Organic phosphorus zirconium modified asphalt and preparation method thereof

Abstract

The application discloses a kind of organic zirconium phosphate modified asphalt and preparation method thereof, belong to bitumen material preparation technical field.The raw materials of the organic zirconium phosphate modified asphalt include: 100 parts of base asphalt, 5-15 parts of organic zirconium phosphate.The application utilizes ionic organosiloxane, anionic surfactant to carry out secondary grafting on the surface of zirconium phosphate, so that the surface of zirconium phosphate has long chain structure, so as to obtain organic zirconium phosphate.Two graftings of ionic organosiloxane and anionic surfactant promote the transformation of zirconium phosphate from nanoscale solid powder to fluid-like material, which can effectively avoid the agglomeration phenomenon between zirconium phosphate particles, greatly improve the compatibility of zirconium phosphate and asphalt.Adding organic zirconium phosphate modifier tending to fluid-like to asphalt can not only improve the low-temperature performance of asphalt, but also its unique lamellar structure can effectively absorb and block ultraviolet light, greatly improve the anti-ultraviolet aging ability of asphalt.

Description

Technical Field

[0001] This invention relates to the field of asphalt material preparation technology, and in particular to an organozirconium phosphate modified asphalt and its preparation method. Background Technology

[0002] Asphalt pavement is widely used due to its good smoothness, short construction period, and ease of maintenance. However, as an organic material, asphalt is prone to aging under the influence of natural environmental factors such as light, oxygen, and heat. In particular, under high-energy ultraviolet radiation, some chemical bonds in the asphalt material molecules break, causing the asphalt to harden and become brittle. This leads to a gradual decline in the low-temperature crack resistance and fatigue resistance of asphalt mixtures, making the pavement prone to rutting, potholes, and spalling, which seriously affects driving comfort and safety.

[0003] Adding modifiers to asphalt is one of the effective ways to improve its resistance to ultraviolet aging. Previous studies have shown that adding layered inorganic materials to asphalt can effectively improve its UV resistance, such as magnesium-aluminum layered double hydroxides, montmorillonite, and vermiculite. However, the poor compatibility of inorganic particles with asphalt leads to severe agglomeration, which seriously damages the low-temperature performance of asphalt. Organic treatment of inorganic particles is often necessary to mitigate this negative impact. Existing research has shown many cases where organic treatment has improved the compatibility of inorganic particles with asphalt, but the improvement effect is limited and cannot fundamentally solve the problem of poor low-temperature performance of asphalt. Therefore, how to improve the UV resistance of asphalt while ensuring its low-temperature performance is a technical challenge that needs to be overcome by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide an organozirconium phosphate modified bitumen and its preparation method, so as to solve the problems existing in the prior art.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] One of the technical solutions of the present invention is: an organozirconium phosphate modified bitumen, which, by mass parts, comprises: 100 parts of base bitumen and 5-15 parts of organozirconium phosphate;

[0007] The organozirconium phosphate is obtained by sequentially surface-modifying zirconium phosphate with ionic organosiloxanes and anionic surfactants.

[0008] This invention utilizes ionic organosiloxanes and anionic surfactants to perform secondary grafting on the surface of zirconium phosphate, resulting in a long-chain structure on the zirconium phosphate surface, thus obtaining organozirconium phosphate. The secondary grafting of ionic organosiloxanes and anionic surfactants promotes the transformation of zirconium phosphate from a nanoscale solid powder to a fluid-like material. This effectively avoids the aggregation of zirconium phosphate particles and significantly improves the compatibility of zirconium phosphate with asphalt. Adding a fluid-like organozirconium phosphate modifier to asphalt not only improves the low-temperature performance of the asphalt (the secondary surface grafting gives organozirconium phosphate a flexible long-chain structure, significantly improving hydrophobicity and reducing the density difference with asphalt, which is beneficial for improving the compatibility of zirconium phosphate with asphalt and enhancing the storage stability of the modified asphalt; in addition, the flexible long-chain structure can also improve the low-temperature deformation capacity and low-temperature crack resistance of asphalt), but its unique layered structure can also effectively absorb and block ultraviolet rays, significantly improving the asphalt's resistance to ultraviolet aging. This invention effectively improves the resistance to ultraviolet aging of asphalt while ensuring its low-temperature performance.

