Golf ball outer layer material composition, golf ball and manufacturing method of golf ball

Abstract

The invention discloses a golf ball outer layer material composition, a golf ball and a manufacturing method of the golf ball, and relates to the technical field of ball sports equipment. The invention relates to an outermost layer material composition of a golf ball. The outermost layer material composition comprises 60-70 parts of thermoplastic polyurethane; 7-12 parts of a composite flow modifier; 4-8 parts of an interface enhancing system; 0.3 to 0.8 part of an antioxidant; 2-4 parts of color master batch; wherein the composite flow modifier is a compound of dioctyl adipate and polycaprolactone in a mass ratio of (2-3): 1; the interface reinforcing system comprises 3-5 parts of maleic anhydride grafted polyolefin elastomer and 1-3 parts of core-shell structure coated particles; the core-shell structure coated particle takes nano silicon dioxide as a core and an ethylene-vinyl acetate copolymer oligomer as a shell, and the mass ratio of the core to the shell is 1: (2-3). Through the dual synergistic effect of the composite flow modifier and the interface reinforcing system, the problems of flow eccentricity and interlayer bonding of the outermost layer material of the golf ball are systematically solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ball sports equipment, in particular to a golf outer layer material composition, a golf ball and a manufacturing method thereof. BACKGROUND

[0002] The three-layer structure (core-middle layer-outermost layer) of the golf ball is the current mainstream design, in which the outermost layer directly determines the flight performance (such as spin rate, flight distance) and durability (such as impact resistance, delamination resistance) of the ball, and the material selection and forming process play a key role in product quality. The outermost layer of the existing three-layer golf ball mostly uses thermoplastic polyurethane as the base resin, but it has the following two core technical problems: (1) The melt viscosity of thermoplastic polyurethane is relatively high, and the flowability is poor. When wrapping the middle layer through the extrusion process, the material cannot spread uniformly along the outer surface of the middle layer, and the local area will form a thickness difference due to flow lag, which causes the geometric center of the outermost layer structure to deviate from the core, affecting the stability of the ball hitting.

[0003] (2) The thermoplastic polyurethane of the outermost layer is a polar polyurethane structure, and the middle layer is mostly a non-polar ethylene-vinyl acetate copolymer / polyolefin elastomer composite elastomer. The chemical compatibility of the two is poor, and the interface is only combined by physical adsorption, and the bonding strength is usually ≤1.5 MPa. Under repeated ball hitting or high-speed impact, the outermost layer and the middle layer are prone to delamination, which causes the golf ball to break and the durability to decrease significantly.

[0004] To solve the above problems, the existing technology mostly uses the scheme of increasing the extrusion temperature or adding a single compatibilizer, but there are obvious defects: the former increases the extrusion temperature to above 200℃, which causes the molecular chain of thermoplastic polyurethane to break down and degrade, and the mechanical properties such as tensile strength and elongation at break decrease by 10-15%; the latter cannot form a continuous interface bonding layer with a single compatibilizer, and the interface bonding strength decays by more than 30% over time due to the migration of the compatibilizer.

[0005] Therefore, there is an urgent need for a technology that optimizes and innovates the outermost layer material to solve the problems of outermost layer eccentricity caused by poor material flowability and weak interface bonding between the outer layer and the middle layer. The above is a technical problem that needs to be solved by the general technical personnel in the field at present.

[0006] The information disclosed in this BACKGROUND section is only intended to increase an understanding of the general context in which the present application can be practiced. It is not admitted that the information constitutes prior art that is already known in the art. SUMMARY

[0007] In order to solve the above technical problems, the embodiment of the present application provides a golf outer layer material composition, a golf ball and a manufacturing method thereof.

[0008] The technical concept of the golf outer layer material composition, the golf ball and the manufacturing method thereof provided by the present application is as follows: (I) For the outermost layer eccentricity problem, the present application adopts a compound combination of dioctyl adipate + polycaprolactone to form a dynamic and stable viscosity reduction system.

[0009] The role of dioctyl adipate (DOA): as a small molecule plasticizer, it quickly inserts between TPU molecular chains, expands the interchain distance, and instantaneously reduces the initial melt viscosity through the lubricating effect between molecular chains, thereby improving the flowability during extrusion startup.

