High-elasticity, noise-reducing, soluble rubber powder modified asphalt and preparation method thereof

Abstract

A highly elastic, noise-reducing, soluble rubber powder-modified asphalt and its preparation method, belonging to the field of polymer materials technology, is composed of 25-35 parts of modified scrap tire rubber powder, 65-95 parts of base asphalt, 5-12 parts of modified sepiolite, 6-15 parts of modified diatomaceous earth, and 2-5 parts of a composite emulsifying solubilizer. The resulting highly elastic, noise-reducing, soluble rubber powder-modified asphalt has a needle penetration of 31.2-33.2 (25°C, 5s, 100g) / 0.1mm, a softening point of 92.7-93.5°C, an elongation of 34.3-35.6 (5°C, 5cm / min) / cm, a viscosity of 2.05-2.49 Pa·s at 180°C, a storage stability (segregation, 48-hour softening point difference) of 1.2-1.6°C, an elastic recovery rate of 91-94%, and a tire drop test noise level of 75-79dB.

Description

Technical Field

[0001] The invention relates to a high-elasticity, noise-reducing, solubility-modified rubber powder asphalt and a preparation method thereof, belonging to the technical field of polymer materials. Background Art

[0002] For the economy to develop, transportation must come first. The rapid development of road transportation in my country has promoted the rapid development of my country's economy. However, the rapid development of road transportation will cause a series of environmental problems, including noise pollution, vibration pollution, automobile consumables pollution, etc. The waste tires generated by road transportation contain a large amount of SBR, natural rubber and other materials that are beneficial to improving the performance of asphalt. Using waste tires as modifiers to improve the road performance of asphalt materials is a value-added recycling method. In order to reduce the negative impact of waste tires and driving noise and vibration on the environment, it is a practical solution to use the high elasticity and excellent mechanical properties of waste tires to improve the elasticity, durability, crack resistance and wear resistance of asphalt to reduce road noise and improve vehicle driving comfort.

[0003] Chinese patent CN107974091A discloses a high-viscosity rubber powder-modified asphalt material for noise-reducing and drainage pavement. The material is prepared, by weight, from 56-80 parts of base asphalt, 15-25 parts of waste rubber powder, 1-3 parts of thermoplastic elastomer, 1.5-6 parts of waste phosphate ester, 1-5 parts of thermoplastic resin, 1-5 parts of plasticizer, and 0.1-0.3 parts of crosslinker. The preparation method comprises premixing the waste rubber powder, thermoplastic elastomer, and waste phosphate ester to produce an asphalt modifier; heating the base asphalt, adding the asphalt modifier, then adding the thermoplastic resin and plasticizer, and continuing to stir and shear the mixture while maintaining the temperature; and finally, adding the crosslinker to produce the modified asphalt. The high-viscosity rubber powder-modified asphalt of this invention has a dynamic viscosity of over 60,000 Pa·s at 60°C, and exhibits excellent high-temperature stability, rutting resistance, and aging resistance. It is particularly suitable for paving in hot and humid summer areas, areas with large day-night temperature differences, or drainage-prone pavement. The high-viscosity rubber powder modified asphalt material obtained by this patent has a large amount of thermoplastic elastomer, thermoplastic resin, waste rubber powder and plasticizer added, but has better toughness. The obtained asphalt material only has hydrophobic properties, no drainage effect, and relatively poor noise reduction function.

[0004] Chinese patent CN101671144A discloses a rubber-modified asphalt and a preparation method thereof. The rubber-modified asphalt is made from the following raw materials in percentage by mass: 78-90% base asphalt, 9.1-21.5% scrap rubber powder, 0.4-0.8% retardant, and 0.08-0.12% stabilizer. The retardant is prepared by stirring rubber softening oil and diallyl phthalate at 120-140°C for 0.5-1.5 hours, and the stabilizer is prepared by stirring the accelerator tetrabutylthiuram monosulfide and an antioxidant at 65-75°C for 0.5-1 hour. However, the rubber-modified asphalt obtained in this patent still has significant problems such as insufficient elasticity, poor toughness, and unsatisfactory noise reduction.

[0005] From the above, we can see that the current rubber powder modified asphalt still has significant defects such as poor toughness, low elasticity, and poor noise reduction performance. Therefore, it is urgent to develop an asphalt product with high elasticity, high toughness and good noise reduction performance to meet the stringent requirements of the current rapidly developing transportation industry for pavement materials. Summary of the Invention

[0006] In view of the deficiencies in the above-mentioned prior art, the present invention provides a highly elastic and noise-reducing soluble rubber powder modified asphalt and a preparation method thereof, to achieve the following invention objectives: to prepare rubber powder modified asphalt with high elasticity, good toughness and excellent noise reduction performance.

