Emulsified asphalt with high stability and high internal phase and preparation method thereof

Abstract

The invention relates to the technical field of road emulsified asphalt, in particular to super-stability high-internal-phase emulsified asphalt and a preparation method thereof.The super-stability high-internal-phase emulsified asphalt is prepared from, by weight, 80-90 parts of matrix asphalt, 20-30 parts of a quick-breaking and quick-setting emulsifier, 20-30 parts of a slow-breaking and quick-setting emulsifier, 20-30 parts of hydrochloric acid, 20-30 parts of hydrophilic and oleophylic modified nano SiO2 particles and 20-30 parts of deionized water. According to the emulsified asphalt demulsifying agent, the stability of the internal structure of the emulsified asphalt can be greatly improved, and the demulsification time of the emulsified asphalt can be prolonged. And the preparation cost is low, and the improvement effect on the cold-mixed asphalt mixture is good.

Description

Technical Field

[0001] The invention relates to the technical field of road emulsified asphalt, and specifically relates to ultra-stable high-internal-phase emulsified asphalt and a preparation method thereof. Background Art

[0002] With the continuous development of the economy, the demand for asphalt materials on high-grade highways continues to increase. Most of the asphalt mixtures on highways are still paved by hot mixing and hot paving, which will cause a large amount of greenhouse gas emissions and energy waste. The cold mixing and cold paving mixture construction technology can be carried out at room temperature during construction, without greenhouse gas emissions, saving a lot of energy and reducing construction costs; the strength of the mixture will gradually form under the long-term action of traffic load and external environment, reducing the impact on the external environment. However, due to the late and insufficient research on emulsified asphalt cold mix in my country, it is currently mainly used in emergency repairs of road potholes, preventive maintenance micro-surfacing and slurry sealing in China, and is rarely used for new road paving. This is mainly because the strength of traditional emulsified asphalt mixtures will gradually increase with the evaporation of water, and water will reduce the adhesion of emulsified asphalt. The presence of water will lead to a decrease in the bonding ability of asphalt and aggregates and the cohesion of asphalt. After the evaporation of water, voids will form inside the mixture, resulting in low strength and poor water stability of the emulsified asphalt mixture, which seriously affects its further application. Summary of the invention

[0003] In view of the deficiencies in the prior art, the purpose of the present invention is to provide an ultra-stable high-internal phase emulsified asphalt and a preparation method thereof, so as to solve the defects of traditional emulsified asphalt due to its high water content, resulting in a large void ratio, resulting in poor overall strength and water stability of the mixture. As an emulsified asphalt with low water content and high asphalt content, the present invention has significant advantages. It not only meets the advantages of low viscosity and easy mixing of traditional emulsified asphalt, but also meets the advantages of low water content and reduction of excessive void ratio caused by water evaporation, so that cold-mix asphalt mixture can be more widely used.

[0004] To achieve the above object, the present invention provides the following technical solution: an ultra-stable high internal phase emulsified asphalt, comprising base asphalt, a fast-cracking and fast-setting emulsifier, a slow-cracking and fast-setting emulsifier, hydrochloric acid, a hydrophilic and lipophilic modified nano-SiO 2 The particles and deionized water are composed of the following proportions: 80-90 parts of base asphalt, 1 part of fast-cracking and fast-setting emulsifier, 3 parts of slow cracking and fast setting emulsifier, Hydrophilic and lipophilic modified nano-SiO 2 0.5 parts of granules, 5.5-15.5 parts of deionized water.

[0005] In some of the embodiments, the base asphalt is 90# asphalt.

[0006] In some of the embodiments, the fast-cracking and fast-setting emulsifier is a 802-K fast-cracking and fast-setting emulsifier.

[0007] In some of the embodiments, the slow-cracking, fast-setting emulsifier is a 803-K slow-cracking, fast-setting emulsifier.

[0008] In some embodiments, the hydrophilic and lipophilic modified nano-SiO 2 The particles are hydrophilic and lipophilic 20nm modified nano-SiO 2 Particles.

[0009] In some of the embodiments, the quick-cracking and quick-setting emulsifier, the slow-cracking and quick-setting emulsifier, hydrochloric acid and deionized water are mixed to form a soap solution.

[0010] In some of the embodiments, the high internal phase emulsified asphalt is an emulsion with an asphalt volume fraction ≥ 74%.

[0011] To achieve the above object, the present invention also provides the following technical solution: a method for preparing ultra-stable high internal phase emulsified asphalt, characterized in that the steps are: (1) heating the base asphalt; (2) taking a preset number of portions of a quick-cracking quick-setting emulsifier, a slow-cracking quick-setting emulsifier and deionized water, mixing them, and adding hydrochloric acid to adjust the pH to prepare a soap solution; (3) Add the hydrophilic and lipophilic modified nano-SiO2 particles into the prepared soap solution and stir; (4) Pour the heated asphalt into a container, place it in an oil bath for heat preservation, and turn on the high-speed shearing machine for shearing at a shear rate of 5000~6000rpm; (5) Add all the prepared soap solution into the container containing asphalt and shear it for 3 to 5 minutes.

