Preparation method of half-crack high-molecular polymer asphalt warm-mixing modifier

Abstract

The invention discloses a preparation method of a half-crack high-molecular polymer asphalt warm-mixing modifier, and relates to the technical field of asphalt modifiers, the preparation method comprises the following steps: firstly, adding an environment-friendly oil component into a reaction kettle, heating under normal pressure, and keeping continuous stirring in a dispersion disc to obtain a base oil component; then adding high-molecular polymer particles into the base oil component, carrying out cracking reaction, simultaneously lifting the dispersion disc up and down to uniformly mix the materials in the reaction kettle, and stirring until the high-molecular polymer particles and the base oil component are mixed and dissolved to obtain a mixture; sequentially adding resin and auxiliaries into the mixture, stirring until all the components are fully mixed and dissolved, cooling, and packaging a finished product or cooling to normal temperature, crushing and bagging to obtain the warm-mixing modifier. According to the preparation method of the warm mixing modifier, the modified asphalt mixture can be prepared on site, the asphalt consumption is reasonably controlled, the separation of the asphalt mixture under long-distance transportation and storage is avoided, the emission of asphalt smoke is greatly reduced, the comprehensive cost is reduced, and the construction environment is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of asphalt modifier, in particular to a preparation method of semi-split high molecular polymer asphalt warm-mix modifier. BACKGROUND

[0002] The existing warm-mix technology mainly includes three types: solvent dilution type, surface active type and foaming warm-mix technology. The three methods can achieve the effect of warm-mix, but the performance of the base asphalt is not significantly improved, and even the performance index of the asphalt is reduced, thereby affecting the performance of the warm-mix asphalt mixture. The main principle of the solvent dilution type is to add dilution solvents or oil fractions such as naphthenic oil and aromatic oil to the asphalt to dilute the asphalt and reduce the mixing temperature. The surface active type mainly reduces the intermolecular force and lubricity of the asphalt to reduce the requirement of the asphalt on temperature, and improves the wrapping degree of the asphalt on the stone through directional adsorption to achieve the effect of warm-mix. The foaming warm-mix technology is to inject cold water into high-temperature asphalt through hollow zeolite or other means to form water vapor bubbles, so that the volume of the asphalt is expanded and the viscosity is reduced to form a balanced and stable mixture of asphalt and water vapor bubbles to form foamed asphalt, thereby achieving the effect of warm-mix. Although the three methods can achieve the effect of warm-mix, the performance of the base asphalt is not significantly improved, and even the performance index of the asphalt is reduced, thereby affecting the overall performance of the warm-mix asphalt mixture.

[0003] In the prior art, the dilution type warm-mix agent changes the original component content of the asphalt by adding oil fractions, which is equivalent to changing the low-grade asphalt into high-grade asphalt through fine tuning, mainly manifested by the increase of penetration and ductility, and the unchanged or reduced softening point, thereby reducing the requirement of the asphalt on temperature, and the high-temperature performance of the asphalt mixture is also relatively reduced, mainly reflected in the decrease of anti-rutting times. The surface active type basically does not change the performance of the asphalt and the asphalt mixture, but the cost is high, and the cost of the finished asphalt mixture is greatly affected, so it is difficult to be widely used unless special requirements are met. The foaming technology has high operation difficulty because it needs to form a blended stable high-temperature foamed asphalt with water vapor bubbles and asphalt, and it cannot be stored for a long time, which increases the operation difficulty of production and construction. In addition, the existing warm-mix modifier does not significantly improve the performance of the asphalt mixture after achieving the effect of warm-mix, and the performance of the modified asphalt mixture is not improved but decreased in the area with long construction operation time and large environmental impact, which is not suitable for use in highland and cold regions, and is easy to cause waste of asphalt mixture. Therefore, it is urgent to propose a preparation method of semi-split high molecular polymer asphalt warm-mix modifier, which can significantly reduce the mixing temperature and enhance the road performance of the asphalt and the mixture. SUMMARY

[0004] The application aims to provide a preparation method of semi-split high molecular polymer asphalt warm modification agent to solve the problem that the asphalt warm modification agent in the prior art is difficult to reduce the mixing temperature of asphalt mixture and has no obvious performance improvement effect on the asphalt mixture.