[0007] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0008] A high-elasticity, noise-reducing, soluble rubber powder modified asphalt and a preparation method thereof. The specific formula of the high-elasticity, noise-reducing, soluble rubber powder modified asphalt is, in parts by weight:

[0009] 25~35 parts of modified waste tire rubber powder,

[0010] 65~95 parts of base asphalt,

[0011] 5~12 parts of modified sepiolite,

[0012] 6~15 parts of modified diatomaceous earth,

[0013] 2~5 parts of composite emulsifying solubilizer;

[0014] The matrix asphalt is No. 70 asphalt or No. 90 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction";

[0015] The composite emulsifying solubilizer is composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate;

[0016] The mass ratio of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate is 25-35:15-40:1-4;

[0017] The preparation method of the high-elasticity and noise-reducing soluble rubber powder modified asphalt comprises the steps of preparing modified waste tire rubber powder, preparing modified sepiolite, preparing modified diatomaceous earth, preparing soluble rubber powder modified asphalt, etc.

[0018] The following are further improvements to the above technical solution:

[0019] Step 1: Preparation of modified waste tire rubber powder

[0020] After grinding the waste tire rubber powder into a powder of 40-100 mesh, the powder is added to a high-pressure reactor, and then polydimethyldiallylammonium chloride, N-aminoethylpiperazine, and anhydrous ethanol are added to the reactor. The stirring is started, and the stirring rate is controlled at 500-850 rpm. The temperature is raised to 100-140° C., and nitrogen is introduced and pressurized to 0.3-0.8 MPa. The above pressure, temperature, and stirring rate are maintained, and the reaction is carried out for 3-6 hours. After the pressure is released and the temperature is lowered to room temperature, the material is discharged and filtered. The filtered solid is dried at 40-60° C. for 6-10 hours to obtain the modified waste tire rubber powder.

[0021] The mass ratio of the waste tire rubber powder, polydimethyldiallylammonium chloride, N-aminoethylpiperazine and anhydrous ethanol is 25-40:2-6:5-10:80-120.

[0022] Step 2: Preparation of modified sepiolite

[0023] Mix sepiolite, isopropyl distearate acyloxyaluminate, tetramethyl silicate, and p-xylene in a mass ratio of 25-50:2-3.5:3-6:120-145, control the temperature at 135-150° C., stir at 400-650 rpm, reflux for 4-7 hours, filter, wash the filtered solid with anhydrous ethanol 2-4 times, and dry at 60-90° C. for 1-4 hours to obtain a modified sepiolite.

[0024] The particle size of the sepiolite is 0.1-3 μm.

[0025] Step 3: Preparation of modified diatomaceous earth

[0026] Diatomaceous earth, bis-[γ-(triethoxysilyl)propyl] tetrasulfide, oleic acid diethanolamide, and toluene are mixed in a mass ratio of 15-40:2-6:1-5:75-125, the mixture is refluxed at 85-110° C. and a stirring rate of 330-650 rpm for 3-8 hours, and the mixture is filtered. The filtered solid is dried at 90-120° C. for 2-5 hours to obtain modified diatomaceous earth.

[0027] The particle size of the diatomaceous earth is 0.1-9 μm.

[0028] Step 4: Preparation of soluble rubber powder modified asphalt

[0029] According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, first put the base asphalt and the composite emulsifying solubilizer into the mixing kettle and heat it to 150~180℃. After the base asphalt is melted, start stirring and control the stirring rate at 800~1200 rpm. After stirring and mixing for 30~50 minutes, add the modified waste tire rubber powder, modified sepiolite and modified diatomaceous earth, and continue stirring and mixing. After the temperature stabilizes at 150~180℃ again, start the high-speed shear dispersing paddle and control the shear rate at 5000~9000 rpm. After shear dispersion treatment for 90~140 minutes, stop stirring and shear dispersion, and then cool to 75~90℃ before discharging. After discharging, continue to air-cool to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

[0030] Compared with the prior art, the present invention achieves the following beneficial effects:

