High performance tack coat material for polyurethane porous elastic mixture pavement and preparation method thereof

Abstract

This invention relates to the field of road materials technology, specifically to a high-performance tack coat material for polyurethane porous elastic mixture pavements and its preparation method. The raw material components of the high-performance tack coat material include: functional polyurethane, asphalt, emulsifier, and water; the functional polyurethane is obtained by reacting a hydrolyzable isocyanate, a hydrolyzable polyol, and a strong hydrogen-bonding chain extender. The high-performance tack coat material prepared by this invention possesses excellent shear strength and hydrolysis resistance, and can establish a chemical bond with the upper polyurethane porous elastic mixture pavement and form strong hydrogen bonds with the underlying asphalt mixture, thereby significantly improving interlayer adhesion and enhancing the stability of the pavement structure. Furthermore, due to the elastic effect of the polyurethane in the high-performance tack coat material, it can buffer the traffic load transmitted from the road surface, further reducing the possibility of interlayer failure.

Description

Technical Field

[0001] This invention relates to the field of road materials technology, specifically to a high-performance tack coat material for polyurethane porous elastic mixture pavement and its preparation method. Background Technology

[0002] Polyurethane porous elastic composite (PERS), as a novel environmentally friendly pavement material, not only achieves the resource utilization of solid waste by incorporating polyurethane adhesives and waste tire rubber particles, but also boasts a noise reduction effect far exceeding traditional low-noise pavement technologies due to its large-pore structure and elastic vibration damping properties, making it one of the key technologies for promoting the construction of "ultra-quiet" traffic environments. Furthermore, its conventional construction process does not require high-temperature heating, significantly reducing carbon emissions, and it has broad application prospects in urban expressways, scenic roads, and other scenarios.

[0003] However, under harsh conditions such as heavy traffic, high-temperature immersion, and freeze-thaw cycles, PERS pavement frequently experiences interlayer debonding in the wheel track area, leading to rapidly developing potholes, which has become a key bottleneck restricting the long-term service of PERS pavement. Related research indicates that the debonding mechanism of the PERS layer-tack coat-asphalt subbase can be summarized as a multi-factor coupling effect: first, the dynamic horizontal shear force generated by heavy loads and braking exceeds the interlayer bond strength, leading to interfacial shear failure; second, after rainwater intrusion, water molecules penetrate through pores to the interface, weakening the physical adhesion between the tack coat material and the asphalt components; and third, freeze-thaw cycles cause repeated interfacial ice expansion stress, exacerbating crack propagation. This complex interlayer debonding mechanism places high demands on the performance of the tack coat material. Traditional interlayer adhesives such as SBS-modified emulsified asphalt and rubber-modified emulsified asphalt, while possessing certain bonding and waterproofing properties, have relatively fixed compositions and structures, making it difficult to effectively respond to and customize performance for the interfacial failure mechanism under the "temperature-water-force" coupling effect. This results in significant degradation of the bond performance between the PERS pavement and the asphalt layer, failing to meet the requirements for long-term service.

[0004] Therefore, there is an urgent need to develop high-performance interlayer bonding technology to improve the durability and service life of PERS pavement under the coupled effects of multiple factors such as temperature, water and force. Summary of the Invention

[0005] In view of this, the present invention proposes a high-performance tack coat material for polyurethane porous elastic mixture pavement and its preparation method. By enhancing the properties of the tack coat material itself and the bonding performance between the tack coat material and the upper and lower layers of the PERS pavement, the durability of the PERS pavement is improved. The technical solution of the present invention is implemented as follows:

[0006] In a first aspect, the present invention proposes a high-performance tack coat material for polyurethane porous elastic mixture pavement, the raw material components of which include: functional polyurethane, asphalt, emulsifier and water; the functional polyurethane is obtained by reacting hydrolytically resistant isocyanate, hydrolytically resistant polyol and strong hydrogen bond chain extender.

[0007] Specifically, the functional polyurethane is used to form chemical bonds with the unreacted isocyanate groups in the upper layer of polyurethane porous elastic mixture and to form strong hydrogen bonds with the polar groups such as hydroxyl and carboxyl groups contained in the asphalt in the lower layer of asphalt mixture.

[0008] Preferably, the weight ratio of the functional polyurethane, asphalt, emulsifier and water is (3-6):100:(1-6):(25-100).

[0009] Preferably, the weight ratio of the hydrolysis-resistant polyol, the strong hydrogen bond chain extender, and the hydrolysis-resistant isocyanate is 100:(6.5-17.4):(20-53.2).

[0010] Preferably, the hydrolysis-resistant isocyanate includes one or more of hexamethylene diisocyanate trimer, isophorone diisocyanate trimer, phenyl diisocyanate, and carbodiimide-modified diphenylmethane diisocyanate.

[0011] Preferably, the hydrolysis-resistant polyol has a functionality of 2-3 and a number-average molecular weight of 1000-4000.

