Preparation method of rock asphalt modified asphalt

Abstract

The invention relates to the technical field of novel polymer materials, and discloses a preparation method of rock asphalt modified asphalt. The preparation method comprises the following steps: S1, taking 2, 4-dihydroxybenzophenone, adding the 2, 4-dihydroxybenzophenone into ethyl acetate, stirring and dissolving, adjusting the pH value to 3-4, adding 10-undecenal and lauric aldehyde, heating to 70-75 DEG C, stirring for 10-15 hours, and removing a solvent to obtain a modifier; s2, uniformly mixing polyethylene, a modifier and an initiator, carrying out a stirring reaction at 90-100 DEG C for 2-3 h, adding the obtained mixture into a double-screw extruder, and carrying out extrusion and granulation at 150-210 DEG C to obtain modified polyethylene; s3, taking rock asphalt, modified polyethylene and modified rubber powder, blending by a twin-screw extruder, extruding at 150-210 DEG C, granulating, crushing and shearing to obtain modified rock asphalt; and S4, mixing the modified rock asphalt and matrix asphalt, adding a stabilizer, and stirring at a high speed at 140-150 DEG C for 1-2 hours to obtain the rock asphalt modified asphalt.

Description

Technical Field

[0001] The present invention relates to the technical field of new polymer materials, and discloses a preparation method of rock asphalt modified asphalt. Background Technique

[0002] Rock asphalt is an asphalt-like substance formed after the comprehensive action of petroleum for hundreds of millions of years. It has a high degree of polymerization, a large molecular weight, a high softening point, and based on the principle of similar solubility, it has very good compatibility with petroleum asphalt. The asphalt modified with rock asphalt has the advantages of rutting resistance, stripping resistance, aging resistance, and high temperature resistance.

[0003] In order to further improve the low-temperature performance of asphalt, the prior art often blends a polymer with good low-temperature performance with rock asphalt to jointly modify asphalt; the polymer can effectively improve the low-temperature ductility of asphalt, but the simple blending process cannot solve the problems of poor weather resistance and poor compatibility with petroleum asphalt of the polymer. After long-term use, the performance of asphalt will decline, seriously affecting the service life; in summary, it is of great significance to study a preparation method of rock asphalt modified asphalt with good high and low temperature resistance, rutting resistance, long service life, and good compatibility between the modified substance and the matrix asphalt. Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation method of rock asphalt modified asphalt to solve the problems put forward in the above background technique.

[0005] To solve the above technical problems, the present invention provides the following technical solution: A preparation method of rock asphalt modified asphalt, comprising the following steps: S1: Take 2,4-dihydroxybenzophenone, add it to ethyl acetate and stir to dissolve, adjust the pH to 3-4, add 10-undecenal and dodecanal, heat up to 70-75 °C and stir for 10-15 h, remove the solvent to obtain a modifier;

[0006] S2: Mix polyethylene, modifier, and initiator (diisopropylbenzene peroxide) evenly, stir and react at 90-100 °C for 2-3 h, add it to a twin-screw extruder, extrude at 150-210 °C (control the temperature of the first zone of the extruder at 180 °C, the temperature of the second zone at 190 °C, the temperature of the third zone at 200 °C, the temperature of the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm), and pelletize to obtain modified polyethylene;

[0007] S3: Take rock asphalt, modified polyethylene, and modified rubber powder, blend them through a twin-screw extruder, extrude at 150-210 °C (control the temperature of the first zone of the extruder at 180 °C, the temperature of the second zone at 190 °C, the temperature of the third zone at 200 °C, the temperature of the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm), pelletize, crush and shear to obtain modified rock asphalt;

[0008] S4: Mix the modified rock asphalt and the base asphalt at 150 - 180°C for 10 - 15 minutes, add the stabilizer, and stir at high speed at 140 - 150°C for 1 - 2 h to obtain the rock asphalt modified asphalt.

[0009] More preferably, the modifier comprises the following raw materials by mass parts: 20 - 25 parts of 2,4 - dihydroxybenzophenone, 100 - 150 parts of ethyl acetate, 16 - 18 parts of 10 - undecenal, 16 - 20 parts of dodecanal; the modified polyethylene comprises the following raw materials by mass parts: 60 - 80 parts of polyethylene, 10 - 15 parts of modifier, 2 - 3 parts of initiator.