[0005] To achieve the above-mentioned purpose, the application provides the following technical scheme: a preparation method of semi-split high molecular polymer asphalt warm modification agent, specifically comprising the following steps:

[0006] S1, 20-50 parts of environmentally friendly oil are added to a reaction kettle, heated to 130-150 DEG C under normal pressure, and the dispersion disc is continuously stirred to obtain a base oil;

[0007] S2, 10-20 parts of high molecular polymer particles are added to the base oil, the reaction kettle temperature is controlled at 130-150 DEG C for cracking reaction, and the dispersion disc is pulled up and down to mix the materials in the reaction kettle uniformly, and the high molecular polymer particles are mixed with the base oil to obtain a mixture;

[0008] S3, the temperature of the mixture is reduced to 80-100 DEG C, then 3-10 parts of resin and 5-20 parts of auxiliary are added to the mixture in turn, and the mixture is stirred until all components are fully mixed, and then packaged or cooled to room temperature and broken into bags after cooling to obtain a warm modification agent.

[0009] Further, the environmentally friendly oil in S1 is at least two of aromatic oil, naphthenic oil and recycled oil.

[0010] Further, the stirring speed of the dispersion disc in S1 is set to 400-500 r / min.

[0011] Further, the high molecular polymer particles in S2 are butadiene styrene rubber particles and / or SBS rubber particles.

[0012] Further, the stirring speed of the dispersion disc in S2 is set to 500-600 r / min.

[0013] Further, the resin in S3 is at least one of solid resin, petroleum resin and rosin resin.

[0014] Further, the auxiliary in S3 is at least two of surfactant, ultraviolet absorber, functional auxiliary and carbon black powder.

[0015] The application further discloses a semi-split high molecular polymer asphalt warm modification agent prepared by the preparation method.

[0016] Compared with the prior art, the preparation method of semi-split high molecular polymer asphalt warm modification agent has the following beneficial effects:

[0017] (1) The warm-mix modifier prepared by the application has obvious warm-mix effect, and the comprehensive performance of the asphalt mixture is obviously better than that before modification, which can reduce the production, paving and rolling temperature of the asphalt mixture by 30-40℃ on average, significantly reduce the construction temperature, can be used in highland and high-cold area, effectively reduce fuel consumption, and meet the green environmental protection requirements.

[0018] (2) The warm-mix modifier prepared by the high-temperature physical mixing technology adopts the "half-split" technology to process the high-molecular polymer, plays a warm-mix role in the early stage, and plays a polymer modification and enhancement role in the later stage, overcomes the problem of insufficient or decreased performance of the asphalt mixture caused by the traditional warm-mix agent, and has the dual functions of warm-mix and modification.

[0019] (3) The warm-mix modifier prepared by the application can realize on-site preparation of the modified asphalt mixture, avoids segregation of the asphalt mixture caused by long-distance transportation and storage, can reasonably control the amount of asphalt, greatly reduces the emission of asphalt smoke, reduces the comprehensive cost, and improves the construction environment.

[0020] (4) The resin and the surfactant in the warm-mix modifier synergistically form a three-dimensional network structure, which can significantly improve the high-temperature stability, water damage resistance and low-temperature crack resistance of the asphalt mixture, reduce the occurrence of diseases such as rut, pit and crack of the road surface, and improve the comprehensive performance of the road.

[0021] (5) By adding a functional additive in the warm-mix modifier, the ultraviolet aging speed of the asphalt mixture is effectively slowed down, and the service life of the road surface is prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0023] Figure 1 A preparation method flowchart of a semi-split high-molecular polymer asphalt warm-mix modifier provided by the embodiments of the present application. DETAILED DESCRIPTION

[0024] In order to make those skilled in the art better understand the technical solutions of the present application, the technical solutions provided by the present application will be described in detail below in combination with the embodiments, but they should not be understood as limiting the scope of protection of the present application. The present application will be further described in detail below in combination with the drawings.

[0025] Example 1:

[0026] Please refer toFigure 1 The application relates to a preparation method of a semi-split high-molecular polymer asphalt warm modification agent.