[0012] Specifically, the functionality of the hydrolyzable polyol 2-3 ensures that a moderately cross-linked elastic network is formed when reacting with the hydrolyzable isocyanate. This avoids the situation where only a linear structure can be formed when the functionality is 1, resulting in insufficient material strength and poor shear resistance. It also avoids the situation where the cross-linking is too dense when the functionality is >3, causing the material to become brittle and lose its elasticity, thus failing to achieve the function of buffering road surface loads and reducing interlayer damage.

[0013] More preferably, the hydrolysis-resistant polyol includes one or more of polypropylene glycol, polypropylene triol, and polytetrahydrofuran ether glycol.

[0014] More preferably, the hydrolysis-resistant polyol includes polyoxypropylene triol with a number average molecular weight of 3000-4000 or polytetrahydrofuran ether diol with a number average molecular weight of 1000-2000.

[0015] Preferably, the ratio of the total molar number of isocyanate groups in the hydrolytically resistant isocyanate to the total molar number of active hydrogens in the hydrolytically resistant polyol and the strong hydrogen bond chain extender is 0.95-0.98.

[0016] Specifically, the isocyanate index R value of the synthesized functional polyurethane is 0.95-0.98; R value is the isocyanate index, which refers to the ratio of the total molar number of isocyanate groups (-NCO) contained in the hydrolyzable isocyanate during the synthesis of the functional polyurethane to the total molar number of total active hydrogen (-H) contained in the hydrolyzable polyol and strong hydrogen bond chain extender. This invention determines the type of terminal groups and the residual hydroxyl content of the functional polyurethane molecular chain after the reaction by controlling the molar ratio of -NCO to total -H, achieving an excess of hydroxyl groups.

[0017] More preferably, the hydroxyl value at the end of the molecular chain of the functional polyurethane is 20~100 mg KOH / g.

[0018] Specifically, according to the hydroxyl value formula: hydroxyl value = (functionality × 56100) / number average molecular weight, it can be seen that the hydroxyl value of polyols (1000-2000 number average molecular weight corresponds to functionality 2, and 3000-4000 number average molecular weight corresponds to functionality 3) is already in the range of 42~112.2 mg KOH / g. In conjunction with the isocyanate index (R=0.95-0.98), the terminal hydroxyl value of functional polyurethane can be controlled at 20~100 mg KOH / g.

[0019] Meanwhile, the molecular chain length of polyether polyols in this molecular range is moderate, which avoids the problem of excessively short chains (leading to brittle materials with no buffering capacity) when the molecular weight is <1000, and also avoids the problem of excessively long chains (low hydroxyl density) (insufficient reactivity, insufficient crosslinking, and reduced shear strength) when the molecular weight is >4000. In addition, it can be well compatible with asphalt emulsions (avoiding delamination and demulsification).

[0020] Preferably, the strong hydrogen bond chain extender includes one or more of adipic acid dihydrazide and isophthalic acid dihydrazide.

[0021] Specifically, the strong hydrogen bond chain extender is a compound containing multiple amide or urea groups in its molecule. It can form strong hydrogen bonds with polar groups such as hydroxyl and carboxyl groups contained in the asphalt in the underlying asphalt mixture through its amide or urea groups, thereby enhancing the adhesion performance between the tack coat material and the asphalt layer; and preferably, it is an acylhydrazine chain extender.

[0022] In a second aspect, the present invention provides a method for preparing a high-performance adhesive layer material as described in the first aspect, characterized by comprising the following steps:

[0023] S1. Under inert gas protection, a hydrolyzable polyol and a strong hydrogen bond chain extender are heated and vacuum dehydrated; after cooling, a hydrolyzable isocyanate is added, and the reaction is maintained at the temperature to obtain a functional polyurethane.

[0024] S2. Heat the asphalt, dissolve the emulsifier in water and heat it, add the hot emulsifier aqueous solution to the hot asphalt under high-speed shearing, and shear emulsify to obtain asphalt emulsion;

[0025] S3. Add the functional polyurethane obtained in step S1 to the asphalt emulsion obtained in step S2, and stir continuously until it is mixed evenly to obtain the high-performance adhesive material.

[0026] Thirdly, the present invention provides an application of the high-performance tack coat material as described in the first aspect, the high-performance tack coat material being used to bond a polyurethane porous elastic mixture upper layer to an asphalt mixture lower layer.

[0027] Compared with the prior art, the advantages of the present invention are as follows:

[0028] (1) The high-performance adhesive material of the present invention has excellent bonding performance. Through the dual effects of chemical bonding and physical adsorption, the bonding strength with the upper and lower layers is greatly improved. The interlayer shear strength and pull-out strength are significantly higher than those of traditional adhesive materials.

[0029] (2) The high-performance adhesive material of the present invention has excellent durability. Due to the comprehensive introduction of hydrolysis resistance and high strength characteristics from the molecular structure, the adhesive material has a very high strength retention rate after immersion in water. It can effectively resist water damage and freeze-thaw cycles, and solve the core pain point of interlayer debonding caused by water intrusion in PERS pavement.

