WO2019242556A1 - Graphene composite rubber asphalt modifier and preparation method therefor and use thereof - Google Patents

Abstract

Disclosed are a graphene composite rubber asphalt modifier and a preparation method therefor and the use thereof, wherein the graphene composite rubber asphalt modifier comprises the following components in parts by weight: 0.00005-0.01 part of a graphene powder, 3-23 parts of a dispersion medium, 78-92 parts of a rubber powder, and 0.05-6 parts of an additive. The preparation method comprises the following steps: (1) mixing the graphene powder and the dispersion medium and mechanically stirring same, and then dispersing same at a high speed so as to obtain a graphene dispersion solution; and (2) banburying the graphene dispersion solution with the rubber powder and the additive, to prepare the graphene composite rubber asphalt modifier.

Description

Graphene composite rubber asphalt modifier, preparation method and application thereof Technical field

The invention relates to the field of asphalt modifiers, in particular to a graphene composite rubber asphalt modifier, and a preparation method and application thereof.

Background technique

Asphalt pavement has the characteristics of comfortable driving, quiet driving and convenient maintenance. At present, more than 95% of the roads in the world are paved with asphalt pavement. The important material composition of asphalt pavement ranges from the original residual oil, experienced ordinary asphalt, heavy traffic asphalt to current usage. With more than 50% of modified asphalt, with the rapid development of rapid economic development, the traffic load has increased rapidly. Asphalt pavements constructed of ordinary asphalt or heavy traffic asphalt have various problems, such as cracks, ruts, and deformation due to insufficient high-temperature performance. Many problems such as cracking of the pavement caused by insufficient low temperature performance can no longer meet the requirements of practical use. Rubber asphalt is an asphalt cementing material formed by processing rubber powder from waste tires and then fully blending with matrix asphalt in a certain proportion. The high temperature stability, rut resistance, and fatigue resistance of waste rubber modified asphalt mixtures are equal to or slightly better than SBS modified asphalt, but they are more in line with environmental protection requirements and have attracted more and more attention from all walks of life. However, in the practical application of rubber powder modified asphalt, there are still some technical problems that need to be solved urgently. The compatibility between rubber and matrix asphalt is insufficient, resulting in poor storage stability of the modified asphalt. The processing process requires high temperature and is accompanied by Severe odor and secondary pollution of dust and other problems, and then affect the large-scale application of rubber asphalt.

Graphene is a new type of functional material. The carbon atoms in the structure are connected by a strong σ bond, which makes the graphene sheet have excellent mechanical properties. At present, there are two methods for preparing two-dimensional graphene: one is a top-down method, which is to obtain graphene from the decomposition of graphite or carbon nanotubes with a higher structure than graphene, such as mechanical peeling, insertion Layer stripping method, solvent liquid phase stripping method and redox method; the other is a bottom-up method, which uses a carbon source (small molecules such as methane, CO, alcohol, etc.) with a lower structure than graphene to pass CVD, Graphene is prepared by arc discharge, solvothermal method, and the like. The performance of graphene in specific applications is closely related to the preparation method.

At present, most graphene asphalts use graphene oxide, with graphene oxide as an additive, and SBS as a modifier, mixed with matrix asphalt and sulfur-containing accelerators to obtain graphene-modified asphalt; or matrix asphalt and The modifier is mixed, and then the carboxyl-modified graphene oxide is added to obtain a polyethylene-modified asphalt based on the carboxyl-modified graphene oxide. In addition, graphene oxide and ethanol are dispersed ultrasonically in a certain proportion to prepare graphene oxide The sol is uniformly mixed and stirred with the medium-temperature coal pitch until the solvent in the pitch is evaporated, and the final product is obtained. The prior art shows that the addition of graphene can improve asphalt adhesion, mechanical properties, high and low temperature stability, and high temperature rut resistance.

However, because graphene oxide is hydrophilic and has poor compatibility with asphalt, despite functionalizing it, graphene oxide is still a two-dimensional sheet structure. It is necessary to fully disperse graphene in asphalt directly, which is technically certain. Difficulty: In the prior art, nitrogen or sulfur-doped graphene is used to increase the degree of cross-linking of graphene and asphalt, but sulfur-containing substances are not environmentally friendly. If harmful substances are released during construction, health will be endangered.

