阅读说明：本技术 沥青改性剂及制备工艺 (Asphalt modifier and preparation process thereof ) 是由 王随原 曾峰 蔡文浩 程昊 于 2020-05-22 设计创作，主要内容包括：本发明公开了一种沥青改性剂,包括以下重量份数的原料：20～30份的石墨烯、10～15份的碳纳米管、4～8份的多巴胺、15～25份的植物油多元醇、30～40份的聚四氟乙烯纤维和1～3份的稳定剂。本发明与沥青相容性较好,提高与沥青的粘接性,避免离析现象的发生；采用植物油多元醇作为溶剂,可提高其他各组分的分散性,提高有效物的利用率；引入多巴胺、石墨烯具有明显的改善沥青抗氧老化性能的功效,进而达到提高沥青耐久性的目的。(The invention discloses an asphalt modifier, which comprises the following raw materials in parts by weight: 20-30 parts of graphene, 10-15 parts of carbon nano tubes, 4-8 parts of dopamine, 15-25 parts of vegetable oil polyol, 30-40 parts of polytetrafluoroethylene fibers and 1-3 parts of stabilizer. The asphalt has good compatibility with asphalt, improves the adhesion with the asphalt and avoids the occurrence of segregation phenomenon; vegetable oil polyalcohol is used as a solvent, so that the dispersibility of other components can be improved, and the utilization rate of effective substances is improved; the introduction of dopamine and graphene has the effect of obviously improving the anti-oxidation and anti-aging performance of the asphalt, so that the aim of improving the durability of the asphalt is fulfilled.)

1. The asphalt modifier is characterized by comprising the following raw materials in parts by weight: 20-30 parts of graphene, 10-15 parts of carbon nano tubes, 4-8 parts of dopamine, 15-25 parts of vegetable oil polyol, 30-40 parts of polytetrafluoroethylene fibers and 1-3 parts of stabilizer.

2. The asphalt modifier of claim 1, wherein the stabilizer is sulfur.

3. The asphalt modifier according to claim 1, wherein the graphene is pretreated, specifically:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.3-0.7 mg/mL, and performing ultrasonic treatment for 2-2.5 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, and stirring the colloidal solution at a stirring speed of 1000-1500 r/min to foam for 40-60 min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to graphene in the colloidal solution is 0.03-0.1: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

4. The asphalt modifier of claim 3, wherein the surfactant in step S2 is sodium dodecyl sulfate.

5. A process for preparing an asphalt modifier according to any one of claims 1 to 4, which comprises the steps of:

step one, dispersing 20-30 parts of graphene in water, performing ultrasonic oscillation treatment for 10-20 min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 30-60 ℃ for treatment, and performing freeze drying and crushing after 2-4 h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

dispersing 30-40 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 10-15 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 800-1200 r/min for 30-40 min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

and step three, uniformly mixing the modified graphene obtained in the step one, the modified polytetrafluoroethylene fiber obtained in the step two, 15-25 parts of vegetable oil polyol and 1-3 parts of stabilizer to obtain the asphalt modifier.

6. The preparation process of the asphalt modifier according to claim 5, wherein the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed in the third step, and the preparation process specifically comprises the following steps: and (3) adding a plurality of positive charges to the modified polytetrafluoroethylene obtained in the step two by adopting a corona discharge method.

Technical Field

The invention relates to the technical field of asphalt, in particular to an asphalt modifier and a preparation process thereof.

Background

In order to accelerate the construction process of the traffic road, the prior concrete road technology is gradually eliminated by the asphalt pavement technology, the asphalt pavement is the most extensive high-grade pavement adopted in the current road construction, and has the advantages of short construction period, convenient maintenance, no dust emission, easy cleaning and the like.

The asphalt modifier commonly used at present has the following defects: (1) the adhesion with asphalt is poor, and the segregation phenomenon is easy to occur; (2) the dispersibility of each component of the modifier is poor, so that the utilization rate of effective substances is low; (3) the anti-aging performance of the asphalt is not obviously improved.

Disclosure of Invention

An object of the present invention is to solve the above-mentioned problems and to provide at least the advantages which will be described later.

