Adhesive composition for artificial turf, artificial turf, and preparation methods therefor

Abstract

The present application belongs to the technical field of artificial turf. Disclosed are an adhesive composition for artificial turf, artificial turf and preparation methods therefor. The adhesive composition for artificial turf comprises the following components by mass percentages: 10-50% of an ethylene-vinyl acetate copolymer emulsion in which the average particle size of latex particles is less than 3 μm; 5-40% of a functional resin emulsion in which the average particle size of latex particles is less than 3 μm; 0.1-10% of a surfactant; and 0-80% of an inorganic filler. The composition is an aqueous system, the requirement for the environment is low during a gum production process, a gum-coated turf bottom side has a good bonding strength, and the bonding strength of an inner single grass yarn, which is the most difficult to permeate, of the artificial turf is still kept well in a high-temperature and high-humidity environment after hot water aging.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to the Chinese patent application with filing No. 2024119426669, filed with the Chinese Patent Office on December 26, 2024, entitled "ADHESIVE COMPOSITION FOR ARTIFICIAL TURF, ARTIFICIAL TURF AND PREPARATION METHODS THEREFOR", the contents of which are incorporated herein by reference in their entirety. TECHNICAL FIELD

[0002] Artificial turf mainly consists of three parts, namely, synthetic grass yarn fibers resembling grass blades, a backing fabric used for implanting synthetic fibers, and an adhesive layer playing a fixing role. After more than half a century of development, grass yarns have evolved from nylon in the first generation to polypropylene in the second and then to polyethylene in the third. The soft hand feel, appearance and athletic performance have become more and more similar to those of the natural grass, and are widely accepted by users. When the artificial turf is laid on fields for sports such as soccer, American football, hockey and the like, there are quite strict requirements for the adhesive used to fix the grass yarns. How to secure the grass yarns and keep them from falling off for several years or even more than ten years is a very important performance.

[0003] From the beginning of the birth of artificial turf, manufacturers have used styrenebutadiene rubber and polyurethane adhesives as adhesive layers. A matrix resin used in styrenebutadiene rubber is butadiene-styrene copolymer, which is mainly produced through emulsion polymerization. A certain amount of emulsifier is added during the polymerization process. To improve the bonding force, a significant number of products are modified by adding a certain amount of a third monomer containing carboxylic acid units. Due to the presence of hydrophilic emulsifiers and carboxylic acid monomers, the water resistance of the styrene-butadiene rubber is poor. After prolonged periods of rainy weather, the mechanical properties of the adhesive layers deteriorate significantly, failing to meet the use requirements for sports fields subjected to high-intensity activity. Two-component polyurethane adhesive is another adhesive widely used by manufacturers, favored for its excellent bonding strength and good water resistance and weather resistance. However, the environmental requirements of the production process are too high. Especially on rainy days or under conditions of relatively high humidity in summer, moisture in the air may react with isocyanate monomers in the adhesive, destroying the originally designed structure of the overall adhesive layer, producing artificial turf with poor bonding strength, and laying hidden dangers for later quality.

[0004] With the gradual popularization of artificial turf, more and more sports fields around the world have begun to be laid with it, which puts forward higher requirements for the mechanical properties of the adhesive layer in extreme environments. In recent years, we have found that in some areas with high demand for sports activities, after a rainy day, the whole turf is still in a high-temperature high-humidity environment after direct sunlight, and sports lovers begin to play football on the field. At this time when the mechanical properties of the adhesive layer of the turf are weakest, long-term sports lead to the falling off of grass yarns. Existing artificial turf backing adhesive technology generally has a problem of poor mechanical properties at both a production end and a product use end. In particular, the innermost single grass yarn of the whole cluster of grass yarns of the artificial turf is always the weakest link of the whole mechanical properties. Therefore, it is necessary to develop an artificial turf backing adhesive that has low environmental requirements during production and is resistant to high temperature and high humidity during use, improving the single-yarn pull-out force property of the innermost grass yarn in extreme environments, thereby meeting the growing demand of the market.

[0005] The application of ethylene-vinyl acetate in artificial turf has also been studied in the prior art, but the content of ethylene structural units thereof is insufficient, resulting in that the selection of raw materials is insufficient to provide help for the mechanical properties of the innermost single grass yarn in extreme environments. The ethylene-vinyl acetate copolymer is also used as one of the raw materials, but its adhesive is uniformly coated on one side of the non-woven fabric by means of heating and then dripping, and the surface of the non-woven fabric is pressed onto the back surface of the base backing fabric of the artificial turf by means of hot-pressing, which essentially uses the traditional coating method for the hot melt adhesive. Due to the high viscosity of the adhesive during hot melting, which cannot be compared with the permeability of an aqueous system, it is difficult to penetrate into the inside of the grass roots, resulting in poor mechanical properties of the innermost single grass yarn in the extreme environments of high temperature and high humidity.

[0006] Therefore, how to develop an adhesive composition for artificial turf, artificial turf and preparation methods therefor is a technical problem that urgently needs to be solved by those skilled in the art. BACKGROUND ART

[0007] Artificial turf mainly consists of three parts, namely, synthetic grass yarn fibers resembling grass blades, a backing fabric used for implanting synthetic fibers, and an adhesive layer playing a fixing role. After more than half a century of development, grass yarns have evolved from nylon in the first generation to polypropylene in the second and then to polyethylene in the third. The soft hand feel, appearance and athletic performance have become more and more similar to those of the natural grass, and are widely accepted by users. When the artificial turf is laid on fields for sports such as soccer, American football, hockey and the like, there are quite strict requirements for the adhesive used to fix the grass yarns. How to secure the grass yarns and keep them from falling off for several years or even more than ten years is a very important performance.