[0012] In some embodiments, the heating temperature in step (1) is 120°C.

[0013] Compared with the prior art, the invention has the following beneficial effects: the preparation method of the ultra-stable high internal phase emulsion can significantly reduce the water content of the emulsified asphalt and improve the water stability and strength of the cold-mixed asphalt mixture; the preparation method of the Pickering emulsion can significantly improve the internal structural stability of the emulsified asphalt and extend the emulsification time of the emulsified asphalt. The preparation cost is low, the improvement effect on the cold-mixed asphalt mixture is good, and it is an environmentally friendly and stable asphalt.

[0014] Details of one or more embodiments of the present application are presented in the following drawings and descriptions to make other features, purposes and advantages of the present application more concise and easy to understand. The present application is fully described and understood through the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a preparation flow chart of the present invention. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] See also Figure 1 The present invention provides a technical solution: a super-stable high internal phase emulsified asphalt, comprising base asphalt, a fast-cracking and fast-setting emulsifier, a slow-cracking and fast-setting emulsifier, hydrochloric acid, a hydrophilic and lipophilic modified nano-SiO 2 The particles and deionized water are composed of the following proportions: 80-90 parts of base asphalt, 1 part of fast-cracking and fast-setting emulsifier, 3 parts of slow cracking and fast setting emulsifier, Hydrophilic and lipophilic modified nano-SiO 2 0.5 parts of granules, 5.5-15.5 parts of deionized water.

[0018] The matrix asphalt is 90# asphalt.

[0019] The fast-cracking and fast-setting emulsifier is a 802-K fast-cracking and fast-setting emulsifier.

[0020] The slow-cracking and fast-setting emulsifier is a 803-K slow-cracking and fast-setting emulsifier.

[0021] The above-mentioned 802-K fast-cracking and fast-setting emulsifier and 803-K slow-cracking and fast-setting emulsifier are produced by Tianjin Kangzewei Company.

[0022] The hydrophilic and lipophilic modified nano-SiO 2 The particles are hydrophilic and lipophilic 20nm modified nano-SiO 2 Particles, nano-SiO2 particles are produced by Shanghai Yaoyi Alloy Materials Co., Ltd.

[0023] The quick-cracking and quick-setting emulsifier, the slow-cracking and quick-setting emulsifier, hydrochloric acid and deionized water are mixed to form a soap solution.

[0024] The high internal phase emulsified asphalt is an emulsion with an asphalt volume fraction of ≥74%.

[0025] A method for preparing ultra-stable high internal phase emulsified asphalt, comprising the following steps: (1) heating the base asphalt; (2) taking a preset number of portions of a quick-cracking quick-setting emulsifier, a slow-cracking quick-setting emulsifier and deionized water, mixing them, and adding hydrochloric acid to adjust the pH to prepare a soap solution; (3) Add the hydrophilic and lipophilic modified nano-SiO2 particles into the prepared soap solution and stir; (4) Pour the heated asphalt into a container, place it in an oil bath for heat preservation, and turn on the high-speed shearing machine for shearing at a shear rate of 5000~6000rpm; (5) Add all the prepared soap solution into the container containing asphalt and shear it for 3 to 5 minutes.

[0026] The heating temperature in step (1) is 120°C.

[0027] Through this technical solution, Example

[0028] Heat 75% asphalt content to 120℃, take 3% mass fraction of fast-cracking fast-setting emulsifier and slow-cracking fast-setting emulsifier and deionized water, mix them in a certain proportion, add hydrochloric acid to adjust the pH, prepare soap solution, add 1% mass fraction of hydrophilic and lipophilic modified nano-SiO2 particles into the prepared soap solution, stir; turn on the high-speed shearing machine for shearing, the shear rate is 5000rpm; add all the prepared soap solution into the container containing asphalt, shear, and the shearing time is 3min. The ultra-stable high internal phase emulsified asphalt A1 is obtained. Example

[0029] Heat 80% asphalt content to 120℃, take 4% of fast-cracking, fast-setting emulsifier, slow-cracking, fast-setting emulsifier and deionized water, mix them in a certain proportion, add hydrochloric acid to adjust the pH, prepare soap solution, add 1% of hydrophilic and lipophilic modified nano-SiO2 particles to the prepared soap solution, stir; turn on the high-speed shearing machine for shearing, the shear rate is 5500rpm; add all the prepared soap solution into the container containing asphalt, shear, and the shearing time is 4min. The ultra-stable high internal phase emulsified asphalt A2 is obtained. Example

[0030] Heat 85% asphalt content to 120℃, take 5% mass fraction of fast-cracking fast-setting emulsifier and slow-cracking fast-setting emulsifier and deionized water, mix them in a certain proportion, add hydrochloric acid to adjust the pH, prepare soap solution, add 1% mass fraction of hydrophilic and lipophilic modified nano-SiO2 particles into the prepared soap solution, stir; turn on the high-speed shearing machine for shearing, the shear rate is 6000rpm; add all the prepared soap solution into the container containing asphalt, shear, and the shearing time is 5min. The ultra-stable high internal phase emulsified asphalt A3 is obtained.