[0010] More preferably, in the modified rock asphalt, the mass ratio of rock asphalt, modified polyethylene, and modified rubber powder is 2:(1 - 1.1):(0.5 - 0.8).

[0011] More preferably, the ash content < 15%, the particle size is 300 - 400 mesh, preferably 400 mesh.

[0012] More preferably, the rock asphalt modified asphalt comprises the following raw materials by mass parts: 40 - 50 parts of modified rock asphalt, 90 - 100 parts of base asphalt, 3 - 5 parts of stabilizer.

[0013] More preferably, the base asphalt is petroleum asphalt, preferably 70# base asphalt and 90# base asphalt.

[0014] More preferably, the base asphalt is 70# base asphalt.

[0015] More preferably, the preparation of the modified rubber powder comprises the following steps: Step 1: Take the waste tire rubber powder with a particle size of 100 - 200 mesh, after washing, add it to the mixed solution of ethanol and water, add methylthiotrimethoxysilane, heat up to 60 - 70°C, stir and mix for 4 - 6 h, filter, wash and dry the solid to obtain the mercapto - modified rubber powder;

[0016] Step 2: Take the mercapto - modified rubber powder, castor oil, and photoinitiator 1173, stir well at room temperature, and react under ultraviolet light with a strength of 20 mW / cm 2 for 20 - 30 min, filter to obtain the solid, wash and dry it to obtain the modified rubber powder.

[0017] More preferably, the mercapto - modified rubber powder comprises the following raw materials by mass parts: 10 - 15 parts of waste tire rubber powder with a particle size of 200 mesh, 80 - 100 parts of ethanol, 30 - 50 parts of water, 1 - 2 parts of methylthiotrimethoxysilane;

[0018] The modified rubber powder comprises the following raw materials by mass parts: 10 - 15 parts of mercapto - modified rubber powder, 5 - 8 parts of castor oil, 0.01 - 0.02 parts of photoinitiator.

[0019] More preferably, the stabilizer comprises an initiator (dicumyl peroxide) and triallyl isocyanurate in a mass ratio of 1:(2-3).

[0020] More preferably, the modified rock asphalt has a particle size of 100-200 mesh, preferably 100 mesh.

[0021] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: A modified rock asphalt is prepared, which comprises rock asphalt, modified polyethylene, and modified rubber powder in a certain mass ratio, and is obtained by co-extrusion using a twin-screw extruder; Rock asphalt has good compatibility with matrix asphalt, can improve its strength and anti-aging performance, but the improvement of low-temperature performance is not obvious; The addition of polyethylene and rubber powder can improve the low-temperature resistance and flexibility of asphalt, but the anti-aging performance is poor and the compatibility with matrix asphalt is not good; Therefore, the present invention obtains the modified rock asphalt by co-extruding the three components, combining the advantages of the three, having good anti-aging performance, good high and low temperature resistance, high strength, and good compatibility with matrix asphalt;

[0022] The modified polyethylene prepared in the present invention comprises 2,4-dihydroxybenzophenone, 10-undecenal, and dodecanal in a certain molar ratio; 2,4-dihydroxybenzophenone itself has good weather resistance, which helps to improve the overall ultraviolet aging resistance. Using its hydroxyl group to graft dodecanal to obtain an alkylbenzene derivative, the benzene ring adsorbs with asphalt through π-π conjugation, and the dodecyl chain forms steric hindrance to improve the overall dispersibility; The length of the alkyl chain needs to be controlled. If it is too short, the improvement of dispersibility is not obvious; if it is too long, it will affect the adsorption between the benzene ring and asphalt, also resulting in an insignificant improvement in dispersibility; 10-undecenal is grafted onto 2,4-dihydroxybenzophenone in the same way, and the introduced double bond can be used for modifying polyethylene, and due to the longer chain segment, the influence of steric hindrance on the grafting rate is reduced;

[0023] The modified rubber powder is first modified with methylthiotrimethoxysilane and then grafted with castor oil to improve flexibility, improve high and low temperature resistance, and introduce a large number of active groups to increase the compatibility with matrix asphalt;

