1. The asphalt road interlayer adhesive is characterized by comprising the following raw materials in parts by weight: 100 parts of composite adhesive, 6-8 parts of cyclodextrin polyrotaxane and 2-4 parts of self-repairing microcapsules, wherein the composite adhesive is composed of epoxy resin adhesive and polyurethane adhesive.

2. The asphalt road interlayer adhesive as claimed in claim 1, wherein the weight ratio of the epoxy resin adhesive to the polyurethane adhesive is 1: 3-4.

3. The asphalt road interlayer adhesive as claimed in claim 1 or 2, wherein the content of isocyanate group in the composite adhesive is 14.5-16.5 wt%.

4. The asphalt road interlayer adhesive as claimed in any one of claims 1 to 3, wherein the viscosity of the composite adhesive is 3000-4500 MPa-s.

5. The asphalt road interlayer adhesive as claimed in any one of claims 1 to 4, wherein the cyclodextrin polyrotaxane is prepared by reacting beta-cyclodextrin, bis (2-aminopropyl) -terminated polypropylene glycol, aldehydized beta-cyclodextrin, and C60.

6. The asphalt road interlayer adhesive as claimed in any one of claims 1 to 5, wherein the shell material of the self-repairing microcapsule is urea-formaldehyde resin, and the core material is a repairing material.

7. The asphalt road interlayer adhesive as claimed in claim 6, wherein the self-repairing microcapsule is prepared by in-situ polymerization, wherein the weight ratio of the shell material to the core material is 1: 1.2-1.5.

8. A method for preparing the asphalt road interlayer adhesive according to any one of claims 1 to 7, comprising the steps of: and (3) uniformly mixing the polyurethane adhesive and the epoxy resin adhesive, adding the cyclodextrin polyrotaxane, uniformly mixing, and finally adding the self-repairing microcapsule, and uniformly mixing to obtain the self-repairing microcapsule adhesive.

9. The method for preparing the asphalt road interlayer adhesive according to claim 8, wherein the temperature for adding the cyclodextrin polyrotaxane is 40-60 ℃.

Background

Compared with cement concrete road surface, the asphalt road surface is smooth and has no joint, small vibration, low noise, fast traffic and simple maintenance, and is especially suitable for the construction of road surface. Accordingly, asphalt pavements are increasingly being used for newly repaired roads. In the process of renovating and rebuilding, a 'white to black' mode is also commonly adopted for a plurality of old cement concrete pavements, namely, an asphalt concrete surface course is additionally paved on the basis of treating the original cement concrete pavement.

With the application of the construction and maintenance process of changing the composite pavement from white to black, for example, pavements such as squares, airports, factories and districts are widely applied to the composite pavement. The composite pavement is usually an asphalt layer, and the design specifications for the composite pavement are carried out under the precondition that all the layers of the road are continuous, but in practice, the asphalt layer and the cement pavement layer are usually discontinuous, so that the performance of the pavement has larger deviation with the design estimation. The asphalt layer is additionally paved on the cement pavement, so that the interlayer shear stress and the surface layer stress are increased, and the mechanical analysis of the asphalt concrete surface layer by utilizing finite element software can obtain that the interlayer shear stress is just near the maximum of the shear stress, and the shear stress is increased along with the increase of the axle weight. When the surface layer is subjected to a large horizontal load, if the interlayer bonding force is small, fatigue cracks are easy to appear, and shearing damage is formed; in long and large longitudinal slopes or road sections of crossroads, factory areas and school areas, road surface diseases caused by large shear stress borne by the composite road surface structure and insufficient interlayer shear strength are correspondingly increased due to frequent braking and starting of vehicles. And groundwater gets into the pitch layer through the cement layer, and water gets into the pitch layer through the crack, causes the road surface to split easily, destroys the road surface. The current commonly used interlayer adhesive is mainly SBR modified asphalt, but the waterproof performance, the adhesive performance and the temperature stability are lower.

Disclosure of Invention

Based on the technical problems in the background art, the invention provides an asphalt road interlayer adhesive and a preparation method thereof.

The invention provides an asphalt road interlayer adhesive which comprises the following raw materials in parts by weight: 100 parts of composite adhesive, 6-8 parts of cyclodextrin polyrotaxane and 2-4 parts of self-repairing microcapsules, wherein the composite adhesive is composed of epoxy resin adhesive and polyurethane adhesive.

Preferably, the weight ratio of the epoxy resin adhesive to the polyurethane adhesive is 1: 3-4.

Preferably, the content of the isocyanate group in the composite adhesive is 14.5-16.5 wt%.

Preferably, the viscosity of the composite adhesive is 3000-.

The tensile strength of the composite adhesive is more than or equal to 10MPa, and the shear strength is more than or equal to 4 MPa.

The synthesis principle of the polyrotaxane is that linear molecules and cyclic molecules form pseudorotaxane, and then, two ends of the linear molecules are introduced with the sealing groups to assemble the rotaxane molecules.