[0009] Further, the preparation steps of the organozirconium phosphate include: hydroxyl modification of zirconium phosphate to obtain hydroxylated zirconium phosphate; dispersing the hydroxylated zirconium phosphate in water, then adding a methanol solution of an ionic organosiloxane, stirring for 2-4 hours, then adding an aqueous solution of an anionic surfactant, heating and stirring for 10-12 hours to obtain the organozirconium phosphate (i.e., firstly grafting zirconium phosphate with an ionic organosiloxane to obtain primary grafted zirconium phosphate, then secondly grafting zirconium phosphate with an anionic surfactant to obtain secondary grafted zirconium phosphate, which is the organozirconium phosphate; the grafting modification process and grafting structure are shown in the schematic diagram). Figure 1 (As shown).

[0010] Hydroxyl modification of zirconium phosphate can increase the activity of hydroxyl groups on the zirconium phosphate surface, thereby improving the surface modification efficiency. Dispersing hydroxylated zirconium phosphate in water and adding a methanol solution of ionic organosiloxanes with stirring can graft the ionic organosiloxanes onto the zirconium phosphate surface, achieving the organication of zirconium phosphate. Adding an aqueous solution of anionic surfactant and continuing stirring can connect the anionic surfactant to the ionic organosiloxanes on the zirconium phosphate surface, further lengthening the grafted chain structure on the zirconium phosphate surface and significantly improving the compatibility of zirconium phosphate particles with asphalt.

[0011] Furthermore, the ionic organosiloxane is an ammonium salt organosiloxane.

[0012] Ammonium salt organosiloxanes can react with hydroxyl groups on the surface of zirconium phosphate, thereby grafting onto the zirconium phosphate surface and providing cations (NH4+). 4+ It combines with anionic surfactants.

[0013] Furthermore, the ammonium salt organosiloxane is one of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, dodecyl dimethyl(3-trimethoxysilyl)propyl]ammonium chloride, and dimethyl dodecyl[3-(triethoxysilyl)propyl]ammonium chloride, preferably dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride.

[0014] Dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride has a long carbon chain structure, which is most similar to the structure of asphalt constituent molecules, and thus has good compatibility with asphalt.

[0015] Furthermore, the anionic surfactant includes sodium alkyl sulfonate, sodium alkyl aryl sulfonate, sodium alkyl sulfate, sodium secondary alkyl sulfate, or sodium lignosulfonate, preferably sodium lignosulfonate.

[0016] Anionic surfactants can combine with ammonium salt organosiloxanes to further increase the carbon chain length on the surface of zirconium phosphate. Sodium lignosulfonate is the preferred anionic surfactant. Sodium lignosulfonate is rich in phenolic hydroxyl structures, which can capture free radicals and further improve the anti-aging properties of organozirconium phosphate modified asphalt.

[0017] Furthermore, the ratio of the amount of hydroxylated zirconium phosphate, water, methanol solution of ionic organosiloxane, and aqueous solution of anionic surfactant is 1g:8-12g:8-12g:5-10mL.

[0018] Furthermore, the concentration of the methanol solution of the ionic organosiloxane is 30-50 wt%; and the concentration of the aqueous solution of the anionic surfactant is 10-20 wt%.

[0019] Further, the hydroxylation modification of zirconium phosphate to obtain hydroxylated zirconium phosphate includes: mixing zirconium phosphate and water, adjusting the pH of the mixed solution to 9-11, and stirring for 8-10 hours to obtain the hydroxylated zirconium phosphate.

