Direct-vat warm-mixing high-viscosity modifier and preparation method thereof

Abstract

The invention belongs to the technical field of road building materials, and particularly relates to a direct-vat warm-mixing high-viscosity modifier and a preparation method thereof, and the direct-vat warm-mixing high-viscosity modifier comprises the following components in parts by weight: 40-60 parts of an SBS modifier, 10-20 parts of rubber powder, 10-25 parts of a multifunctional warm-mixing agent and 10-15 parts of filling oil. The multifunctional warm mixing agent comprises the following components in parts by mass: 100 parts of polyethylene wax, 3-5 parts of low-density polyethylene, 0.2 part of a nucleating agent and 2-4 parts of a nonionic surfactant. According to the invention, the high-viscosity modification of the asphalt mixture can be realized in the production process of the asphalt mixture, the high and low temperature, water damage resistance and fatigue performance of the asphalt pavement can be effectively improved, the production temperature of the asphalt mixture can be effectively reduced, the emission of asphalt flue gas can be reduced, and the asphalt mixture is more energy-saving and environment-friendly. And the preparation method is simple, low in production cost and suitable for large-scale popularization and application.

Description

Technical Field

[0001] The invention belongs to the technical field of road construction materials, and in particular relates to a direct-cast warm-mix high-viscosity modifier and a preparation method thereof. Background Art

[0002] Different from traditional wet modified asphalt, direct-injection modification technology puts the modifier directly into the asphalt mixture mixing pot and completes the modification process during the production process. It has the advantages of convenient transportation and use, stable performance, etc. It avoids the segregation of modified asphalt during transportation and storage, and can also reduce costs. It has broad application prospects.

[0003] The current high-viscosity modification technology, whether wet or dry, is mainly based on SBS, which makes this series of products generally have the following shortcomings during use: 1) Due to the high viscosity of modified asphalt, the mixing and compaction temperature of the mixture during construction is greatly increased, the energy consumption is large, and the emission of smoke and dust during construction is large, which poses a great health hazard to construction site personnel; 2) A higher temperature is required during construction, and high requirements are placed on construction equipment and environment. It is not suitable for construction in winter or at low temperatures, and the construction efficiency is low; 3) The characteristics of the ultra-thin cover technology itself further increase the difficulty of construction, that is, the thin paving thickness and fast cooling speed can easily cause segregation of the mixture and insufficient actual paving density. This is also a problem that construction units generally report that the construction quality is difficult to control.

[0004] Therefore, it is necessary to develop a direct-injection warm-mix high-viscosity modifier to solve the above problems. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a direct-cast warm-mix high-viscosity modifier and a preparation method thereof, so as to solve the problems of high construction temperature, large smoke emission and difficult-to-control construction quality of SBS high-viscosity modified asphalt in the prior art. The asphalt mixture mixed with this additive can have the advantages of energy saving and environmental protection of traditional warm-mix asphalt mixture and good road performance of modified asphalt mixture, while making up for the shortcomings of the two, and is an ideal green, low-carbon asphalt pavement material. This warm-mix-modification technology is suitable for the construction and maintenance of long and large tunnel engineering pavements, municipal pavements, pavements in cold areas, ultra-thin road surface layers and any hot-mix asphalt pavement, and has a very broad application prospect.

[0006] The present invention provides a direct-cast warm-mix high-viscosity modifier, wherein the components and their weight proportions include: 40-60 parts of SBS modifier, 10-20 parts of rubber powder, 10-25 parts of multifunctional warm-mix agent, and 10-15 parts of filler oil;

[0007] The multifunctional warm mix agent comprises, by mass fraction, 100 parts of polyethylene wax, 3 to 5 parts of low-density polyethylene, 0.2 parts of nucleating agent, and 2 to 4 parts of nonionic surfactant.

