CN113913146B

CN113913146B - Adhesive and preparation method and application thereof

Info

Publication number: CN113913146B
Application number: CN202010646863.1A
Authority: CN
Inventors: 周天文; 刘姗; 王海梅; 晋云全
Original assignee: Wanhua Chemical Group Co Ltd
Current assignee: Wanhua Chemical Group Co Ltd
Priority date: 2020-07-07
Filing date: 2020-07-07
Publication date: 2023-03-28
Anticipated expiration: 2040-07-07
Also published as: CN113913146A

Abstract

The invention discloses an adhesive, which comprises a component A and a component B, wherein the component A comprises: 20-70 parts of aqueous polyurethane dispersion; 20-70 parts of natural latex; 10-50 parts of ethylene-vinyl acetate copolymer emulsion; wherein the total of the aqueous polyurethane dispersion, the natural latex and the ethylene-vinyl acetate copolymer emulsion is 100 parts by weight, and the component B comprises: and the curing agent accounts for 1-10 parts by weight of the total weight of the aqueous polyurethane dispersion, the natural latex and the ethylene-vinyl acetate copolymer emulsion. By introducing the waterborne polyurethane emulsion and the ethylene-vinyl acetate emulsion, the adhesive provided by the invention has the advantages that the initial strength, the later strength and the water resistance are obviously improved, and the adhesive can meet the bonding requirements of different vamp substrates.

Description

Adhesive and preparation method and application thereof

Technical Field

The invention belongs to the technical field of adhesives, and particularly relates to a water-based vulcanized adhesive as well as a preparation method and application thereof.

Background

As daily necessities, the global footwear industry has huge and stably increased scale, and the global footwear yield is basically maintained to be more than 220 hundred million double in 2013-2017 from the aspect of footwear yield scale. In 2017, the global shoe yield reaches 235 hundred million pairs, and the yield is increased by about 2 percent. In 2018, the global shoe yield reaches about 237 hundred million pairs. And (3) displaying data: global footwear production is primarily focused on asia, which accounts for 86.8% of the total global footwear production and 60% of chinese footwear production. China is the biggest shoe manufacturing base in the world and is also the biggest export country of shoes in the world. After the shoe making industry in China is rapidly developed, the traditional development mode of pursuing quantity expansion and low price competition cannot occupy advantages in the international market, and under the large background of economic transformation, the improvement of the technical level and the improvement of the product quality are inevitable trends of future development of the shoe making industry.

The vulcanized rubber for vulcanizing shoes in the prior art mainly comprises natural latex, sulfur and a vulcanization accelerator. The method mainly comprises the steps of coating glue on the upper, the surrounding strips and the vamp, drying through a drying channel, then pressing, and finally vulcanizing in a vulcanizing tank. The vulcanization temperature is 100-130 ℃. The vulcanization pressure is 2-4 atmospheres. The vulcanization time is 1-3 hours. The vulcanized rubber has low bonding strength with the shoe upper, and has low bonding force with some substrates, such as PU leather, PVC leather, genuine leather and the like, so that the phenomenon of rubber separation often occurs. Can not meet the requirement of diversification of the prior vamp.

Chinese patent CN106987226A discloses a natural latex composite waterborne polyurethane adhesive and a preparation method and application thereof. The surface grafting reaction of the coupling agent containing double bond functional groups on the nano silicon dioxide is taken as a crosslinking point, and the crosslinking point is added into the natural latex composite polyurethane containing the crosslinking agent. The adhesive is applied to bonding between leathers, between leathers and rubber and the like.

Chinese patent CN106478890A discloses a preparation method of a water-based polyurethane-polyvinyl acetate hybrid emulsion, which comprises the steps of firstly preparing a double-bond polyurethane prepolymer monomer, then polymerizing by using a seed emulsion polymerization method, wherein the polyurethane prepolymer monomer and vinyl acetate form a mixed reaction system, and the polyurethane prepolymer exists in the reaction system in a monomer form and is subjected to copolymerization reaction with the vinyl acetate, so that the polyurethane monomer can be grafted to a macromolecular chain of the polyvinyl acetate, and the flexibility of the polyvinyl acetate molecular chain is greatly improved. However, since the comonomer is introduced into the molecular chain, the adhesive property is reduced, and the process operation is extremely complex, which brings inconvenience to the subsequent production.