[0024] The present invention also introduces a stabilizer, including dicumyl peroxide and triallyl isocyanurate, to initiate further crosslinking and improve the comprehensive performance. Detailed implementation mode

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0026] It should be noted that there are no special restrictions on the purchasing manufacturers of all raw materials involved in the present invention. Exemplarily, they include: 2,4-dihydroxybenzophenone (CAS: 131-56-6); ethyl acetate (CAS: 141-78-6); 10-undecenal (CAS: 112-45-8); dodecanal (CAS: 112-54-9); polyethylene (Y45330 Yuanye, melt flow rate: 2.01 g / 10 min); dicumyl peroxide (CAS: 80-43-3); ethanol (CAS: 64-17-5); methylthiotrimethoxysilane (CAS: 30817-94-8); castor oil (S24344, Yuanye); photoinitiator 1173 (CAS: 7473-98-5); triallyl isocyanurate (CAS: 1025-15-6); 4-(3-butenyl)benzaldehyde (CAS: 137658-83-4);

[0027] Unless otherwise specified, the following are all in parts by mass or mass ratio;

[0028] The stabilizer is dicumyl peroxide and triallyl isocyanurate with a mass ratio of 1:1;

[0029] Example 1: S1: Take 22 parts of 2,4-dihydroxybenzophenone, add it to 120 parts of ethyl acetate and stir to dissolve. Adjust the pH to 3, add 17 parts of 10-undecenal and 18 parts of dodecanal, heat up to 75 °C and stir for 12 h, remove the solvent to obtain a modifier;

[0030] S2: Add 70 parts of polyethylene to a mixer, add 12 parts of the modifier and 3 parts of dicumyl peroxide, mix evenly, stir and react at 95 °C for 2 h, add it to a twin-screw extruder for extrusion and granulation. Control the temperature of the first zone of the extruder to be 180 °C, the second zone to be 190 °C, the third zone to be 200 °C, the fourth zone to be 210 °C, and the screw speed of the extruder to be 15 rpm to obtain modified polyethylene;

[0031] S3: Take 12 parts of waste tire rubber powder, after washing, add it to a mixed solution of 100 parts of ethanol and 30 parts of water, add 2 parts of methylthiotrimethoxysilane, heat up to 60 °C, stir and mix for 5 h, filter, wash and dry the solid to obtain mercapto-functionalized rubber powder;

[0032] S4: Take 14 parts of mercapto-functionalized rubber powder, 7 parts of castor oil, and 0.01 part of photoinitiator 1173, stir well at room temperature, and react under ultraviolet light irradiation with a strength of 20 mW / cm 2 for 20 min, filter to obtain the solid, wash and dry to obtain modified rubber powder;

[0033] S5: Take rock asphalt, modified polyethylene, and modified rubber powder with a mass ratio of 2:1:0.6, blend them in a twin-screw extruder, extrude, pelletize, and crush and shear. Control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm to obtain modified rock asphalt;

[0034] S6: Mix 45 parts of modified rock asphalt and 95 parts of matrix asphalt at 180 °C for 10 minutes, add 4 parts of stabilizer, and stir at high speed at 150 °C for 1 h to obtain rock asphalt modified asphalt.

[0035] Example 2: S1: Take 20 parts of 2,4-dihydroxybenzophenone, add it to 120 parts of ethyl acetate and stir to dissolve, adjust the pH to 3, add 16 parts of 10-undecenal and 16 parts of dodecanal, heat up to 75 °C and stir for 12 h, remove the solvent to obtain a modifier;

[0036] S2: Add 65 parts of polyethylene to a mixer, add 10 parts of modifier and 3 parts of initiator dicumyl peroxide, mix evenly, stir and react at 95 °C for 2 h, add it to a twin-screw extruder for extrusion and pelletization. Control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm to obtain modified polyethylene;

[0037] S3: Take 10 parts of waste tire rubber powder, after washing, add it to a mixed solution of 100 parts of ethanol and 30 parts of water, add 1 part of methylthiotrimethoxysilane, heat up to 60 °C, stir and mix for 5 h, filter, wash and dry the solid to obtain mercapto-functionalized rubber powder;