[0010] The role of polycaprolactone (PCL): as a low molecular weight polyester partially compatible with TPU, its long-chain molecules can form entanglement and micro-region compatible structure with TPU molecular chains. This structure not only provides a lasting plasticizing effect, but more importantly, it can stabilize the melt structure, prevent local migration of DOA and viscosity recovery, and ensure that the melt viscosity remains stable and uniform throughout the extrusion process.

[0011] (II) For the weak interlayer bonding problem, the present application adopts a binary system of maleic anhydride grafted polyolefin elastomer (MAH-g-POE) + core-shell structure coated particles to build a dual bonding mechanism of "chemical bonding + physical anchoring".

[0012] The role of MAH-g-POE: as a chemical bridging agent, its maleic anhydride functional group can covalently bond with the hydroxyl group of the intermediate layer EVA (ethylene-vinyl acetate copolymer) and the amino or urea group at the chain end of TPU at processing temperature, forming a firm chemical connection at the interface.

[0013] The role of core-shell structure coated particles: as a physical anchoring point; its shell layer (EVA oligomer) is highly compatible with the intermediate layer EVA material and can melt and embed into the intermediate layer during processing. The core layer (nano-SiO2) acts as a rigid nanoparticle, which is wrapped in the TPU matrix. This structure makes a single particle like a rivet, with its EVA shell anchored in the intermediate layer and its SiO2 core locked in the outermost layer TPU, forming a strong mechanical interlocking structure.

[0014] II. A golf outer layer material composition, comprising: thermoplastic polyurethane 60-70 parts; composite flow modifier 7-12 parts; interfacial reinforcement system 4-8 parts; antioxidant 0.3-0.8 parts; Color masterbatch 2-4 parts; wherein, The complex flow modifier is a compound of dioctyl adipate and polycaprolactone with a mass ratio of 2-3:1; The interface reinforcing system includes maleic anhydride grafted polyolefin elastomer 3-5 parts and core-shell structure coated particles 1-3 parts. The core-shell structure coated particles have nanosilica as the core and ethylene-vinyl acetate copolymer oligomer as the shell, and the mass ratio of the core to the shell is 1:2-3.

[0015] The number average molecular weight of the ethylene-vinyl acetate copolymer oligomer is 3000-8000.

[0016] Preferably, the golf intermediate layer material is composed of the following components by mass fraction: Ethylene-vinyl acetate copolymer 70 parts; Polyolefin elastomer 30 parts; Dicumyl peroxide 1-2 parts; Antioxidant 1010 0.3-0.8 parts.

[0017] Preferably, the number average molecular weight of the thermoplastic polyurethane is 20000-30000; and the number average molecular weight of the ethylene-vinyl acetate copolymer oligomer is 3000-8000.

[0018] Preferably, the antioxidant is a compound of antioxidant 1010 and antioxidant 168 with a mass ratio of 1:1.

[0019] Preferably, the preparation method of the core-shell structure coated particles comprises the following steps: (1) Nanosilica pretreatment: nanosilica is added to a silane coupling agent (γ-glycidoxypropyltrimethoxysilane) ethanol solution with a mass concentration of 5-8%, stirred at 60-70°C for 1-1.5h, filtered and dried at 80-100°C for 2-3h to obtain surface-modified nanosilica; (2) Ethylene-vinyl acetate copolymer oligomer solution preparation: ethylene-vinyl acetate copolymer oligomer is added to xylene and stirred at 70-80°C until completely dissolved to prepare an oligomer solution with a mass concentration of 15-20%; (3) Core-shell coating: the surface-modified nanosilica obtained in step (1) is added to the oligomer solution of step (2) with a solid-liquid ratio of 1:5-8 (g:mL), and stirred at 75-85°C for 2-3h to make the oligomer uniformly adhere to the surface of the nanosilica; (4) drying and shaping: the mixed system obtained in step (3) is subjected to distillation under reduced pressure (vacuum degree -0.08 to -0.09 MPa) at 50-60°C to remove the solvent, and then is kept at 100-120°C for 1-1.5 h, and after cooling, is ground and sieved (2000 mesh) to obtain core-shell structure coated particles with a particle size of 50-100 nm.

[0020] A golf ball comprising a ball core, an intermediate layer and an outermost layer arranged coaxially from inside to outside in sequence; The outermost layer is made of the material composition of claim 1 or 2; The intermediate layer is a composite elastomer of ethylene-vinyl acetate copolymer and polyolefin elastomer with a mass ratio of 7:3; The intermediate layer further comprises 1-2 parts of dicumyl peroxide as a crosslinking agent, and 0.3-0.8 parts of antioxidant 1010; The ball core is a butadiene rubber-based elastomer.