[0008] Furthermore, the SBS modifier is a styrene-butadiene-styrene block copolymer, and the block ratio (mass ratio) of the polystyrene segment to the polybutadiene segment is 3:7.

[0009] Furthermore, the rubber powder is activated rubber powder obtained by desulfurization and activation of waste tire rubber powder, and the mesh number is ≥40 meshes.

[0010] Furthermore, the filler oil is cycloparaffinic oil, and the CN value is >40%.

[0011] Furthermore, the nucleating agent is a sorbitol nucleating agent.

[0012] Furthermore, the nonionic surfactant is one or more of diethanolamine stearate, glyceryl monostearate or polyethylene glycol stearate.

[0013] The present invention also provides a method for preparing a direct-injection warm-mix high-viscosity modifier, which comprises the following steps:

[0014] (1) Preparation of a multifunctional warm-mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 minutes; then add a nucleating agent and a non-ionic surfactant, and continue stirring for 30-40 minutes; after cooling, grind the mixture into powder to obtain a multifunctional warm-mix agent.

[0015] (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and the multifunctional warm mix agent and mix evenly.

[0016] (3) melt-granulating the mixture in step (2) using a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

[0017] Furthermore, in step (1), the stirring rate is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

[0018] Furthermore, during the granulation process of the twin-screw extruder in step (3), the temperature of the front zone is controlled at 90-100°C, the temperature of the middle zone is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is 50-60r / min, and the extrusion time is 12-15s.

[0019] By adopting the above technical solution, the present invention has the following advantages and beneficial effects:

[0020] 1) The multifunctional warm-mixing agent used in the present invention is a multifunctional polyethylene mixture grafted with a surfactant, which can achieve a dual warm-mixing effect on modified asphalt: the polyethylene mixture behaves as a non-Newtonian fluid after melting, and can be well miscible with asphalt, reducing the viscosity of the asphalt itself to achieve a warm-mixing effect; the surfactant grafted on its surface changes the contact state between the asphalt and the stone surface, increases the wetting effect of the asphalt on the stone to achieve a warm-mixing effect, and at the same time improves the adhesion between the asphalt and the stone, thereby improving the water damage resistance of the mixture.

[0021] 2) The polyethylene molecular chains in the multifunctional warm mix agent used in the present invention can be cross-linked with the SBS network structure in the asphalt, thereby enhancing the strength of the three-dimensional network structure in the modified asphalt, thereby greatly improving the high and low temperature performance of the asphalt mixture.

[0022] 3) The present invention uses activated rubber powder, which is combined with SBS and a multifunctional warm mix agent, thereby reducing the cost of the high-viscosity modifier. At the same time, the activated rubber powder can further improve the low-temperature crack resistance and fatigue performance of the mixture. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] The SBS modifier selected in the present invention is linear CH1301-1H, with a molecular weight of 80,000 to 120,000, and a block ratio of polystyrene segments to polybutadiene segments of 30 / 70;

[0025] The rubber powder selected in the present invention is a 40-mesh activated rubber powder provided by Jiangsu Zhonghong Environmental Protection Technology Co., Ltd.;

[0026] The polyethylene wax selected in the present invention is provided by Nanjing Tianshi New Materials Technology Co., Ltd., model PEW-0323;

[0027] The low-density polyethylene selected in the present invention is provided by Maoming Branch of China Petrochemical Corporation;

[0028] The nucleating agent required in the present invention is a sorbitol nucleating agent provided by Guangdong Weilinna New Materials Technology Co., Ltd., model WBQ-88;

[0029] The nonionic surfactant selected in the present invention is stearic acid diethanolamine, which is provided by Shanghai MacLean Biochemical Technology Co., Ltd.;

[0030] The filler oil selected in the present invention is naphthenic oil provided by Suzhou Saipahan Special Oil Products Co., Ltd., and the CN value is >40%.