The cyclodextrin polyrotaxane is an inclusion compound formed by utilizing the hydrophobic effect of a cyclodextrin (host) molecular cavity and a nonpolar or weak polar polymer molecular chain (object) through the self-assembly effect; in order to avoid that cyclodextrin cannot be separated from the guest molecule chain, modification treatment of the guest molecule, including capping of the terminal group, etc., is required to form a so-called bulky group "plug", and to prevent the cyclodextrin from falling off by steric hindrance.

The molecular chain of the polymer can be polyethylene glycol, polypropylene glycol, polyethyleneimine-b-polyethylene glycol-b-polyethyleneimine copolymer (PEI-b-PEG-b-PEI), polypropylene glycol-bis [3,4, 5-tri (propargyloxy) benzamide ] and the like, and the end-capping agent can be 2, 4-dinitrofluorobenzene, aldehyde beta-cyclodextrin, C60, 9-anthracenal, 2-azidoethanol and the like.

Preferably, the cyclodextrin polyrotaxane is prepared by reacting beta-cyclodextrin, bis (2-aminopropyl) terminated polypropylene glycol, aldehyde-modified beta-cyclodextrin and C60.

The preparation of the above-mentioned cyclodextrin polyrotaxanes is a method which is conventional in the art and can be obtained by the method described in the literature Liu Y, Yang Y W, Chen Y, Zou HX, Polyrotaxane with cyclodextrines as Stoppers and Its Association Behavior [ J ]. Macromolecules,2005,38(13): 5838-.

Preferably, the shell material of the self-repairing microcapsule is urea-formaldehyde resin, and the core material is a repairing material.

Preferably, the self-repairing microcapsule is prepared by an in-situ polymerization method, wherein the weight ratio of the shell material to the core material is 1: 1.2-1.5.

The in situ polymerization process is a common method for preparing microcapsules.

The repairing material can be oily asphalt repairing agent, 5-ethylidene norbornene, styryl, 1-n-butyl glycidyl ether and the like.

The shell material can be melamine formaldehyde resin, methanol modified melamine formaldehyde resin, urea formaldehyde resin, methylated hexamethylol melamine resin, sodium alginate, chitosan, gelatin, dextrin, carboxymethyl cellulose, polylactic acid, polypropylene, polyvinyl alcohol, etc.

The invention also provides a preparation method of the asphalt road interlayer adhesive, which comprises the following steps: and (3) uniformly mixing the polyurethane adhesive and the epoxy resin adhesive, adding the cyclodextrin polyrotaxane, uniformly mixing, and finally adding the self-repairing microcapsule, and uniformly mixing to obtain the self-repairing microcapsule adhesive.

Preferably, the temperature for adding cyclodextrin polyrotaxane and mixing is 40-60 ℃.

Has the advantages that:

1. the polyurethane adhesive and the epoxy resin adhesive are matched with each other in a proper proportion to obtain the composite adhesive with specific viscosity and isocyanate group content, so that the adhesive force between the composite adhesive and cement-based pavements and asphalt pavements can be improved; the polyurethane adhesive with a proper amount is not sensitive to temperature, so that the problems that the shear strength and the drawing strength of the adhesive are greatly reduced at high temperature and the adhesive force is reduced are solved; the proper amount of epoxy resin can further improve the waterproof performance of the asphalt waterproof coating, and prevent the damage of underground water to an asphalt layer;

2. cyclodextrin Polyrotaxane Cyclodextrin having a plurality of hydroxyl groups which can bond to isocyanate groups in the polyurethane to thereby link to the polyurethane backbone; when the polyurethane is extruded or pulled by external force, the guest molecular chain in the cyclodextrin polyrotaxane is pulled, the cyclodextrin slides along the guest molecular chain, the external force is relieved, and the cyclodextrin is completely and directly acted on the polyurethane main chain to play a role in buffering the external force, so that the shearing strength and the bonding strength of the polyurethane are improved;

3. under the action of external force, when micro cracks appear on the cement pavement or the asphalt pavement, the self-repairing microcapsules are extruded and broken by the external force, and the core material repairing material flows out to repair the micro cracks in time; when microcracks are generated, an object molecular chain in the cyclodextrin polyrotaxane is pulled and deformed by external force, then the object molecular chain is gradually recovered to the original relaxation state, the cyclodextrin slides along the object molecular chain and drives the polyurethane main adhesive to be tightened to the cracks, and therefore the repair of the cracks is further promoted; according to the invention, through the mutual matching of the substances, the adhesive has good adhesion, shear strength and waterproof performance, and has self-repairing performance.

Detailed Description

The technical solution of the present invention will be described in detail below with reference to specific examples.