[0020] Furthermore, the mass ratio of zirconium phosphate to water is 1:8 to 12.

[0021] Furthermore, after the stirring is completed, the process also includes the steps of vacuum filtration and washing until the filtrate is neutral, and then drying.

[0022] Furthermore, the heating and stirring temperature is 60–80°C.

[0023] Furthermore, after the heating and stirring are completed, the process also includes steps of filtration, washing, and vacuum drying.

[0024] The second technical solution of the present invention: The preparation method of the above-mentioned organozirconium phosphate modified pitch includes the following steps:

[0025] The base asphalt is preheated to 150-170°C and then organozirconium phosphate is added. The asphalt is then subjected to high-speed shearing at 150-170°C for 30-60 minutes to obtain the organozirconium phosphate modified asphalt.

[0026] Furthermore, the high-speed stirring speed is 4000-5000 rpm.

[0027] The third technical solution of the present invention: a method for improving the resistance of asphalt to ultraviolet aging while ensuring the low-temperature performance of asphalt, using organozirconium phosphate to modify the matrix asphalt;

[0028] The organozirconium phosphate is obtained by sequentially surface-modifying zirconium phosphate with ionic organosiloxanes and anionic surfactants.

[0029] The present invention discloses the following technical effects:

[0030] (1) In this invention, ionic organosiloxanes are grafted onto the surface of zirconium phosphate through surface modification, and then anionic surfactants are used to combine with the ionic organosiloxanes to obtain organozirconium phosphate. The secondary grafting gives the zirconium phosphate surface a long carbon chain structure. Compared with ordinary zirconium phosphate and conventionally surface-modified zirconium phosphate, the organozirconium phosphate prepared by this invention tends to be fluid-like, which can significantly enhance the affinity between zirconium phosphate and asphalt, avoid the aggregation of zirconium phosphate particles in asphalt, and greatly improve the compatibility between zirconium phosphate and asphalt.

[0031] (2) The present invention adds organozirconium phosphate, which tends to be fluid, to the matrix asphalt, which can improve the ductility of the asphalt, enhance the crack resistance of the road under low temperature conditions, and help extend the service life of the road surface.

[0032] (3) This invention utilizes the multi-level chemical absorption and physical shielding effect of organophosphoric zirconium on ultraviolet rays to give asphalt materials excellent ultraviolet blocking effect, significantly improve the aging resistance of road asphalt, and facilitate the long-term service of asphalt pavement. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the grafting modification process and grafting structure of zirconium phosphate obtained by primary grafting modification with ionic organosiloxane and secondary grafting modification with anionic surfactant in this invention. Detailed Implementation

[0035] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0036] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0037] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0038] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0039] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0040] As a first aspect of the present invention, the present invention provides an organozirconium phosphate modified bitumen, wherein the raw materials, by mass parts, include: 100 parts of base bitumen and 5 to 15 parts of organozirconium phosphate.

[0041] The organozirconium phosphate is obtained by sequentially surface-modifying zirconium phosphate with ionic organosiloxanes and anionic surfactants.

[0042] In a preferred embodiment of the present invention, the ionic organosiloxane is an ammonium salt organosiloxane.

[0043] In a preferred embodiment of the present invention, the anionic surfactant includes sodium alkyl sulfonate, sodium alkyl aryl sulfonate, sodium alkyl sulfate, sodium secondary alkyl sulfate, or sodium lignin sulfonate.

[0044] In a preferred embodiment of the present invention, the ammonium salt organosiloxane is one of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, dodecyl dimethyl(3-trimethoxysilyl)propyl)ammonium chloride, and dimethyl dodecyl[3-(triethoxysilyl)propyl]ammonium chloride.

[0045] In a preferred embodiment of the present invention, the ammonium salt organosiloxane is dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride; and the anionic surfactant is sodium lignosulfonate.