Still another object of the present invention is to provide an asphalt modifier, which has good compatibility with asphalt, improves adhesion with asphalt, and avoids segregation; vegetable oil polyalcohol is used as a solvent, so that the dispersibility of other components can be improved, and the utilization rate of effective substances is improved; the introduction of dopamine and graphene has the effect of obviously improving the anti-oxidation and anti-aging performance of the asphalt, so that the aim of improving the durability of the asphalt is fulfilled.

To achieve these objects and other advantages in accordance with the present invention, there is provided an asphalt modifier comprising the following raw materials in parts by weight: 20-30 parts of graphene, 10-15 parts of carbon nano tubes, 4-8 parts of dopamine, 15-25 parts of vegetable oil polyol, 30-40 parts of polytetrafluoroethylene fibers and 1-3 parts of stabilizer.

Preferably, the asphalt modifier and the stabilizer are sulfur.

Preferably, the asphalt modifier is prepared by pretreating graphene, specifically:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.3-0.7 mg/mL, and performing ultrasonic treatment for 2-2.5 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, and stirring the colloidal solution at a stirring speed of 1000-1500 r/min to foam for 40-60 min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to graphene in the colloidal solution is 0.03-0.1: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

Preferably, the surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 20-30 parts of graphene in water, performing ultrasonic oscillation treatment for 10-20 min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 30-60 ℃ for treatment, and performing freeze drying and crushing after 2-4 h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

dispersing 30-40 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 10-15 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 800-1200 r/min for 30-40 min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

and step three, uniformly mixing the modified graphene obtained in the step one, the modified polytetrafluoroethylene fiber obtained in the step two, 15-25 parts of vegetable oil polyol and 1-3 parts of stabilizer to obtain the asphalt modifier.

Preferably, in the preparation process of the asphalt modifier, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed in the third step, and the preparation process specifically comprises the following steps: and (3) adding a plurality of positive charges to the modified polytetrafluoroethylene obtained in the step two by adopting a corona discharge method.

The invention at least comprises the following beneficial effects:

1. the asphalt is a colloid structure, and specifically comprises saturated components, aromatic components, asphaltenes and resin (colloid), wherein the asphaltenes with the largest polarity serve as centers, and the colloid is adsorbed around the asphaltenes to form micelles which are dispersed in oil components formed by the saturated components and the aromatic components; the vegetable oil polyhydric alcohol is used as a solvent of the modifier, the vegetable oil contains polar ester groups and nonpolar straight-chain alkane, and the vegetable oil polyhydric alcohol is used as an interfacial agent and is filled between the asphaltene and the oil component of the asphalt, so that the compatibility of the modifier and the asphalt is improved, and the stability of a colloid structure of the asphalt is improved; in addition, other components, namely graphene and polytetrafluoroethylene can be well and uniformly dispersed in the vegetable oil polyol, and can be uniformly mixed with the asphalt matrix, so that the utilization rate of the graphene and the polytetrafluoroethylene is improved;

2. the graphene is a hexagonal two-dimensional carbon nano material in a honeycomb lattice form, which is formed by carbon atoms in sp2 hybridized tracks, has a certain reinforcement effect in the asphalt, and forms a net structure with the asphalt matrix, so that oxygen in the air can be effectively prevented from permeating into the asphalt, or the path of oxygen in the air permeating into the asphalt is increased, and the effect of improving the anti-oxygen aging performance of the asphalt is achieved; dopamine can combine with oxygen permeating into asphalt to generate self-polymerization-crosslinking reaction, can show high-affinity adhesion effect, is firstly oxidized into dopaquinone, generates semiquinone free radicals after oxidation, and finally forms polydopamine through crosslinking, and a net structure of the polydopamine, graphene and asphalt further form a compact protective film to better prevent further permeation of oxygen;