[0031] 1. In the present invention, the surface of waste tire rubber powder is modified by using polydimethyldiallyl ammonium chloride and N-aminoethylpiperazine. The polydimethyldiallyl ammonium chloride plays a role in dispersing, emulsifying and activating the surface, thereby increasing the affinity of the surface of the waste tire rubber powder particles with anhydrous ethanol, promoting the uniformity of the dispersion of the waste tire rubber powder particles in anhydrous ethanol, and ensuring good contact between the surface of the rubber powder particles and N-aminoethylpiperazine. Furthermore, the amino group of N-aminoethylpiperazine can fully catalyze the breaking of the chemical bonds containing sulfur elements in the rubber powder particles, significantly reducing the polarity of the surface of the rubber powder particles, thereby facilitating the increase of the solubility of the rubber powder particles in the matrix asphalt, and obtaining a more uniform and stable solubility of the rubber powder modified asphalt;

[0032] 2. In the present invention, sepiolite is modified with isopropyl distearate acyloxyaluminate and tetramethyl silicate, which reduces the surface polarity of the sepiolite and increases the hydrophobicity of the sepiolite itself, thereby promoting the uniformity of the dispersion of the sepiolite in the matrix asphalt, which is beneficial to improving the strengthening and toughening effect of the sepiolite on the asphalt. In addition, the microporous structure of the sepiolite itself with a large surface area has a very significant effect on improving the noise reduction performance of the matrix asphalt. The uniform dispersion of the sepiolite in the matrix asphalt can ensure that the noise reduction performance of the sepiolite is fully exerted.

[0033] 3. In the present invention, diatomaceous earth is modified by adding bis-[γ-(triethoxysilyl)propyl]tetrasulfide and oleic acid diethanolamide. Under the dispersing effect of oleic acid diethanolamide, the diatomaceous earth particles fully react with bis-[γ-(triethoxysilyl)propyl]tetrasulfide, and the surface hydrophilicity is changed to surface hydrophobicity, which ensures the compatibility and dispersion uniformity of diatomaceous earth with matrix asphalt. Moreover, the sulfur element contained in bis-[γ-(triethoxysilyl)propyl]tetrasulfide can undergo a certain degree of vulcanization and cross-linking reaction with the unsaturated bonds on the surface of the modified scrap tire rubber powder, which not only promotes the affinity of diatomaceous earth and scrap tire rubber powder particles, but also increases the hydrophobicity of the surface of the scrap tire rubber powder particles, further promoting the compatibility of diatomaceous earth and scrap tire rubber powder particles with matrix asphalt and the dispersion uniformity of the two in the matrix asphalt, thereby improving the comprehensive performance of the solubility rubber powder modified asphalt;

[0034] 4. The present invention uses a composite emulsifying solubilizer composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethylamine, and disodium lauroamphodiacetate to fully emulsify the base asphalt, reduce the viscosity of the asphalt at high temperatures, improve the high-temperature fluidity of the asphalt, and promote the solubility of modified scrap tire rubber particles, modified sepiolite, and modified diatomaceous earth in the asphalt, so that the above components and the base asphalt form a uniform and stable single phase, thereby obtaining a soluble rubber powder modified asphalt with high elasticity and noise reduction performance;

[0035] 5. The high-elasticity, noise-reducing, soluble rubber powder modified asphalt obtained by the present invention has a needle penetration of 31.2~33.2 (25℃, 5s, 100g) / 0.1mm, a softening point of 92.7~93.5℃, an elongation of 34.3~35.6 (5℃, 5cm / min) / cm, a viscosity of 2.05~2.49Pa·s at 180℃, a storage stability (segregation, 48-hour softening point difference) of 1.2~1.6℃, an elastic recovery rate of 91~94%, and a tire drop test noise of 75~79dB. DETAILED DESCRIPTION

[0036] The preferred embodiments of the present invention are described below. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0037] Example 1: Preparation method of high-elasticity and noise-reducing soluble rubber powder modified asphalt

[0038] Step 1: Preparation of modified waste tire rubber powder

[0039] After grinding the waste tire rubber powder into 80 mesh powder, the powder was added to a high-pressure reactor, and polydimethyldiallylammonium chloride, N-aminoethylpiperazine, and anhydrous ethanol were added to the reactor. The stirring was started, and the stirring rate was controlled at 800 rpm. The temperature was raised to 130° C., and nitrogen was introduced and pressurized to 0.6 MPa. The above pressure, temperature, and stirring rate were maintained. After reacting for 5 hours, the pressure was released and the temperature was lowered to room temperature. The material was discharged and filtered. The filtered solid was dried at 55° C. for 8 hours to obtain the modified waste tire rubber powder.