[0030] (3) The high-performance adhesive material of the present invention has high toughness and elasticity. The strong hydrogen bonding and elastic network structure in the polyurethane molecular chain endow the adhesive material with good toughness and deformation recovery ability, which can buffer traffic load and further reduce the risk of stress concentration and damage between layers. Detailed Implementation

[0031] The embodiments of the present invention are described in detail below. These embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0032] It should be noted that, compared to traditional interlayer adhesives, polyurethane-modified emulsified asphalt, with its designability and structural diversity of polyurethane molecular chains, offers the possibility of targeted solutions to interlayer debonding problems. This invention, by introducing hydrolysis-resistant groups into the polyurethane chain segments, can specifically resist water erosion and interface damage; the introduction of strong hydrogen-bonding groups can enhance the material's resistance to heavy-load deformation, while simultaneously strengthening the interfacial bond strength with the PERS layer and the asphalt sublayer, achieving a functional leap from "passive protection" to "active adaptation."

[0033] Specifically, this invention focuses on the debonding mechanism of PERS layers, targeting the key causes of interfacial failure. It involves targeted design of polyurethane for use in the preparation of tack coat materials, effectively improving the tack coat material's resistance to temperature-water-force coupling, thereby significantly extending the service life of PERS pavements. The high-performance tack coat material prepared by this invention possesses excellent shear strength and hydrolysis resistance. It also establishes chemical bonds with the upper polyurethane porous elastic mixture pavement and forms strong hydrogen bonds with the lower asphalt mixture, thus significantly improving interlayer adhesion and enhancing pavement structural stability. Furthermore, the elasticity of polyurethane in the high-performance tack coat material buffers the traffic load transmitted from the road surface, further reducing the possibility of interlayer failure.

[0034] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0035] In this document, the terms “containing,” “comprising,” or “including” are open-ended expressions, meaning they include the contents specified in this invention but do not exclude other aspects.

[0036] In this document, the terms “optional,” “optionally,” or “optional” generally refer to an event or condition that may, but may not, occur, and the description includes both cases in which the event or condition occurs and cases in which the event or condition does not occur.

[0037] This invention specifically provides a method for preparing a high-performance tack coat material for polyurethane porous elastic mixture pavements, comprising the following steps:

[0038] (1) Preparation of functional polyurethane: Under inert gas protection, the hydrolysis-resistant polyol and strong hydrogen bond chain extender are first dehydrated under vacuum conditions of 110-120℃ for 2-3h; then, the system is cooled to 75-85℃, and the hydrolysis-resistant isocyanate is added according to the stoichiometric ratio of isocyanate index R value of 0.95-0.98. The reaction is kept at the temperature for 3-4h to ensure that the molecular chain ends are hydroxyl groups after the reaction is complete, and functional polyurethane is obtained.

[0039] (2) Preparation of asphalt emulsion: Heat asphalt to 130-160℃ to a fluid state, dissolve emulsifier in water and heat to 60-65℃, add hot emulsifier aqueous solution to hot asphalt under high-speed shearing conditions, shear emulsify for 8-12 minutes to obtain asphalt emulsion;

[0040] (3) Preparation of high-performance adhesive layer material: Cool the functional polyurethane obtained in step (1) to 40-50°C, and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions. Continue stirring for 25-35 minutes to make it evenly mixed, and the high-performance adhesive layer material is obtained.

[0041] Preferably, in step (3), the stirring speed is 500-700 rpm.

[0042] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0043] All materials used in this invention were purchased from the market. Specifically, polytetrahydrofuran ether diol, polypropylene triol, and adipic acid dihydrazide were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.; carbodiimide-modified diphenylmethane diisocyanate (model WANNATE® CDMDI-100H, isocyanate content 30 wt%) was purchased from Wanhua Chemical Group Co., Ltd.; 70# asphalt was purchased from Shandong; and slow-cracking fast-setting cationic emulsifier (model WSG-B03) was purchased from Shanghai Wanzhao Fine Chemical Co., Ltd.

[0044] Example 1

[0045] This embodiment provides a method for preparing a high-performance tack coat material for polyurethane porous elastic mixture pavement, with an isocyanate index R value of 0.95, specifically including the following steps:

[0046] (1) Preparation of functional polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polytetrahydrofuran ether diol with a molecular weight of 2000) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃ and 26.6g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added, at which time the isocyanate index R value was 0.95; the reaction was kept at the temperature for 4h to obtain functional polyurethane;

[0047] Specifically, the R value is calculated as follows: 100g of polytetrahydrofuran ether diol with a molecular weight of 2000 has an active hydrogen equivalent of 0.1, and 8.7g of adipate dihydrazide has an active hydrogen equivalent of 0.1, meaning the total active hydrogen equivalent is 0.2; the -NCO content of carbodiimide-modified diphenylmethane diisocyanate is 30%, and the molar mass of the -NCO group is 42g / mol, so the equivalent weight of the isocyanate is 42 / 30% = 140g / eq, meaning the total isocyanate group equivalent is 26.6 / 140 = 0.19; therefore, R = 0.19 / 0.2 = 0.95;

[0048] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0049] (3) Preparation of high-performance tack coat material: Cool the functional polyurethane obtained in step (1) to 50°C, take 4g of functional polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining high-performance polyurethane modified emulsified asphalt tack coat material.