[0046] As an embodiment of the present invention, the preparation steps of the organozirconium phosphate include: hydroxyl modification of zirconium phosphate to obtain hydroxylated zirconium phosphate; dispersing the hydroxylated zirconium phosphate in water, then adding a methanol solution of an ionic organosiloxane, stirring for 2-4 hours, then adding an aqueous solution of an anionic surfactant, heating and stirring for 10-12 hours to obtain the organozirconium phosphate (i.e., firstly grafting zirconium phosphate with an ionic organosiloxane to obtain primary grafted zirconium phosphate, then secondly grafting zirconium phosphate with an anionic surfactant to obtain secondary grafted zirconium phosphate, which is the organozirconium phosphate; the grafting modification process and grafting structure are shown in the figure). Figure 1 (As shown).

[0047] As an embodiment of the present invention, the hydroxylation modification of zirconium phosphate to obtain hydroxylated zirconium phosphate includes: mixing zirconium phosphate and water, adjusting the pH of the mixed solution to 9-11, and stirring for 8-10 hours to obtain the hydroxylated zirconium phosphate.

[0048] As a preferred embodiment of the present invention, the more specific preparation steps of the organozirconium phosphate include: placing 10 parts of zirconium phosphate in a beaker, adding 80-120 parts of water, and then adding sodium hydroxide aqueous solution dropwise (the concentration of sodium hydroxide aqueous solution is not required) until the pH of the solution reaches 9-11, stirring at room temperature (1000-2000 rpm) for 8-10 hours, filtering and washing until the filtrate is neutral, and drying to obtain hydroxylated zirconium phosphate; dispersing 10g of hydroxylated zirconium phosphate in 80-120g of water, and then adding 80-120g of a methanol solution of ionic organosiloxane (concentration 30-50wt%), stirring (1000-2000 rpm) for 2-4 hours; subsequently adding 50-100mL of anionic surfactant aqueous solution (concentration 10-20wt%), stirring at 60-80℃ (1000-2000 rpm) for 10-12 hours, filtering, washing, and vacuum drying to constant weight to obtain organozirconium phosphate.

[0049] As a second aspect of the present invention, the present invention provides a method for preparing the above-mentioned organozirconium phosphate modified pitch, comprising the following steps:

[0050] The base asphalt is preheated to 150-170°C and then organozirconium phosphate is added. The asphalt is then sheared at high speed (4000-5000 rpm) for 30-60 minutes at 150-170°C to obtain the organozirconium phosphate modified asphalt.

[0051] As a third aspect of the present invention, the present invention provides a method for improving the resistance of asphalt to ultraviolet aging while ensuring the low-temperature performance of asphalt, by using organozirconium phosphate to modify the base asphalt;

[0052] The organozirconium phosphate is obtained by sequentially surface-modifying zirconium phosphate with ionic organosiloxanes and anionic surfactants.

[0053] The organozirconium phosphate modified pitch and its preparation method of the present invention will be further described below with reference to specific embodiments.

[0054] In the specific embodiments of the present invention, room temperature specifically refers to 20-30℃.

[0055] All raw materials used in the specific embodiments of this invention are commercially available products. Specifically, the CAS numbers for dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride are 27668-52-6, dodecyl dimethyl(3-trimethoxysilyl)propyl)ammonium chloride is 27668-53-7, sodium lignosulfonate is 8061-51-6, sodium dodecyl sulfate is 151-21-3, and sodium 2,5-dimethylbenzenesulfonate is 827-19-0. The base asphalt is specifically road base asphalt, grade 70#.

[0056] Example 1

[0057] An organozirconium phosphate modified bitumen, by mass parts, has the following raw material composition: 10 parts organozirconium phosphate and 100 parts matrix bitumen.

