UV-reinforced polyvinyl butyral modified asphalt and preparation method thereof

Abstract

The invention provides UV (ultraviolet) reinforced polyvinyl butyral modified asphalt and a preparation method thereof. The modified asphalt is based on matrix asphalt, polyvinyl butyral, a photoinitiator and a cross-linking aid are added, and uniform dispersion and cross-linking reaction of polyvinyl butyral in an asphalt system are promoted through UV illumination, so that the ultraviolet aging resistance, bonding strength and weather resistance of the asphalt are improved. The preparation method comprises the following steps: heating the matrix asphalt to 140-190 DEG C, adding the polyvinyl butyral, shearing and stirring, then adding the photoinitiator and the crosslinking aid, and continuously stirring under the condition of UV illumination to form a uniform modified asphalt system. According to the method, the aging resistance, high-temperature stability and low-temperature crack resistance of the modified asphalt can be remarkably improved, and the modified asphalt is suitable for the fields of road paving, bridge waterproofing and other high-durability engineering and has a good industrial application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of road engineering materials and waterproof materials, and in particular to UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof. Background Art

[0002] Asphalt is widely used in engineering fields such as road paving, bridge waterproofing and building sealing due to its excellent adhesion and waterproof properties. However, traditional asphalt will age due to ultraviolet (UV) radiation, oxidation, high temperature and humid environment during long-term use, resulting in problems such as lower softening point, cracking, and decreased adhesion strength, which seriously affects the service life of roads and waterproof layers. Therefore, improving the anti-aging ability, weather resistance and adhesion strength of asphalt is one of the important directions of current research on road engineering and waterproof materials.

[0003] Polyvinyl Butyral (PVB) is a polymer material with excellent weather resistance, oxidation resistance, flexibility and adhesion. It has been widely used in laminated glass, composite materials and coatings. Introducing PVB as a modifier into asphalt is expected to improve the high temperature stability, low temperature crack resistance and aging resistance of asphalt. However, the dispersibility and compatibility of PVB in the asphalt system are poor, which affects the modification effect. Therefore, there is an urgent need for an efficient method to improve the stability and durability of PVB modified asphalt.

[0004] Ultraviolet (UV) strengthening technology is an efficient modification method that has been applied in the cross-linking and weather resistance improvement of polymer materials. Through the synergistic effect of photoinitiators (such as benzophenone, dimethyl benzoate, etc.) and cross-linking aids (such as benzoyl peroxide, bismaleimide, etc.), the cross-linking reaction between PVB and asphalt molecules can be triggered under UV light to form a stable network structure, thereby improving the aging resistance, bonding strength and long-term performance of the modified asphalt. In addition, the reasonable regulation of UV irradiation wavelength and irradiation intensity can further optimize the cross-linking reaction and improve the modification effect.

[0005] Based on the above background, the present invention provides a UV-strengthened PVB modified asphalt and a preparation method thereof, wherein the organic compounding of base asphalt, PVB resin, photoinitiator and cross-linking aid is performed, and the PVB is strengthened by UV light, so that the PVB forms a uniform and stable cross-linking structure in the asphalt system, thereby improving the asphalt's anti-ultraviolet aging ability, weather resistance and bonding strength. The modified asphalt prepared by the method can be widely used in road paving, bridge waterproofing, tunnel lining and other high-durability engineering fields, and has important engineering application value and promotion prospects. Summary of the invention

[0006] The present invention provides a UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof, aiming to improve the UV aging resistance, bonding strength and weather resistance of asphalt. By introducing a photoinitiator and a crosslinking aid into the polyvinyl butyral (PVB) modified asphalt system, and combining ultraviolet (UV) irradiation technology, the uniform dispersion and crosslinking reaction of PVB in asphalt are promoted, thereby forming a stable modified asphalt system, overcoming the problems of poor dispersibility of PVB in asphalt and limited modification effect in the prior art.

[0007] The technical solution of the present invention: a UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof, characterized in that it comprises the following raw materials in parts by weight: 100 parts of base asphalt, 5-15 parts of polyvinyl butyral, 0.5-2.5 parts of photoinitiator, and 0.1-1.5 parts of cross-linking aid.

[0008] The aforementioned UV-strengthened polyvinyl butyral modified asphalt and preparation method thereof are characterized in that the base asphalt is at least one of 70# asphalt or 90# asphalt.

[0009] The aforementioned UV-strengthened polyvinyl butyral modified asphalt and preparation method thereof are characterized in that the photoinitiator is one or more of benzophenone, benzoin dimethyl ether and 2,4,6 (trimethylbenzoyl) diphenyl phosphine oxide.

[0010] The aforementioned UV-strengthened polyvinyl butyral modified asphalt and preparation method thereof are characterized in that the cross-linking aid is one or more of benzoyl peroxide, di-tert-butyl peroxide, p-benzoylquinone dioxime and bismaleimide.

[0011] A UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof, characterized in that the steps include: (1) Heat the base asphalt at 140-190°C to completely melt it; (2) Add polyvinyl butyral to the molten asphalt under stirring conditions, and continue shearing and stirring for 30-60 minutes to fully disperse it; (3) Add photoinitiator and crosslinking aid, maintain temperature and stir for 10 minutes, then continue stirring under UV light for 20-50 minutes to form a uniform modified asphalt system; (4) Cooling to room temperature to obtain UV-strengthened polyvinyl butyral modified asphalt.