[0038] S4: Take 10 parts of mercapto-functionalized rubber powder, 5 parts of castor oil, and 0.01 part of photoinitiator 1173, stir well at room temperature, and react under ultraviolet light irradiation with a strength of 20 mW / cm 2 for 20 min, filter to obtain the solid, wash and dry to obtain modified rubber powder;

[0039] S5: Take rock asphalt, modified polyethylene, and modified rubber powder with a mass ratio of 2:1:0.5, blend them in a twin-screw extruder, extrude, pelletize, and crush and shear. Control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm to obtain modified rock asphalt;

[0040] S6: Mix 40 parts of modified rock asphalt and 90 parts of matrix asphalt at 180 °C for 10 minutes, add 3 parts of stabilizer, and stir at high speed at 150 °C for 1 h to obtain rock asphalt modified asphalt.

[0041] Example 3: S1: Take 25 parts of 2,4-dihydroxybenzophenone, add it to 120 parts of ethyl acetate and stir to dissolve. Adjust the pH to 3, add 18 parts of 10-undecenal and 20 parts of dodecanal, heat up to 75 °C and stir for 12 h, remove the solvent to obtain a modifier;

[0042] S2: Add 80 parts of polyethylene into a mixer, add 15 parts of the modifier and 3 parts of initiator diisopropylbenzene peroxide, mix evenly, stir and react at 95 °C for 2 h, add it to a twin-screw extruder for extrusion and pelletization. Control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm to obtain modified polyethylene;

[0043] S3: Take 15 parts of waste tire rubber powder, after washing, add it to a mixed solution of 100 parts of ethanol and 30 parts of water, add 2 parts of methylthiotrimethoxysilane, heat up to 60 °C, stir and mix for 5 h, filter, wash and dry the solid to obtain mercapto-functionalized rubber powder;

[0044] S4: Take 15 parts of mercapto-functionalized rubber powder, 8 parts of castor oil, and 0.01 part of photoinitiator 1173, stir well at room temperature, and react under ultraviolet light irradiation with a strength of 20 mW / cm 2 for 20 min, filter to obtain the solid, wash and dry to obtain modified rubber powder;

[0045] S5: Take rock asphalt, modified polyethylene, and modified rubber powder with a mass ratio of 2:1.1:0.5, blend them through a twin-screw extruder, extrude, pelletize, crush and shear. Control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm to obtain modified rock asphalt;

[0046] S6: Mix 50 parts of modified rock asphalt and 100 parts of base asphalt at 180 °C for 10 minutes, add 5 parts of stabilizer, and stir at high speed at 150 °C for 1 h to obtain rock asphalt modified asphalt.

[0047] Comparative Example 1 (changing the preparation method of the modifier, and the other method steps are the same as those in Example 1): S1: Take 22 parts of 2,4-dihydroxybenzophenone, add it to 120 parts of ethyl acetate and stir to dissolve. Adjust the pH to 3, add 17 parts of 4-(3-butenyl)benzaldehyde, heat up to 75 °C and stir for 12 h, remove the solvent to obtain a modifier;

[0048] S2: Add 70 parts of polyethylene into a mixer, add 12 parts of modifier and 3 parts of initiator diisopropylbenzene peroxide, mix evenly, stir and react at 95°C for 2 h, add into a twin-screw extruder for extrusion and pelletization, control the temperature of the first zone of the extruder at 180°C, the second zone at 190°C, the third zone at 200°C, the fourth zone at 210°C, and the screw speed of the extruder at 15 rpm to obtain modified polyethylene;

[0049] S3: Take 12 parts of waste tire rubber powder, after washing, add it into a mixed solution of 100 parts of ethanol and 30 parts of water, add 2 parts of methylthiotrimethoxysilane, heat up to 60°C, stir and mix for 5 h, filter, wash and dry the solid to obtain mercapto-functionalized rubber powder;

[0050] S4: Take 14 parts of mercapto-functionalized rubber powder, 7 parts of castor oil, and 0.01 part of photoinitiator 1173, stir well at room temperature, and react under ultraviolet light irradiation with an intensity of 20 mW / cm 2 for 20 min, filter to obtain the solid, wash and dry to obtain modified rubber powder;