[0050] Example 2

[0051] This embodiment provides a method for preparing a high-performance tack coat material for polyurethane porous elastic mixture pavement, with an isocyanate index R value of 0.98, specifically including the following steps:

[0052] (1) Preparation of functional polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polytetrahydrofuran ether diol with a molecular weight of 2000) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃ and 27.4g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added. At this time, the isocyanate index R value was 0.98 (calculated in the same way as in Example 1); the reaction was kept at the temperature for 4h to obtain functional polyurethane;

[0053] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0054] (3) Preparation of high-performance tack coat material: Cool the functional polyurethane obtained in step (1) to 50°C, take 4g of functional polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining high-performance polyurethane modified emulsified asphalt tack coat material.

[0055] Example 3

[0056] This embodiment provides a method for preparing a high-performance tack coat material for polyurethane porous elastic mixture pavement, using a difunctional polyol with a number-average molecular weight of 1000, and specifically includes the following steps:

[0057] (1) Preparation of functional polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polytetrahydrofuran ether diol with a molecular weight of 1000) and 17.4g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃ and 53.2g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added. At this time, the isocyanate index R value was 0.95 (calculated in the same way as in Example 1); the reaction was kept at the temperature for 4h to obtain functional polyurethane;

[0058] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0059] (3) Preparation of high-performance tack coat material: Cool the functional polyurethane obtained in step (1) to 50°C, take 4g of functional polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining high-performance polyurethane modified emulsified asphalt tack coat material.

[0060] Example 4

[0061] This embodiment provides a method for preparing a high-performance tack coat material for polyurethane porous elastic mixture pavement, using a trifunctional polyol with a number-average molecular weight of 3000, and specifically includes the following steps:

[0062] (1) Preparation of functional polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polyoxypropylene triol with a molecular weight of 3000) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃ and 26.6g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added. At this time, the isocyanate index R value was 0.95 (calculated in the same way as in Example 1); the reaction was kept at the temperature for 4h to obtain functional polyurethane;

[0063] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0064] (3) Preparation of high-performance tack coat material: Cool the functional polyurethane obtained in step (1) to 50°C, take 4g of functional polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining high-performance polyurethane modified emulsified asphalt tack coat material.

[0065] Example 5

[0066] This embodiment provides a method for preparing a high-performance tack coat material for polyurethane porous elastic mixture pavement, using a trifunctional polyol with a number-average molecular weight of 4000, and specifically includes the following steps:

[0067] (1) Preparation of functional polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polyoxypropylene triol with a molecular weight of 4000) and 6.5g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃ and 20g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added. At this time, the isocyanate index R value was 0.95 (calculated in the same way as in Example 1); the reaction was kept at the temperature for 4h to obtain functional polyurethane;

[0068] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0069] (3) Preparation of high-performance tack coat material: Cool the functional polyurethane obtained in step (1) to 50°C, take 4g of functional polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining high-performance polyurethane modified emulsified asphalt tack coat material.

[0070] Example 6

[0071] This embodiment provides a method for preparing a high-performance tack coat material for polyurethane porous elastic mixture pavement, specifically including the following steps:

[0072] (1) Preparation of functional polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (molecular weight of 2000 polytetrahydrofuran ether diol) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 120℃ under vacuum for 2h; then, the system was cooled to 85℃ and 26.6g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added. At this time, the isocyanate index R value was 0.95 (calculated in the same way as in Example 1); the reaction was kept at the temperature for 4h to obtain functional polyurethane;

[0073] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 130℃ and made into a fluid state. 1g of slow-cracking and fast-setting cationic emulsifier was dissolved in 25g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0074] (3) Preparation of high-performance tack coat material: Cool the functional polyurethane obtained in step (1) to 40°C, take 3g of functional polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 25min to make it evenly mixed, thus obtaining high-performance polyurethane modified emulsified asphalt tack coat material.

[0075] Example 7

[0076] This embodiment provides a method for preparing a high-performance tack coat material for polyurethane porous elastic mixture pavement, specifically including the following steps:

[0077] (1) Preparation of functional polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polytetrahydrofuran ether diol with a molecular weight of 2000) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 3h; then, the system was cooled to 75℃ and 26.6g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added. At this time, the isocyanate index R value was 0.95 (calculated in the same way as in Example 1); the reaction was kept at the temperature for 3h to obtain functional polyurethane;

[0078] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 160℃ and made into a fluid state. 6g of slow-cracking and fast-setting cationic emulsifier was dissolved in 100g of water and heated to 65℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 8min to obtain asphalt emulsion.

[0079] (3) Preparation of high-performance tack coat material: Cool the functional polyurethane obtained in step (1) to 50°C, take 6g of functional polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 35min to make it evenly mixed, thus obtaining high-performance polyurethane modified emulsified asphalt tack coat material.

[0080] Comparative Example 1

[0081] This comparative example provides a method for preparing a common emulsified asphalt tack coat material, including the following steps:

[0082] 100g of 70# road petroleum asphalt was heated to 160℃ and made into a fluid state. 3g of slow-cracking and fast-setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 8 minutes to obtain ordinary emulsified asphalt tack coat material.