[0012] The aforementioned UV-strengthened polyvinyl butyral modified asphalt and preparation method thereof are characterized in that the wavelength range of the UV light is 260-380 nm and the irradiation intensity is 20-40 mW / cm².

[0013] The beneficial effects of the present invention are as follows: (1) Significantly improve the UV aging resistance: UV light combined with light-induced cross-linking technology is used to form a stable network structure of PVB in asphalt, which improves the UV aging resistance of asphalt, reduces the performance degradation caused by long-term exposure to sunlight, and effectively extends the service life of roads and waterproof materials. (2) Enhanced bonding strength and durability: The introduction of PVB improves the polarity of asphalt, enhances its adhesion to mineral aggregates or base materials, reduces the risk of peeling, and improves the stability and durability of engineering structures. (3) Optimize high temperature stability and low temperature crack resistance: UV-strengthened PVB-modified asphalt can maintain good rheological properties at high temperatures, reduce the risk of softening, and improve flexibility at low temperatures, reducing the risk of cracks caused by temperature changes. (4) Improve the controllability and applicability of the preparation process: The preparation method of the present invention combines temperature-controlled stirring with UV irradiation, has a simple process and low energy consumption, is suitable for large-scale industrial production, and can be applied to road paving, waterproofing engineering and other fields, and has good promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the preparation process of the polyvinyl butyral modified asphalt of the present invention.

[0015] Figure 2 It is a performance comparison diagram of the embodiment and the comparative example. DETAILED DESCRIPTION

[0016] The effects and results of the method of the present invention are further described below with reference to the embodiments, but are not limited to the following embodiments.

[0017] Example: Take 100 g of 70# asphalt and heat it at 150°C until it is completely melted. Under stirring conditions, add 10 g of polyvinyl butyral to the molten asphalt, and continue shearing and stirring for 30 minutes to fully disperse it; add 1 g of benzophenone and 0.5 g of bismaleimide, maintain the temperature and stir for 10 minutes, then continue stirring for 30 minutes under UV light irradiation with a wavelength of 360 nm and an irradiation intensity of 30mW / cm² to form a uniform modified asphalt system, and then cool to room temperature to obtain UV-strengthened polyvinyl butyral modified asphalt.

[0018] Comparative Example: The steps were the same as those described in the example, except that the amount of polyvinyl butyral added was changed from 10 g to 0 g, and the sample was not irradiated with UV light.

[0019] The schematic diagram of the preparation process of the PVB modified asphalt of the present invention is as follows Figure 1 As shown. Softening point, penetration and ductility are the three key indicators for measuring asphalt performance. The test results of the examples and comparative examples are shown in Figure 2 As shown. Figure 2It can be seen that the present invention significantly improves the softening point of asphalt, enhances its adhesion and plasticity in high temperature environments, and thus improves the anti-rutting performance. The reduction in needle penetration shows that under the action of UV strengthening, PVB and asphalt undergo synergistic cross-linking to form a denser network structure, which increases the viscosity of asphalt and reduces the impact of temperature fluctuations on rheological properties. The ductility test results show that UV-strengthened PVB effectively improves the ductility of asphalt, improves its deformation resistance, and helps to enhance the overall durability and crack resistance of the material. In addition, the cross-linking of PVB and asphalt under UV strengthening can effectively improve the anti-aging properties of asphalt, reduce the impact of ultraviolet rays and oxidation on asphalt performance, slow down its aging rate, and thus extend the service life of asphalt materials.

[0020] It can be seen from the above examples that the UV-strengthened polyvinyl butyral modified asphalt prepared by the present invention has excellent performance in high temperature stability, adhesion, deformation resistance and anti-aging performance, which significantly improves the overall performance of the modified asphalt. Compared with conventional technologies, the content of the present invention has significant technical progress, reflecting high innovation and engineering application value.

Claims

1. A UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof, characterized in that: The invention comprises the following raw materials in parts by weight: 100 parts of base asphalt, 5-15 parts of polyvinyl butyral, 0.5-2.5 parts of photoinitiator and 0.1-1.5 parts of cross-linking auxiliary agent.

2. A UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof according to claim 1, characterized in that: The matrix asphalt is at least one of 70# asphalt and 90# asphalt.

3. A UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof according to claim 1, characterized in that: The photoinitiator is one or more of benzophenone, benzoin dimethyl ether and 2,4,6 (trimethylbenzoyl) diphenyl phosphine oxide.

4. The UV-strengthened polyvinyl butyral modified asphalt and the preparation method thereof according to claim 1, characterized in that: The cross-linking aid is one or more of benzoyl peroxide, di-tert-butyl peroxide, p-benzoylquinone dioxime and bismaleimide.

5. A UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof, characterized in that: The following steps are involved: S1. Heat the base asphalt at 140-190°C to completely melt it; S2. Add polyvinyl butyral to the molten asphalt under stirring conditions, and continue shearing and stirring for 30-60 minutes to fully disperse it; S3, adding photoinitiator and crosslinking aid, maintaining temperature and stirring for 10 minutes, and then continuing stirring for 20-50 minutes under UV light to form a uniform modified asphalt system; S4. Cooling to room temperature to obtain UV-strengthened polyvinyl butyral modified asphalt.

6. A UV-strengthened polyvinyl butyral modified asphalt and a preparation method thereof according to claim 5, characterized in that: The wavelength of the UV light is in the range of 260-380 nm, and the irradiation intensity is 20-40 mW / cm².

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