[0051] S5: Take rock asphalt, modified polyethylene, and modified rubber powder with a mass ratio of 2:1:0.6, blend them through a twin-screw extruder, extrude, pelletize, crush and shear, control the temperature of the first zone of the extruder at 180°C, the second zone at 190°C, the third zone at 200°C, the fourth zone at 210°C, and the screw speed of the extruder at 15 rpm to obtain modified rock asphalt;

[0052] S6: Mix 45 parts of modified rock asphalt and 95 parts of base asphalt at 180°C for 10 minutes, add 4 parts of stabilizer, and stir at high speed at 150°C for 1 h to obtain rock asphalt modified asphalt.

[0053] Comparative Example 2 (changing the raw material ratio of modified rock asphalt, and the other method steps are the same as those in Example 1): S1: Take 22 parts of 2,4-dihydroxybenzophenone, add it into 120 parts of ethyl acetate and stir to dissolve, adjust the pH to 3, add 17 parts of 10-undecenal and 18 parts of dodecanal, heat up to 75°C and stir for 12 h, remove the solvent to obtain the modifier;

[0054] S2: Add 70 parts of polyethylene into a mixer, add 12 parts of modifier and 3 parts of initiator diisopropylbenzene peroxide, mix evenly, stir and react at 95°C for 2 h, add into a twin-screw extruder for extrusion and pelletization, control the temperature of the first zone of the extruder at 180°C, the second zone at 190°C, the third zone at 200°C, the fourth zone at 210°C, and the screw speed of the extruder at 15 rpm to obtain modified polyethylene;

[0055] S3: Take 12 parts of waste tire rubber powder. After washing, add it to a mixed solution of 100 parts of ethanol and 30 parts of water. Add 2 parts of methylthiotrimethoxysilane, heat up to 60 °C, stir and mix for 5 h, filter, wash and dry the solid to obtain mercapto-functionalized rubber powder;

[0056] S4: Take 14 parts of mercapto-functionalized rubber powder, 7 parts of castor oil, and 0.01 part of photoinitiator 1173. Stir well at room temperature and react under ultraviolet light irradiation with an intensity of 20 mW / cm 2 for 20 min. Filter to obtain the solid, wash and dry it to obtain modified rubber powder;

[0057] S5: Take rock asphalt, modified polyethylene, and modified rubber powder with a mass ratio of 2:0.5:0.3. Blend them in a twin-screw extruder, extrude, pelletize, and crush and shear. Control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, and the fourth zone at 210 °C. The screw speed of the extruder is 15 rpm to obtain modified rock asphalt;

[0058] S6: Mix 45 parts of modified rock asphalt and 95 parts of matrix asphalt at 180 °C for 10 minutes. Add 4 parts of stabilizer and stir at high speed at 150 °C for 1 h to obtain rock asphalt modified asphalt.

[0059] Comparative Example 3 (using a modified mixture instead of modified rock asphalt, and the remaining method steps are the same as those in Example 1): S1: Take 22 parts of 2,4-dihydroxybenzophenone, add it to 120 parts of ethyl acetate and stir to dissolve. Adjust the pH to 3, add 17 parts of 10-undecenal and 18 parts of dodecanal, heat up to 75 °C and stir for 12 h, remove the solvent to obtain a modifier;

[0060] S2: Add 70 parts of polyethylene to a mixer, add 12 parts of the modifier and 3 parts of initiator dicumyl peroxide, mix evenly, stir and react at 95 °C for 2 h, add it to a twin-screw extruder for extrusion and pelletization. Control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, and the fourth zone at 210 °C. The screw speed of the extruder is 15 rpm to obtain modified polyethylene;

[0061] S3: Take 12 parts of waste tire rubber powder. After washing, add it to a mixed solution of 100 parts of ethanol and 30 parts of water. Add 2 parts of methylthiotrimethoxysilane, heat up to 60 °C, stir and mix for 5 h, filter, wash and dry the solid to obtain mercapto-functionalized rubber powder;

[0062] S4: Take 14 parts of mercapto-functionalized rubber powder, 7 parts of castor oil, and 0.01 part of photoinitiator 1173. Stir well at room temperature and react under ultraviolet light irradiation with an intensity of 20 mW / cm 2 for 20 min. Filter to obtain the solid, wash and dry it to obtain modified rubber powder;

[0063] S5: Take rock asphalt, modified polyethylene, and modified rubber powder with a mass ratio of 2:1:0.6, mix them to obtain a modified mixture.