[0031] Comparative Example 1 The material preparation method and formula are the same as those in Example 2, with the only difference being that the emulsifier content is 2%, thereby obtaining ultra-stable high internal phase emulsified asphalt A4.

[0032] Comparative Example 2 The material preparation method and formulation are the same as those in Example 2, with the only difference being that the stirring time is 2 minutes, and thus ultra-stable high internal phase emulsified asphalt A5 is obtained.

[0033] Comparative Example 3 The material preparation method and formula are the same as those in Example 2, the only difference being that no modified nano-SiO2 particle content is added, thereby obtaining ultra-stable high internal phase emulsified asphalt A6.

[0034] Table 1 Composition (mass fraction) of ultra-stable high internal phase asphalt materials

[0035] Table 2 Technical indicators of ultra-stable high internal phase emulsified asphalt materials

[0036] As can be seen from Table 2, the emulsification effect of the present invention is relatively good under different asphalt contents. Through comparative examples 1, 2, and 3, we can conclude that when the emulsifier content is less than 3% and the shear time is short, the asphalt is not completely emulsified, and the modified hydrophilic and lipophilic SiO2 can slightly increase the viscosity of the ultra-stable high internal phase emulsified asphalt, but can significantly extend the storage time of the ultra-stable high internal phase emulsified asphalt.

[0037] In summary, ultra-stable high internal phase emulsified asphalt can be prepared by adding a certain amount of fast-cracking and fast-setting emulsifiers and slow-cracking and fast-setting emulsifiers under a certain shear time and shear rate. Adding modified hydrophilic and lipophilic SiO2 particles can greatly increase the storage time. The present invention has good emulsification, storage and mixing properties under the corresponding process preparation.

[0038] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

[0039] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An ultra-stable high internal phase emulsified asphalt, characterized in that: It is composed of base asphalt, fast-cracking and fast-setting emulsifier, slow-cracking and fast-setting emulsifier, hydrochloric acid, hydrophilic and lipophilic modified nano-SiO2 particles and deionized water, wherein the proportion of each component material is as follows: 80-90 parts of base asphalt, 1 part of fast-cracking and fast-setting emulsifier, 3 parts of slow cracking and fast setting emulsifier, 0.5 parts of hydrophilic and lipophilic modified nano-SiO2 particles, 5.5-15.5 parts of deionized water.

2. The ultra-stable high internal phase emulsified asphalt according to claim 1, characterized in that: The matrix asphalt is 90# asphalt.

3. The ultra-stable high internal phase emulsified asphalt according to claim 1, characterized in that: The fast-cracking and fast-setting emulsifier is a 802-K fast-cracking and fast-setting emulsifier.

4. The ultra-stable high internal phase emulsified asphalt according to claim 1, characterized in that: The slow-cracking and fast-setting emulsifier is a 803-K slow-cracking and fast-setting emulsifier.

5. The ultra-stable high internal phase emulsified asphalt according to claim 1, characterized in that: The hydrophilic-lipophilic modified nano-SiO2 particles are hydrophilic-lipophilic modified nano-SiO2 particles with a size of 20 nm.

6. The ultra-stable high internal phase emulsified asphalt according to claim 1, characterized in that: The quick-cracking and quick-setting emulsifier, the slow-cracking and quick-setting emulsifier, hydrochloric acid and deionized water are mixed to form a soap solution.

7. The ultra-stable high internal phase emulsified asphalt according to claim 1, characterized in that: The high internal phase emulsified asphalt is an emulsion with an asphalt volume fraction of ≥74%.

8. A method for preparing an ultra-stable high internal phase emulsified asphalt according to any one of claims 1 to 7, characterized in that: The steps are: (1) heating the base asphalt; (2) taking a preset number of portions of a quick-cracking quick-setting emulsifier, a slow-cracking quick-setting emulsifier and deionized water, mixing them, and adding hydrochloric acid to adjust the pH to prepare a soap solution; (3) Add the hydrophilic and lipophilic modified nano-SiO2 particles into the prepared soap solution and stir; (4) Pour the heated asphalt into a container, place it in an oil bath for heat preservation, and turn on the high-speed shearing machine for shearing at a shear rate of 5000~6000rpm; (5) Add all the prepared soap solution into the container containing asphalt and shear it for 3 to 5 minutes.

9. The method for preparing an ultra-stable high internal phase emulsified asphalt according to claim 8, characterized in that: The heating temperature in step (1) is 120°C.

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