[0083] Comparative Example 2

[0084] This comparative example provides a method for preparing an SBS-modified asphalt tack coat material, including the following steps:

[0085] SBS modified asphalt, prepared by high-speed shearing of 100g of 70# road petroleum asphalt and 5g of linear SBS modifier, was heated to 160℃ and became fluid. 3g of slow-cracking and fast-setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions, and shearing emulsification was carried out for 8 minutes to obtain SBS modified emulsified asphalt tack coat material.

[0086] Comparative Example 3

[0087] This comparative example provides a method for preparing a polyurethane-modified emulsified asphalt tack coat material, which differs from Example 1 in that the isocyanate index R value is 1.1, and includes the following steps:

[0088] (1) Preparation of comparative functional polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polytetrahydrofuran ether diol with a molecular weight of 2000) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃ and 30.8g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added. At this time, the isocyanate index R value was 1.1 (calculated in the same way as in Example 1); the reaction was kept at the temperature for 4h to obtain comparative functional polyurethane with -NCO groups at both ends;

[0089] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0090] (3) Preparation of high-performance tack coat material: Cool the contrast functional polyurethane obtained in step (1) to 50°C, take 4g of contrast functional polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the contrast polyurethane modified emulsified asphalt tack coat material.

[0091] Comparative Example 4

[0092] This comparative example provides a method for preparing a common polyurethane-modified emulsified asphalt tack coat material, which differs from Example 1 in that it uses common polyols, common chain extenders, and common isocyanates, and includes the following steps:

[0093] (1) Preparation of ordinary polyurethane: Under inert gas protection, 100g of ordinary polyol (polyethylene adipate diol with a molecular weight of 2000) and 4.5g of ordinary chain extender (butanediol) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 23.8g of ordinary isocyanate (diphenylmethane diisocyanate) was added according to the stoichiometric ratio of isocyanate index R value of 0.95 (calculated in the same way as in Example 1). The reaction was kept at the temperature for 4h to ensure that the molecular chain ends were hydroxyl groups after the reaction was complete, thus obtaining ordinary polyurethane;

[0094] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0095] (3) Preparation of ordinary tack coat material: Cool the ordinary polyurethane obtained in step (1) to 50°C, take 4g of ordinary polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining ordinary polyurethane modified emulsified asphalt tack coat material.

[0096] Comparative Example 5

[0097] This comparative example provides a method for preparing a hydrolysis-resistant polyurethane-modified emulsified asphalt tack coat material. The difference from Example 1 lies in the use of common polyols, common chain extenders, and hydrolysis-resistant isocyanates, and includes the following steps:

[0098] (1) Preparation of hydrolysis-resistant polyurethane: Under inert gas protection, 100g of ordinary polyol (polyethylene adipate diol with a molecular weight of 2000) and 4.5g of ordinary chain extender (butanediol) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 26.6g of hydrolysis-resistant isocyanate (carbodiimide-modified diphenylmethane diisocyanate) was added according to the stoichiometric ratio of isocyanate index R value of 0.95 (calculated in the same way as in Example 1). The reaction was kept at the temperature for 4h to ensure that the molecular chain ends are hydroxyl groups after the reaction is complete, thus obtaining hydrolysis-resistant polyurethane;

[0099] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0100] (3) Preparation of hydrolysis resistant tack coat material: Cool the hydrolysis resistant polyurethane obtained in step (1) to 50°C, take 4g of hydrolysis resistant polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the hydrolysis resistant polyurethane modified emulsified asphalt tack coat material.

[0101] Comparative Example 6

[0102] This comparative example provides a method for preparing a hydrolysis-resistant polyurethane-modified emulsified asphalt tack coat material. The difference from Example 1 lies in the use of a hydrolysis-resistant polyol, a common chain extender, and a common isocyanate, and includes the following steps:

[0103] (1) Preparation of hydrolysis-resistant polyurethane: Under inert gas protection, 100g of hydrolysis-resistant polyol (polytetrahydrofuran ether diol with a molecular weight of 2000) and 4.5g of common chain extender (butanediol) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 23.8g of common isocyanate (diphenylmethane diisocyanate) was added according to the stoichiometric ratio of isocyanate index R value of 0.95 (calculated in the same way as in Example 1). The reaction was kept at the temperature for 4h to ensure that the molecular chain ends are hydroxyl groups after the reaction is complete, thus obtaining hydrolysis-resistant polyurethane;

[0104] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0105] (3) Preparation of hydrolysis resistant tack coat material: Cool the hydrolysis resistant polyurethane obtained in step (1) to 50°C, take 4g of hydrolysis resistant polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the hydrolysis resistant polyurethane modified emulsified asphalt tack coat material.