[0040] The mass ratio of the waste tire rubber powder, polydimethyldiallyl ammonium chloride, N-aminoethylpiperazine and anhydrous ethanol is 30:5:8:110.

[0041] Step 2: Preparation of modified sepiolite

[0042] Sepiolite, isopropyl distearate acyloxyaluminate, tetramethyl silicate, and p-xylene were mixed in a mass ratio of 40:3:5:135, and the mixture was refluxed at 145°C and a stirring rate of 550 rpm for 5 hours. The mixture was then filtered, and the filtered solid was washed three times with anhydrous ethanol and dried at 80°C for 3 hours to obtain a modified sepiolite.

[0043] The particle size of the sepiolite is 2 μm.

[0044] Step 3: Preparation of modified diatomaceous earth

[0045] Diatomaceous earth, bis-[γ-(triethoxysilyl)propyl] tetrasulfide, oleic acid diethanolamide, and toluene were mixed in a mass ratio of 30:5:4:120, and the mixture was refluxed at 105° C. and a stirring rate of 560 rpm for 6 hours. The mixture was filtered, and the filtered solid was dried at 110° C. for 4 hours to obtain modified diatomaceous earth.

[0046] The particle size of the diatomaceous earth is 7 μm.

[0047] Step 4: Preparation of soluble rubber powder modified asphalt

[0048] The specific formula of the high-elasticity and noise-reducing soluble rubber powder modified asphalt is as follows, in parts by weight:

[0049] 30 parts of modified waste tire rubber powder,

[0050] 85 parts of base asphalt,

[0051] 11 parts of modified sepiolite,

[0052] 10 parts of modified diatomaceous earth,

[0053] 3 parts of composite emulsifying solubilizer;

[0054] The matrix asphalt is No. 70 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction";

[0055] The composite emulsifying solubilizer is composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate;

[0056] The mass ratio of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate is 28:35:3;

[0057] According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, first put the base asphalt and the composite emulsifying solubilizer into the mixing kettle and heat it to 170°C. After the base asphalt is melted, start stirring and control the stirring rate at 1100 rpm. After stirring and mixing for 45 minutes, add the modified waste tire rubber powder, modified sepiolite and modified diatomaceous earth, and continue stirring and mixing. After the temperature stabilizes at 165°C again, start the high-speed shear dispersing paddle and control the shear rate at 7500 rpm. After shear dispersion treatment for 120 minutes, stop stirring and shear dispersion, and then cool to 80°C before discharging. After discharging, continue to air-cool to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

[0058] Example 2: Preparation method of high-elasticity and noise-reducing soluble rubber powder modified asphalt

[0059] Step 1: Preparation of modified waste tire rubber powder

[0060] After grinding the waste tire rubber powder into a 40-mesh powder, the powder was added to a high-pressure reactor. Then, polydimethyldiallylammonium chloride, N-aminoethylpiperazine, and anhydrous ethanol were added to the reactor. The stirring was started and the stirring rate was controlled at 500 rpm. The temperature was raised to 100° C. and nitrogen was introduced to increase the pressure to 0.3 MPa. The above pressure, temperature, and stirring rate were maintained. After reacting for 3 hours, the pressure was released and the temperature was lowered to room temperature. The material was discharged and filtered. The filtered solid was dried at 40° C. for 6 hours to obtain the modified waste tire rubber powder.

[0061] The mass ratio of the waste tire rubber powder, polydimethyldiallyl ammonium chloride, N-aminoethylpiperazine and anhydrous ethanol is 25:2:5:80.

[0062] Step 2: Preparation of modified sepiolite

[0063] Sepiolite, isopropyl distearate acyloxyaluminate, tetramethyl silicate, and p-xylene were mixed in a mass ratio of 25:2:3:120, and the mixture was refluxed at 135°C and a stirring rate of 400 rpm for 4 hours. The mixture was then filtered, and the filtered solid was washed twice with anhydrous ethanol and dried at 60°C for 1 hour to obtain a modified sepiolite.

[0064] The particle size of the sepiolite is 0.1 μm.

[0065] Step 3: Preparation of modified diatomaceous earth

[0066] Diatomaceous earth, bis-[γ-(triethoxysilyl)propyl] tetrasulfide, oleic acid diethanolamide, and toluene were mixed in a mass ratio of 15:2:1:75, and the mixture was refluxed at 85°C and a stirring rate of 330 rpm for 3 hours. The mixture was then filtered, and the filtered solid was dried at 90°C for 2 hours to obtain modified diatomaceous earth.

[0067] The particle size of the diatomaceous earth is 0.1 μm.