[0008] From the beginning of the birth of artificial turf, manufacturers have used styrenebutadiene rubber and polyurethane adhesives as adhesive layers. A matrix resin used in styrenebutadiene rubber is butadiene-styrene copolymer, which is mainly produced through emulsion polymerization. A certain amount of emulsifier is added during the polymerization process. To improve the bonding force, a significant number of products are modified by adding a certain amount of a third monomer containing carboxylic acid units. Due to the presence of hydrophilic emulsifiers and carboxylic acid monomers, the water resistance of the styrene-butadiene rubber is poor. After prolonged periods of rainy weather, the mechanical properties of the adhesive layers deteriorate significantly, failing to meet the use requirements for sports fields subjected to high-intensity activity. Two-component polyurethane adhesive is another adhesive widely used by manufacturers, favored for its excellent bonding strength and good water resistance and weather resistance. However, the environmental requirements of the production process are too high. Especially on rainy days or under conditions of relatively high humidity in summer, moisture in the air may react with isocyanate monomers in the adhesive, destroying the originally designed structure of the overall adhesive layer, producing artificial turf with poor bonding strength, and laying hidden dangers for later quality.

[0009] With the gradual popularization of artificial turf, more and more sports fields around the world have begun to be laid with it, which puts forward higher requirements for the mechanical properties of the adhesive layer in extreme environments. In recent years, we have found that in some areas with high demand for sports activities, after a rainy day, the whole turf is still in a high-temperature high-humidity environment after direct sunlight, and sports lovers begin to play football on the field. At this time when the mechanical properties of the adhesive layer of the turf are weakest, long-term sports lead to the falling off of grass yarns. Existing artificial turf backing adhesive technology generally has a problem of poor mechanical properties at both a production end and a product use end. In particular, the innermost single grass yarn of the whole cluster of grass yarns of the artificial turf is always the weakest link of the whole mechanical properties. Therefore, it is necessary to develop an artificial turf backing adhesive that has low environmental requirements during production and is resistant to high temperature and high humidity during use, improving the single-yarn pull-out force property of the innermost grass yarn in extreme environments, thereby meeting the growing demand of the market.

[0010] The application of ethylene-vinyl acetate in artificial turf has also been studied in the prior art, but the content of ethylene structural units thereof is insufficient, resulting in that the selection of raw materials is insufficient to provide help for the mechanical properties of the innermost single grass yarn in extreme environments. The ethylene-vinyl acetate copolymer is also used as one of the raw materials, but its adhesive is uniformly coated on one side of the non-woven fabric by means of heating and then dripping, and the surface of the non-woven fabric is pressed onto the back surface of the base backing fabric of the artificial turf by means of hot-pressing, which essentially uses the traditional coating method for the hot melt adhesive. Due to the high viscosity of the adhesive during hot melting, which cannot be compared with the permeability of an aqueous system, it is difficult to penetrate into the inside of the grass roots, resulting in poor mechanical properties of the innermost single grass yarn in the extreme environments of high temperature and high humidity.

[0011] Therefore, how to develop an adhesive composition for artificial turf, artificial turf and preparation methods therefor is a technical problem that urgently needs to be solved by those skilled in the art. SUMMARY OF THE INVENTION

[0012] In view of this, the present application provides an adhesive composition for artificial turf, artificial turf, and preparation methods therefor.

[0013] To achieve the objective, the present application adopts the following technical solutions.

[0014] An adhesive composition for artificial turf includes the following components by mass percentages:

[0015] 10-50% of an ethylene-vinyl acetate copolymer emulsion or modified ethylene-vinyl acetate copolymer emulsion with an average particle size of latex particles of less than 3 pm, where a solid content of the ethylene-vinyl acetate copolymer emulsion is 40-60%;

[0016] 5-40% of a functional resin emulsion with an average particle size of latex particles of less than 3 pm, where a solid content of the functional resin emulsion is 40-60%;

[0017] 0.1-10% of a surfactant; and

[0018] 0-80% of an inorganic filler,

[0019] where a matrix resin ethylene-vinyl acetate copolymer in the ethylene-vinyl acetate copolymer emulsion includes 10-60% of vinyl acetate structural units by mass percentage; and

[0020] a matrix resin modified ethylene-vinyl acetate copolymer in the modified ethylenevinyl acetate copolymer emulsion includes, by mass percentages, 10-60% of vinyl acetate (VA) structural units and 0.1-10% of modified monomer structural units, and modified monomers include one or more of methacrylic acid, acrylic acid, glycidyl methacrylate or maleic anhydride.

[0021] Beneficial effects of the present application: firstly, in the adhesive composition of the present application, the ethylene-vinyl acetate copolymer emulsion is introduced, the content of vinyl acetate structural units in the ethylene-vinyl acetate copolymer is further limited, ensuring that a proper proportion of non-polar ethylene units and polar vinyl acetate units enables sufficient bonding force to polyolefin grass yarns during later curing. Simultaneously, the introduction of the functional resin emulsion into the composition ensures that a viscosity of the system is reduced during melt bonding, which is beneficial to improving the penetration of the composition system to the innermost single grass yarn and fully moistening its surface to facilitate formation of desirable interfacial bond strength;

[0022] secondly, in the adhesive composition of the present application, proper surfactants, emulsion particle size and emulsion solid content are selected to ensure good flowability of the whole composition system, providing a foundation for improving the mechanical properties of the internal single grass yarns that are most difficult to penerate under extreme environments; and

[0023] finally, to further improve the bonding strength, for the adhesive composition of the present application, the inorganic fillers with higher thermal conductivity coefficient may also be combined in the selection of fillers, so that the adhesive of the aqueous system may also fully melt and bond the innermost single grass yarns of the whole cluster of grass yarns under an existing backing adhesive process to obtain ideal mechanical properties.

[0024] Through the synergistic effects of the above three aspects, the adhesive composition of the present application may endow the bottom backing with excellent bonding strength. Especially after the bottom backing has been aged in hot water, the pull-out force property of the innermost single grass yarn of the turf remains excellent in a high-temperature and high-humidity environment. Simultaneously, the method for preparing the artificial turf containing the adhesive composition of the present application is simple and not limited by the environment, and enables continuous production using the existing production line.