[0021] A manufacturing method of the golf ball as described above, comprising the following steps: (1) butadiene rubber, vulcanizing agent, accelerator are mixed in a mass ratio of 90-95:2-3:1-1.5, and vulcanized at 150-160°C for 20-30 min to prepare the ball core; (2) ethylene-vinyl acetate copolymer, polyolefin elastomer, dicumyl peroxide, antioxidant 1010 are mixed according to the proportion, and are melt-extruded by an extruder to prepare an intermediate layer blank, and are wrapped outside the ball core by an injection molding process, and are crosslinked at 160-170°C for 30-40 min to obtain a ball core-intermediate layer composite; (3) the outer surface of the intermediate layer of the ball core-intermediate layer composite is subjected to plasma treatment, the treatment power is 250-350 W, and the treatment time is 20-40 s; (4) the material composition is added to an extruder, the melt material is uniformly wrapped outside the pretreated ball core-intermediate layer composite under the conditions of segmented temperature control and screw rotation speed of 30-50 r / min, and after cooling and shaping, the golf ball is obtained.

[0022] Preferably, the cis content of butadiene rubber is ≥98%; the vulcanizing agent is sulfur; and the accelerator is diphenyl disulfide.

[0023] Preferably, in step (4), the segmented temperature control program includes: feeding section 170-175°C, compression section 180-185°C, homogenization section 185-190°C, and head 180-185°C.

[0024] Preferably, in step (4), the length-diameter ratio of the screw of the extruder is 25:1, and the compression ratio is 3:1.

[0025] The golf ball outer layer material composition, golf ball and manufacturing method provided by the embodiment of the present application have the following beneficial effects: (1) The present application significantly reduces the melt viscosity of thermoplastic polyurethane by the synergistic effect of the composite flow modifier, and improves the melt flow stability; the system not only realizes the instantaneous reduction of melt viscosity, but also ensures the uniformity of viscosity during the entire extrusion process, so that the melt can flow uniformly along the surface of the intermediate layer; in combination with the optimized extrusion process parameters, the uniform distribution of the outermost layer thickness is realized, the eccentricity is controlled within the range allowed by the industry, thereby ensuring the stability and consistency of the flight distance of the golf ball.

[0026] (2) The innovative interface enhancement system of the present application establishes a firm interlayer bonding interface through the dual action mechanism of chemical bonding and physical anchoring; the chemical bridging agent forms a stable covalent bond at the interface, and the core-shell structure particles realize effective mechanical interlocking through their special structural design; this multiple bonding mechanism significantly enhances the interlayer bonding strength, so that the golf ball can withstand the impact load of long-term repeated hitting, effectively prevents the occurrence of interlayer peeling, and greatly prolongs the service life of the product.

[0027] (3) The entire technical solution of the present application embodies the high synergy of material formula and manufacturing process, the preparation process of the core-shell particles is stable and reliable, and is suitable for large-scale production; the good compatibility between the material components ensures the long-term stability of the performance; the entire solution does not need to increase complex production equipment or process steps, and realizes the significant improvement of product performance on the premise of moderate increase in cost, and has good industrial application prospect. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0029] In view of the above technical problems, the embodiments of the present application provide a golf ball outer layer material composition, a golf ball and a manufacturing method thereof to solve the problems raised in the background art.

[0030] The technical effects of the present application will be further illustrated by specific embodiments and comparative examples. All the embodiments and comparative examples use the same ball core and intermediate layer formula, only the outermost layer material composition (including the preparation process of core-shell structure coated particles) or process parameters are different.

[0031] 1. Experimental material preparation Thermoplastic polyurethane: Shore D hardness 53, number average molecular weight 25000, melt flow rate (190°C, 2.16 kg) 10 g / 10 min (purchased from BASF); Complex flow modifier: dioctyl adipate (analytically pure), polycaprolactone (number average molecular weight 10000, analytically pure); Interface reinforcing system: Maleic anhydride grafted polyolefin elastomer (purchased from DuPont); Core-shell structure coated particles (self-made, see 1.1 for specific preparation steps); Antioxidant: antioxidant 1010, antioxidant 168 (analytically pure, purchased from Ciba); Intermediate layer raw material: ethylene-vinyl acetate copolymer (vinyl acetate content 28%), polyolefin elastomer (melt index 15 g / 10 min), dicumyl peroxide (crosslinking agent, analytically pure); Spherical core raw material: butadiene rubber (cis content 98%), sulfur, benzothiazyl disulfide (accelerator); Core-shell coated particle preparation auxiliary materials: nano-silica (particle size 20-30 nm, analytically pure), silane coupling agent (γ-glycidoxypropyltrimethoxysilane, analytically pure), ethylene-vinyl acetate copolymer oligomer (number average molecular weight 5000, vinyl acetate content 28%), xylene (analytically pure), ethanol (analytically pure).