Example 1

The preparation method of the asphalt road interlayer adhesive comprises the following steps:

cyclodextrin polyrotaxanes were prepared by the method described in Liu Y, Yang Y W, Chen Y, Zou HX. Polyrotaxane with cyclodextrines as Stoppers and Its Association Behavior [ J ]. Macromolecules,2005,38(13): 5838-;

adding an oily asphalt repairing agent into a styrene maleic anhydride (surfactant) aqueous solution, dispersing and emulsifying at a high speed for 10min, and uniformly mixing to obtain an emulsion; slowly dropwise adding a methylated hexamethylol melamine prepolymer solution into the emulsion, uniformly stirring at the speed of 500r/min, heating to 65 ℃ after dropwise adding, adjusting the pH to 5 by using an acetic acid aqueous solution, heating to 80 ℃, keeping the temperature, stirring, reacting for 2 hours, cooling to room temperature, filtering, washing and drying to obtain a self-repairing microcapsule, wherein the weight ratio of the methylated hexamethylol melamine prepolymer to the oily asphalt repairing agent is 1: 1.2;

shearing and uniformly mixing 16g of polyurethane adhesive and 4g of epoxy resin (E51) adhesive at room temperature to obtain a composite adhesive with the content of isocyanate group being 14.5-16.5 wt% and the viscosity being 3000-4500 MPa.s, then adding 1.6g of cyclodextrin polyrotaxane, shearing and uniformly mixing at 40 ℃, and finally adding 0.8g of self-repairing microcapsule, shearing and uniformly mixing at room temperature to obtain the polyurethane adhesive.

Example 2

The preparation method of the asphalt road interlayer adhesive comprises the following steps:

cyclodextrin polyrotaxanes were prepared by the method described in Liu Y, Yang Y W, Chen Y, Zou HX. Polyrotaxane with cyclodextrines as Stoppers and Its Association Behavior [ J ]. Macromolecules,2005,38(13): 5838-;

adding an oily asphalt repairing agent into a styrene maleic anhydride (surfactant) aqueous solution, dispersing and emulsifying at a high speed for 10min, and uniformly mixing to obtain an emulsion; slowly dropwise adding a methylated hexamethylol melamine prepolymer solution into the emulsion, uniformly stirring at the speed of 500r/min, heating to 65 ℃ after dropwise adding, adjusting the pH to 5 by using an acetic acid aqueous solution, heating to 80 ℃, keeping the temperature, stirring, reacting for 2 hours, cooling to room temperature, filtering, washing and drying to obtain a self-repairing microcapsule, wherein the weight ratio of the methylated hexamethylol melamine prepolymer to the oily asphalt repairing agent is 1: 1.5;

shearing and uniformly mixing 15g of polyurethane adhesive and 5g of epoxy resin (E51) adhesive at room temperature to obtain a composite adhesive with the content of isocyanate group being 14.5-16.5 wt% and the viscosity being 3000-4500 MPa.s, then adding 1.2g of cyclodextrin polyrotaxane, shearing and uniformly mixing at 60 ℃, and finally adding 0.4g of self-repairing microcapsule, shearing and uniformly mixing at room temperature to obtain the polyurethane adhesive.

Example 3

The preparation method of the asphalt road interlayer adhesive comprises the following steps:

cyclodextrin polyrotaxanes were prepared by the method described in Liu Y, Yang Y W, Chen Y, Zou HX. Polyrotaxane with cyclodextrines as Stoppers and Its Association Behavior [ J ]. Macromolecules,2005,38(13): 5838-;

adding an oily asphalt repairing agent into a styrene maleic anhydride (surfactant) aqueous solution, dispersing and emulsifying at a high speed for 10min, and uniformly mixing to obtain an emulsion; slowly dropwise adding a methylated hexamethylol melamine prepolymer solution into the emulsion, uniformly stirring at the speed of 500r/min, heating to 65 ℃ after dropwise adding, adjusting the pH to 5 by using an acetic acid aqueous solution, heating to 80 ℃, keeping the temperature, stirring, reacting for 2 hours, cooling to room temperature, filtering, washing and drying to obtain a self-repairing microcapsule, wherein the weight ratio of the methylated hexamethylol melamine prepolymer to the oily asphalt repairing agent is 1: 1.3;

shearing and uniformly mixing 15.5g of polyurethane adhesive and 4.5g of epoxy resin (E51) adhesive at room temperature to obtain a composite adhesive with the isocyanate group content of 14.5-16.5 wt% and the viscosity of 3000-4500 MPa.s, then adding 1.4g of cyclodextrin polyrotaxane, shearing and uniformly mixing at 50 ℃, and finally adding 0.6g of self-repairing microcapsule, shearing and uniformly mixing at room temperature to obtain the polyurethane adhesive.

Comparative example 1

SBR modified asphalt.

Comparative example 2

The procedure is as in example 3 except that the cyclodextrin polyrotaxane is not included.

Comparative example 3

The procedure is as in example 3 except that no epoxy resin adhesive is contained.

Comparative example 4

The procedure is as in example 3 except that the self-repairing microcapsules are not contained.

Experiment of

The binders prepared in examples 1 to 3 and the binders prepared in comparative examples 1 to 4 were applied to the base surfaces of the cement concrete samples in the same manner in an amount of 0.5kg/m²(ii) a Then paving an asphalt surface layer to obtain a composite sample (the diameter is 100mm, and the height is 200 mm). The composite test piece was then fixed to a universal testing machine, the computer program was operated, and the 45 ° skew shear test and pull test loading was performed at a rate of 10mm/min until the test piece was destroyed (10 parallel samples per group, the results averaged), and the results are shown in table 1.

TABLE 1 test results

As can be seen from the above table: the invention has good shear strength and adhesive property and good temperature stability.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.