[0031] Embodiment 1:

[0032] A direct-injection warm-mix high-viscosity modifier and a preparation method thereof. The components and their weight proportions include: 40 parts of SBS modifier, 20 parts of rubber powder, 10 parts of multifunctional warm-mix agent, and 10 parts of filler oil.

[0033] The multifunctional warm mix agent comprises, by weight, 100 parts of polyethylene wax, 4 parts of low-density polyethylene, 0.2 parts of nucleating agent and 2 parts of nonionic surfactant.

[0034] The preparation method of the direct-injection warm-mix high-viscosity modifier consists of the following steps:

[0035] (1) Preparation of a multifunctional warm-mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 minutes; then add a nucleating agent and a non-ionic surfactant, and continue stirring for 30-40 minutes; after cooling, grind the mixture into powder to obtain a multifunctional warm-mix agent.

[0036] (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and the multifunctional warm mix agent and mix evenly.

[0037] (3) melt-granulating the mixture in step (2) using a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

[0038] Specifically, in step (1), the stirring rate is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

[0039] In the twin-screw extruder granulation process described in the specific step (3), the front zone temperature is controlled at 90-100°C, the middle zone temperature is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60r / min, and the extrusion time is 12-15s.

[0040] Embodiment 2:

[0041] A direct-injection warm-mix high-viscosity modifier and a preparation method thereof. The components and their weight proportions include: 40 parts of SBS modifier, 20 parts of rubber powder, 15 parts of multifunctional warm-mix agent, and 10 parts of filler oil.

[0042] The multifunctional warm mix agent comprises, by weight, 100 parts of polyethylene wax, 5 parts of low-density polyethylene, 0.2 parts of nucleating agent and 2 parts of nonionic surfactant.

[0043] A method for preparing a direct-injection warm-mix high-viscosity modifier comprises the following steps:

[0044] (1) Preparation of a multifunctional warm-mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 minutes; then add a nucleating agent and a non-ionic surfactant, and continue stirring for 30-40 minutes; after cooling, grind the mixture into powder to obtain a multifunctional warm-mix agent.

[0045] (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and the multifunctional warm mix agent and mix evenly.

[0046] (3) melt-granulating the mixture in step (2) using a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

[0047] Specifically, in step (1), the stirring rate is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

[0048] In the twin-screw extruder granulation process described in the specific step (3), the front zone temperature is controlled at 90-100°C, the middle zone temperature is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60r / min, and the extrusion time is 12-15s.

[0049] Embodiment 3:

[0050] A direct-injection warm-mix high-viscosity modifier and a preparation method thereof. The components and their weight proportions include: 50 parts of SBS modifier, 20 parts of rubber powder, 20 parts of multifunctional warm-mix agent, and 12.5 parts of filler oil.

[0051] The multifunctional warm mix agent comprises, by weight, 100 parts of polyethylene wax, 5 parts of low-density polyethylene, 0.2 parts of nucleating agent and 3 parts of non-ionic surfactant.

[0052] A method for preparing a direct-injection warm-mix high-viscosity modifier comprises the following steps:

[0053] (1) Preparation of a multifunctional warm-mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 minutes; then add a nucleating agent and a non-ionic surfactant, and continue stirring for 30-40 minutes; after cooling, grind the mixture into powder to obtain a multifunctional warm-mix agent.

[0054] (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and the multifunctional warm mix agent and mix evenly.

[0055] (3) melt-granulating the mixture in step (2) using a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

[0056] Specifically, in step (1), the stirring rate is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

[0057] In the twin-screw extruder granulation process described in the specific step (3), the front zone temperature is controlled at 90-100°C, the middle zone temperature is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60r / min, and the extrusion time is 12-15s.

[0058] Embodiment 4:

[0059] A direct-injection warm-mix high-viscosity modifier and a preparation method thereof. The components and their weight proportions include: 50 parts of SBS modifier, 15 parts of rubber powder, 20 parts of multifunctional warm-mix agent, and 12.5 parts of filler oil.