[0068] Step 4: Preparation of soluble rubber powder modified asphalt

[0069] The specific formula of the high-elasticity and noise-reducing soluble rubber powder modified asphalt is as follows, in parts by weight:

[0070] 25 parts of modified waste tire rubber powder,

[0071] 65 parts of base asphalt,

[0072] 5 parts of modified sepiolite,

[0073] 6 parts of modified diatomaceous earth,

[0074] 2 parts of composite emulsifying solubilizer;

[0075] The matrix asphalt is No. 90 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction";

[0076] The composite emulsifying solubilizer is composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate;

[0077] The mass ratio of the erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate is 25:15:1;

[0078] According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, first put the base asphalt and the composite emulsifying solubilizer into the mixing kettle and heat it to 150°C. After the base asphalt is melted, start stirring and control the stirring rate at 800 rpm. After stirring and mixing for 30 minutes, add the modified waste tire rubber powder, modified sepiolite and modified diatomaceous earth, and continue stirring and mixing. After the temperature stabilizes at 150°C again, start the high-speed shear dispersing paddle and control the shear rate at 5000 rpm. After shear dispersion treatment for 90 minutes, stop stirring and shear dispersion, and then cool to 75°C before discharging. After discharging, continue to air-cool to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

[0079] Example 3: Preparation method of high-elasticity and noise-reducing soluble rubber powder modified asphalt

[0080] Step 1: Preparation of modified waste tire rubber powder

[0081] After grinding the waste tire rubber powder into a 100-mesh powder, the powder was added to a high-pressure reactor. Then, polydimethyldiallylammonium chloride, N-aminoethylpiperazine, and anhydrous ethanol were added to the reactor. The stirring was started and the stirring rate was controlled at 850 rpm. The temperature was raised to 140° C. and nitrogen was introduced to increase the pressure to 0.8 MPa. The above pressure, temperature, and stirring rate were maintained. After the reaction was carried out for 6 hours, the pressure was released and the temperature was lowered to room temperature. The material was discharged and filtered. The filtered solid was dried at 60° C. for 10 hours to obtain the modified waste tire rubber powder.

[0082] The mass ratio of the waste tire rubber powder, polydimethyldiallyl ammonium chloride, N-aminoethylpiperazine and anhydrous ethanol is 40:6:10:120.

[0083] Step 2: Preparation of modified sepiolite

[0084] Sepiolite, isopropyl distearate acyloxyaluminate, tetramethyl silicate, and p-xylene were mixed in a mass ratio of 50:3.5:6:145, and the mixture was refluxed at 150°C and a stirring rate of 650 rpm for 7 hours. The mixture was then filtered, and the filtered solid was washed four times with anhydrous ethanol and dried at 90°C for 4 hours to obtain a modified sepiolite.

[0085] The particle size of the sepiolite is 3 μm.

[0086] Step 3: Preparation of modified diatomaceous earth

[0087] Diatomaceous earth, bis-[γ-(triethoxysilyl)propyl] tetrasulfide, oleic acid diethanolamide, and toluene were mixed in a mass ratio of 40:6:5:125, and the mixture was refluxed at 110° C. and a stirring rate of 650 rpm for 8 hours. The mixture was then filtered, and the filtered solid was dried at 120° C. for 5 hours to obtain modified diatomaceous earth.

[0088] The particle size of the diatomaceous earth is 9 μm.

[0089] Step 4: Preparation of soluble rubber powder modified asphalt

[0090] The specific formula of the high-elasticity and noise-reducing soluble rubber powder modified asphalt is as follows, in parts by weight:

[0091] 35 parts of modified waste tire rubber powder,

[0092] 95 parts of base asphalt,

[0093] 12 parts of modified sepiolite,

[0094] 15 parts of modified diatomaceous earth,

[0095] 5 parts of composite emulsifying solubilizer;

[0096] The matrix asphalt is No. 70 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction";

[0097] The composite emulsifying solubilizer is composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate;

[0098] The mass ratio of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate is 35:40:4;

[0099] According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, first put the base asphalt and the composite emulsifying solubilizer into the mixing kettle and heat it to 180°C. After the base asphalt is melted, start stirring and control the stirring rate at 1200 rpm. After stirring and mixing for 50 minutes, add the modified waste tire rubber powder, modified sepiolite and modified diatomaceous earth, and continue stirring and mixing. After the temperature stabilizes at 180°C again, start the high-speed shear dispersing paddle and control the shear rate at 9000 rpm. After shear dispersion treatment for 140 minutes, stop stirring and shear dispersion, and then cool to 90°C before discharging. After discharging, continue to air-cool to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