[0058] The preparation method of organozirconium phosphate modified pitch includes the following steps:

[0059] S1. Preparation of organozirconium phosphate: Weigh 10 parts of zirconium phosphate into a beaker, add 100 parts of deionized water, and then add sodium hydroxide aqueous solution dropwise until the pH of the solution reaches 10. Stir at room temperature (1500 rpm) for 10 h, then filter and wash until the filtrate is neutral. Dry to obtain hydroxylated zirconium phosphate. Take 10 g of hydroxylated zirconium phosphate and disperse it in 100 g of deionized water, then add 100 g of methanol solution (40 wt%) of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, and stir (1500 rpm) for 3 h. Then add 75 mL of sodium lignosulfonate aqueous solution (15 wt%), stir at 70 °C (1500 rpm) for 12 h, filter, wash, and vacuum dry to constant weight to obtain organozirconium phosphate.

[0060] S2. Preparation of organozirconium phosphate modified asphalt: After preheating the base asphalt to 160℃, organozirconium phosphate is added in proportion, and the asphalt is sheared at high speed (4000 rpm) for 30 minutes at 160℃ to obtain organozirconium phosphate modified asphalt.

[0061] Example 2

[0062] Same as Example 1, except that the aqueous solution of sodium lignosulfonate is replaced with an aqueous solution of sodium dodecyl sulfate of equal concentration and volume.

[0063] Example 3

[0064] Same as Example 1, except that the concentration of the added dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride methanol solution is 30 wt%.

[0065] Example 4

[0066] Same as Example 1, except that the concentration of the added dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride methanol solution is 50 wt%.

[0067] Example 5

[0068] Same as Example 1, except that the number of organozirconium phosphate components in the organozirconium phosphate modified bitumen component is 5.

[0069] Example 6

[0070] Same as Example 1, except that the proportion of organozirconium phosphate in the organozirconium phosphate modified bitumen component is 15.

[0071] Example 7

[0072] Same as Example 1, except that the aqueous solution of sodium lignosulfonate is replaced with an aqueous solution of sodium 2,5-dimethylbenzenesulfonate of equal concentration and volume.

[0073] Example 8

[0074] Same as Example 1, except that the methanol solution of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride is replaced with a methanol solution of dodecyldimethyl(3-trimethoxysilyl)propyl)ammonium chloride of equal concentration and mass.

[0075] Comparative Example 1

[0076] A zirconium phosphate modified bitumen, by mass parts, has the following raw material composition: 10 parts zirconium phosphate and 100 parts matrix bitumen.

[0077] The preparation method of zirconium phosphate modified pitch includes the following steps:

[0078] After preheating the base asphalt to 160°C, zirconium phosphate is added in proportion, and the asphalt is sheared at high speed (4000 rpm) for 30 minutes at 160°C to obtain zirconium phosphate modified asphalt.

[0079] Comparative Example 2

[0080] Same as Example 1, except that the concentration of the added dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride methanol solution is 20 wt%.

[0081] Comparative Example 3

[0082] Same as Example 1, except that the concentration of the added dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride methanol solution is 60 wt%.

[0083] Comparative Example 4

[0084] Same as Example 1, except that the number of organozirconium phosphate components in the organozirconium phosphate pitch component is 3.

[0085] Comparative Example 5

[0086] Same as Example 1, except that the number of organozirconium phosphate components in the organozirconium phosphate modified bitumen component is 18.

[0087] Comparative Example 6

[0088] An organozirconium phosphate modified bitumen, by mass parts, has the following raw material composition: 10 parts organozirconium phosphate and 100 parts matrix bitumen.