[0027] S1, 20-50 parts of environment-friendly oil are added into a reaction kettle, heated to 130-150 DEG C under normal pressure, and a dispersing disc is kept to continuously stir, so that a base oil is obtained;

[0028] The environment-friendly oil is at least two of aromatic oil, naphthenic oil and recycled oil; and the stirring speed of the dispersing disc is set to 400-500 r / min.

[0029] Specifically, 20-50 parts of environment-friendly oil such as aromatic oil, naphthenic oil and recycled oil are added into a reaction kettle, heated to 130-150 DEG C under normal pressure, and a dispersing disc is kept to continuously stir at a dispersing speed of 400 r / min, so that a base oil is obtained.

[0030] S2, 10-20 parts of high-molecular polymer particles are added into the base oil, a cracking reaction is carried out at a temperature of 130-150 DEG C, a dispersing disc is pulled up and down to make the materials in the reaction kettle uniformly mixed, and the high-molecular polymer particles are mixed with the base oil until a mixture is obtained;

[0031] The high-molecular polymer particles are SBS rubber particles and / or butadiene styrene rubber particles; and the stirring speed of the dispersing disc is set to 500-600 r / min.

[0032] Specifically, 10-20 parts of butadiene styrene rubber particles and SBS rubber particles are sequentially and slowly added into the base oil, a mixing cracking reaction is carried out at a temperature of 130-150 DEG C, the stirring speed of the dispersing disc is set to 600 r / min, the dispersing disc is pulled up and down to control the cracking depth, the materials in the reaction kettle are fully mixed and uniformly heated, the high-molecular polymer particles are mixed with the base oil until the cracking is completed, and the cracking product is in a dissolved and mixed state, so that a mixture is obtained.

[0033] S3, the temperature of the mixture is reduced to 80-100 DEG C, then 3-10 parts of resin and 5-20 parts of an additive are sequentially added into the mixture, all components are fully mixed, and the product is packaged after cooling or is bagged after being broken and cooled to normal temperature, so that a warm modification agent is obtained.

[0034] The resin is at least one of solid resin, petroleum resin and pine resin; and the additive is at least two of a surfactant, an ultraviolet absorber, carbon black powder and a functional additive.

[0035] The specific embodiment is that the temperature of the mixture is reduced to 80-100°C, then 3-10 parts of solid resin, petroleum resin, rosin resin and 5-20 parts of surfactant, functional aid, ultraviolet absorber, carbon black powder are sequentially added to the mixture, the relative temperature is dispersed for 1 h, stirring is performed until all components are fully mixed, finally the finished product is packaged or cooled to room temperature and broken into bags, to obtain the warm-mix modifier.

[0036] Example two:

[0037] Please refer to Table 1, this embodiment provides a technical solution on the basis of example one: a semi-cracked high molecular polymer asphalt warm-mix modifier, which presents a black liquid appearance, is compatible with the color of asphalt base material; the density at 25°C is controlled at 0.95-0.98 g / cm³, which is close to the density of conventional asphalt, and is beneficial to uniform mixing; the flash point is ≥200°C to ensure safety in high-temperature construction; the viscosity is lower than 300 mPa·s (25°C) to guarantee low-temperature mixing fluidity, and the water content is ≤0.5%, which effectively avoids air bubble defects in the mixing process; when used as a warm-mix modifier, the asphalt internal mixing method is adopted, and the modifier is directly added at a proportion of 4%-6% of the mass of asphalt, which is simple and efficient.

[0038] The warm-mix modifier realizes the goal of reducing the mixing temperature of asphalt while maintaining or improving the road performance through density matching, low viscosity design, high flash point guarantee and accurate addition proportion, which meets the dual needs of energy saving and emission reduction and construction efficiency of warm-mix modification technology.

[0039] Table 1 Comprehensive performance of semi-cracked high molecular polymer asphalt warm-mix modifier

[0040]

[0041] Example three:

[0042] Please refer to Tables 2-5, this embodiment provides a technical solution on the basis of example one: performance test of warm-mix modified asphalt and warm-mix modified asphalt mixture:

[0043] Water stability test: immersion Marshall test and freeze-thaw splitting test should meet the following requirements:

[0044] (1) The immersion Marshall test uses test pieces that are mixed according to temperature control and aged in an oven at 145°C for 2 h, and then executed according to standard JTG E20.