The current process of graphene pitch is roughly as follows: graphene is functionalized, and graphene, asphalt, and modifiers are blended and blended. This blending and blending method makes the interface performance of the three poor. Poor capacitance results in poor dispersion of graphene in asphalt, and stability cannot be guaranteed.

Therefore, using graphene blending method to directly disperse graphene in asphalt requires a relatively high amount of addition to enhance the effect. In the prior art, the amount of graphene added accounted for 0.1% to 5% of the total mass of the asphalt. Some even go above 10%. This greatly increases the cost of graphene-modified asphalt, which is not conducive to popularization.

The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that the information constitutes prior art that is already known to a person of ordinary skill in the art.

Summary of the Invention

The purpose of the present invention is to provide a graphene composite rubber asphalt modifier and a preparation method and application thereof. The graphene composite rubber asphalt modifier can greatly improve the compatibility and stability of rubber powder in asphalt, and can improve the Adhesive performance of modified asphalt and sand and gravel, high and low temperature stability performance, at the same time reduce the temperature of the road surface and extend the service life of the road surface.

In order to achieve the above object, the present invention provides a graphene composite rubber asphalt modifier, which includes the following components by weight: graphene powder 0.00005-0.01 parts, dispersion medium 3-23 parts, rubber powder 78-92 parts And additives of 0.05-6 parts; Preferably, the graphene composite rubber asphalt modifier includes the following components by weight: graphene powder 0.0001-0.005 parts, dispersion medium 5-20 parts, rubber powder 80-90 0.1-5 parts of additives, and further preferably, the graphene composite rubber asphalt modifier includes the following components by weight: 0.003 parts of graphene powder, 13 parts of dispersion medium, 85 parts of rubber powder, and additives 2.5 servings.

In a preferred embodiment, the graphene powder is selected from at least one of graphene microchips, reduced graphene oxide, and three-dimensional structure graphene; preferably, the graphene powder is three-dimensional structure graphene ; Further preferably, the specific surface area of the graphene powder is greater than or equal to 300 m2 / g; wherein the graphene microplatelets (Graphene Nanoplatelets) refer to those having less than 10 carbon layers and a lateral dimension in the range of 100 nm to 1000 microns Ultra-thin layered graphene layered body; reduced graphene oxide is the first oxidation of graphite to graphite oxide, and then to graphene oxide by exfoliation, and finally through various reduction methods (to obtain excellent performance in electrochemical, photochemical and other properties Graphene; three-dimensional structure graphene is a powder material with a honeycomb-like structure composed of two-dimensional graphene sheets, and its basic structural characteristics meet the requirements of technical standards DB 45 / T 1421-2016 and DB 45 / T 1425-2016 .

In a preferred embodiment, the dispersion medium is selected from at least one of paraffin rubber oil, aromatic rubber oil, naphthenic rubber oil, and polycyclic aromatic rubber oil; preferably, the dispersion medium is selected At least one of a self-paraffin rubber oil, an aromatic rubber oil and a naphthenic rubber oil; further preferably, the dispersion medium is a naphthenic rubber oil.

In a preferred embodiment, the powder size of the rubber powder is 20-200 mesh; preferably, the powder size of the rubber powder is 30-150 mesh; further preferably, the powder size of the rubber powder is 40 -80 mesh.

In a preferred embodiment, the additive is selected from the group consisting of acrylonitrile-butadiene-styrene copolymer, polyethylene, ethylene bisstearic acid amide, C9 petroleum resin, C12 petroleum resin, and silane coupling agent KH- 580, at least one of silane coupling agent KH550, silane coupling agent KH792, dodecyltrimethoxysilane, cetyltrimethoxysilane, dispersant KC163, dispersant BYK110, dispersant BYK164; preferably The additive is at least one selected from the group consisting of acrylonitrile-butadiene-styrene copolymer, polyethylene, and ethylene bisstearate; further preferably, the additive is acrylonitrile-butadiene- Copolymer of styrene. This additive is used to increase the interfacial interaction between graphene and rubber powder and to stabilize the dispersion of graphene.