[0025] The composition is an aqueous system, and has low requirements for the environment in the backing adhesive production process. The bottom backing of the turf after back coating has excellent bonding strength, enabling that the bonding strength of the internal single grass yarns that are most difficult to penetrate of the artificial turf remains good in the high-temperature and high-humidity environment after hot-water aging.

[0026] Further, the adhesive composition for artificial turf includes the following components by mass percentages:

[0027] 20-40% of an ethylene-vinyl acetate copolymer emulsion with an average particle size of latex particles of less than 3 pm;

[0028] 10-30% of a functional resin emulsion with an average particle size of latex particles of less than 3 pm;

[0029] 1-5% of a surfactant; and

[0030] 25-65% of an inorganic filler.

[0031] Further, the average particle size of latex particles in the above ethylene-vinyl acetate copolymer emulsion is 0.05-2 pm.

[0032] Further, the functional resin emulsion is one or more of a terpene resin emulsion, a rosin resin emulsion or a petroleum resin emulsion.

[0033] More further, the above rosin resin emulsion includes, but not limited to, one or two of a rosin glyceride emulsion or a rosin pentaerythritol ester emulsion, and the above petroleum resin emulsion includes, but not limited to, one or more of a C5 aliphatic petroleum resin emulsion, a C9 aromatic petroleum resin emulsion, a C5-C9 copolymerized petroleum resin emulsion, a dicyclopentadiene (DCPD) alicyclic petroleum resin emulsion, or a hydrogenated modified petroleum resin emulsion.

[0034] More further, the above ethylene-vinyl acetate copolymer emulsion is prepared from ethylene and vinyl acetate by an emulsion polymerization method or is prepared from an ethylene-vinyl acetate copolymer resin by a resin emulsification method.

[0035] More further, the above modified ethylene-vinyl acetate copolymer emulsion is prepared from a modified ethylene-vinyl acetate copolymer resin by a resin emulsification method.

[0036] More further, the above ethylene-vinyl acetate copolymer emulsion is a single component or a multi-component mixture prepared by an emulsion polymerization method, or a single component or a multi-component mixture prepared by a resin emulsification method, or a multi-component mixture of an emulsion prepared by an emulsion polymerization method and an emulsion prepared by a resin emulsification method.

[0037] More further, specific steps for preparing the above ethylene-vinyl acetate copolymer emulsion by an emulsion polymerization method of ethylene and vinyl acetate are as follows:

[0038] adding deionized water, a stabilizer, an emulsifier and a dispersing auxiliary into a reaction kettle, stirring at a rotating speed of 100-200 rpm for 10-20 min to uniformly mix the materials, dividing a vinyl acetate monomer into two parts, then adding the first part of the vinyl acetate monomer, raising a temperature of the reaction kettle to 50-70°C, introducing ethylene gas, closing an ethylene valve when the pressure rises to 35-45 bar, then immediately adding an initiator into the reaction kettle to initiate a reaction, and then adding the remaining part of vinyl acetate monomer in 60-120 min, continuing to introduce ethylene gas until the pressure in the kettle is 50-60 bar, holding at the temperature for 5-6 h, then adding a defoamer and performing degassing treatment for 1-2 h to prepare the ethylene-vinyl acetate copolymer emulsion.

[0039] More further, specific steps for preparing the above ethylene-vinyl acetate copolymer emulsion or modified ethylene-vinyl acetate copolymer emulsion from an ethylene-vinyl acetate copolymer resin or a modified ethylene-vinyl acetate copolymer resin by a resin emulsification method are as follows:

[0040] adding, to a reaction kettle, deionized water, an emulsifier and ethylene-vinyl acetate copolymer resin or modified ethylene-vinyl acetate copolymer resin with a modified monomer structural unit content of 0.1-10%, starting stirring and adjusting a stirring speed to 50-150 rpm, heating to 90-150°C, simultaneously starting a dispersing device, adjusting the speed of a dispersing disc to 5,000-15,000 rpm, holding at the temperature for 10-30 min, then starting an emulsifying device, adjusting a speed of an emulsifying head to 10,000-30,000 rpm, continuing to hold at the temperature for 2-6 h, cooling to 40-60°C and discharging to obtain the ethylenevinyl acetate copolymer emulsion or modified ethylene-vinyl acetate copolymer emulsion.

[0041] More further, the above functional resin emulsion is prepared by a resin emulsification method.

[0042] More further, specific steps for preparing the above terpene resin emulsion by the resin emulsification method are as follows:

[0043] adding deionized water, an emulsifier and terpene resin into a reaction kettle, starting stirring, adjusting a stirring speed to 50-150 rpm, heating to 100- 150°C, simultaneously starting a dispersing device, adjusting a speed of a dispersing disc to 5,000-15,000 rpm, holding at the temperature for 10-30 min, then starting an emulsifying device, adjusting a speed of an emulsifying head to 8,000-25,000 rpm, continuing to hold at the temperature for 2-5 h, cooling to 40-60°C and discharging to obtain the terpene resin emulsion.

[0044] Further, the average particle size of latex particles in the above functional resin emulsion is 0.05-2 pm.

[0045] Further, the above surfactant is one or more of an anionic surfactant, a cationic surfactant or a nonionic surfactant.

[0046] More further, the above surfactant includes the anionic surfactant and nonionic surfactant.

[0047] More further, the anionic surfactant includes, but not limited to, one or more of potassium rosinate, potassium oleate, sodium polyacrylate, fatty alcohol polyoxyethylene ether sulfate, sodium a-alkenyl sulfonate, sodium dodecyl sulfate or sodium dodecyl benzene sulfonate; the cationic surfactant includes, but not limited to, one or more of dodecyl ammonium chloride, cetyltrimethyl ammonium bromide or cetylpyridinium quaternary ammonium salt; and the nonionic surfactant includes, but not limited to, one or more of polyoxyethylene ether, castor oil polyoxyethylene ether, polyethylene glycol, Span 80, Tween 80 or Tween 20.