[0089] The preparation method of organozirconium phosphate modified pitch includes the following steps:

[0090] S1. Preparation of organozirconium phosphate: Weigh 10 parts of zirconium phosphate into a beaker, add 100 parts of deionized water, and then add sodium hydroxide aqueous solution dropwise until the pH of the solution reaches 10. Stir at room temperature (1500 rpm) for 10 h, then filter and wash until the filtrate is neutral. Dry to obtain hydroxylated zirconium phosphate; Take 10 g of hydroxylated zirconium phosphate and disperse it in 100 g of deionized water, then add 100 g of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride methanol solution (40 wt%), stir (1500 rpm) for 3 h, then filter, wash, and vacuum dry to constant weight to obtain organozirconium phosphate;

[0091] S2. Preparation of organozirconium phosphate modified asphalt: After preheating the base asphalt to 160℃, organozirconium phosphate is added in proportion, and the asphalt is sheared at high speed (4000 rpm) for 30 minutes at 160℃ to obtain organozirconium phosphate modified asphalt.

[0092] Comparative Example 7

[0093] An organozirconium phosphate modified bitumen, by mass parts, has the following raw material composition: 10 parts organozirconium phosphate and 100 parts matrix bitumen.

[0094] The preparation method of organozirconium phosphate modified pitch includes the following steps:

[0095] S1. Disperse 10g of zirconium phosphate in 100g of deionized water, then add 100g of a methanol solution (40wt%) of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, and stir (1500rpm) for 3h; then add 75mL of an aqueous solution of sodium lignosulfonate (15wt%), stir at 70℃ (1500rpm) for 12h, filter, wash, and vacuum dry to constant weight to obtain organozirconium phosphate;

[0096] S2. Preparation of organozirconium phosphate modified asphalt: After preheating the base asphalt to 160℃, organozirconium phosphate is added in proportion, and the asphalt is sheared at high speed (4000 rpm) for 30 minutes at 160℃ to obtain organozirconium phosphate modified asphalt.

[0097] Test Example 1

[0098] To verify the relevant properties of the modified asphalt, the ductility of 70# base asphalt, the modified asphalt prepared in Examples 1-8, and Comparative Examples 1-7 was tested according to the national standard GB / T 4508-2010 (test temperature 5℃) to evaluate the low-temperature performance of the asphalt. Higher ductility indicates better extensibility, demonstrating superior low-temperature performance. In addition, ultraviolet aging tests were conducted on the asphalt samples (UV light intensity 800 W / m²). 2The asphalt samples were aged at 60℃ for 3 days. Temperature scanning experiments were conducted on the samples before and after aging using a dynamic shear rheometer to calculate the complex modulus aging index (CAI). This index was used to evaluate the asphalt's resistance to aging; a smaller CAI value indicates stronger resistance. The formula for calculating the aging index is as follows:

[0099]

[0100] In the formula: aging represents the post-aging index, and origin represents the pre-aging index.

[0101] The results of various performance tests are shown in Table 1:

[0102] Table 1

[0103]

[0104]

[0105] Based on the experimental data recorded in Table 1, comparing 70# base asphalt, Example 1, and Comparative Example 1, it can be seen that zirconium phosphate can improve the UV aging resistance of asphalt, but it will damage the ductility of asphalt under low temperature conditions. That is, the addition of zirconium phosphate will affect the low temperature performance of asphalt. The organozirconium phosphate obtained by secondary grafting surface modification can improve the low temperature performance and UV aging resistance of asphalt. The organozirconium phosphate modified asphalt has better UV aging resistance than the zirconium phosphate (unorganized) modified asphalt. This is attributed to the fact that the organo-organization solves the agglomeration problem of zirconium phosphate particles, greatly improves the dispersibility of zirconium phosphate in asphalt, and improves the compatibility between organozirconium phosphate and asphalt. Moreover, the uniform dispersion of the layered structure is conducive to improving its absorption and shielding effect of UV radiation.

[0106] Comparing Examples 1, 3, and 4 with Comparative Examples 2 and 3, it can be seen that during the surface modification of zirconium phosphate, if the concentration of the methanol solution of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride is too low, the surface modification of zirconium phosphate is insufficient, affecting the organophosphate effect and resulting in the organophosphate zirconium not significantly improving the low-temperature performance and UV aging resistance of asphalt; if the concentration of the methanol solution of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride is too high, its improvement on asphalt performance is limited. Considering the preparation cost, its concentration should not be too high.