In conclusion, how to solve the technical difficulties that the prior adhesive has narrow adaptive surface to the base material, low bonding strength and poor water resistance is a breakthrough in the field is urgently needed.

Disclosure of Invention

In view of the above problems in the prior art, the present invention provides an adhesive. The defects of narrow adaptive surface of the vulcanized rubber to the base material, low bonding strength, poor water resistance and the like in the prior art are overcome, the applicability of the adhesive to different application base materials can be improved, the strength, the heat resistance and the water washing resistance are obviously improved, the production process is simple, the adhesive is basically consistent with the existing process, and the adhesive can be replaced and used.

In order to achieve the purpose, the invention adopts the following technical scheme:

in one aspect of the invention, an adhesive is provided comprising an a-side and a B-side, wherein,

the component A comprises:

20 to 70 parts by weight, preferably 25 to 60 parts by weight, more preferably 25 to 50 parts by weight, such as 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight, 55 parts by weight, 65 parts by weight, or the like, of the aqueous polyurethane dispersion;

20 to 70 parts by weight, preferably 25 to 60 parts by weight, for example 30 parts by weight, 35 parts by weight, 40 parts by weight, 45 parts by weight, 50 parts by weight, 55 parts by weight or 65 parts by weight of natural rubber latex;

10 to 50 parts by weight, preferably 15 to 40 parts by weight, for example 20 parts by weight, 25 parts by weight, 30 parts by weight, 35 parts by weight or 45 parts by weight of the ethylene-vinyl acetate copolymer emulsion;

wherein the total of the aqueous polyurethane dispersion, the natural latex and the ethylene-vinyl acetate copolymer emulsion is 100 parts by weight,

the component B comprises:

and a curing agent in an amount of 1 to 10 parts by weight, preferably 3 to 7 parts by weight, for example, 2 parts by weight, 4 parts by weight, 5 parts by weight, 6 parts by weight, 8 parts by weight, 9 parts by weight, or the like, based on the total weight of the aqueous polyurethane dispersion, natural latex, and ethylene-vinyl acetate copolymer emulsion.

In a specific embodiment of the present invention, the a component further comprises one or more of the following, based on the total weight of the aqueous polyurethane dispersion, natural latex, and ethylene-vinyl acetate copolymer emulsion:

0.02 to 1 part by weight of a defoaming agent, preferably 0.05 to 0.1 part by weight;

0.3 to 3 parts by weight of a surfactant, preferably 0.5 to 2 parts by weight;

0.05 to 1 part by weight of a thickener, preferably 0.1 to 0.8 part by weight; and

0.05 to 1 part by weight of a filler, preferably 0.1 to 0.5 part by weight.

In a specific embodiment of the present invention, the aqueous polyurethane dispersion is obtained by neutralizing and dispersing in water a prepolymer obtained by polymerizing components including diisocyanate, polyol and hydrophilic compound. As the diisocyanate, for example, aromatic diisocyanate and/or aliphatic diisocyanate can be used. Examples of the polyol include polyether polyol, polyester polyol and polyether polyester hybrid polyol. As the hydrophilic compound, for example, sulfonic acid type hydrophilic compounds and carboxylic acid type hydrophilic compounds can be used.

In a preferred embodiment of the invention, the aqueous polyurethane dispersion has a solids content of 45 to 55%, such as 49 to 51% or 48 to 52%, etc.; a pH of 6 to 9, e.g. 7 or 8; a viscosity of 100 to 4000cps, e.g., 500cps, 1000cps, 1500cps, 2000cps, 2500cps, 3000cps, 3500cps, or the like; and/or a particle size of 150-250nm, for example 170-205nm.

Specifically, the aqueous polyurethane dispersion preferably uses one or more of Adwel 1630B, adwel 1637, and Adwel 1639 from wawa chemical group, ltd.

In a specific embodiment of the present invention, the natural latex is a concentrated natural latex, which is obtained by concentrating sap of hevea brasiliensis by centrifugation or evaporation.

In a preferred embodiment of the invention, the natural rubber latex has a solids content of 55-65%, preferably 58-62%, such as 60-62% or 59-62%, etc.; a pH of 9 to 12, for example 10 or 11; and/or a viscosity of 100-2000cps, such as 200cps, 300cps, 500cps, 1000cps, or 1500cps, and the like.