[0048] Further, the above inorganic filler includes but not limited to one or more of calcium carbonate, mica, barium sulfate, aluminum hydroxide, magnesium hydroxide, talcum powder, wollastonite, glass microbeads, silicon dioxide, or silicon carbide.

[0049] More further, the above inorganic filler includes but not limited to one or more of calcium carbonate, aluminum hydroxide, silicon dioxide, or silicon carbide.

[0050] More further, the above adhesive composition for artificial turf further includes one or more of color paste, a defoamer or a thickener.

[0051] The present application further provides a method for preparing the adhesive composition for artificial turf, including the following steps:

[0052] (1) weighing each raw material according to the above adhesive composition for artificial turf; and

[0053] (2) mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler to obtain the adhesive composition for artificial turf.

[0054] The beneficial effects of the present application are that: the method for preparing the adhesive composition for the artificial turf is simple in process and beneficial to industrial application.

[0055] More further, in step (2), a stirring rotation speed is 400-600 rpm, and a stirring time is 30-60 min.

[0056] The present application further provides an artificial turf, including the above adhesive composition for artificial turf, artificial grass yarns, and a backing fabric, where the artificial grass yarns are tufted on the backing fabric, and the back coated surface of the backing fabric is coated with the above adhesive composition for artificial turf.

[0057] The present application further provides a method for preparing artificial turf, including the following steps:

[0058] 1) melt extruding polyethylene and / or polypropylene, drawing and spinning, and heat setting to obtain artificial grass yarns;

[0059] 2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[0060] 3) uniformly coating the adhesive composition for artificial turf on the back coated surface of the obtained semi-finished product of the artificial turf, and then drying to obtain the artificial turf.

[0061] The beneficial effects of the present application are that: the method for preparing the artificial turf in the present application is simple and beneficial to industrial application.

[0062] Further, in step 1), a melt extrusion temperature is 160-270°C, a drawing temperature is 80-120°C, a drawing ratio is 3-7, a heat-setting temperature is 80-120°C, and a retraction ratio is 0.75-0.95.

[0063] Further, in step 3), a coating weight of the adhesive composition for artificial turf is 500-1,500 g / m2.

[0064] Further, in step 3), a drying temperature is 100-150°C, and a drying time is 8-14 min. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0065] Technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It is obvious that the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present application.

[0066] Specific steps for preparing an ethylene-vinyl acetate copolymer emulsion by an emulsion polymerization method in Example 5 of the present application were as follows:

[0067] adding, according to mass percentage, 48.5% deionized water, 3% hydroxyethyl cellulose, 0.1% ethylenediaminetetraacetic acid disodium, 0.2% ammonium polycarboxylate and 1.5% fatty alcohol polyoxyethylene ether (solid content 65%) to a reaction kettle, stirring at a rotation speed of 150 rpm for 15 min, uniformly mixing materials, adjusting a pH of the materials to 4.5 by using formic acid, adding 0.01% of Mohr's salt, dividing 37.6% vinyl acetate monomer into two parts, then adding a first part of 10% vinyl acetate monomer, raising a temperature of the reaction kettle to 55°C, introducing ethylene gas, closing an ethylene valve when the pressure is increased to 40 bar, then dropwise adding 0.3% tert-butyl hydrogen peroxide and 0.6% disodium hydroxysulfinoacetate into the reaction kettle for initiating a reaction, then adding the remaining 27.6% vinyl acetate monomer within 90 min, continuing to introduce ethylene gas (introducing about 8% of ethylene gas in total over the two introudcitons) until a pressure in the kettle was 52 bar, holdingat the temperature for 5 h, adding 0.1% organic silicone defoamer (solid content of 30%) and performing degassing treatment for 2 h to prepare the ethylene-vinyl acetate copolymer emulsion.

[0068] Except the ethylene-vinyl acetate copolymer emulsion prepared by the emulsion polymerization method in Example 5, the ethylene-vinyl acetate copolymer emulsions or the modified ethylene-vinyl acetate copolymer emulsions in other examples and comparative examples were each prepared by a resin emulsification method, and the specific steps were as follows:

[0069] respectively adding ethylene-vinyl acetate copolymer resin or maleic anhydride modified ethylene-vinyl acetate copolymer resin, an emulsifier and deionized water into a reaction kettle according to the material ratio in Table 1 below, starting stirring, adjusting the stirring speed to 100 rpm, heating according to the process parameters in Table 1, simultaneously starting a dispersing device, setting the speed of a dispersing disc according to the process parameters in Table 1 below, holding at the temperature for 20 min, then starting an emulsifying device, setting a speed of an emulsifying head according to the process parameters in Table 1 below, continuing to hold at the temperature for 4 h, cooling to 40°C and discharging to obtain ethylene-vinyl acetate copolymer emulsion or maleic anhydride modified ethylene-vinyl acetate copolymer emulsion. The ethylene-vinyl acetate copolymer emulsions with VA content of 19%, D50 = 1 pm and different solid contents were involved in Examples and Comparative Examples, and were obtained by diluting the ethylene-vinyl acetate copolymer emulsion with a solid content of 65% in Table 1 below with water.