[0100] Comparative Example 1: Based on Example 1, step 1, preparation of modified scrap tire rubber powder, was omitted. In step 4, preparation of soluble rubber powder-modified asphalt, 30 parts of modified scrap tire rubber powder were replaced with 30 parts of scrap tire rubber powder. The specific operation was as follows:

[0101] Step 1, preparation of modified waste tire rubber powder, is not performed;

[0102] The operations of steps 2 and 3 are the same as those in Example 1;

[0103] Step 4: Preparation of soluble rubber powder modified asphalt

[0104] The specific formula of the high-elasticity and noise-reducing soluble rubber powder modified asphalt is as follows, in parts by weight:

[0105] 30 parts of waste tire rubber powder,

[0106] 85 parts of base asphalt,

[0107] 11 parts of modified sepiolite,

[0108] 10 parts of modified diatomaceous earth,

[0109] 3 parts of composite emulsifying solubilizer;

[0110] The particle size of the waste tire rubber powder is 80 mesh;

[0111] The matrix asphalt is No. 70 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction";

[0112] The composite emulsifying solubilizer is composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate;

[0113] The mass ratio of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate is 28:35:3;

[0114] According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, first put the base asphalt and the composite emulsifying solubilizer into the mixing kettle and heat it to 170°C. After the base asphalt is melted, start stirring and control the stirring rate at 1100 rpm. After stirring and mixing for 45 minutes, add the waste tire rubber powder, modified sepiolite and modified diatomaceous earth, and continue stirring and mixing. After the temperature stabilizes at 165°C again, start the high-speed shear dispersion paddle and control the shear rate at 7500 rpm. After shear dispersion treatment for 120 minutes, stop stirring and shear dispersion, and then cool to 80°C before discharging. After discharging, continue to air-cool to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

[0115] Comparative Example 2: Based on Example 1, step 2, preparation of modified sepiolite, was not performed. In step 4, preparation of soluble rubber powder modified asphalt, 11 parts of modified sepiolite were replaced with 11 parts of modified diatomaceous earth. The specific operation was as follows:

[0116] The operation of step 1 is the same as that of Example 1;

[0117] Step 2, preparation of modified sepiolite, is not performed;

[0118] The operation of step 3 is the same as that of embodiment 1;

[0119] Step 4: Preparation of soluble rubber powder modified asphalt

[0120] The specific formula of the high-elasticity and noise-reducing soluble rubber powder modified asphalt is as follows, in parts by weight:

[0121] 30 parts of modified waste tire rubber powder,

[0122] 85 parts of base asphalt,

[0123] 21 parts of modified diatomaceous earth,

[0124] 3 parts of composite emulsifying solubilizer;

[0125] The matrix asphalt is No. 70 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction";

[0126] The composite emulsifying solubilizer is composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate;

[0127] The mass ratio of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate is 28:35:3;

[0128] According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, first put the base asphalt and the composite emulsifying solubilizer into the mixing kettle and heat it to 170°C. After the base asphalt is melted, start stirring and control the stirring rate at 1100 rpm. After stirring and mixing for 45 minutes, add the modified waste tire rubber powder and modified diatomaceous earth, and continue stirring and mixing. After the temperature stabilizes at 165°C again, start the high-speed shear dispersion paddle and control the shear rate at 7500 rpm. After shear dispersion treatment for 120 minutes, stop stirring and shear dispersion, and then cool to 80°C before discharging. After discharging, continue to air-cool to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

[0129] Comparative Example 3: Based on Example 1, step 3, preparation of modified diatomaceous earth, was not performed. In step 4, preparation of soluble rubber powder modified asphalt, 10 parts of modified diatomaceous earth were replaced with 10 parts of modified sepiolite. The specific operation was as follows:

[0130] The operations of steps 1 and 2 are the same as those in Example 1;

[0131] Step 3, preparation of modified diatomaceous earth, is not performed;

[0132] Step 4: Preparation of soluble rubber powder modified asphalt

[0133] The specific formula of the high-elasticity and noise-reducing soluble rubber powder modified asphalt is as follows, in parts by weight:

[0134] 30 parts of modified waste tire rubber powder,

[0135] 85 parts of base asphalt,

[0136] 21 parts of modified sepiolite,

[0137] 3 parts of composite emulsifying solubilizer;