Specifically, the natural rubber latex preferably uses TVRTEX and/or THAIHUATEX of the yellow spring hair from the Hexagon chemical industry.

In a specific embodiment of the present invention, the ethylene-vinyl acetate copolymer emulsion is a polymer emulsion obtained by copolymerizing vinyl acetate and an ethylene monomer as basic raw materials by an emulsion polymerization method.

In a preferred embodiment of the present invention, the viscosity of the ethylene-vinyl acetate copolymer emulsion is 4000 to 12000cps, for example, 5000cps, 6000cps, 7000cps, 8000cps, 9000cps, 10000cps, 11000cps, etc.; pH 4-6, e.g., 5; and/or a solids content of 54-57%, such as 55-56%, etc.

Specifically, the ethylene-vinyl acetate copolymer emulsion preferably uses one or more of DA102 of the Dalian chemical industry and EP645 and EP708 of Wake China Co.

In a particular embodiment of the invention, the thickener is a hydrophobically associative polyurethane thickener. Specifically, one or more of U604, U601, U300 and U902 of Wanhua chemical group, inc. are preferably used as the thickener.

In a particular embodiment of the invention, the surfactant molecular structure has an amphiphilic nature: one end is a hydrophilic group, and the other end is a hydrophobic group; the hydrophilic group is preferably a polar group, more preferably a carboxylic acid group, a sulfonic acid group, a sulfuric acid group, an amino group, an amine group or a salt thereof, a hydroxyl group, an amide group or an ether bond; the hydrophobic group is preferably a non-polar hydrocarbon chain, more preferably a non-polar hydrocarbon chain containing 8 to 25 carbon atoms. Specifically, the surfactant is preferably one or more of peregal, tween 20 and sodium dodecylbenzenesulfonate from affliction chemical limited, guangzhou city.

In a specific embodiment of the present invention, the filler is nanosilica, preferably one or more of fumed nanosilica, wet nanosilica and sol-gel nanosilica. Specifically, one or more of A200, A300 and R202 of Woodbend China Limited are preferably used as the filler.

In a specific embodiment of the present invention, the defoaming agent is a silicone-based defoaming agent. Specifically, the antifoaming agent is preferably one or more of BYK-020, BYK-022 and BYK-024 from Hua Ling chemical products, inc. of Qingdao.

In a particular embodiment of the invention, as the B-component, the curing agent is a water-dispersible isocyanate curing agent, preferably having an NCO content of 10-25%, more preferably 18-22%, such as 18-19% or 21-22%, and the like. Specifically, one or more of Aquolin 161, aquolin163 and Aquolin166 of wawa chemical group ltd are preferably used as the curing agent.

By introducing the waterborne polyurethane emulsion and the ethylene-vinyl acetate emulsion, the adhesive provided by the invention has the advantages that the initial strength, the later strength and the water resistance are obviously improved, and the adhesive can meet the bonding requirements of different vamp substrates. And the process conditions are the same as the prior process conditions, and the simple glue replacement can be directly carried out, so that a good bonding effect can be achieved.

Specifically, by introducing natural rubber latex, the natural rubber latex and double bonds in the foxing and the sole are subjected to vulcanization crosslinking reaction, so that the bonding strength of the foxing and the sole is ensured. By introducing the ethylene-vinyl acetate copolymer emulsion containing carboxyl, the reaction with ammonia water in natural latex can be realized, the low ammonia value residue of a glue system is ensured, sufficient operable time is provided after the water-based curing agent is added, partial crosslinking exists, and excellent water resistance is ensured. By introducing the aqueous polyurethane dispersion, the polyurethane has higher cohesive strength, can build strength with vamps made of different materials, and reacts with the aqueous curing agent, so that the adhesive has excellent heat resistance and washing resistance. Meanwhile, the three components are introduced, the respective characteristics of the three components are kept, and the three components have obvious synergistic effect and react with a water-based curing agent to form an interpenetrating network structure through a vulcanization reaction with the surrounding strip. Therefore, the adhesive has excellent strength, heat resistance and water washing resistance.