[0070] Table 1 Category Ethylene-vinyl acetate copolymer emulsion Physical property paramet er D50 (pm) 1 1 1 1 1 1 2 1 4 Solid content (%) 50 50 50 50 50 50 50 65 50 VA% 8 10 28 60 65 10 19 19 19 MAH% 0 0 0 0 0 0.6 0 0 0 Ratio of raw material s (%) Ethylene-vinyl acetate copolymer resin or maleic anhydride-modified ethylene-vinyl acetate copolymer resin 35 35 38 40 40 35 36 51 38 Potassium rosinate 8 8 7 5 5 8 8 8 6 Span 80 4 4 3 3 3 4 4 4 3 Polyoxyethyle ne octylphenol ether-10 3 3 2 2 2 3 2 2 3 Deionized water 50 50 50 50 50 50 50 35 50 Process paramet er Temperature (°C) 150 130 100 80 80 130 110 110 105 Stirring speed (rpm) 100 Dispersing speed (rpm) 1000 0 1150 0 1200 0 1200 0 1100 0 1100 0 1000 0 1250 0 1000 0 Emulsifying speed (rpm) 2300 0 2400 0 2450 0 2450 0 2350 0 2200 0 2200 0 2500 0 1800 0 Emulsifying time (h) 4

[0071] In Examples and Comparative Examples below of the present application, the functional resin emulsion was a terpene resin emulsion. The specific steps for preparing the terpene resin emulsion through a resin emulsification method were as follows:

[0072] respectively adding terpene resin, an emulsifier and deionized water into a reaction kettle according to a material ratio in Table 2 below, starting stirring, adjusting a stirring speed to 100 rpm, heating according to the process parameters in the table, simultaneously starting a dispersing device, setting the speed of a dispersing disc according to the process parameters in Table 2 below, holding at the temperature for 20 min, then starting an emulsifying device, setting the speed of an emulsifying head according to the process parameters in Table 2 below, continuing to hold at the temperuatre for 4 h, cooling to 40°C and discharging to obtain the terpene resin emulsion. The terpene resin emulsions with D50 = 1 pm and different solid contents in Examples and Comparative Examples were obtained by diluting the terpene resin emulsion with a solid content of 65% in Table 2 below with water.

[0073] Table 2 Category Terpene resin emulsion Physical property parameter D50 (pm) 1 2 4 Solid content (%) 65 50 50 Ratio of raw materials (%) Terpene resin 58 44.5 45.5 Sodium dodecyl sulfate 2 2 1.7 Styrene-polyacrylamide 5 3.5 2.8 Deionized water 35 50 50 Process parameter Temperature (°C) 130 125 Stirring speed (rpm) 100 Dispersing speed (rpm) 9000 9000 7500 Emulsifying speed (rpm) 19000 16000 15000 Emulsifying time (h) 4

[0074] Preparation of styrene-butadiene adhesive composition:

[0075] weighing the following components by mass percentages: 48% of styrene-butadiene emulsion (solid content 50%), 48% of calcium carbonate, 2% of polyacrylic acid dispersant, 1% of black slurry and 1% of organic silicone defoamer; and

[0076] adding the above components into a stirring kettle, starting the stirring device, and adjusting the stirring speed to 500 rpm and keeping for 40 min to obtain a uniformly mixed styrene-butadiene adhesive composition.

[0077] Preparation of two-component polyurethane adhesive composition:

[0078] weighing the following components by mass percentages: 13% of polyether triol (with the molecular weight of 5,000), 12% of polyether glycol (with the molecular weight of 800), 1.3% of 1,4-butanediol, 0.07% of triethylenediamine, 0.13% of nickel diacetylacetone, 0.7% of black slurry and 54% of calcium carbonate; and

[0079] adding the above components into a stirring kettle, starting a stirring device, adjusting the stirring speed to 400 rpm and keeping for 15 min to obtain component A of the two-component polyurethane adhesive composition, adding 18.8% isocyanate component B before performing back coating on artificial turf, and adjusting a stirring speed to 800 rpm and keeping for 1 min to obtain the two-component polyurethane adhesive composition.

[0080] The preparation method for artificial grass yarns in Examples and Comparative Examples of the present application included: melt extruding polyethylene at the melt extruding temperature of 220°C, drawing and spinning, and heat setting to otbain the artificial grass yarns, where the drawing temperature was 97°C, the drawing ratio was 5, the heat-setting temperature was 99°C, and the retraction ratio was 0.8.

[0081] In Examples and Comparative Examples of the present application, the adhesive composition for artificial turf was uniformly coated on the back coated surface of the obtained semi-finished product of the artificial turf, and then dried to obtain the artificial turf, where the drying temperature was 125°C, and the drying time was 12 min.

[0082] Example 1

[0083] A method for preparing artificial turf included the following steps:

[0084] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[0085] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[0086] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[0087] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[0088] Example 2

[0089] A method for preparing artificial turf included the following steps:

[0090] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 40% of calcium carbonate and 7% of silicon carbide; and

[0091] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[0092] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[0093] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1000 g / m2, and drying to obtain the artificial turf.

[0094] Example 3

[0095] A method for preparing artificial turf included the following steps:

[0096] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 10% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[0097] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[0098] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[0099] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00100] Example 4

[00101] A method for preparing artificial turf included the following steps:

[00102] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 28% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion with latex particle D50 = 1 pm (solid content 50%); a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00103] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00104] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00105] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00106] Example 5

[00107] A method for preparing artificial turf included the following steps:

[00108] (1) weighing the following components by mass percentages: 15% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, which was prepared by the emulsion polymerization method, and in which a matrix resin ethylenevinyl acetate copolymer included 85% of vinyl acetate structural units by mass percentage; 15% of the ethylene-vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, which was prepared by the resin emulsification method, and in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00109] mixing and stirring the ethylene-vinyl acetate copolymer emulsions, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00110] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00111] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00112] Example 6

[00113] A method for preparing artificial turf included the following steps:

[00114] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 60% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50=1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% calcium carbonate; and

[00115] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00116] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00117] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00118] Example 7

[00119] A method for preparing artificial turf included the following steps:

[00120] (1) weighing the following components by mass percentages: 30% of maleic anhydride modified ethylene-vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin maleic anhydride modified ethylene-vinyl acetate copolymer included, by mass percentage, 10% of vinyl acetate structural units and 0.6% of maleic anhydride structural units; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% sodium dodecyl sulfate and 0.8% castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00121] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00122] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00123] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00124] Example 8