The invention also provides a method for preparing a graphene composite rubber asphalt modifier, comprising the following steps: (1) mixing graphene powder and a dispersion medium, mechanically stirring, and then obtaining a graphene dispersion liquid through high-speed dispersion (2) The graphene dispersion liquid is densely mixed with rubber powder and additives to prepare the graphene composite rubber asphalt modifier.

In a preferred embodiment, in step (1), the mass ratio of the graphene powder mixed with the dispersion medium is (0.00005-0.01): (3-23); preferably, the graphene powder The mass ratio for mixing with the dispersion medium is (0.0001-0.005): (5-20); further preferably, the mass ratio for mixing the graphene powder and the dispersion medium is 0.003: 13.

In a preferred embodiment, in step (1), the high-speed dispersion is performed by dispersing the graphene powder and the liquid mixed with the dispersion medium at a temperature of 60-120 ° C for 10-60 minutes by using a high-speed shearing machine, and obtaining the solution after cooling. Graphene dispersion liquid, the graphene sheet diameter distribution in the graphene dispersion liquid is 100-2000 nanometers; preferably, the high-speed shearing machine disperses the liquid after the graphene and the dispersion medium are mixed at 70 ° C. 20 -50min; further preferably, the high-speed shearing machine disperses the graphene powder and the liquid mixed with the dispersion medium at 70 ° C for 35min; further preferably, the sheet diameter distribution of the graphene in the graphene dispersion liquid It is 500-1000 nm.

In a preferred embodiment, in the step (2), the graphene dispersion liquid, the rubber powder and the additive are added at a mass ratio of (3-23): (78-92): (0.05-6) to 200-260 ° C. The mixture is kneaded for 10-60 minutes, and then cooled to prepare a graphene composite rubber asphalt modifier. Preferably, in step (2), the graphene dispersion liquid, rubber powder and additives are (5-20): (80 -90): (0.1-5) mass mixing and kneading at 220-240 ° C for 20-50min; further preferably, in step (2), the graphene dispersion liquid, rubber powder and additives are added at 13:85: The mass ratio of 2.5 was kneaded and kneaded at 230 ° C for 35 minutes.

The invention also provides the application of the graphene composite rubber asphalt modifier or the preparation method thereof to the asphalt modifier.

Compared with the prior art, the present invention has the following beneficial effects:

(1) the graphene composite rubber asphalt modifier according to the present invention is selected from at least one of graphene microflakes, reduced graphene oxide, and three-dimensional structure graphene, and has better dispersibility than graphene oxide;

(2) The preparation method of the graphene composite rubber asphalt modifier according to the present invention adopts a high-temperature compaction process to fully mix graphene and rubber powder, improve the modification effect of graphene, and avoid direct graphene and the matrix Insufficient dispersion caused by asphalt mixing;

(3) The combination of the graphene powder and the high-temperature compaction process used in the present invention, the use of less than 0.01% of the graphene powder in the asphalt can achieve better results, greatly reducing the cost of graphene-modified asphalt, The graphene composite rubber asphalt modifier can greatly improve the compatibility and stability of rubber powder in asphalt, improve the bonding performance of modified asphalt and sand and gravel, high and low temperature stability, and reduce the temperature and extension of the road surface. Road life.

detailed description

The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

Unless explicitly stated otherwise, throughout the specification and claims, the term "comprising" or variations thereof such as "comprising" or "including" will be understood to include the stated element or component, and No other element or component is excluded.

Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

The materials, reagents, etc. used in the following examples are commercially available unless otherwise specified.

Example 1 Components and preparation method of graphene composite rubber asphalt modifier

The graphene composite rubber asphalt modifier components are shown below (by parts by weight)

The specific surface area of the three-dimensional graphene is 500 m2 / g, and the powder particle size of the rubber powder is 60 mesh.

The preparation method of the graphene composite rubber asphalt modifier is as follows:

(1) Mixing the three-dimensional structure graphene and the naphthenic rubber oil at a mass ratio of 0.003: 13, mechanically stirring, and dispersing at 90 ° C for 35 minutes using a high-speed shearing machine, and obtaining a graphene dispersion liquid after cooling;

(2) The graphene dispersion prepared above, the rubber powder and the acrylonitrile-butadiene-styrene copolymer were added to the mixer in a mass ratio of 13: 85: 2.5, and then kneaded at 230 ° C for 35 minutes at high temperature. After cooling, it is made into graphene composite rubber asphalt modifier.