[0060] The multifunctional warm mix agent comprises, by weight, 100 parts of polyethylene wax, 4 parts of low-density polyethylene, 0.2 parts of nucleating agent and 3 parts of non-ionic surfactant.

[0061] A method for preparing a direct-injection warm-mix high-viscosity modifier comprises the following steps:

[0062] (1) Preparation of a multifunctional warm-mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 minutes; then add a nucleating agent and a non-ionic surfactant, and continue stirring for 30-40 minutes; after cooling, grind the mixture into powder to obtain a multifunctional warm-mix agent.

[0063] (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and the multifunctional warm mix agent and mix evenly.

[0064] (3) melt-granulating the mixture in step (2) using a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

[0065] Specifically, in step (1), the stirring rate is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

[0066] In the twin-screw extruder granulation process described in the specific step (3), the front zone temperature is controlled at 90-100°C, the middle zone temperature is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60r / min, and the extrusion time is 12-15s.

[0067] Embodiment 5:

[0068] A direct-injection warm-mix high-viscosity modifier and a preparation method thereof. The components and their weight proportions include: 60 parts of SBS modifier, 10 parts of rubber powder, 25 parts of multifunctional warm-mix agent, and 15 parts of filler oil.

[0069] The multifunctional warm mix agent comprises, by weight, 100 parts of polyethylene wax, 3 parts of low-density polyethylene, 0.2 parts of nucleating agent and 4 parts of non-ionic surfactant.

[0070] A method for preparing a direct-injection warm-mix high-viscosity modifier comprises the following steps:

[0071] (1) Preparation of a multifunctional warm-mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 minutes; then add a nucleating agent and a non-ionic surfactant, and continue stirring for 30-40 minutes; after cooling, grind the mixture into powder to obtain a multifunctional warm-mix agent.

[0072] (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and the multifunctional warm mix agent and mix evenly.

[0073] (3) melt-granulating the mixture in step (2) using a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

[0074] Specifically, in step (1), the stirring rate is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

[0075] In the twin-screw extruder granulation process described in the specific step (3), the front zone temperature is controlled at 90-100°C, the middle zone temperature is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60r / min, and the extrusion time is 12-15s.

[0076] Comparative Example 1:

[0077] A direct injection modifier, the components and their weight proportions include: 40 parts of SBS modifier, 20 parts of rubber powder, and 10 parts of filler oil.

[0078] The preparation method comprises: weighing 40 parts of SBS modifier, adding 10 parts of filler oil, and mixing evenly; then adding 20 parts of rubber powder and mixing evenly; and using a twin-screw extruder to melt and granulate the mixture to obtain a direct-injection modifier.

[0079] During the granulation process of the twin-screw extruder, the front zone temperature is controlled at 90-100°C, the middle zone temperature is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60r / min, and the extrusion time is 12-15s.

[0080] Comparative Example 2:

[0081] A direct-injection warm-mix high-viscosity modifier and a preparation method thereof are characterized in that the components and their weight proportions include: 40 parts of SBS modifier, 20 parts of rubber powder, 10 parts of warm-mix agent, and 10 parts of filler oil.

[0082] The warm mix agent includes 100 parts of polyethylene wax, 4 parts of low-density polyethylene and 0.2 parts of nucleating agent by mass.

[0083] A method for preparing a direct-injection warm-mix high-viscosity modifier is characterized by comprising the following steps:

[0084] (1) Preparation of warm mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 minutes; then add nucleating agent and continue stirring for 30-40 minutes; after cooling, grind the mixture into powder to obtain warm mix agent.

[0085] (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and warm mix agent and mix evenly.

[0086] (3) melt-granulating the mixture in step (2) using a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

[0087] Specifically, in step (1), the stirring rate is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

[0088] In the twin-screw extruder granulation process described in the specific step (3), the front zone temperature is controlled at 90-100°C, the middle zone temperature is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60r / min, and the extrusion time is 12-15s.