[00125] A method for preparing artificial turf included the following steps:

[00126] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 2 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00127] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00128] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00129] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00130] Example 9

[00131] A method for preparing artificial turf included the following steps:

[00132] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 2 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00133] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00134] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00135] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00136] Example 10

[00137] A method for preparing artificial turf included the following steps:

[00138] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 40%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00139] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00140] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00141] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00142] Example 11

[00143] A method for preparing artificial turf included the following steps:

[00144] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 60%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00145] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00146] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00147] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00148] Example 12

[00149] A method for preparing artificial turf included the following steps:

[00150] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 40%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00151] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00152] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00153] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00154] Example 13

[00155] A method for preparing artificial turf included the following steps:

[00156] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 60%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate;

[00157] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00158] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00159] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00160] Example 14

[00161] A method for preparing artificial turf included the following steps:

[00162] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 3% of sodium dodecyl sulfate; and an inorganic filler which was 47% of calcium carbonate; and

[00163] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00164] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00165] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00166] Example 15

[00167] A method for preparing artificial turf included the following steps:

[00168] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 3% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00169] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00170] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00171] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00172] Examples 16-23

[00173] According to Example 1, except for the different mass percentages of the ethylenevinyl acetate copolymer emulsion, the terpene resin emulsion, the sodium dodecyl sulfate, the castor oil polyoxyethylene ether, and the calcium carbonate, the rest raw materials, steps, and parameters were the same as in Example 1.

[00174] Table 3: Table of Mass Percentages of Raw Materials in Examples 16-23 Raw material category Exampl e 16 Exampl e 17 Exampl e 18 Exampl e 19 Exampl e 20 Exampl e 21 Exampl e 22 Exampl e 23 Ethylene-vinyl acetate copolymer emulsion 10% 20% 40% 50% 30% 30% 30% 30% Terpene resin emulsion 40% 30% 10% 5% 20% 20% 20% 20% Sodium dodecyl sulfate 2.2% 2.2% 2.2% 2.2% 0.07% 0.7% 3.6% 7.3% Castor oil polyoxyethyle ne ether 0.8% 0.8% 0.8% 0.8% 0.03% 0.3% 1.4% 2.7% Calcium carbonate 47% 47% 47% 42% 49.9% 49% 45% 40%

[00175] Comparative Example 1

[00176] A method for preparing artificial turf included the following steps:

[00177] (1) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00178] (2) uniformly coating the styrene-butadiene adhesive composition on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00179] Comparative Example 2

[00180] A method for preparing artificial turf included the following steps:

[00181] (1) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00182] (2) uniformly coating the two-component polyurethane adhesive composition on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00183] Comparative Example 3

[00184] A method for preparing artificial turf included the following steps:

[00185] (1) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00186] (2) preparing an adhesive composition by referring to the method disclosed in Example 2 of the patent application No. 200780101243.2, uniformly coating on a back coated surface of the obtained semi-finished product of the artificial turf with a coating weight of 1,000 g / m2, and then drying to obtain the artificial turf.

[00187] Comparative Example 4

[00188] A method for preparing artificial turf included the following steps:

[00189] (1) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00190] (2) preparing an adhesive composition by referring to the method disclosed in Example 1 of the patent application No. 201510491592.6, heating the adhesive composition to 175°C, uniformly coating on a surface of a non-woven fabric by means of dripping, and pressing the surface of the non-woven fabric onto a back surface of the semi-finished product of the of the artificial turf by means of hot pressing.

[00191] Comparative Example 5

[00192] A method for preparing artificial turf included the following steps:

[00193] (1) weighing the following components by mass percentages: 47% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; a surfactant which was 4.4% of sodium dodecyl sulfate and 1.6% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00194] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00195] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00196] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00197] Comparative Example 6

[00198] A method for preparing artificial turf included the following steps:

[00199] (1) weighing the following components by mass percentages: 30% of ethylene-vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; and an inorganic filler which waswas 50% of calcium carbonate; and

[00200] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00201] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00202] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00203] Comparative Example 7

[00204] A method for preparing artificial turf included the following steps:

[00205] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 8% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00206] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00207] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00208] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00209] Comparative Example 8

[00210] A method for preparing artificial turf included the following steps:

[00211] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 65% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00212] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00213] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00214] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00215] Comparative Example 9

[00216] A method for preparing artificial turf included the following steps:

[00217] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 4 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00218] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00219] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00220] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00221] Comparative Example 10

[00222] A method for preparing artificial turf included the following steps:

[00223] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 4 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00224] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00225] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00226] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00227] Comparative Example 11

[00228] A method for preparing artificial turf included the following steps:

[00229] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 35%) with latex particle D50 = 1 pm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 pm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00230] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain an adhesive composition for artificial turf;

[00231] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00232] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00233] Comparative Example 12

[00234] A method for preparing artificial turf included the following steps:

[00235] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 65%) with latex particle D50 = 1 gm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 50%) with latex particle D50 = 1 gm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate;

[00236] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00237] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00238] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00239] Comparative Example 13

[00240] A method for preparing artificial turf included the following steps:

[00241] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 gm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 35%) with latex particle D50 = 1 gm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00242] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00243] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00244] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1,000 g / m2, and drying to obtain the artificial turf.