[0064] S6: Mix 45 parts of the modified mixture and 95 parts of matrix asphalt at 180 °C for 10 minutes, add 4 parts of stabilizer, and stir at high speed at 150 °C for 1 h to obtain rock asphalt modified asphalt.

[0065] Comparative Example 4 (changing the raw material ratio of modified rock asphalt, and the remaining method steps are the same as those in Example 1): S1: Take 22 parts of 2,4-dihydroxybenzophenone, add it to 120 parts of ethyl acetate and stir to dissolve, adjust the pH to 3, add 17 parts of 10-undecenal and 18 parts of dodecanal, heat up to 75 °C and stir for 12 h, remove the solvent to obtain a modifier.

[0066] S2: Add 70 parts of polyethylene to a mixer, add 12 parts of the modifier and 3 parts of initiator dicumyl peroxide, mix evenly, stir and react at 95 °C for 2 h, add it to a twin-screw extruder for extrusion and granulation, control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm to obtain modified polyethylene.

[0067] S3: Take 12 parts of waste tire rubber powder, after washing, add it to a mixed solution of 100 parts of ethanol and 30 parts of water, add 2 parts of methylthiotrimethoxysilane, heat up to 60 °C, stir and mix for 5 h, filter, wash and dry the solid to obtain mercapto-functionalized rubber powder.

[0068] S4: Take 14 parts of mercapto-functionalized rubber powder, 7 parts of castor oil, and 0.01 part of photoinitiator 1173, stir well at room temperature, react under ultraviolet light irradiation with an intensity of 20 mW / cm2 for 20 min, filter to obtain the solid, wash and dry it to obtain modified rubber powder.

[0069] S5: Take rock asphalt, modified polyethylene, and modified rubber powder with a mass ratio of 1:1:0.6, blend them through a twin-screw extruder, extrude, granulate, crush and shear, control the temperature of the first zone of the extruder at 180 °C, the second zone at 190 °C, the third zone at 200 °C, the fourth zone at 210 °C, and the screw speed of the extruder at 15 rpm to obtain modified rock asphalt.

[0070] S6: Mix 45 parts of the modified rock asphalt and 95 parts of matrix asphalt at 180 °C for 10 minutes, add 4 parts of stabilizer, and stir at high speed at 150 °C for 1 h to obtain rock asphalt modified asphalt.

[0071] Performance test: Take the rock asphalt modified asphalt prepared in Examples 1 to 3 and Comparative Examples 1 to 4; (1) Place it in an ultraviolet aging test chamber for ultraviolet aging experiment, and the ultraviolet intensity is 1200 wu / cm 2, the aging temperature is 60°C, the aging time is 6 days, and the 5°C ductility change rate (decrease rate) is tested; (2) Aggregates, rock asphalt modified asphalt, and mineral powder are mixed in a mass ratio of 100:(6 - 10):(1 - 3) to prepare asphalt concrete for testing; among them, the mineral powder is limestone mineral powder; the aggregates are fine aggregates and coarse aggregates with a mass ratio of 1:2; the fine aggregates are river sand with a particle size of 2.0 - 2.5 mm, and the coarse aggregates are crushed basalt, with 40 wt% having a particle size of 10 - 20 mm, 35 wt% having a particle size of 5 - 10 mm, and 25 wt% having a particle size of 2 - 5 mm; see Table 1 for details.