In another aspect of the present invention, there is provided a method for preparing the adhesive as described above, wherein the adhesive is obtained by mixing the raw materials uniformly in amounts to obtain a component a, mixing the component a with a component B in amounts to adjust the viscosity to 1000-4000cps, preferably 1500-3000cps, for example 2000cps or 2500cps, etc.

In a specific embodiment of the present invention, the preparation method of the adhesive comprises the following steps:

1) Mixing and stirring the aqueous polyurethane dispersion, the natural latex, the ethylene-vinyl acetate copolymer emulsion, the defoaming agent and the surfactant to obtain a mixture 1; preferably the stirring time is from 10 to 30 minutes, more preferably from 15 to 25 minutes; preferably the stirring speed is from 100 to 600 revolutions per minute, more preferably from 200 to 400 revolutions per minute;

2) Mixing and stirring the mixture 1 obtained in the step 1) with a filler and a thickening agent to obtain a mixture 2; preferably the stirring time is 15-45 minutes, more preferably 20-30 minutes; preferably the stirring speed is from 200 to 1000 rpm, more preferably from 400 to 600 rpm;

3) Mixing the mixture 2 obtained in the step 2) with a curing agent and stirring, and adjusting the viscosity to 1000-4000cps, preferably 1500-3000cps to obtain the adhesive; preferably the stirring time is from 10 to 30 minutes, more preferably from 15 to 25 minutes; preferably, the stirring speed is from 100 to 600 revolutions per minute, more preferably from 200 to 400 revolutions per minute.

In a further aspect of the invention there is provided the use of an adhesive as described above or an adhesive made according to the method of preparation as described above in the manufacture of shoes.

Compared with the prior art, the beneficial effects of the invention are mainly embodied in the following aspects:

1) The adhesive is compounded by adopting natural latex, aqueous polyurethane dispersoid and ethylene-vinyl acetate polymer, thereby improving the applicability of the adhesive to different application base materials.

2) The adhesive is compounded by adopting natural latex, aqueous polyurethane dispersoid and ethylene-vinyl acetate polymer, and compared with the adhesive in the prior art, the strength, the heat resistance and the water washing resistance of the adhesive are obviously improved.

3) The invention has simple production process, is basically consistent with the prior art, and can be replaced for use.

Detailed Description

The process provided by the present invention is described in further detail below, but the present invention is not limited thereto.

Raw materials

1. Aqueous polyurethane dispersion: adwel 1637 (solid content 49-51%, pH 6-9, viscosity 1000-4000cps, particle size 170-205 nm), adwel 1630B (solid content 49-51%, pH 6-9, viscosity 500-4000cps, particle size 170-205 nm) and Adwel 1639 (solid content 48-52%, pH 6-9, viscosity 100-2000cps, particle size 170-205 nm), manufactured by Vanhua chemical group, inc.;

2. natural latex: TVRTEX (solid content 60-62%, pH 10-12, viscosity 100-1000 cps) and three-tree brand THAIHUATEX (solid content 59-62%, pH 10-12, viscosity 100-2000 cps), changzhou modern chemical industry;

3. ethylene vinyl acetate emulsion: DA102 (solid content 55-56%, pH 4-6, viscosity 6000-11000 cps), and is suitable for industrial production; EP645 (solid content 55-56%, pH 4-6, viscosity 5000-10000 cps) and EP708 (solid content 55-56%, pH 4-6, viscosity 5000-11000 cps), manufactured by Wake China Co., ltd;

4. thickening agent: u604, U601, U300 and U902, produced by Vanhua chemical group, inc.;

5. surfactant (B): peregal, tween 20 and sodium dodecylbenzenesulfonate, yuxiang chemical industries, inc;

6. filler silica: a200, A300 and R202, wiegingdebridement China Limited;

7. curing agent: aquolin 161 (NCO content 18-19%), aquolin163 (NCO content 18-19%) and Aquolin166 (NCO content 21-22%), manufactured by Wanhua chemical group GmbH;

8. defoaming agent: BYK-020, BYK-022 and BYK-024, produced by Qingdao Hualing chemical products, inc.;

9. sulfur, shandong Xinlai New Material science and technology, inc.;

10. promoter DM, doujia leaf Biotechnology Ltd.