[0089] Comparative Example 3:

[0090] A direct-injection warm-mix high-viscosity modifier and a preparation method thereof are characterized in that the components and their weight proportions include: 20 parts of SBS modifier, 40 parts of rubber powder, 10 parts of multifunctional warm-mix agent, and 10 parts of filler oil.

[0091] The multifunctional warm mix agent comprises, by mass fraction, 100 parts of polyethylene wax, 4 parts of low-density polyethylene, 0.2 parts of nucleating agent and 2 parts of non-ionic surfactant.

[0092] A method for preparing a direct-injection warm-mix high-viscosity modifier is characterized by comprising the following steps:

[0093] (1) Preparation of a multifunctional warm-mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 minutes; then add a nucleating agent and a non-ionic surfactant, and continue stirring for 30-40 minutes; after cooling, grind the mixture into powder to obtain a multifunctional warm-mix agent.

[0094] (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and the multifunctional warm mix agent and mix evenly.

[0095] (3) melt-granulating the mixture in step (2) using a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

[0096] Specifically, in step (1), the stirring rate is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

[0097] In the twin-screw extruder granulation process described in the specific step (3), the front zone temperature is controlled at 90-100°C, the middle zone temperature is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60r / min, and the extrusion time is 12-15s.

[0098] Performance Testing

[0099] (1) The modified asphalt was prepared by using the modifier prepared in the embodiment and the comparative example to evaluate the modification effect. Qilu 70# base asphalt was used, the asphalt was heated at 170-180°C, 6% of the asphalt mass modifier was added, and the modified asphalt was stirred at 500r / min for 30min to obtain the modified asphalt. The performance test was carried out according to the "Test Procedure for Asphalt and Asphalt Mixture for Highway Engineering" (JTG E20-2011), and the test results are shown in Table 1.

[0100] (2) The road performance of the modifiers prepared in the embodiments and comparative examples was evaluated. Conventional AC-13 asphalt mixture was used for the test. The base asphalt was Qilu 70# base asphalt, the stone was limestone, the oil-stone ratio was 5.0%, the modifier dosage was 6% of the base asphalt mass, and the modifier was added when the stone was dry mixed. The rest was carried out with reference to the "Test Procedure for Aggregates of Highway Engineering" (JTG 3432-2024), "Test Procedure for Asphalt and Asphalt Mixtures of Highway Engineering" (JTG E20-2011), and "Technical Specification for Highway Asphalt Pavement Construction" (JTG F40-2004). The test results are shown in Table 2.

[0101] Table 1 Test results of modifier-modified base asphalt performance

[0102]

[0103] Table 2 Performance test results of direct injection modified AC-13 asphalt mixture

[0104]

[0105] From Table 1, it can be found that the modified asphalt prepared by the modifier of the embodiment of the present invention has better high and low temperature performance and significantly reduced high temperature viscosity compared with the modified asphalt prepared by the modifier without adding the multifunctional warm mix agent component in Comparative Example 1, the modified asphalt prepared by the modifier without adding the non-ionic surfactant component in Comparative Example 2, and the modified asphalt prepared by the modifier with SBS and rubber powder components not within the specified range in Comparative Example 3. The proportions of the components in the modifier of the embodiment of the present invention are reasonably matched. The reasonable matching of SBS and rubber powder can significantly improve the high and low temperature performance of the modified asphalt, improve the stability of asphalt, and reduce the performance difference of the modified asphalt caused by segregation. The appropriate amount of rubber powder can reduce the cost; the warm mix agent component used has been functionally modified, and has better synergy with other components in the modifier, which can significantly reduce the viscosity of asphalt, and its molecular chain in the modified asphalt can enhance the three-dimensional network structure of the modified asphalt, thereby improving the performance of the modified asphalt.