3. the polytetrafluoroethylene is a polymer polymerized by a tetrafluoroethylene monomer, is a transparent or opaque wax similar to PE, has excellent high and low temperature resistance and strong chemical stability, and is less applied to an asphalt modifier due to poor adhesion of the polytetrafluoroethylene, the polytetrafluoroethylene can prevent the aggregation of the graphene by combining the polytetrafluoroethylene with the graphene, and meanwhile, the graphene can improve the adhesion and has a mutual synergistic effect, so that the technical effect that 1 plus 1 is more than 2 is achieved;

4. preprocessing graphene to obtain spongy aerogel of light graphene, opening pore channels of the graphene to avoid the agglomeration of the graphene, and filling a modifier or a substance in an asphalt matrix into the pore channels of the graphene to further improve the compatibility of the substances; in the preparation process of the asphalt modifier, dopamine is adsorbed on graphene in advance, but the dopamine is uniformly dispersed, and the graphene is pretreated, so that more and more uniform dopamine can be adsorbed, and the effect of improving the antioxidant aging performance of asphalt is improved; the carbon nano tube is also an easily-agglomerated carbon nano material, and the carbon nano tube is uniformly adsorbed on the polytetrafluoroethylene in advance, so that on one hand, the weak adhesion of the polytetrafluoroethylene is improved, and on the other hand, the dispersity of the carbon nano tube can be improved;

5. the modified polytetrafluoroethylene is subjected to electret treatment, and has positive charges, and the modified polytetrafluoroethylene is graphene. A pi-pi conjugated interaction is formed between a benzene ring structure in dopamine and graphene, a dopamine stabilizer is adsorbed on the surface of the graphene, so that a modified graphene sheet layer has high electronegativity, and the modified polytetrafluoroethylene after electret can be well combined with the modified graphene, so that all components are uniformly dispersed.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Detailed Description

The present invention is further described in detail below with reference to examples so that those skilled in the art can practice the invention with reference to the description.

< example 1>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 20 parts of graphene, 10 parts of carbon nano tubes, 4 parts of dopamine, 15 parts of vegetable oil polyol, 30 parts of polytetrafluoroethylene fibers and 1 part of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.3mg/mL, and performing ultrasonic treatment for 2 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1000r/min, and foaming for 40min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.03: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 20 parts of graphene in water, performing ultrasonic oscillation treatment for 10min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 30 ℃ for treatment, and performing freeze drying and crushing after 2h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

dispersing 30 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 10 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 800r/min for 30min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

and step three, uniformly mixing the modified graphene obtained in the step one, the modified polytetrafluoroethylene fiber obtained in the step two, 15 parts of vegetable oil polyol and 1 part of stabilizer to obtain the asphalt modifier.

In the third step, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed, and the steps are as follows: and (3) adding a plurality of positive charges to the modified polytetrafluoroethylene obtained in the step two by adopting a corona discharge method.

< example 2>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 30 parts of graphene, 15 parts of carbon nanotubes, 8 parts of dopamine, 25 parts of vegetable oil polyol, 40 parts of polytetrafluoroethylene fibers and 3 parts of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.7mg/mL, and performing ultrasonic treatment for 2.5 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1500r/min, and foaming for 60min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.1: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 30 parts of graphene in water, performing ultrasonic oscillation treatment for 20min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillation instrument at the temperature of 30-60 ℃ for treatment, and performing freeze drying and crushing after 4h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

dispersing 40 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 15 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 1200r/min for 40min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

step three, uniformly mixing the modified graphene obtained in the step one, the modified polytetrafluoroethylene fiber obtained in the step two, 25 parts of vegetable oil polyol and 3 parts of stabilizer to obtain the asphalt modifier.

In the third step, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed, and the steps are as follows: and D, adding a plurality of positive charges to the modified polytetrafluoroethylene obtained in the step two by adopting a corona discharge method.

< example 3>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 13 parts of carbon nanotubes, 6 parts of dopamine, 20 parts of vegetable oil polyol, 35 parts of polytetrafluoroethylene fibers and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.5mg/mL, and performing ultrasonic treatment for 2.3 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1300r/min, and foaming for 50min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.07: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 25 parts of graphene in water, performing ultrasonic oscillation treatment for 15min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 45 ℃ for treatment, and performing freeze drying and crushing after 3h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

dispersing 35 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 13 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 1000r/min for 35min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

step three, uniformly mixing the modified graphene obtained in the step one, the modified polytetrafluoroethylene fiber obtained in the step two, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

In the third step, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed, and the steps are as follows: and (3) adding a plurality of positive charges to the modified polytetrafluoroethylene obtained in the step two by adopting a corona discharge method.