[0138] The matrix asphalt is No. 70 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction";

[0139] The composite emulsifying solubilizer is composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate;

[0140] The mass ratio of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate is 28:35:3;

[0141] According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, first put the base asphalt and the composite emulsifying solubilizer into the mixing kettle and heat it to 170°C. After the base asphalt is melted, start stirring and control the stirring rate at 1100 rpm. After stirring and mixing for 45 minutes, add the modified waste tire rubber powder and modified sepiolite, and continue stirring and mixing. After the temperature stabilizes at 165°C again, start the high-speed shear dispersing paddle and control the shear rate at 7500 rpm. After shear dispersion treatment for 120 minutes, stop stirring and shear dispersion, and then cool to 80°C before discharging. After discharging, continue to air-cool to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

[0142] Comparative Example 4: Based on Example 1, in step 4, in the preparation of the soluble rubber powder modified asphalt, no composite emulsifying solubilizer was added, and 3 parts of the composite emulsifying solubilizer were replaced with 3 parts of the base asphalt in equal amounts. The specific operation was as follows:

[0143] The operations of steps 1, 2, and 3 are the same as those in Example 1;

[0144] Step 4: Preparation of soluble rubber powder modified asphalt

[0145] The specific formula of the high-elasticity and noise-reducing soluble rubber powder modified asphalt is as follows, in parts by weight:

[0146] 30 parts of modified waste tire rubber powder,

[0147] 88 parts of base asphalt,

[0148] 11 parts of modified sepiolite,

[0149] 10 parts of modified diatomaceous earth;

[0150] The matrix asphalt is No. 70 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction";

[0151] According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, the base asphalt is first placed in a mixing kettle and heated to 170°C. After the base asphalt is melted, stirring is started and the stirring rate is controlled at 1100 rpm. After stirring and mixing for 45 minutes, modified scrap tire rubber powder, modified sepiolite and modified diatomaceous earth are added and stirring and mixing is continued. After the temperature stabilizes at 165°C again, the high-speed shear dispersion paddle is turned on and the shear rate is controlled at 7500 rpm. After shear dispersion treatment for 120 minutes, stirring and shear dispersion are stopped, and then the material is cooled to 80°C and discharged. After discharging, the material is continued to be air-cooled to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

[0152] Performance testing:

[0153] The high-elasticity, noise-reducing, solubility-modified rubber powder obtained in Examples 1, 2, 3 and Comparative Examples 1, 2, 3, and 4 was tested for needle penetration at 25°C, softening point, elongation at 5°C, viscosity at 180°C, storage stability, and elastic recovery rate according to the test methods in JTGE20-2011 "Testing Procedures for Asphalt and Asphalt Mixtures for Highway Engineering";

[0154] The noise reduction performance of the highly resilient, noise-reducing, soluble rubber powder-modified asphalt was tested using a tire drop test. The highly resilient, noise-reducing, soluble rubber powder-modified asphalt obtained in Examples 1, 2, and 3 and Comparative Examples 1, 2, 3, and 4 was made into pavement slab specimens in accordance with the requirements of JTGE20-2011, "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering." The tire was allowed to roll freely down the top of a track with a certain slope, plunging onto the pavement slab specimen. The tire / road noise generated at the moment of contact between the tire and the pavement slab specimen was measured. During the tire's roll down the track, a portion of the tire's gravitational potential energy is converted into kinetic energy, resulting in a certain horizontal, vertical, and rotational velocity at the moment the tire contacts the road surface. This process effectively simulates the actual interaction between the tire and the road surface that generates noise.

[0155] The specific results of the above tests are shown in Table 1;

[0156] Table 1

[0157]

[0158] From the data in Table 1, it can be seen that the waste tire rubber powder added in Comparative Example 1 without surface modification has increased needle penetration, decreased softening point, decreased ductility, and very poor storage stability. The elastic recovery rate is more than 20% lower than that of the three embodiments, and the noise level is increased to the highest. This shows that the waste tire rubber powder without surface modification has poor solubility in asphalt and poor dispersibility, which leads to a comprehensive decline in the above indicators. In Comparative Example 2, no modified sepiolite is added, and the needle penetration is significantly increased, the softening point is reduced by about 10°C, the ductility is significantly reduced, the viscosity and storage stability are basically unchanged, and the elastic recovery rate is also significantly reduced. The noise increased significantly, which shows that the modified sepiolite plays a relatively important role in improving the hardness, strength, elasticity and noise reduction performance of asphalt; in Comparative Example 3, no modified diatomaceous earth was added, and the situation was similar to that of Comparative Example 2, except that the softening point, needle penetration, elastic recovery rate and ductility were worse than those of Comparative Example 2. It can be seen that the modified diatomaceous earth has a greater effect on improving the hardness, strength and elasticity of asphalt than the modified sepiolite; the various properties of Comparative Example 4 are the lowest among all the embodiments and comparative examples, which shows that the composite emulsifying solubilizer plays a vital role in promoting the dissolution or dispersion of modified scrap tire rubber powder, modified sepiolite and modified diatomaceous earth in the matrix asphalt.