[0045] (2) The freeze-thaw splitting test uses test pieces that are mixed according to temperature control and aged in an oven at 145°C for 2 h, and then executed according to standard JTGE20.

[0046] (3) The water stability of warm mix modified asphalt mixture is tested by immersion Marshall test and freeze-thaw splitting test. The technical requirements of residual stability and residual strength ratio shall comply with the provisions of Table 2.

[0047] Table 2 Technical requirements for testing the water stability of warm mix modified asphalt mixture

[0048]

[0049] Low temperature bending test: The low temperature bending test shall comply with the following requirements:

[0050] (1) The beam specimen is processed according to the standard JTG E20 after the well-mixed specimen is controlled at temperature and aged in the oven at 145°C for 2h. The size shall comply with the provisions of T0715.

[0051] (2) The low temperature performance of warm mix modified AC-20, AC-16 and AC-13 asphalt mixture shall be verified. The technical requirements shall comply with the provisions of Table 3.

[0052] Table 3 Technical requirements for failure strain of warm mix modified asphalt mixture in low temperature bending test

[0053]

[0054] The warm mix modifier prepared in Example 1, and the competitive warm mix modifiers 1-3, are respectively mixed with the same base asphalt and aggregate at 140°C, the specimen is formed, and the Marshall stability, residual stability, freeze-thaw splitting strength ratio, rutting dynamic stability and other tests are carried out. The uniform dosage of the warm mix modifier is 4%; the oil-stone ratio is 4.6%, the modified asphalt temperature is 140°C, the mineral material heating temperature is 155°C, the mixing temperature is 145°C, the discharge temperature is 140°C, the dry mixing is 60s, the addition of asphalt mixing is 60s, the addition of mineral powder mixing is 60s, the compaction temperature is 135-145°C, and the double-sided 75 times compaction. The rutting plate is calculated according to the actual density and compaction degree. Gradation: 10-15:5-10:3-5:0-3: mineral powder = 24:16:28:30:2.

[0055] In the initial modification stage, light oil, saturated components and surfactants are mainly used to reduce the intermolecular forces (such as intermolecular stress and molecular motion resistance) of asphalt molecules at a low temperature of 120-130°C, so as to enhance the molecular activity, so that the asphalt can achieve the mixing effect at a high temperature under a relatively low heating condition. Since the whole mixing temperature is reduced, the pore structure of the aggregate is significantly reduced at a temperature of 160-180°C, thereby reducing the absorption amount of the asphalt, and effectively reducing the use amount of a part of the asphalt; in the middle stage of asphalt mixing with the stone, for a period of time, part of the active molecules (polar functional groups) in the surfactant reacts with the stone in a similar complex reaction, and part of the surfactant reduces the surface tension of the asphalt, and the resin component combines with the surfactant and the effective molecules of the asphalt to form a three-dimensional network structure, so that the asphalt can be uniformly wrapped on the stone and improve the workability and ease of the mixture; in the later stage, through the rolling and cooling effect, the low-melting-point high-modulus polymer and the hot-melt resin in the original high-temperature liquid state are homogenized into a solid state, so as to improve the high-temperature stability, water resistance and other abilities of the asphalt mixture.

[0056] The test results are shown in Table 4: the test results show that, under the same mixing temperature (140°C), the modified agent prepared by the present application realizes the warm mixing effect of the 70# asphalt by 4% of the mixing amount and the optimized process parameters, and the performance indicators are significantly better than those of the competitive warm mixing agent, and even exceed the conventional hot mixing asphalt mixture mixed at a higher temperature, realizing the comprehensive improvement of the high-temperature stability, water stability and construction performance, fully proving the excellent warm mixing and modification double effects.