< comparative example 1>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 13 parts of carbon nanotubes, 6 parts of dopamine, 20 parts of water, 35 parts of polytetrafluoroethylene fibers and 2 parts of a stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.5mg/mL, and performing ultrasonic treatment for 2.3 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1300r/min, and foaming for 50min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.07: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 25 parts of graphene in water, performing ultrasonic oscillation treatment for 15min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 45 ℃ for treatment, and performing freeze drying and crushing after 3h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

dispersing 35 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 13 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 1000r/min for 35min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

and step three, uniformly mixing the modified graphene obtained in the step one, the modified polytetrafluoroethylene fiber obtained in the step two, 20 parts of water and 2 parts of stabilizer to obtain the asphalt modifier.

In the third step, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed, and the steps are as follows: and (3) adding a plurality of positive charges to the modified polytetrafluoroethylene obtained in the step two by adopting a corona discharge method.

< comparative example 2>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 13 parts of carbon nano tubes, 6 parts of dopamine, 20 parts of vegetable oil polyol, 35 parts of polytetrafluoroethylene fibers and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 35 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 13 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 1000r/min for 35min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

step two, uniformly mixing the modified polytetrafluoroethylene fiber obtained in the step one, 6 parts of dopamine, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

In the second step, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed, and the method specifically comprises the following steps: and (3) adding a plurality of positive charges to the modified polytetrafluoroethylene obtained in the step (A) by adopting a corona discharge method.

< comparative example 3>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 13 parts of carbon nanotubes, 6 parts of dopamine, 20 parts of vegetable oil polyol, 35 parts of polytetrafluoroethylene fibers and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 25 parts of graphene in water, performing ultrasonic oscillation treatment for 15min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 45 ℃ for treatment, and performing freeze drying and crushing after 3h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

dispersing 35 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 13 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 1000r/min for 35min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

step three, uniformly mixing the modified graphene obtained in the step one, the modified polytetrafluoroethylene fiber obtained in the step two, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

In the third step, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed, and the steps are as follows: and D, adding a plurality of positive charges on the modified polytetrafluoroethylene fibers obtained in the step two by adopting a corona discharge method.

< comparative example 4>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 13 parts of carbon nano tubes, 20 parts of vegetable oil polyol, 35 parts of polytetrafluoroethylene fibers and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.5mg/mL, and performing ultrasonic treatment for 2.3 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1300r/min, and foaming for 50min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.07: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 35 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 13 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 1000r/min for 35min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

step two, uniformly mixing the graphene, the modified polytetrafluoroethylene fiber obtained in the step one, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

In the second step, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed, and the method specifically comprises the following steps: and (3) adding a plurality of positive charges to the modified polytetrafluoroethylene fibers obtained in the step one by adopting a corona discharge method.

< comparative example 5>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 13 parts of carbon nanotubes, 6 parts of dopamine, 20 parts of vegetable oil polyol, 35 parts of polytetrafluoroethylene fibers and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.5mg/mL, and performing ultrasonic treatment for 2.3 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1300r/min, and foaming for 50min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.07: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 35 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 13 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 1000r/min for 35min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

step two, uniformly mixing graphene, the modified polytetrafluoroethylene fiber obtained in the step one, 6 parts of dopamine, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

In the second step, the modified polytetrafluoroethylene fiber is subjected to electret treatment before being mixed with the modified graphene, and the method specifically comprises the following steps: and (3) adding a plurality of positive charges to the modified graphene obtained in the step one by adopting a corona discharge method.