Example 2 Components and preparation method of graphene composite rubber asphalt modifier

The graphene composite rubber asphalt modifier components are shown below (by parts by weight)

The specific surface area of the reduced graphene oxide is 400 m2 / g, and the powder particle size of the rubber powder is 40 mesh.

The preparation method of the graphene composite rubber asphalt modifier is as follows:

(1) mixing the reduced graphene oxide and the aromatic rubber oil in a mass ratio of 0.0001: 5, mechanically stirring, and dispersing for 20 minutes using a high-speed shearing machine at 60 ° C, and obtaining a graphene dispersion liquid after cooling;

(2) Add the prepared graphene dispersion, rubber powder, and polyethylene to the mixer at a mass ratio of 5: 80: 0.1, and mix and knead at 220 ° C for 20 minutes at high temperature. After cooling, make a graphene composite. Rubber asphalt modifier.

Example 3 Components and Preparation Method of Graphene Composite Rubber Asphalt Modifier

The graphene composite rubber asphalt modifier components are shown below (by parts by weight)

The specific surface area of the graphene microchip is 600 m2 / g, and the powder particle size of the rubber powder is 80 mesh.

The preparation method of the graphene composite rubber asphalt modifier is as follows:

(1) The graphene microchips and the paraffinic rubber oil are mixed at a mass ratio of 0.005: 20, mechanically stirred, and dispersed at 120 ° C. for 50 minutes using a high-speed shearing machine, and cooled to obtain a graphene dispersion liquid.

(2) Add the prepared graphene dispersion, rubber powder, and ethylenebisstearic acid amide to the internal mixer at a mass ratio of 20: 90: 5, and perform high-temperature internal mixing and kneading at 240 ° C for 50 minutes. After cooling, Made of graphene composite rubber asphalt modifier.

Example 4 Graphite-free Rubber Asphalt Modifier

The components of the graphene-free rubber asphalt modifier are shown below (in parts by weight)

Naphthenic rubber oil 12 servings

Rubber powder: 87 copies

Acrylonitrile-butadiene-styrene copolymer 1 part

Except that no graphene powder is added, the preparation method of the graphene-free rubber asphalt modifier is the same as in Example 1.

Comparative example

The graphene composite rubber asphalt modifier in Example 1-3 and the non-graphene rubber asphalt modifier in Example 4 were used to modify the 70 # matrix asphalt, respectively. The weight ratio of the graphene composite rubber asphalt modifier modifier to the matrix asphalt is 20:80, and the weight ratio of the graphene-free rubber asphalt modifier to matrix asphalt according to Example 4 is 20:80. The test uses relevant technology Standard specifications are carried out. Among them, the technical specifications of graphene rubber asphalt modifiers are shown in Table 1, and the specifications of graphene rubber asphalt mixtures (that is, after the modifier is added to the asphalt) are shown in Table 2.

Table 1 Product technical indicators

Table 2 Graphene rubber asphalt mixture (AC-16C) index

It can be obtained from the above Table 1 that the graphite thin composite rubber asphalt modifier in Examples 1-3 is higher than the graphene-free rubber asphalt modified in Example 4 in both the modified softening point and the 10 ° C ductility. Agent, and after adding the modifiers mentioned in Examples 1-4 to the asphalt, according to Table 2, it can be obtained at 60 ° C, 0.7Mpa dynamic stability, immersed Marshall residual stability, low-temperature fracture bending tensile strength, and In terms of stiffness modulus, the graphene rubber asphalt mixture mixed with the graphene composite rubber asphalt modifiers according to Examples 1-3 is far more modified than the graphene rubber asphalt mixed with Example 4 Agent of graphene rubber asphalt mixture, thereby further confirming that the graphene composite rubber asphalt modifier of the present invention can greatly improve the compatibility and stability of rubber powder in asphalt.

The foregoing description of specific exemplary embodiments of the present invention has been provided for the purposes of illustration and illustration. These descriptions are not intended to limit the invention to the precise forms disclosed, and it is apparent that many changes and modifications can be made in light of the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can implement and utilize the various exemplary embodiments of the present invention and various different Choose and change. It is intended that the scope of the invention be defined by the Claims and their equivalents.