[0032] 1.1 Preparation of core-shell structure coated particles (1) Nano-silica pretreatment: weigh 10 g of nano-silica and add it to 200 mL of a 6% silane coupling agent (γ-glycidoxypropyltrimethoxysilane) ethanol solution, place it in a constant temperature water bath at 65°C and magnetically stir (speed 400 r / min) for 1.2 h to allow the silane coupling agent to fully graft onto the surface of the nano-silica; then collect the solid product by vacuum filtration (filter membrane pore size 0.22 μm) and place it in a vacuum drying oven at 90°C for 2.5 h to remove residual ethanol, obtaining surface-modified nano-silica; (2) Ethylene-vinyl acetate copolymer oligomer solution preparation: weigh 25 g of ethylene-vinyl acetate copolymer oligomer (number average molecular weight 5000) and add it to 125 mL of xylene, place it in a three-necked flask and magnetically stir (speed 300 r / min) at 75°C for 1.5 h until the oligomer is completely dissolved, preparing a 16.7% oligomer solution by mass concentration; (3) Core-shell coating: the surface modified nano-silica obtained in step (1) was added into the oligomer solution of step (2) at a solid-liquid ratio of 1:6 (g:mL), kept at a constant temperature of 78°C, and magnetically stirred (speed 500 r / min) for 2.5 h. During this period, the dispersion state of the particles was monitored in real time by a dynamic light scattering instrument to ensure that the oligomer was uniformly attached to the surface of the nano-silica to form a core-shell precursor; (4) Drying and shaping: the core-shell precursor mixture obtained in step (3) was transferred into a rotary evaporator, and distilled under reduced pressure at 55°C and a vacuum degree of -0.085 MPa for 3 h to remove the xylene solvent. Then, the dried solid was transferred into a muffle furnace and kept at 110°C for 1.2 h to further remove residual small molecular impurities. After cooling to room temperature, it was ground in an agate mortar and sieved through a 2000 mesh sieve. Finally, core-shell structure coated particles (with nano-silica as the core and ethylene-vinyl acetate copolymer oligomer as the shell) with a particle size of 80-90 nm and a core-shell mass ratio of 1:2.5 were obtained.

[0033] 2. Example 1 2.1 Composition of the outermost layer material Thermoplastic polyurethane 65 parts, composite flow modifier (dioctyl adipate 6 parts + polycaprolactone 3 parts) 9 parts, interface enhancement system (maleic anhydride grafted polyolefin elastomer 4 parts + self-made core-shell coated particles 2 parts) 6 parts, antioxidant (antioxidant 1010 / antioxidant 168 = 1:1) 0.5 parts, black masterbatch 3 parts.