[0057] Table 4 Comparison table of performance parameters of asphalt and asphalt mixture modified by different modified agents

[0058]

[0059] The competitive modified agent and the semi-cracked high-molecular polymer asphalt warm mixing modifier prepared in Example 1 are respectively used to warm mix modify the 70# asphalt, and the results are shown in Table 5. The 70# asphalt using the semi-cracked high-molecular polymer asphalt warm mixing modifier is significantly better than the competitive modified asphalt and the ordinary 70# asphalt in the dynamic stability, residual stability, freeze-thaw splitting strength ratio and other key indicators (dynamic stability 1322 times / mm, residual stability 83%, freeze-thaw splitting strength ratio 80%), and meets the technical requirements of JTG F40-2004. The high-temperature stability, water stability and low-temperature crack resistance (bending failure strain 2856με) are excellent. At the same time, the warm mixing process reduces the discharge temperature to 145-155°C, and the energy-saving and environmental protection advantages are outstanding. In summary, the warm modified asphalt has comprehensive advantages in performance balance, environmental protection and cost-effectiveness, and is suitable for heavy-load traffic roads in high-temperature and rainy areas with high environmental protection requirements.

[0060] Table 5 No. 70 asphalt, SBS modified and semi-split high molecular polymer asphalt warm modified asphalt performance comparison analysis table

[0061]

[0062] In summary, the semi-split high molecular polymer asphalt warm modifier prepared by the present application uses light oil as a carrier for splitting high molecular polymers, and can slightly reduce the temperature without affecting the performance of the asphalt; by adjusting the molecular force and molecular motion state of the asphalt through the surface active ingredient, the temperature of the asphalt production, construction and other environments can be reduced without affecting the performance of the asphalt; by the high molecular polymer split to a certain extent, the asphalt is modified and enhanced, so as to achieve the purpose of both temperature reduction and modification; by adding resin components, the three-dimensional network structure of the hydrophilic and lipophilic groups of the surface active ingredient is formed, the asphalt coverage, adsorption capacity and later mixture pavement performance of the stone are improved; by other functional additives, the environmental resistance of the mixture to ultraviolet light is improved.

[0063] The above only describes some exemplary embodiments of the present application by way of illustration, and it is needless to say that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present application. Therefore, the above drawings and descriptions are illustrative in nature and should not be understood as limiting the scope of protection of the claims of the present application.

Claims

1. A method for preparing a semi-splitting polymeric asphalt warm-mix modifier, characterized in that, Specifically, the following steps are included: S1. Add 20-50 parts of environmentally friendly oil to the reactor, heat to 130-150°C under normal pressure, and keep stirring in the dispersion plate to obtain the base oil. S2. Add 10-20 parts of high molecular weight polymer particles to the base oil, control the temperature of the reactor at 130-150℃ to carry out the pyrolysis reaction, and at the same time, lift the dispersion plate up and down to make the material in the reactor mix evenly. Stir until the high molecular weight polymer particles and the base oil are miscible to obtain a mixture. S3. Reduce the temperature of the mixture to 80-100℃, then add 3-10 parts of resin and 5-20 parts of additives to the mixture in sequence, stir until all components are fully mixed, cool and package the finished product or cool to room temperature, crush and bag it to obtain the warm-mix modifier.

2. The method for preparing a semi-splitting polymeric asphalt warm-mix modifier according to claim 1, characterized in that, The environmentally friendly oil in S1 is divided into at least two types: aromatic oil, naphthenic oil, and recycled oil.

3. The preparation method of a semi-splitting polymeric asphalt warm-mix modifier according to claim 1, characterized in that, The stirring speed of the dispersion disc in S1 is set to 400-500 r / min.

4. The preparation method of a semi-splitting polymeric asphalt warm-mix modifier according to claim 1, characterized in that, The polymer particles in S2 are styrene-butadiene rubber particles and / or SBS rubber particles.

5. The method for preparing a semi-splitting polymeric asphalt warm-mix modifier according to claim 1, characterized in that, The stirring speed of the dispersion disc in S2 is set to 500-600 r / min.

6. The preparation method of a semi-splitting polymeric asphalt warm-mix modifier according to claim 1, characterized in that, The resin in S3 is at least one of solid resin, petroleum resin, and rosin resin.

7. The preparation method of a semi-splitting polymeric asphalt warm-mix modifier according to claim 1, characterized in that, The additive in S3 is at least two of the following: surfactant, ultraviolet absorber, functional additive, and carbon black powder.

8. A semi-splitting polymeric asphalt warm-mix modifier, characterized in that, It is prepared by the preparation method described in any one of claims 1-7.

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