Claims (20)

A graphene composite rubber asphalt modifier, which is characterized by comprising the following components by weight: 0.00005-0.01 parts of graphene powder, 3-23 parts of dispersion medium, 78-92 parts of rubber powder, and 0.05- 6 servings. The graphene composite rubber asphalt modifier according to claim 1, comprising the following components by weight: 0.0001 to 0.005 parts of graphene powder, 5 to 20 parts of dispersion medium, and 80 to 90 parts of rubber powder , And 0.1-5 parts of additives. The graphene composite rubber asphalt modifier according to claim 1, wherein the graphene powder is at least one selected from the group consisting of graphene microflakes, reduced graphene oxide, and three-dimensional graphene. The graphene composite rubber asphalt modifier according to claim 3, wherein the graphene powder is a three-dimensional structured graphene. The graphene composite rubber asphalt modifier according to claim 1, wherein the specific surface area of the graphene powder is ≥300 m2 / g. The graphene composite rubber asphalt modifier according to claim 1, wherein the dispersion medium is selected from the group consisting of paraffin rubber oil, aromatic rubber oil, naphthenic rubber oil, and polycyclic aromatic rubber oil. At least one. The graphene composite rubber asphalt modifier according to claim 6, wherein the dispersion medium is at least one selected from the group consisting of paraffin rubber oil, aromatic rubber oil, and naphthenic rubber oil. The graphene composite rubber asphalt modifier according to claim 1, wherein the rubber powder has a particle size of 20-200 mesh. The graphene composite rubber asphalt modifier according to claim 8, wherein the rubber powder has a particle size of 30-150 mesh. The graphene composite rubber asphalt modifier according to claim 1, wherein the additive is selected from the group consisting of acrylonitrile-butadiene-styrene copolymer, polyethylene, ethylene distearate, and C9 petroleum Resin, C12 petroleum resin, silane coupling agent KH-580, silane coupling agent KH550, silane coupling agent KH792, dodecyltrimethoxysilane, cetyltrimethoxysilane, dispersant KC163, dispersant At least one of BYK110 and BYK164. The graphene composite rubber asphalt modifier according to claim 10, wherein the additive is at least one selected from the group consisting of acrylonitrile-butadiene-styrene copolymer, polyethylene, and ethylene distearate. One. A method for preparing a graphene composite rubber asphalt modifier, comprising the following steps: (1) mixing graphene powder and a dispersion medium, mechanically stirring, and then obtaining a graphene dispersion liquid through high-speed dispersion; (2) mixing the graphene dispersion liquid with a rubber powder and an additive to prepare the graphene composite rubber asphalt modifier according to claim 1. The method according to claim 12, wherein in step (1), the mass ratio of the graphene powder and the dispersion medium is (0.00005-0.01): (3-23). The method according to claim 13, wherein in step (1), the mass ratio of the graphene powder mixed with the dispersion medium is (0.0001-0.005): (5-20). The preparation method according to claim 12, characterized in that in step (1), the high-speed dispersion is performed by using a high-speed shearing machine at a temperature of 60-120 ° C to disperse the liquid in which the graphene powder and the dispersion medium are mixed. After -60 min, a graphene dispersion is obtained after cooling, and the graphene sheet diameter distribution in the graphene dispersion is 100-2000 nm. The method according to claim 15, wherein in step (1), the high-speed shearing machine disperses the liquid after the graphene and the dispersion medium are mixed at 70 ° C for 20-50 minutes. The method according to claim 15, wherein in step (1), the sheet diameter distribution of graphene in the graphene dispersion is 500-1000 nm. The preparation method according to claim 12, characterized in that in the step (2), the graphene dispersion liquid, the rubber powder and the additive are in a mass of (3-23): (78-92): (0.05-6) The mixture is kneaded and kneaded at 200-260 ° C for 10-60 minutes. After cooling, it is made into a graphene composite rubber asphalt modifier. The method according to claim 18, wherein in the step (2), the graphene dispersion liquid, the rubber powder and the additive are in a mass of (5-20): (80-90): (0.1-5) Than knead and knead at 220-240 ° C for 20-50min. Application of the graphene composite rubber asphalt modifier according to any one of claims 1 to 11 or the preparation method according to any one of claims 12 to 19 to an asphalt modifier.