[0034] 2.2 Golf ball manufacturing steps (1) Preparation of the core: weigh butadiene rubber 92 parts, sulfur 2.5 parts, and dibenzothiazyl disulfide 1.2 parts, and put them into a planetary mixer with 5 parts of anhydrous ethanol as a dispersant, and mix at a speed of 300 r / min for 2 h. Then, the mixture is loaded into a spherical vulcanization mold and placed in a vacuum vulcanization furnace at 155°C for 25 min. After cooling, the core with a diameter of 32 mm and a Shore D hardness of 28 is obtained. (2) Middle layer wrapping: weigh ethylene-vinyl acetate copolymer 70 parts, polyolefin elastomer 30 parts, dicumyl peroxide 1.5 parts, and antioxidant 1010 0.5 parts, and add them into an extruder (screw length-diameter ratio 30:1, compression ratio 4:1). Set the speed to 190 r / min and the segmented temperature to 160-165-170°C (feeding section-compression section-homogenization section). Melt extrusion to prepare the middle layer blank. Use an injection molding machine to wrap the blank around the core, crosslink at 165°C for 35 min, and then cool to obtain a core-middle layer composite with a thickness of 2.0 mm and a Shore D hardness of 38. (3) Intermediate layer surface pretreatment: the ball core-intermediate layer complex was placed into a plasma treatment instrument, the treatment power was set to 300 W, the treatment time was set to 30 s, and oxygen was used as the treatment gas (flow rate of 10 L / min); after treatment, the water contact angle was measured to be 34° using a contact angle measuring instrument, and the surface roughness Ra was measured to be 0.52 μm using a laser confocal microscope; (4) Outermost layer extrusion wrapping: the outermost layer material composition was added to an extruder (length-diameter ratio of 25:1, compression ratio of 3:1), and the segmented temperature control was set as follows: feeding section 172°C, compression section 182°C, homogenization section 188°C, and die head 183°C, and the screw rotation speed was set to 40 r / min; the pretreated ball core-intermediate layer complex was fixed to the extruder die core, and the molten outermost layer material was uniformly wrapped around the complex outside the die core, and the wet film thickness of the outermost layer was controlled to be 1.2 mm; then it was transferred to a cooling and shaping machine, and cooled in a 28°C circulating water for 8 min, and after drying, a golf ball product with an outermost layer thickness of 0.8 mm was obtained.

[0035] 3. Example 2 3.1 Outermost layer material composition Thermoplastic polyurethane 60 parts, composite flow modifier (dioctyl adipate 6 parts + polycaprolactone 2 parts) 8 parts, interface enhancement system (maleic anhydride grafted polyolefin elastomer 5 parts + the above-mentioned 1.1 self-made core-shell coated particles 1 part) 6 parts, antioxidant (antioxidant 1010 / antioxidant 168 = 1:1) 0.3 parts, white masterbatch 2 parts.

[0036] 3.2 Manufacturing steps Except for the adjustment of the outermost layer material components, the remaining steps (including the preparation of core-shell coated particles, the preparation of the ball core, the wrapping of the intermediate layer, the plasma treatment, and the extrusion of the outermost layer) were completely consistent with Example 1, and only the wet film thickness was controlled to be 1.5 mm during the extrusion of the outermost layer, and the thickness of the outermost layer was adjusted to be 1.0 mm after cooling and shaping.

[0037] 4. Example 3 4.1 Outermost layer material composition Thermoplastic polyurethane 70 parts, composite flow modifier (dioctyl adipate 7 parts + polycaprolactone 3 parts) 10 parts, interface enhancement system (maleic anhydride grafted polyolefin elastomer 3 parts + the above-mentioned 1.1 self-made core-shell coated particles 3 parts) 6 parts, antioxidant (antioxidant 1010 / antioxidant 168 = 1:1) 0.8 parts, red masterbatch 4 parts.

[0038] 4.2 Manufacturing steps Except for the adjustment of the outermost layer material components, the remaining steps were consistent with Example 1, and the wet film thickness was controlled to be 0.9 mm during the extrusion of the outermost layer, and the thickness of the outermost layer was adjusted to be 0.6 mm after cooling and shaping.

[0039] 5. Comparative Example 1 (single flow modifier without polycaprolactone) 5.1 Outermost layer material composition Thermoplastic polyurethane 65 parts, single flow modifier (dioctyl adipate 9 parts) 9 parts, interfacial reinforcement system (maleic anhydride grafted polyolefin elastomer 4 parts + self-made core-shell coated particles 2 parts) 6 parts, antioxidant (antioxidant 1010 / antioxidant 168 = 1:1) 0.5 parts, black masterbatch 3 parts (remove polycaprolactone).

[0040] 5.2 Manufacturing steps Completely consistent with Example 1, only the composite flow modifier is replaced by single dioctyl adipate, and the core-shell coated particles are still prepared by the self-made process of 1.1.

[0041] 6. Comparative Example 2 (single interfacial system without core-shell coated particles) 6.1 Outermost layer material composition Thermoplastic polyurethane 65 parts, composite flow modifier (dioctyl adipate 6 parts + polycaprolactone 3 parts) 9 parts, single interfacial compatibilizer (maleic anhydride grafted polyolefin elastomer 6 parts) 6 parts, antioxidant (antioxidant 1010 / antioxidant 168 = 1:1) 0.5 parts, black masterbatch 3 parts (remove core-shell coated particles).

[0042] 6.2 Manufacturing steps Completely consistent with Example 1, only the interfacial reinforcement system is replaced by single maleic anhydride grafted polyolefin elastomer, and no 1.1 self-made core-shell coated particles are added.