[0106] Comparative Example 7

[0107] This comparative example provides a method for preparing a strongly hydrogen-bonded polyurethane modified emulsified asphalt tack coat material. The difference from Example 1 is the use of a common polyol, a strong hydrogen-bonded chain extender, and a common isocyanate, and includes the following steps:

[0108] (1) Preparation of strong hydrogen bond polyurethane: Under inert gas protection, 100g of ordinary polyol (polyethylene adipate diol with a molecular weight of 2000) and 8.7g of strong hydrogen bond chain extender (adipate dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 23.8g of ordinary isocyanate (diphenylmethane diisocyanate) was added according to the stoichiometric ratio of isocyanate index R value of 0.95 (calculated in the same way as in Example 1). The reaction was kept at the temperature for 4h to ensure that the molecular chain ends were hydroxyl groups after the reaction was complete, thus obtaining strong hydrogen bond polyurethane;

[0109] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0110] (3) Preparation of strong hydrogen bond adhesive layer material: Cool the strong hydrogen bond polyurethane obtained in step (1) to 50°C, take 4g of strong hydrogen bond polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the strong hydrogen bond polyurethane modified emulsified asphalt adhesive layer material.

[0111] Comparative Example 8

[0112] This comparative example provides a method for preparing a polyurethane-modified emulsified asphalt tack coat material. Compared with Example 1, it uses a hydrolysis-resistant polyol with 3 functionalities and a molecular weight of 5000, and includes the following steps:

[0113] (1) Preparation of comparative polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polypropylene triol with a molecular weight of 5000) and 5.4g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 16g of hydrolyzable isocyanate (carbodiimide-modified diphenylmethane diisocyanate) was added, at which time the isocyanate index R value was 0.95 (calculated in the same way as in Example 1). The reaction was kept at the temperature for 4h to obtain comparative polyurethane;

[0114] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0115] (3) Preparation of contrast tack coat material: Cool the contrast polyurethane obtained in step (1) to 50°C, take 4g of contrast polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the high contrast polyurethane modified emulsified asphalt tack coat material.

[0116] Comparative Example 9

[0117] This comparative example provides a method for preparing a polyurethane-modified emulsified asphalt tack coat material. Compared with Example 1, it uses a hydrolysis-resistant polyol with a molecular weight of 650 and includes the following steps:

[0118] (1) Preparation of comparative polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (polypropylene triol with a molecular weight of 650) and 40g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 122.3g of hydrolyzable isocyanate (carbodiimide-modified diphenylmethane diisocyanate) was added, at which point the isocyanate index R value was 0.95. The reaction was maintained at this temperature for 4h to obtain comparative polyurethane;

[0119] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0120] (3) Preparation of contrast tack coat material: Cool the contrast polyurethane obtained in step (1) to 50°C, take 4g of contrast polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the high contrast polyurethane modified emulsified asphalt tack coat material.

[0121] Comparative Example 10

[0122] This comparative example provides a method for preparing a polyurethane-modified emulsified asphalt tack coat material, which differs from Example 1 in that the isocyanate index R value is 0.9, and includes the following steps:

[0123] (1) Comparative preparation of polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (molecular weight 2000 polytetrahydrofuran ether diol) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 25.5g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added. At this time, the isocyanate index R value was 0.9 (calculated in the same way as in Example 1). The reaction was kept at the temperature for 4h to obtain high-performance polyurethane with -NCO groups at both ends;

[0124] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in 50g of water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0125] (3) Preparation of contrast tack coat material: Cool the contrast polyurethane obtained in step (1) to 50°C, take 4g of contrast polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the contrast polyurethane modified emulsified asphalt tack coat material.

[0126] Comparative Example 11

[0127] This comparative example provides a method for preparing a polyurethane-modified emulsified asphalt tack coat material, using a hydrolysis-resistant polyol, a strong hydrogen-bonding chain extender, and a common isocyanate, including the following steps:

[0128] (1) Preparation of comparative polyurethane: Under inert gas protection, 100g of hydrolysis-resistant polyol (polytetrahydrofuran ether diol with a molecular weight of 2000) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110°C under vacuum for 2h; then, the system was cooled to 80°C, and 23.8g of ordinary isocyanate (diphenylmethane diisocyanate) was added according to the stoichiometric ratio of isocyanate index R value of 0.95 (calculated in the same way as in Example 1), and the reaction was kept at the temperature for 4h to obtain comparative polyurethane;

[0129] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0130] (3) Preparation of contrast tack coat material: Cool the contrast polyurethane obtained in step (1) to 50°C, take 4g of contrast polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the contrast polyurethane modified emulsified asphalt tack coat material.

[0131] Comparative Example 12

[0132] This comparative example provides a method for preparing a polyurethane-modified emulsified asphalt tack coat material, using a common polyol, a strong hydrogen-bonding chain extender, and a hydrolysis-resistant isocyanate, including the following steps:

[0133] (1) Preparation of comparative polyurethane: Under inert gas protection, 100g of ordinary polyol (polyethylene adipate diol with a molecular weight of 2000) and 8.7g of strong hydrogen bond chain extender (adipic acid dihydrazide) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 26.6g of hydrolytically resistant isocyanate (carbodiimide-modified diphenylmethane diisocyanate) was added according to the stoichiometric ratio of isocyanate index R value of 0.95 (calculated in the same way as in Example 1), and the reaction was kept at the temperature for 4h to obtain comparative polyurethane;

[0134] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0135] (3) Preparation of contrast tack coat material: Cool the contrast polyurethane obtained in step (1) to 50°C, take 4g of contrast polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the contrast polyurethane modified emulsified asphalt tack coat material.