[0072] Table 1:

[0073]

[0074] Conclusion: In Comparative Example 1, the preparation method of the modifier was changed, dodecyl aldehyde was not added, and 4-(3-butenyl)benzaldehyde was used instead of 10-undecenal. Due to the change in the structure of the modifier, the overall performance decreased; in Comparative Examples 2 and 4, the raw material ratios of the modified rock asphalt were changed, and the performance was inferior to that of the examples. It can be seen that the ratios of rock asphalt, modified polyethylene, and modified rubber powder are of great significance; in Comparative Example 3, the modified mixture was used instead of the modified rock asphalt, that is, rock asphalt, modified polyethylene, and modified rubber powder were directly mixed and added. Due to problems such as compatibility and dispersibility, the performance decreased significantly; in summary, the rock asphalt prepared by the present invention has good dispersibility, and the rock asphalt modified asphalt has good aging resistance, anti-deformation ability, mechanical properties, stability, and high and low temperature resistance.

[0075] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A preparation method of rock asphalt modified asphalt, characterized in that: The following steps are involved: S1: Take 2,4-dihydroxybenzophenone, add it to ethyl acetate and stir to dissolve, adjust the pH to 3-4, add 10-undecenal and dodecanal, raise the temperature to 70-75°C and stir for 10-15h, remove the solvent, and obtain a modifier; S2: Mix polyethylene, modifier and initiator evenly, stir and react at 90-100°C for 2-3h, add to a twin-screw extruder, extrude and granulate at 150-210°C to obtain modified polyethylene; S3: rock asphalt, modified polyethylene and modified rubber powder are mixed in a twin-screw extruder, extruded at 150-210°C, granulated, crushed and sheared to obtain modified rock asphalt; S4: Mix the modified rock asphalt and base asphalt at 150-180°C for 10-15 minutes, add a stabilizer, and stir at a high speed at 140-150°C for 1-2 hours to obtain rock asphalt modified asphalt.

2. The preparation method of a rock asphalt modified asphalt according to claim 1, characterized in that: The modifier comprises the following raw materials, calculated by mass: 20 to 25 parts of 2,4-dihydroxybenzophenone, 100 to 150 parts of ethyl acetate, 16 to 18 parts of 10-undecenal, and 16 to 20 parts of dodecanal; the modified polyethylene comprises the following raw materials, calculated by mass: 60 to 80 parts of polyethylene, 10 to 15 parts of modifier, and 2 to 3 parts of initiator.

3. The preparation method of a rock asphalt modified asphalt according to claim 1, characterized in that: In the modified rock asphalt, the mass ratio of rock asphalt, modified polyethylene and modified rubber powder is 2:(1-1.1):(0.5-0.8).

4. The preparation method of a rock asphalt modified asphalt according to claim 1, characterized in that: The rock asphalt modified asphalt includes the following raw materials, calculated by weight: 40 to 50 parts of modified rock asphalt, 90 to 100 parts of base asphalt, and 3 to 5 parts of stabilizer.

5. The preparation method of a rock asphalt modified asphalt according to claim 1, characterized in that: The preparation of the modified rubber powder comprises the following steps: Step 1: taking waste tire rubber powder, washing it, adding it to a mixed solution of ethanol and water, adding methylmercaptotrimethoxysilane, heating it to 60-70° C., stirring and mixing for 4-6 hours, filtering, washing and drying the solid, and obtaining mercapto-modified rubber powder; Step 2: Take thiolated rubber powder, castor oil, and photoinitiator, stir them fully at room temperature, react them under ultraviolet light for 20 to 30 minutes, and post-treat them to obtain modified rubber powder.

6. The preparation method of a rock asphalt modified asphalt according to claim 5, characterized in that: The mercaptolated rubber powder comprises the following raw materials, calculated by weight: 10 to 15 parts of waste tire rubber powder, 80 to 100 parts of ethanol, 30 to 50 parts of water, and 1 to 2 parts of methylmercaptotrimethoxysilane; The modified rubber powder comprises the following raw materials, calculated by weight: 10 to 15 parts of mercaptolated rubber powder, 5 to 8 parts of castor oil, and 0.01 to 0.02 parts of photoinitiator.

7. The preparation method of rock asphalt modified asphalt according to claim 1, characterized in that: The stabilizer comprises an initiator and triallyl isocyanurate in a mass ratio of 1:(2-3).

8. The preparation method of a rock asphalt modified asphalt according to claim 1, characterized in that: The particle size of the modified rock asphalt is 100-200 meshes.

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