[0043] 7. Comparative Example 3 (no composite flow modifier + no core-shell coated particles) 7.1 Outermost layer material composition Thermoplastic polyurethane 65 parts, single flow modifier (dioctyl adipate 9 parts) 9 parts, single interfacial compatibilizer (maleic anhydride grafted polyolefin elastomer 6 parts) 6 parts, antioxidant (antioxidant 1010 / antioxidant 168 = 1:1) 0.5 parts, black masterbatch 3 parts (no polycaprolactone + no core-shell coated particles).

[0044] 7.2 Manufacturing steps Completely consistent with Example 1, the conventional scheme of "single flow modifier + single interfacial compatibilizer" is adopted, and no polycaprolactone and 1.1 self-made core-shell coated particles are added.

[0045] 8. Performance test method and results The core performance of the golf ball products of Examples 1-3 and Comparative Examples 1-3 was tested, and the test standards and results are shown in Table 1: Table 1

[0046] The experimental data in Table 1 clearly demonstrates that the present application solves the two core problems in golf ball manufacturing through the synergistic design of material components, and brings about a significant improvement in comprehensive performance.

[0047] (1) Synergistically solve the flow eccentricity, realize excellent flight stability The melt flow rate of Comparative Example 3 (conventional scheme) is the lowest (7.8 g / 10 min), and the eccentricity is the worst (0.18 mm), which confirms that the poor flowability of TPU is the root cause of eccentricity as described in the background art.

[0048] The melt flow rate (8.5 g / 10 min) and eccentricity (0.12 mm) of Comparative Example 1 (using only DOA) are better than the conventional scheme, but still not ideal, proving that a single small molecule plasticizer cannot achieve stable and uniform flow.

[0049] The data of Examples 1-3 show that after using DOA / PCL composite flow modifier, the melt flow rate is significantly improved to 10.8-11.5 g / 10 min. This data directly reflects the effective reduction of melt viscosity and the fundamental improvement of flowability.

[0050] Mechanism of action: DOA provides transient viscosity reduction, and PCL provides persistent and stable viscosity reduction through molecular chain entanglement, and the two work together to ensure that the melt always maintains extremely high flow uniformity during the wrapping process.

[0051] Direct results: Ultimately reflected in the eccentricity being stably controlled at a very low level of 0.04-0.06 mm, far below the industry threshold of 0.2 mm.

[0052] Terminal performance improvement: This structural improvement directly translates into excellent flight performance. The flight distances of all examples are above 259 yards, and the spin rate fluctuation range is extremely narrow (≤1.8%). This indicates that the center of gravity of the golf ball is extremely stable, the flight trajectory is highly predictable, and the ball consistency is fundamentally guaranteed.

[0053] (2) Double mechanism to strengthen interface bonding, realize durability breakthrough The interface bonding strength of Comparative Example 3 (conventional scheme) is only 1.6 MPa, and serious delamination occurs after 1500 hits, confirming the unreliability of single physical adsorption and weak interface bonding.

[0054] The bonding strength (2.5 MPa) of Comparative Example 2 (using only MAH-g-POE) is improved, but local delamination still occurs, proving that single "chemical bonding" is still not enough to withstand long-term dynamic fatigue impact.

[0055] The interfacial bonding strength of Examples 1-3 increased to 3.8-4.3 MPa, which is more than 2.5 times that of conventional solutions. More importantly, all examples showed no delamination after 1500 strokes.

[0056] Mechanism of action: MAH-g-POE establishes a strong covalent bond, providing a high-strength bonding foundation. The core-shell coated particles act like "microscopic rivets," forming an effective mechanical interlock through the fusion of the EVA shell and the intermediate layer, and the locking between the SiO2 core and TPU. This structure can disperse stress and prevent crack propagation.

[0057] Synergistic effect: Data shows that only by combining the two (as in Example 1) can high bonding strength (4.1 MPa) and excellent fatigue resistance (no delamination) be obtained simultaneously, achieving a qualitative leap in durability.

[0058] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications to the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the invention. All variations and improvements should fall within the protection scope defined by the claims of this invention.