[0136] Comparative Example 13

[0137] This comparative example provides a method for preparing a comparative polyurethane-modified emulsified asphalt tack coat material, using hydrolysis-resistant polyols, common chain extenders, and hydrolysis-resistant isocyanates, including the following steps:

[0138] (1) Preparation of comparative polyurethane: Under inert gas protection, 100g of hydrolyzable polyol (molecular weight of 2000 polytetrahydrofuran ether diol) and 4.5g of common chain extender (butanediol) were first dehydrated at 110℃ under vacuum for 2h; then, the system was cooled to 80℃, and 26.6g of hydrolyzable isocyanate (carbodiimide modified diphenylmethane diisocyanate) was added according to the stoichiometric ratio of isocyanate index R value of 0.95 (calculated in the same way as in Example 1), and the reaction was kept at the temperature for 4h to obtain comparative polyurethane;

[0139] (2) Preparation of asphalt emulsion: 100g of 70# asphalt was heated to 150℃ and made into a fluid state. 3g of slow cracking and fast setting cationic emulsifier was dissolved in water and heated to 60℃. The hot emulsifier aqueous solution was added to the hot asphalt under high-speed shearing conditions and sheared and emulsified for 12min to obtain asphalt emulsion.

[0140] (3) Preparation of contrast tack coat material: Cool the contrast polyurethane obtained in step (1) to 50°C, take 4g of contrast polyurethane and slowly add it to the asphalt emulsion obtained in step (2) under stirring conditions, and continue stirring for 30min to make it evenly mixed, thus obtaining the contrast polyurethane modified emulsified asphalt tack coat material.

[0141] Performance Tests and Results

[0142] The inventors used the tack coat materials prepared in the above examples and comparative examples. After the emulsified asphalt demulsified and cured, fatigue-healing tests were conducted using a dynamic shear rheometer according to the literature "Green synthesis of polyurethane with reversible oxime-urethane bond to enhance the self-healing properties of asphalt binder at room temperature". The fatigue test was terminated when the modulus of the sample dropped to 70% of the initial modulus. The samples were then kept at 25°C for 30 minutes to obtain the fatigue healing rate of different tack coat materials. The calculation results are shown in Table 1. The change in fatigue recovery rate is mainly affected by the density of strong hydrogen bonds, molecular weight, and cross-linking structure in the polyurethane molecular chain.

[0143] Table 1 Fatigue recovery rate of different tack coat materials

[0144]

[0145] The results showed that Examples 1 and 2, due to the use of a fully hydrolysis-resistant system (hydrolysis-resistant isocyanate + hydrolysis-resistant polyol + strong hydrogen bond chain extender) and an R value controlled between 0.95 and 0.98, formed an ideal dynamic reversible hydrogen bond network, exhibiting the best fatigue recovery ability. Example 3 used a diol with a molecular weight of 1000, which had a higher proportion of hard segments and a high hydrogen bond density, but slightly lower chain segment mobility, resulting in a slight decrease in the recovery rate. Examples 4 and 5 used trifunctional polyols (molecular weight 3000-4000), which moderately crosslinked to improve strength but restricted chain segment movement, resulting in a slight decrease in the recovery rate.

[0146] Comparative Examples 1 and 2 had the lowest recovery rates due to the complete lack of hydrogen bond repair mechanisms in polyurethane. Comparative Example 3, due to the use of an R=1.1 to synthesize an NCO-terminated polyurethane, experienced side reactions with water during the emulsification stage, leading to gelation and demulsification, preventing the formation of a stable adhesive layer. Comparative Example 4, using ordinary components, lacked strong hydrogen bond building capabilities. Comparative Examples 5 and 6, using only partial high-performance components, showed gradually improved recovery rates. Comparative Example 7 achieved some recovery capability through a strong hydrogen bond chain extender. Comparative Example 8, with its 5000 molecular weight polyol chain entanglement, and Comparative Example 9, with its 650 molecular weight polyol chain length being insufficient, both suffered from weakened hydrogen bond reconstruction capabilities. Comparative Example 10, with an R=0.9, had an excessively low molecular weight and insufficient hydrogen bond density. Comparative Examples 11 and 12, lacking only a single high-performance component, had performance close to the examples. Comparative Example 13, using ordinary chain extenders, had a slightly lower recovery rate due to a reduced number of strong hydrogen bonds.