[0159] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A high-elasticity, noise-reducing, soluble rubber powder modified asphalt, characterized by: The specific formula of the high-elasticity and noise-reducing soluble rubber powder modified asphalt is as follows, in parts by weight: 25~35 parts of modified waste tire rubber powder, 65~95 parts of base asphalt, 5~12 parts of modified sepiolite, 6~15 parts of modified diatomaceous earth, 2~5 parts of composite emulsifying solubilizer; The matrix asphalt is No. 70 asphalt or No. 90 asphalt specified in JTGF40-2019 "Technical Specifications for Highway Asphalt Pavement Construction"; The composite emulsifying solubilizer is composed of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate; The mass ratio of erucamidopropyl dimethyl tertiary amine, stearamidopropyl dimethyl amine, and disodium lauroamphodiacetate is 25-35:15-40:1-4; The modified scrap tire rubber powder is prepared by grinding the scrap tire rubber powder into a powder with a mesh size of 40-100, adding the powder into a high-pressure reactor, then adding polydimethyldiallylammonium chloride, N-aminoethylpiperazine, and anhydrous ethanol into the reactor, starting stirring, controlling the stirring rate at 500-850 rpm, heating to 100-140° C., introducing nitrogen and pressurizing to 0.3-0.8 MPa, maintaining the above pressure, temperature, and stirring rate, reacting for 3-6 hours, releasing the pressure, cooling to room temperature, discharging the material, filtering, and drying the filtered solid at 40-60° C. for 6-10 hours to obtain the modified scrap tire rubber powder. The mass ratio of the waste tire rubber powder, polydimethyldiallylammonium chloride, N-aminoethylpiperazine, and anhydrous ethanol is 25-40:2-6:5-10:80-120; The modified sepiolite is prepared by mixing sepiolite, isopropyl distearate acyloxyaluminate, tetramethyl silicate, and p-xylene in a mass ratio of 25-50:2-3.5:3-6:120-145, controlling the temperature at 135-150° C. and stirring at a rate of 400-650 rpm, performing a reflux reaction for 4-7 hours, filtering, washing the filtered solid with anhydrous ethanol 2-4 times, and drying at 60-90° C. for 1-4 hours to obtain the modified sepiolite. The modified diatomaceous earth is prepared by mixing diatomaceous earth, bis-[γ-(triethoxysilyl)propyl] tetrasulfide, oleic acid diethanolamide, and toluene in a mass ratio of 15-40:2-6:1-5:75-125, controlling the temperature at 85-110° C. and stirring at a rate of 330-650 rpm, performing reflux reaction for 3-8 hours, filtering, and drying the filtered solid at 90-120° C. for 2-5 hours to obtain the modified diatomaceous earth.

2. The high-elasticity and noise-reducing soluble rubber powder modified asphalt according to claim 1, characterized in that: The particle size of the sepiolite is 0.1-3 μm; The particle size of the diatomaceous earth is 0.1-9 μm.

3. The method for preparing the high-elasticity and noise-reducing soluble rubber powder modified asphalt according to claim 1, characterized in that: According to the specific formula of high-elasticity and noise-reducing soluble rubber powder modified asphalt in parts by weight, first put the base asphalt and the composite emulsifying solubilizer into the mixing kettle and heat it to 150~180℃. After the base asphalt is melted, start stirring and control the stirring rate at 800~1200 rpm. After stirring and mixing for 30~50 minutes, add the modified waste tire rubber powder, modified sepiolite and modified diatomaceous earth, and continue stirring and mixing. After the temperature stabilizes at 150~180℃ again, start the high-speed shear dispersing paddle and control the shear rate at 5000~9000 rpm. After shear dispersion treatment for 90~140 minutes, stop stirring and shear dispersion, and then cool to 75~90℃ before discharging. After discharging, continue to air-cool to room temperature to obtain high-elasticity and noise-reducing soluble rubber powder modified asphalt.

Images