Test method

(1) Peel Strength test

1) Initial peel strength test:

base material and pretreatment before use:

1) 9 fresh circumference strips (10 cm long x 2cm wide) which are treated with gasoline glue before use;

2) 3 pieces of PU synthetic leather (10 cm long is multiplied by 2cm wide) are wiped by butanone before use;

3) 3 pieces of PVC synthetic leather (10 cm long is multiplied by 2cm wide) are wiped by butanone before use;

4) 3 canvases (10 cm long. Times.2 cm wide) were left untreated.

The operation method takes the example of pasting PU leather on the foxing as follows:

brushing the adhesive on the surfaces of the foxing and the PU leather respectively by using a brush, placing the foxing and the PU leather into a 70 ℃ oven for heat activation for 4 minutes, taking out and pressing for 10 seconds, setting the gage pressure at 4bar, and immediately taking out and testing the peel strength after pressing. And clamping the test piece on an upper clamp and a lower clamp of a tensile machine, setting the moving speed of the clamps to be 200mm/min, repeatedly testing 3 test pieces, and reading the average peeling strength value.

2) And (3) later-stage peel strength test: the manufacturing method of the test piece is the same as the initial strength, after the test piece is pressed, the test piece is placed in a 120 ℃ oven for two hours, the test piece is taken out and placed for 24 hours at 25 ℃, then a tensile machine is used for testing the later-stage peeling strength, the moving speed of a clamp is 200mm/min, 3 test pieces are tested repeatedly, and the average value is taken.

(2) Heat resistance test

And (3) heat resistance test: the test piece was produced in the same manner as described for the later strength in part (1), and the produced test piece was left at 25 ℃ for 24 hours and then tested. The test method is that the load is 500g and is placed in an oven at 80 ℃, the rubber is taken out for 30 minutes to measure the rubber-stripping length, and the heat resistance is represented by the length value. The shorter the length, the better the heat resistance.

(3) Water resistance test

The test piece was made as described for the later strength in part (1), and the prepared test piece was left to stand at 25 ℃ for 24 hours and then was subjected to a test. The test piece is placed in water with the temperature of 50 ℃, soaked for 8 hours and taken out to test the peel strength. The greater the peel strength after soaking, the better the water wash resistance.

(4) Viscosity measurement of adhesive:

the viscosity was determined by reference to GB/T2794-2013 (Brookfield LV,63#/12 rpm).

Examples

Example 1

The component A comprises:

and B component:

curing agent Aquolin 161 7 weight parts

The adhesive of the embodiment is prepared by the following steps:

1) Mixing and stirring aqueous polyurethane dispersion Adwel 1637 (60 g), natural latex THAIHUATEX (25 g), ethylene-vinyl acetate copolymer emulsion DA102 (15 g), defoaming agent BYK024 (0.06 g) and surfactant Tween 20 (1 g) for 20 minutes at a stirring speed of 300 revolutions per minute to obtain a mixture 1; mixing and stirring the obtained mixture 1, a filler A200 (0.4 g) and a thickening agent U604 (0.3 g) for 25 minutes at a stirring speed of 500 revolutions per minute to obtain a mixture 2;

2) The resulting mixture 2 was mixed with curative Aquolin 161 (7 g) and stirred for 20 minutes at 300 rpm to adjust the viscosity to 2500cps.

The starting materials for examples 2-9 and their formulations are shown in Table 1 below, and were prepared in a similar manner to example 1. The values in table 1 are parts by weight.

Table 1: the starting materials of examples 2-9 and their formulations

Wherein for examples 2-9 above, adwel 1637 was used for the aqueous polyurethane dispersion, except Adwel 1630B was used for example 8 and Adwel 1639 was used for example 9; three trees brand THAIHUATEX was used for the natural rubber latex except that the yellow spring TVRTEX was used in example 8; the ethylene vinyl acetate emulsions used DA102, except that EP645 was used for example 7 and EP708 was used for example 9.

Comparative example 1

The comparative adhesive was prepared by the following steps:

natural latex THAIHUATEX (50 g), aqueous polyurethane dispersion Adwel 1637 (50 g), defoamer BYK024 (0.06 g) and surfactant Tween 20 (1 g) were mixed and stirred for 20 minutes at a stirring speed of 300 rpm to give mixture 1. The mixture 1 obtained is mixed and stirred with sulphur (3 g), accelerator DM (1 g) and thickener U604 (0.6 g) for 45 minutes at a speed of 500 revolutions per minute. The viscosity was adjusted to 2500cps.