< comparative example 6>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 13 parts of carbon nanotubes, 6 parts of dopamine, 20 parts of vegetable oil polyol and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.5mg/mL, and performing ultrasonic treatment for 2.3 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1300r/min, and foaming for 50min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.07: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 25 parts of graphene in water, performing ultrasonic oscillation treatment for 15min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 45 ℃ for treatment, and performing freeze drying and crushing after 3h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

step two, uniformly mixing the modified graphene obtained in the step one, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

< comparative example 7>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 13 parts of carbon nanotubes, 6 parts of dopamine, 20 parts of vegetable oil polyol, 35 parts of polytetrafluoroethylene fibers and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.5mg/mL, and performing ultrasonic treatment for 2.3 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1300r/min, and foaming for 50min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.07: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 25 parts of graphene in water, performing ultrasonic oscillation treatment for 15min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 45 ℃ for treatment, and performing freeze drying and crushing after 3h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

dispersing 35 parts of polytetrafluoroethylene fibers in absolute ethyl alcohol, adding 13 parts of carbon nano tubes into the absolute ethyl alcohol under stirring, stirring at the rotating speed of 1000r/min for 35min, and performing vacuum filtration until the absolute ethyl alcohol is completely volatilized to obtain modified polytetrafluoroethylene fibers;

step three, uniformly mixing the modified graphene obtained in the step one, the modified polytetrafluoroethylene fiber obtained in the step two, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

< comparative example 8>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 13 parts of carbon nanotubes, 6 parts of dopamine, 20 parts of vegetable oil polyol, 35 parts of polytetrafluoroethylene fibers and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.5mg/mL, and performing ultrasonic treatment for 2.3 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1300r/min, and foaming for 50min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.07: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 25 parts of graphene in water, performing ultrasonic oscillation treatment for 15min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 45 ℃ for treatment, and performing freeze drying and crushing after 3h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

step two, uniformly mixing the modified graphene obtained in the step one, 13 parts of carbon nano tubes, 35 parts of polytetrafluoroethylene fibers, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

In the second step, the polytetrafluoroethylene fibers are subjected to electret treatment before being mixed, and the method specifically comprises the following steps: and (3) adding a plurality of positive charges on the polytetrafluoroethylene fibers by adopting a corona discharge method.

< comparative example 9>

The invention provides an asphalt modifier, which comprises the following raw materials in parts by weight: 25 parts of graphene, 6 parts of dopamine, 20 parts of vegetable oil polyol, 35 parts of polytetrafluoroethylene fiber and 2 parts of stabilizer.

Wherein the stabilizer is sulfur.

The graphene is pretreated, and specifically comprises the following steps:

s1, dispersing graphene in an ethanol solution, controlling the mass concentration of the graphene to be 0.5mg/mL, and performing ultrasonic treatment for 2.3 hours to obtain a colloidal solution;

s2, adding a surfactant into the colloidal solution, stirring the colloidal solution at a stirring speed of 1300r/min, and foaming for 50min to obtain a foam suspension, wherein the weight ratio of the added amount of the surfactant to the graphene in the colloidal solution is 0.07: 1;

and S3, freeze-drying and crushing the foam suspension to obtain the pretreated graphene.

The surfactant in step S2 is sodium dodecyl sulfate.

A preparation process of an asphalt modifier comprises the following steps:

step one, dispersing 25 parts of graphene in water, performing ultrasonic oscillation treatment for 15min, adding dopamine hydrochloride, then placing the mixture in an ultrasonic oscillator at the temperature of 45 ℃ for treatment, and performing freeze drying and crushing after 3h to obtain modified graphene; wherein the weight ratio of dopamine hydrochloride to graphene is 0.2: 1;

step two, uniformly mixing the modified graphene obtained in the step one, polytetrafluoroethylene fibers, 20 parts of vegetable oil polyol and 2 parts of stabilizer to obtain the asphalt modifier.

The polytetrafluoroethylene fiber is also subjected to electret treatment before being mixed, and the electret treatment method specifically comprises the following steps: a plurality of positive charges are added to the polytetrafluoroethylene by a corona discharge method.