[00245] Comparative Example 14

[00246] A method for preparing artificial turf included the following steps:

[00247] (1) weighing the following components by mass percentages: 30% of the ethylene vinyl acetate copolymer emulsion (solid content 50%) with latex particle D50 = 1 gm, in which a matrix resin ethylene-vinyl acetate copolymer included 19% of vinyl acetate (VA) structural units by mass percentage; 20% of a functional resin emulsion (solid content 65%) with latex particle D50 = 1 gm; a surfactant which was 2.2% of sodium dodecyl sulfate and 0.8% of castor oil polyoxyethylene ether; and an inorganic filler which was 47% of calcium carbonate; and

[00248] mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler at a stirring rotation speed of 500 rpm for a stirring time of 40 min to obtain the adhesive composition for artificial turf;

[00249] (2) tufting the obtained artificial grass yarns on a backing fabric to obtain a semi finished product of the artificial turf; and

[00250] (3) uniformly coating the adhesive composition for artificial turf on a back coated surface of the obtained semi-finished product of the artificial turf, with a coating weight of 1000 g / m2, and drying to obtain the artificial turf.

[00251] Table 4: Table of Physical Property Parameters of Ethylene-Vinyl Acetate Copolymer Emulsion Raw material category Physical property parameter of raw material Comparat ive Example 7 Exam ple 3 Exam ple 1 Exam ple 4 Exam ple 5 Exam ple 6 Comparat ive Example 8 Exam ple 7 Ethylen e-vinyl acetate copoly mer emulsio n VA (%) 8 10 19 28 52 60 65 10 Maleic anhydri de (%) 0 0 0 0 0 0 0 0.6 D50 (gm) 1 Solid content (%) 50

[00252] Table 5: Parameter Table of Raw Material Particle Size Physical property category Physical property parameter Example 8 Comparative Example 9 Example 9 Comparative Example 10 D50 (Tm Ethylene-vinyl acetate copolymer emulsion 2 4 1 1 Terpene resin emulsion 1 1 2 4

[00253] Table 6: Parameter Table of Raw Material Solid Content Physical property category Physical property parameter Comparat ive Example 11 Exam ple 10 Exam ple 11 Comparat ive Example 12 Comparat ive Example 13 Exam ple 12 Exam ple 13 Comparat ive Example 14 Solid conte nt (%) Ethylen e-vinyl acetate copoly mer emulsio n 35 40 60 65 50 Terpene resin emulsio n 50 35 40 60 65

[00254] Effect Experiment

[00255] A method for evaluating single-yarn pull-out force property under high temperature and high humidity after hot-water aging:

[00256] a specific method included cutting a newly prepared test sample block of 20 cm*20 cm from the artificial turf and using 10 clamps to clamp innermost single grass yarns of the whole cluster of grass yarns respectively, where because the single grass yarn was located at the innermost position, it often had poor mechanical property due to the penetration problem of the adhesive, and was also the part most prone to falling off during later use, and the clamping positions were uniformly distributed in different regions of the test sample block; placing the sample block in a water bath at the temperature of (70±2)°C for 14 d, and after that, adjusting the temperature of the water bath to (50±2)°C and maintaining for (24±1) h, using a hand-held tensiometer to test the single-yarn pull-out force at the 10 points, and calculating the average value as the single-yarn pull-out force value under high temperature and high humidity after hot-water aging .

[00257] Table 7: Mechanical Property Test Data of Different Comparative Examples and Examples Test item Comparat ive Example 1 Comparat ive Example 2 Comparat ive Example 3 Comparat ive Example 4 Comparat ive Example 5 Comparat ive Example 6 Exam ple 1 Exam ple 2 Singleyarn pull-out force (N) under high temperat ure and high humidity after hot-water aging 2.1 6.5 3.2 3.9 5.5 6.1 11.9 14.0

[00258] It could be seen from the test data of Comparative Examples 1 -4 and Example 1 in Table 7 that when the adhesive composition of the present application is applied to the backing adhesive of artificial turf, the innermost single grass yarn still maintains excellent pull-out force property in a high-temperature and high-humidity environment after long-term hot-water aging, and that compared to currently used styrene-butadiene backing adhesive, polyurethane backing adhesive, and the backing adhesive technologies disclosed in patents 200780101243.2 and 201510491592.6, the property is obviously improved. As can be seen from the test data from Comparative Example 5 and Comparative Example 6, the functional emulsion and surfactant in the composition are indispensable, and their synergistic effect is crucial for improving property. In addition, as can be seen from the test data from Example 2, when a certain proportion of high-thermal-conductivity filler silicon carbide is added to the filler, heat can be quickly and timely transferred to the interior of the adhesive layer during curing of the backing adhesive, which is very helpful for improving the mechanical properties of the innermost grass yarn.

[00259] Table 8: Mechanical Property Test Data of Different Comparative Examples and Examples

[00260] Test item Comparati ve Example 7 Exampl e 3 Exampl e 1 Exampl e 4 Exampl e 5 Exampl e 6 Comparati ve Example 8 Exampl e 7 Singleyarn pullout force (N) under high temperatu re and high humidity after hot-water aging 5.3 8.2 11.9 11.2 9.1 7.9 6.4 8.7

[00261] It could be seen from the data of Examples and Comparative examples in Table 8 that the content of vinyl acetate structural units in the ethylene-vinyl acetate emulsion in the adhesive composition of the present application needs to be within a suitable range, and too low or too high content adversely affected the mechanical properties of the innermost single grass yarn in extreme environments. In addition, from the data of Example 3 and Example 7, it could be seen that the mechanical properties of the innermost single grass yarn can be improved to a certain extent after the matrix resin is modified by maleic anhydride.

[00262] Table 9 Mechanical Property Test Data of Different Comparative Examples and Examples Test item Example 8 Comparative Example 9 Example 9 Comparative Example 10 Single-yarn pullout force (N) under high temperature and high humidity after hot-water aging 10.4 6.9 10.5 6.3

[00263] It could be seen from the test data in Table 9 that the larger particle size of the emulsion affects the permeability of the whole adhesive, and further affects the property of the innermost single grass yarn.