Comparative example 2

The comparative adhesive was prepared by the following steps:

1) Aqueous polyurethane dispersion Adwel 1637 (50 g), ethylene-vinyl acetate copolymer DA102 (50 g), defoamer BYK024 (0.06 g), and surfactant tween 20 (1 g) were mixed and stirred for 20 minutes at a stirring speed of 300 rpm to give mixture 1. The resulting mixture 1 was mixed with filler A200 (0.4 g) and thickener U604 (0.2 g) and stirred for 25 minutes at a stirring speed of 500 rpm to give mixture 2.

2) The mixture 2 obtained is mixed with a curing agent Aquolin 161 (5 g) and stirred for 20 minutes at a stirring speed of 300 revolutions per minute. The viscosity was adjusted to 2500cps.

Comparative example 3

The comparative adhesive was prepared by the following steps:

1) Ethylene-vinyl acetate resin DA102 (50 g), natural latex THAIHUATEX (50 g), defoamer BYK024 (0.06 g) and surfactant Tween 20 (1 g) were mixed and stirred for 20 minutes at a stirring speed of 300 revolutions/minute to give mixture 1. The resulting mixture 1 was mixed with filler A200 (0.4 g) and thickener U604 (0.3 g) and stirred for 25 minutes at a stirring speed of 500 rpm to give mixture 2.

2) The resulting mixture 2 was mixed with curing agent Aquolin 161 (5 g) and stirred for 20 minutes at a speed of 300 rpm. The viscosity was adjusted to 2500cps.

Comparative example 4

The comparative adhesive was prepared by the following steps:

natural latex THAIHUATEX (100 g), defoamer BYK024 (0.06 g) and surfactant Tween 20 (1 g) were mixed and stirred for 20 minutes at a stirring speed of 300 rpm to give a mixture. The resulting mixture was mixed with sulphur (3 g), accelerator DM (1 g) and thickener U604 (0.6 g) and stirred for 45 minutes at 500 rpm. The viscosity was adjusted to 2500cps.

The adhesives obtained according to the above examples 1 to 9 and comparative examples 1 to 4 were subjected to the peel strength, heat resistance and washing resistance tests as described above, and the results were as follows:

table 2 peel strength test data

From table 2 peel strength data: compared with comparative examples 1 to 4, the initial strength and the later strength of examples 1 to 9 are obviously improved, and the bonding requirements of vamps made of different materials can be met. The invention can obviously improve the peeling strength of the adhesive to different base materials through the synergistic effect of the natural latex, the aqueous polyurethane dispersion and the ethylene-vinyl acetate copolymer emulsion.

Table 3 heat resistance test data

From the heat resistance data in table 3, the heat resistance of examples 1 to 9 is superior to that of comparative examples 1 to 4 in heat resistance, and can meet the heat resistance requirements of vamps made of different materials. The invention can obviously improve the heat resistance of the adhesive to different base materials through the synergistic effect of the natural latex, the aqueous polyurethane dispersion and the ethylene-vinyl acetate copolymer emulsion.

Table 4 water wash resistance test data

From the water-fast data in table 4, the examples 1-9 are significantly better in water-fast than the comparative examples 1-4, and can satisfy the water-fast requirements of vamps with different materials. The water washing resistance of the adhesive to different base materials can be obviously improved through the synergistic effect of the natural latex, the aqueous polyurethane dispersion and the ethylene-vinyl acetate copolymer emulsion.

Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims.

Claims

1. An adhesive comprising an A-side and a B-side, wherein,

the component A consists of the following components:

20-70 parts of aqueous polyurethane dispersion;

20-70 parts of natural latex;

10-50 parts of ethylene-vinyl acetate copolymer emulsion;

0.02-1 part by weight of defoaming agent;

0.3-3 parts by weight of a surfactant;

0.05-1 part of thickening agent; and

0.05-1 part by weight of a filler;

the component B comprises:

and the curing agent accounts for 1-10 parts by weight of the total weight of the aqueous polyurethane dispersion, the natural latex and the ethylene-vinyl acetate copolymer emulsion.