[0107] Comparing Examples 1, 5, and 6 with Comparative Examples 4 and 5, it can be seen that in the preparation process of organozirconium phosphate modified asphalt, if the amount of organozirconium phosphate is too low, the improvement effect on the low-temperature performance and UV aging resistance of the asphalt is poor. If the amount of organozirconium phosphate is too high, the improvement on the low-temperature performance of the asphalt is limited. Considering the preparation cost, its dosage should not be too high.

[0108] Comparing Examples 1, 2, and 7, it can be seen that using sodium lignosulfonate with a structure rich in phenolic hydroxyl groups as an anionic surfactant is more beneficial to improving the anti-aging properties of organozirconium phosphate modified asphalt, while using sodium dodecyl sulfate with a long-chain structure as an anionic surfactant has a more significant effect on improving the low-temperature performance of organozirconium phosphate modified asphalt.

[0109] Comparing Examples 1 and 8, it can be seen that when the ammonium salt organosiloxane is dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, a better organication effect can be achieved, and the improvement on the low-temperature performance and UV aging resistance of asphalt is more obvious.

[0110] Comparing Example 1 and Comparative Example 6, it can be seen that secondary grafting on the surface of zirconium phosphate is beneficial to further improve the low-temperature performance and anti-aging properties of organozirconium phosphate modified asphalt.

[0111] Comparing Example 1 and Comparative Example 7, it can be seen that hydroxylation treatment of zirconium phosphate is beneficial to improving the organification effect of zirconium phosphate, thereby increasing the low-temperature performance and anti-aging properties of asphalt.

[0112] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An organozirconium phosphate modified asphalt with low-temperature ductility and UV aging resistance, characterized in that, By weight, the raw materials include: 100 parts of base bitumen and 5-15 parts of organophosphate zirconium; The organozirconium phosphate is obtained by sequentially surface-modifying zirconium phosphate with ionic organosiloxane and anionic surfactant; The ionic organosiloxane is an ammonium salt organosiloxane; the anionic surfactant includes sodium alkyl sulfonate, sodium alkyl aryl sulfonate, sodium alkyl sulfate, or sodium lignin sulfonate. The preparation steps of the organozirconium phosphate include: hydroxyl modification of zirconium phosphate to obtain hydroxylated zirconium phosphate; dispersing the hydroxylated zirconium phosphate in water, then adding a methanol solution of an ionic organosiloxane, stirring for 2-4 hours, then adding an aqueous solution of an anionic surfactant, heating and stirring for 10-12 hours to obtain the organozirconium phosphate. The hydroxylation modification of zirconium phosphate to obtain hydroxylated zirconium phosphate includes: mixing zirconium phosphate and water, adjusting the pH of the mixed solution to 9-11, and stirring for 8-10 hours to obtain the hydroxylated zirconium phosphate. The ammonium salt organosiloxane is one of dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, dodecyldimethyl(3-trimethoxysilyl)propyl]ammonium chloride, and dimethyldodecyl[3-(triethoxysilyl)propyl]ammonium chloride; The ratio of the amount of hydroxylated zirconium phosphate, water, methanol solution of ionic organosiloxane, and aqueous solution of anionic surfactant is 1g:8-12g:8-12g:5-10mL. The concentration of the methanol solution of the ionic organosiloxane is 30-50 wt%; the concentration of the aqueous solution of the anionic surfactant is 10-20 wt%. The heating and stirring temperature is 60–80°C.

2. The method for preparing organozirconium phosphate modified asphalt with low-temperature ductility and UV aging resistance as described in claim 1, characterized in that, Includes the following steps: The base asphalt is preheated to 150-170°C and then organozirconium phosphate is added. The asphalt is then subjected to high-speed shearing at 150-170°C for 30-60 minutes to obtain the organozirconium phosphate modified asphalt.

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