[0106] Comparing Table 2, it can be found that the modified asphalt mixture prepared by the modifier of the embodiment of the present invention has a more obvious warm mixing effect than the modified asphalt mixture prepared by the modifier of Comparative Example 1 without adding the multifunctional warm mixing agent component. When the molding temperature is reduced by 30°C, it still has excellent high and low temperature performance and water damage resistance. Compared with the modified asphalt mixture prepared by the modifier of Comparative Example 2 without adding the non-ionic surfactant component, its warm mixing effect is better. This is because the warm mixing agent component used in the present invention has been functionally modified, not only to reduce the viscosity of the asphalt itself to achieve warm mixing, but also to graft a surfactant to change the interface state between asphalt and stone, and increase the wetting and coating effect of asphalt on stone, so it shows a better warm mixing effect and water damage resistance. Compared with the modified asphalt mixture prepared by the modifier of Comparative Example 3, in which the SBS and rubber powder components are not within the specified range, the reasonable combination of each component and the higher proportion of SBS components can significantly improve the strength, high and low temperature performance and water damage resistance of the asphalt mixture.

[0107] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A direct-injection warm-mix high-viscosity modifier, characterized in that: The components include: 40-60 parts of SBS modifier, 10-20 parts of rubber powder, 10-25 parts of multifunctional warm mix agent, and 10-15 parts of filler oil by weight; The multifunctional warm mix agent comprises, by weight: 100 parts of polyethylene wax, 3 to 5 parts of low-density polyethylene, 0.2 parts of a nucleating agent, and 2 to 4 parts of a nonionic surfactant.

2. A direct-injection warm-mix high-viscosity modifier according to claim 1, characterized in that: The SBS modifier is a styrene-butadiene-styrene block copolymer, and the block ratio of the polystyrene segment to the polybutadiene segment is 3:

7.

3. A direct-injection warm-mix high-viscosity modifier according to claim 1, characterized in that: The rubber powder is activated rubber powder obtained by desulfurizing and activating waste tire rubber powder, and the mesh number is ≥40 meshes.

4. A direct-injection warm-mix high-viscosity modifier according to claim 1, characterized in that: The filler oil is cycloparaffinic oil, and the CN value is >40%.

5. A direct-injection warm-mix high-viscosity modifier according to claim 1, characterized in that: The nucleating agent is sorbitol nucleating agent.

6. A direct-injection warm-mix high-viscosity modifier according to claim 1, characterized in that: The nonionic surfactant is one or more of stearic acid diethanolamine, monostearate glyceryl or polyethylene glycol stearate.

7. A method for preparing the direct-injection warm-mix high-viscosity modifier according to any one of claims 1 to 6, characterized in that: The following steps are involved: (1) Preparation of multifunctional warm-mix agent: Heat polyethylene wax to 160-170°C, add low-density polyethylene and continue stirring for 20 min; then add nucleating agent and non-ionic surfactant and continue stirring for 30-40 min; after cooling, grind the mixture into powder to obtain a multifunctional warm-mix agent; (2) Weigh the SBS modifier by mass, add the filler oil, and mix evenly; then add the rubber powder and the multifunctional warm mix agent and mix evenly; (3) The mixture in step (2) is melt-granulated by a twin-screw extruder to obtain a direct-injection warm-mix high-viscosity modifier.

8. The method for preparing a direct-injection warm-mix high-viscosity modifier according to claim 7, characterized in that: The stirring rate in step (1) is 300 r / min; the grinding temperature is -60±5°C, the rotation speed is 1000 r / min, and the grinding time is 3 min.

9. The method for preparing a direct-injection warm-mix high-viscosity modifier according to claim 7, characterized in that: During the granulation process of the twin-screw extruder in step (3), the temperature of the front zone is controlled at 90-100°C, the temperature of the middle zone is 150-160°C, the terminal base temperature is 100-110°C, the screw speed is controlled at 50-60 r / min, and the extrusion time is 12-15 s.

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