim 37, further comprising a layer of adhesive between the layer of grip material and the layer of polymer composition.

39. the body includes a frame; An article according to any one of claims 26 to 31, wherein the vibration damping material is associated with the frame.

40. the body includes a shaft; An article according to any one of claims 26 to 31, wherein the vibration damping material is associated with the shaft.

41. the body includes a handle; An article according to any one of claims 26 to 31, wherein the vibration dampening material is associated with the handle.

42. the vibration damping material includes a grip; An article according to any one of claims 26 to 31, wherein the grip is associated with the body.

43. the vibration damping material includes a sleeve; An article according to any one of claims 26 to 31, wherein the sleeve is positioned over a handle of the main body.

44. the body comprises a tennis racket including a head; 27. The article of claim 26, wherein the vibration damping material is attached to the head.

45. the body comprises a tennis racket including a handle; 27. The article of claim 26, wherein the vibration dampening material is attached to the handle.

46. the body comprises a tennis racket including a handle; 27. The article of claim 26, wherein the vibration dampening material comprises a sleeve disposed over the handle.

47. The article of any one of claims 26 to 31, wherein the polymer composition further comprises at least one filler.

48. 48. The article of claim 47, wherein the content of the at least one filler ranges from 5% to 45% by weight of the composition.

49. 49. The article of claim 48, wherein the filler is selected from talc, calcium carbonate, clay, silica, titanium dioxide, carbon black, aluminum silicate, hydrated aluminum silicate, kaolin, montmorillonite, calcium carbonate, quartz, and mixtures thereof.

50. The article of any one of claims 26 to 31, wherein the polymer composition has a Shore A hardness ranging from about 35 to about 65.

51. 32. The article of any one of claims 26 to 31, wherein the polymer composition has a loss factor greater than 0.30 at 10 Hz and greater than 0.60 at 100 Hz, the loss factor being measured in dynamic mechanical analysis as the ratio of loss modulus to storage modulus.

52. 32. An article according to any one of claims 26 to 31, wherein the butyl rubber is an isobutylene / isoprene rubber.

53. The article of any one of claims 26 to 31, wherein the polymer composition further comprises stearic acid.

54. a racket including a body having a head and a handle, the head including a beam having an inner beam surface; a string on the beam, wherein a first portion of the beam inner surface is on a first side of the string and a second portion of the beam inner surface is on a second side of the string; a vibration damping material comprising at least one elongated strip, the at least one elongated strip including a first elongated strip attached to the first portion of the inner surface of the beam only on the first side of the string; Sports equipment.

55. 55. The sporting item of claim 54, wherein the vibration-damping material is in direct contact with the interior surface of the beam.

56. 55. The sporting item of claim 54, wherein the at least one elongated strip includes a second elongated strip attached to the second portion of the inner beam surface on the second side of the string.

57. 55. The sporting article of claim 54, wherein the at least one elongated strip comprises a layer of a polymer composition and an adhesive layer for attaching the elongated strip to the inner surface of the beam.

58. 55. The sporting item of claim 54, further comprising a second vibration damping material associated with the handle.

59. 59. Sports equipment according to any one of claims 54 to 58, wherein the racket comprises a tennis racket.

60. the vibration damping material comprises a polymer composition including butyl rubber and phenol-formaldehyde resin; the butyl rubber content is in the range of 45% to 65% by weight of the polymer composition; 59. The sports equipment according to any one of claims 54 to 58, wherein the content of the phenol-formaldehyde resin is in the range of 5% to 15% by weight of the polymer composition.

61. 61. The sporting goods of claim 60, wherein the phenol-formaldehyde resin comprises a bromomethylated alkylphenol-formaldehyde resin.

62. 61. The sporting item of claim 60, wherein the polymer composition further comprises at least one filler.

63. 63. The sporting goods of claim 62, wherein the content of said at least one filler ranges from 5% to 45% by weight of said polymer composition.

64. 61. The sporting article of claim 60, wherein the polymer composition has a Shore A hardness ranging from about 35 to about 65.

65. 61. The sporting goods of claim 60, wherein the polymer composition has a loss factor greater than 0.30 at 10 Hz and greater than 0.60 at 100 Hz, the loss factor being measured in dynamic mechanical analysis as the ratio of loss modulus to storage modulus.

66. 61. The sporting goods of claim 60, wherein the butyl rubber is an isobutylene / isoprene rubber.

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