2. The adhesive of claim 1,

25-60 parts by weight of the aqueous polyurethane dispersion;

25-60 parts by weight of natural latex;

15-40 parts of ethylene-vinyl acetate copolymer emulsion;

0.05-0.1 part by weight of defoaming agent;

0.5-2 parts by weight of surfactant;

0.1 to 0.8 weight part of thickening agent;

0.1 to 0.5 weight part of filler; and

the curing agent is 3-7 parts by weight.

3. The adhesive of claim 1, wherein the aqueous polyurethane dispersion has a solids content of 45-55%; the pH is 6-9; the viscosity is 100-4000cps; and/or the particle size is 150-250nm.

4. The adhesive of claim 1 wherein the natural rubber latex is a concentrated natural rubber latex having a solids content of 55-65%; the pH value is 9-12; and/or a viscosity of 100 to 2000cps.

5. The adhesive of claim 4 wherein the natural rubber latex has a solids content of 58-62%.

6. The adhesive of claim 1 wherein the ethylene-vinyl acetate copolymer emulsion has a viscosity of 4000-12000cps; the pH is 4-6; and/or a solids content of 54-57%.

7. The adhesive of any one of claims 1-6,

the thickening agent is hydrophobic association type polyurethane thickening agent;

the molecular structure of the surfactant has amphipathy: one end is a hydrophilic group, and the other end is a hydrophobic group;

the filler is nano silicon dioxide;

the defoaming agent is an organic silicon defoaming agent.

8. The adhesive of claim 7,

the hydrophilic group is a polar group; the hydrophobic group is a non-polar hydrocarbon chain;

the filler is one or more of gas-phase nano-silica, wet-process nano-silica and sol-gel nano-silica.

9. The adhesive of claim 8,

the hydrophilic group is carboxylic acid group, sulfonic group, sulfuric acid group, amino group or their salts, hydroxyl group, amide group or ether bond; the hydrophobic group is a non-polar hydrocarbon chain containing 8 to 25 carbon atoms.

10. The adhesive of any one of claims 1-6 wherein the curing agent is a water dispersible isocyanate curing agent.

11. The adhesive of claim 10 wherein the water-dispersible isocyanate curing agent has an NCO content of 10-25%.

12. The adhesive of claim 11 wherein the water-dispersible isocyanate curing agent has an NCO content of 18-22%.

13. The method for preparing the adhesive according to any one of claims 1 to 12, wherein the adhesive is obtained by uniformly mixing the raw materials according to the amount to obtain the component A, mixing the component A with the component B according to the amount to adjust the viscosity to 1000 to 4000 cps.

14. The method of claim 13, wherein the adhesive is obtained by adjusting the viscosity to 1500-3000 cps.

15. The method of manufacturing according to claim 13 or 14, comprising the steps of:

1) Mixing and stirring the aqueous polyurethane dispersion, the natural latex, the ethylene-vinyl acetate copolymer emulsion, the defoaming agent and the surfactant to obtain a mixture 1;

2) Mixing and stirring the mixture 1 obtained in the step 1) with a filler and a thickening agent to obtain a mixture 2;

3) Mixing the mixture 2 obtained in the step 2) with a curing agent, stirring, and adjusting the viscosity to 1000-4000cps to obtain the adhesive.

16. The production method according to claim 15, wherein:

in the step 1), the stirring time is 10-30 minutes; the stirring speed is 100-600 revolutions per minute;

in the step 2), the stirring time is 15-45 minutes; the stirring speed is 200-1000 r/min;

in the step 3), adjusting the viscosity to 1500-3000cps to obtain the adhesive; the stirring time is 10 to 30 minutes; the stirring speed is 100-600 r/min.

17. The production method according to claim 16, wherein:

in the step 1), the stirring time is 15-25 minutes; the stirring speed is 200-400 r/min;

in the step 2), the stirring time is 20-30 minutes; the stirring speed is 400-600 revolutions per minute;

in the step 3), the stirring time is 15-25 minutes; the stirring speed is 200-400 rpm.

18. Use of the adhesive according to any one of claims 1 to 12 or the adhesive produced according to the production method of any one of claims 13 to 17 for the production of shoes.