[0147] The inventors continued to use the tack coat materials prepared in the above examples and comparative examples, and prepared interlaminar shear specimens according to the literature "Cohesion Performance of Tack Coat Materials between Polyurethane Mixture and Asphalt Mixture". The amount of tack coat material spread was 0.6 kg / m³. 2 The prepared specimens were immersed in water for 2 hours, and then placed in a refrigerator at -18°C for 16 hours. Subsequently, these specimens were immersed in a water bath at 60°C for 24 hours. Finally, the specimens were immersed in a water bath at 25°C for 2 hours. Interlaminar shear tests were then conducted on the treated specimens to obtain the interlaminar shear strength of different specimens. The calculation results are shown in Table 2. The interlaminar shear strength mainly depends on the hydrogen bonding between the polyurethane and the asphalt layer, the rigidity of the molecular chains, and the interfacial chemical bonding ability.

[0148] Table 2 Interlaminar shear strength of different specimens

[0149]

[0150] It can be seen that Examples 1 and 2 exhibit the best strength due to the synergistic effect of the entire system, forming a high-density hydrogen bond and a stable cross-linked network. Example 3 uses a low molecular weight diol with a high proportion of hard segments, resulting in enhanced rigidity but slightly lower toughness. Example 4 utilizes a trifunctional polyol to construct a highly cross-linked structure, significantly improving shear resistance. Example 5, due to its longer molecular chain and fewer cross-linking points, shows a slight decrease in strength.

[0151] Comparative Examples 1 and 2 lacked the active bonding mechanism of polyurethane, resulting in the lowest strength. Comparative Example 3 suffered gel demulsification due to R=1.1, leading to interfacial bonding failure. Comparative Example 4, using ordinary components, showed overall deterioration in bonding performance. Comparative Example 5 improved some water resistance through hydrolyzable isocyanate, but its effect on the polar groups of asphalt was limited. Comparative Example 6 relied on the stability of hydrolyzable polyol, but the lack of a strong hydrogen-bonding chain extender resulted in insufficient interfacial interaction. Comparative Example 7 enhanced physical adsorption through strong hydrogen bonding, but ordinary isocyanate limited chemical stability. Comparative Example 8 suffered from reduced crosslinking efficiency due to excessively long molecular chains, and Comparative Example 9 suffered from weakened cohesion due to excessively short chain segments, both affecting strength. Comparative Example 10 suffered from insufficient molecular weight due to R=0.9, resulting in decreased load-bearing capacity of the adhesive layer. Comparative Examples 11 and 12 lacked only a single high-performance component, resulting in strengths similar to but slightly lower than the examples. Comparative Example 13 suffered from weakened interfacial interaction because the ordinary chain extender could not provide sufficient hydrogen bonds.

[0152] The embodiments described above are some, but not all, of the embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A high performance tack coat material for polyurethane porous elastic mix pavements, characterized in that, Its raw material components include: functional polyurethane, asphalt, emulsifier and water; the functional polyurethane is obtained by reacting hydrolyzable isocyanate, hydrolyzable polyol and strong hydrogen bond chain extender; The weight ratio of the hydrolysis-resistant polyol, the strong hydrogen-bonding chain extender, and the hydrolysis-resistant isocyanate is 100:(6.5-17.4):(20-53.2). The ratio of the total molar number of isocyanate groups in the hydrolysis-resistant isocyanate to the total molar number of active hydrogens in the hydrolysis-resistant polyol and strong hydrogen bond chain extender is 0.95-0.

98. The hydrolysis-resistant isocyanate includes one or more of hexamethylene diisocyanate trimer, isophorone diisocyanate trimer, phenyl diisocyanate, and carbodiimide-modified diphenylmethane diisocyanate. The hydrolysis-resistant polyol has a functionality of 2-3 and a number-average molecular weight of 1000-4000; the hydrolysis-resistant polyol includes one or more of polypropylene glycol, polypropylene triol, and polytetrahydrofuran ether glycol. The strong hydrogen bond extender includes one or more of adipic acid dihydrazide and isophthalic acid dihydrazide.

2. The high performance bondline material of claim 1, wherein, The weight ratio of the functional polyurethane, asphalt, emulsifier and water is (3-6):100:(1-6):(25-100).

3. The high performance bondline material of claim 1, wherein, The hydrolysis-resistant polyols include polyoxypropylene triol with a number average molecular weight of 3000-4000 or polytetrahydrofuran ether diol with a number average molecular weight of 1000-2000.

4. A method of preparing a high performance adhesive interlayer as claimed in any one of claims 1 to 3, characterised in that, Includes the following steps: S1. Under inert gas protection, a hydrolyzable polyol and a strong hydrogen bond chain extender are heated and vacuum dehydrated; after cooling, a hydrolyzable isocyanate is added, and the reaction is maintained at the temperature to obtain a functional polyurethane. S2. Heat the asphalt, dissolve the emulsifier in water and heat it, add the hot emulsifier aqueous solution to the hot asphalt under high-speed shearing, and shear emulsify to obtain asphalt emulsion; S3. Add the functional polyurethane obtained in step S1 to the asphalt emulsion obtained in step S2, and stir continuously until it is mixed evenly to obtain the high-performance adhesive material.

5. Use of a high performance adhesive material according to any one of claims 1 to 3, characterized in that, The high-performance adhesive material is used to bond the upper layer of the polyurethane porous elastic mixture to the lower layer of the asphalt mixture.

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