< test example >

The asphalt modifiers prepared in examples 1-3 and comparative examples 1-9 are respectively prepared into 12 asphalt compositions according to the following methods, and the preparation method specifically comprises the following steps:

according to the weight portion, 95 weight portions of asphalt matrix is heated to 140-160 ℃ (the asphalt matrix is road petroleum asphalt in the prior art, the penetration at 25 ℃ is 75dmm, the softening point is 47.5 ℃), then 5 weight portions of the asphalt modifier are added into the asphalt matrix, the mixture is stirred for 30min at the rotating speed of 4000rpm, then the mixture is sent into a high shear machine for shearing treatment for 40-60 min, the shearing speed is 3000-5000 r/min, the shearing temperature is 170-190 ℃, and then the mixture develops for 20-30 min at the rotating speed of 200-300 r/min and the temperature of 130-150 ℃, so that the asphalt composition is obtained. Meanwhile, the asphalt matrix is taken as a control group, the asphalt matrix is directly processed according to the process steps in the preparation method, and the asphalt composition of the control group is obtained by heating, shearing and developing.

The asphalt compositions of examples 1 to 3, comparative examples 1 to 9 and the control were subjected to aging treatment, respectively, and the aging treatment method was:

heating the asphalt composition to 135 ℃, after melting, spreading the asphalt composition in a sample container with the diameter of 150mm, wherein the thickness of the asphalt composition is controlled to be 3.2mm, and the dosage of the asphalt composition is 50-50.5 g; then placing the sample containing vessel in a film heating oven with the temperature of 160 ℃, and heating and aging for 5 hours to obtain a thermally aged asphalt sample;

placing the heated and aged asphalt sample at an internal temperature of 60 ℃ and an ultraviolet radiation intensity of 800 mu W/cm²In an LHX-205 intelligent numerical control photo-thermal aging box of a straight-tube ultraviolet high-pressure mercury lamp light source with the power of 500W, photo-aging is continued for 6d to obtain an asphalt composition after photo-oxidative aging; the distance between the sample and the ultraviolet high-pressure mercury lamp during the photoaging was 45 cm.

And (3) performance testing:

respectively carrying out conventional performance tests on the asphalt compositions subjected to photo-oxidative aging on the asphalt compositions of examples 1-3, comparative examples 1-9 and a control group (before aging); the test results are shown in table 1.

TABLE 1 results of conventional Performance testing of asphalt compositions before and after photo-oxidative aging

Remarking: penetration, softening point and ductility test methods refer to road engineering asphalt and asphalt mixture test procedure (JTJ052-2000) of Ministry of transportation;

residual penetration ratio (after-aging penetration/before-aging penetration)

As can be seen from the data in Table 1, the residual penetration before and after aging of the asphalt compositions prepared from the asphalt modifiers prepared in examples 1 to 3 is obviously higher than that of comparative examples 1 to 9 and a control group, and the higher the residual penetration is, the lower the aging degree of the asphalt subjected to the photo-oxidation aging treatment is;

the increase of the softening point increment before and after aging of the asphalt composition prepared by the asphalt modifier prepared in the embodiment 1-3 is obviously lower than that of the comparative examples 1-9 and the control group, and the lower the softening point increase is, the lower the aging degree of the asphalt subjected to the photo-oxidation aging treatment is;

the ductility reduction amplitude of the asphalt composition prepared by the asphalt modifier prepared in the embodiment 1-3 before and after aging is obviously lower than that of the comparative examples 1-9 and the control group, and the lower the softening point increase is, the lower the aging degree of the asphalt subjected to photo-oxidation aging treatment is;

therefore, the raw material proportion of the asphalt modifier is shown, and the preparation process comprises the steps of pretreating graphene, adsorbing dopamine on the pretreated graphene in advance, adsorbing carbon nano tubes on polytetrafluoroethylene in advance and performing electret treatment on the polytetrafluoroethylene before final mixing, so that the asphalt modifier has the effect of improving the anti-oxidation and anti-aging performance of asphalt.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable to various fields of endeavor for which the invention may be embodied with additional modifications as would be readily apparent to those skilled in the art, and the invention is therefore not limited to the details given herein and to the embodiments shown and described without departing from the generic concept as defined by the claims and their equivalents.