Claims

1. A golf outermost layer material composition, characterized by, Comprise: Thermoplastic polyurethane 60-70 parts; Composite flow modifier 7-12 parts; Interface reinforcing system 4-8 parts; Antioxidant 0.3-0.8 parts; Color masterbatch 2-4 parts; wherein, The composite flow modifier is a compound of dioctyl adipate and polycaprolactone with a mass ratio of 2-3:1; The interface reinforcing system comprises maleic anhydride grafted polyolefin elastomer 3-5 parts and core-shell structure coated particles 1-3 parts; The core-shell structure coated particles have nanosilica as core and ethylene-vinyl acetate copolymer oligomer as shell, and the mass ratio of core to shell is 1:2-3.

2. The golf outermost layer material composition according to claim 1, wherein, The golf intermediate layer material is composed of the following components by mass fraction: Ethylene-vinyl acetate copolymer 70 parts; Polyolefin elastomer 30 parts; Dicumyl peroxide 1-2 parts; Antioxidant 1010 0.3-0.8 parts.

3. The golf outermost layer material composition according to claim 1, wherein, The number average molecular weight of the thermoplastic polyurethane is 20000-30000; the number average molecular weight of the ethylene-vinyl acetate copolymer oligomer is 3000-8000.

4. The golf outermost layer material composition according to claim 1, wherein, The antioxidant is a compound of antioxidant 1010 and antioxidant 168 with a mass ratio of 1:

1.

5. The golf outermost layer material composition according to claim 1, wherein, The preparation method of the core-shell structure coated particles comprises the following steps: (1) Add nanosilica to an ethanol solution of silane coupling agent with a mass concentration of 5-8%, stir at 60-70°C for 1-1.5h, filter, and dry at 80-100°C for 2-3h to obtain surface-modified nanosilica; (2) Add ethylene-vinyl acetate copolymer oligomer to xylene, stir at 70-80°C until completely dissolved, and prepare an oligomer solution with a mass concentration of 15-20%; (3) Add the surface-modified nanosilica obtained in step (1) to the oligomer solution of step (2) with a solid-liquid ratio of 1:5-8, stir at 75-85°C for 2-3h to make the oligomer uniformly adhere to the surface of the nanosilica; (4) Remove the solvent from the mixed system obtained in step (3) by distillation under reduced pressure at 50-60°C, then heat at 100-120°C for 1-1.5h, cool, grind and sieve to obtain core-shell structure coated particles with a particle size of 50-100nm.

6. A golf ball characterized by, Comprise a ball core, an intermediate layer and an outermost layer arranged coaxially from inside to outside; The outermost layer is made of the material composition of claim 1 or 2; The intermediate layer is a composite elastomer of ethylene-vinyl acetate copolymer and polyolefin elastomer with a mass ratio of 7:3; The intermediate layer further comprises 1-2 parts of dicumyl peroxide as a crosslinking agent and 0.3-0.8 parts of antioxidant 1010; The ball core is a butadiene rubber-based elastomer.

7. A method of making a golf ball as defined in claim 6, wherein Comprise the following steps: (1) Mix butadiene rubber, vulcanizing agent and accelerator with a mass ratio of 90-95:2-3:1-1.5, vulcanize at 150-160°C for 20-30min to prepare the ball core; (2) ethylene-vinyl acetate copolymer, polyolefin elastomer, dicumyl peroxide, antioxidant 1010 are mixed according to the proportion, melt extruded by an extruder to form an intermediate layer blank, then wrapped outside the ball core by an injection molding process, crosslinked at 160-170℃ for 30-40min to obtain a ball core-intermediate layer composite; (3) the outer surface of the intermediate layer of the ball core-intermediate layer composite is treated by plasma, the treatment power is 250-350W, and the treatment time is 20-40s; (4) the material composition of claim 1 or 2 is added to an extruder, the melt is uniformly wrapped outside the pretreated ball core-intermediate layer composite under the conditions of segmented temperature control and screw rotation speed of 30-50r / min, and after cooling and setting, the golf ball is obtained.

8. The method of manufacturing a golf ball according to claim 7, wherein In step (1), the cis content of butadiene rubber is ≥98%; the vulcanizing agent is sulfur; and the accelerator is dibenzothiazyl disulfide.

9. The method of manufacturing a golf ball according to claim 7, wherein In step (4), the segmented temperature control program includes: feeding section 170-175℃, compression section 180-185℃, homogenization section 185-190℃, and head 180-185℃.

10. The method of manufacturing a golf ball according to claim 7, wherein In step (4), the length-diameter ratio of the screw of the extruder is 25:1, and the compression ratio is 3:1.

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