[00264] Table 10: Mechanical Property Test Data of Different Comparative Examples and Examples Test item Comparat ive Example 11 Examp le 10 Examp le 11 Comparat ive Example 12 Comparat ive Example 13 Examp le 12 Examp le 13 Comparat ive Example 14 Singleyarn pull-out force (N) under high temperat ure and high humidity after hot-water aging 5.7 8.2 9.2 6.9 6.0 8.7 9.7 6.5

[00265] It could be seen from the test data in Table 10 that the solid content of the emulsion also affects the pull-out force property of the innermost single grass yarn, where the lower the solid content, the more water content in the composition, which affects the drying in the later stage and further affects the melt bonding; and the higher the solid content, the worse the permeability, which ultimately produces an adverse effect on the property, thus a suitable range of solid content is also required.

[00266] Table 11: Mechanical Property Test Data of Different Comparative Examples and Examples Test item Exam ple 14 Exam ple 15 Exam ple 16 Exam ple 17 Exam ple 18 Exam ple 19 Exam ple 20 Exam ple 21 Exam ple 22 Exam ple 23 Singleyarn pull-out force (N) under high temperat ure and high humidit y after hot-water aging 11.0 10.4 8.0 11.2 10.9 8.9 8.0 11.5 11.5 9.1

[00267] It could be seen from the data of Examples 16-19 in Table 11 that both the ethylene vinyl acetate emulsion and the functional emulsion need to be in a suitable ratio range, where the too high content of the ethylene-vinyl acetate emulsion and the too low content of the functional emulsion in the composition affect the penetration and wetting, while the too low content of the ethylene-vinyl acetate emulsion and the too high content of the functional emulsion affect the film formation of the whole adhesive layer, and the lack of sufficient ethylene segments and polar vinyl acetate further affects adhesion to the grass yarn interface. From the test data of Examples 14-15 and 20-23, it could be seen that the type and content of the surfactant also have a greater effect on the property, where when used in combination, the anionic and nonionic surfactants can achieve good penetration at a lower content to improve the pull-out force property of the innermost single grass yarn in the extreme environments.

[00268] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not to be limited to the embodiments shown herein, but complies with the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An adhesive composition for artificial turf, comprising following components by mass percentages:10-50% of an ethylene-vinyl acetate copolymer emulsion or a modified ethylene-vinyl acetate copolymer emulsion with an average particle size of latex particles of less than 3 pm, wherein a solid content of the ethylene-vinyl acetate copolymer emulsion is 40-60%;5-40% of a functional resin emulsion with an average particle size of latex particles of less than 3 pm, wherein a solid content of the functional resin emulsion is 40-60%;0.1-10% of a surfactant; and0-80% of an inorganic filler;wherein a matrix resin ethylene-vinyl acetate copolymer in the ethylene-vinyl acetate copolymer emulsion comprises 10-60% of vinyl acetate structural units by mass percentage; anda matrix resin modified ethylene-vinyl acetate copolymer in the modified ethylene-vinyl acetate copolymer emulsion comprises by mass percentages, 10-60% of the vinyl acetate structural units and 0.1-10% of modified monomer structural units, and modified monomers comprise one or more selected from the group consisting of methacrylic acid, acrylic acid, glycidyl methacrylate and maleic anhydride.

2. The adhesive composition for artificial turf according to claim 1, wherein the average particle size of latex particles in the ethylene-vinyl acetate copolymer emulsion is 0.05-2 pm.

3. The adhesive composition for artificial turf according to claim 1, wherein the functional resin emulsion is one or more selected from the group consisting of a terpene resin emulsion, a rosin resin emulsion and a petroleum resin emulsion.

4. The adhesive composition for artificial turf according to claim 1, wherein the average particle size of latex particles in the functional resin emulsion is 0.05-2 pm.

5. The adhesive composition for artificial turf according to claim 1, wherein the surfactant is one or more selected from the group consisting of an anionic surfactant, a cationic surfactant and a nonionic surfactant.

6. The adhesive composition for artificial turf according to claim 1, wherein the anionic surfactant comprises one or more selected from the group consisting of potassium rosinate, potassium oleate, sodium polyacrylate, fatty alcohol polyoxyethylene ether sulfate, sodium a-alkenyl sulfonate, sodium dodecyl sulfate and sodium dodecyl benzene sulfonate; the cationicsurfactant comprises one or more selected from the group consisting of dodecyl ammonium chloride, cetyltrimethyl ammonium bromide and cetylpyridinium quaternary ammonium salt; and the nonionic surfactant comprises one or more selected from the group consisting of polyoxyethylene ether, castor oil polyoxyethylene ether, polyethylene glycol, Span 80, Tween 80 and Tween 20.

7. The adhesive composition for artificial turf according to claim 1, wherein the inorganic filler comprises one or more selected from the group consisting of calcium carbonate, mica, barium sulfate, aluminum hydroxide, magnesium hydroxide, talcum powder, wollastonite, glass microbeads, silicon dioxide and silicon carbide.

8. A method for preparing an adhesive composition for artificial turf, comprising following steps:(1) weighing individual raw materials according to the adhesive composition for artificial turf according to any one of claims 1-7; and(2) mixing and stirring the ethylene-vinyl acetate copolymer emulsion, the functional resin emulsion, the surfactant and the inorganic filler to obtain the adhesive composition for artificial turf.

9. An artificial turf, comprising the adhesive composition for artificial turf according to any one of claims 1-7, artificial grass yarns and a backing fabric, wherein the artificial grass yarns are tufted on the backing fabric, and a back coated surface of the backing fabric is coated with the adhesive composition for artificial turf.

10. A method for preparing artificial turf, comprising following steps:1) melt extruding polyethylene and / or polypropylene, drawing and spinning, and heat setting to obtain artificial grass yarns;2) tufting the obtained artificial grass yarns on the backing fabric to obtain a semi-finished product of the artificial turf; and3) uniformly coating the adhesive composition for artificial turf according to any one of claims 1-7 on a back coated surface of the obtained semi-finished product of the artificial turf, and drying to obtain the artificial turf.