WO2011057455A1

WO2011057455A1 - High-strength structural asphalt material

Info

Publication number: WO2011057455A1
Application number: PCT/CN2009/074951
Authority: WO
Inventors: 周德洪; 汪红兵; 陶红
Original assignee: 江苏宝利沥青股份有限公司
Priority date: 2009-11-16
Filing date: 2009-11-16
Publication date: 2011-05-19

Abstract

A high-strength structural asphalt material comprises, by weight, 25-30 parts of new polyolefin material, 57-67 parts of old polyolefin material, 3-5 parts of inorganic filler, 0.8-1 parts of ultrafine carbon black particles, 2-4.5 parts of organic acid anhydride and 0.1-0.15 parts of antioxidant. A method for producing the high-strength structural asphalt material is also provided. The high-strength structural asphalt material has low production cost and good dispersibility, and can considerably increase the modulus of asphalt mixture.

Description

High-strength structural asphalt material and preparation method thereof

The invention relates to an additive material for asphalt mixture (for road paving) and a preparation method thereof, in particular to a high-strength structural asphalt material capable of significantly improving the modulus of "asphalt mixture" and having high dispersion property and preparation thereof method. Background technique

With the continuous increase of road traffic volume in China, especially the increase of heavy-duty vehicles and the use of high-pressure tires, the channelization of traffic flow and the persistent high temperature weather in summer. Road ruts have become the main form of early damage to road pavement. The rut not only deforms the road surface, but also degrades the flatness, and also seriously jeopardizes the safety of driving. Because the high-speed vehicles encounter water in the stern pit, drift will occur, posing a danger to driving.

Studies at home and abroad have shown that the higher the modulus of the asphalt mixture, the stronger the anti-rutting ability of the paved asphalt pavement. Therefore, improving the modulus of asphalt mixture is an important method to solve the problem of asphalt pavement rutting. There are various ways to increase the modulus of the asphalt mixture. In recent years, the direct addition of an additive to an asphalt mixture to increase the modulus of the asphalt mixture has received widespread attention.

It is known that conventional asphalt mixture additives for improving the modulus of asphalt mixture at home and abroad, such as French PR materials and German DUROFLB materials, are physically compounded by polyolefins and other high polymers. The conventional compound additive improves the modulus of the asphalt mixture by the following four aspects, thereby improving the rutting resistance of the asphalt pavement and improving the water damage resistance and the low temperature crack resistance.

1. The additive of the mixture is added to the stone and dry mixed with the stone at 180 ° C. Some of the additives melted on the surface of the stone have a bonding effect on the stone.

2. The mixture additive and the stone material are dry-mixed and then added to the asphalt for wet mixing. During the wet mixing process, some additives are swollen in the asphalt, which improves the softening point of the asphalt, increases the viscosity of the asphalt, and lowers the temperature sensitivity of the asphalt. It is equivalent to modifying the asphalt.

3. In the process of dry mixing and wet mixing of additives and stone and asphalt, some additives are drawn into plastics, which plays a role in fiber reinforcement.

4. The main component of the additive is polyolefin, so that the elastic component of the additive can restore the deformation of the asphalt pavement, thereby reducing the permanent deformation of the asphalt pavement.

Although the conventional "asphalt mixture additive" is directly added to the asphalt mixture, although the modulus of the asphalt mixture can be improved, there are two disadvantages in terms of the use effect and the like: 1. If the polyolefin in the additive is all new materials, the cost is high and it is difficult to promote; if some recycled polyolefin old materials are used as the component of the additive, when the additive is mixed with the stone and the asphalt is wet mixed, Due to the short mixing time, the additive cannot be completely melted and dispersed in a short time, which affects the performance of the mixture modulus.

2. The conventional mixture additive is a mixture of a plurality of polyolefins, and the adhesion to the mixture is not very good, so that the modulus of the asphalt mixture is improved, and the effect of improving the rutting resistance is better than that of the modified asphalt. Still not ideal.

In order to obtain a new type of asphalt mixture additive which can significantly improve the modulus of the asphalt mixture and has a low cost and excellent dispersibility, it is necessary to study from the raw material selection ratio and the production manufacturing process. Summary of the invention

In view of the deficiencies of the conventional asphalt mixture additive prepared by the prior art, the inventors have intensively studied and invented a high-strength structural asphalt material and a preparation method thereof, which include a new polyolefin material and an old polyolefin. Materials, inorganic fillers, ultrafine carbon black particles, organic acid anhydrides, antioxidants, characterized in that the proportion by weight of the mixture is: 25-30 parts of new polyolefin material, 57-67 parts of old polyolefin material, inorganic filler 3- 5 parts, 0.8-1 parts of ultrafine carbon black particles, 2-4.5 parts of organic acid anhydride, and 0.1-0.15 parts of antioxidant. Its production and preparation process is as follows:

A. The selected 25-30 parts by weight of the new polyolefin material and 57-67 parts by weight of the old polyolefin material are metered into the mixer, and the mixer is turned on for 30-40 minutes to be thoroughly mixed;

B, metering 3-5 parts by weight of the inorganic filler, 0.8-1 parts by weight of ultrafine carbon black particles and 0.1-0.15 parts by weight of the antioxidant into the mixer separately mixed with the new and old polyolefin;

C. The mixed material is introduced into a special modified twin-screw extruder at a certain flow rate and extruded together with 2.5-4.5 parts by weight of the organic acid anhydride;

D. Under the high temperature and strong extrusion of the special twin-screw machine, the new and old high polyolefins undergo intermolecular displacement, and a large number of unsaturated bonds are generated. These unsaturated bonds will react with the organic acid anhydride to produce stable and binding properties. And the elastic material with good dispersibility, and the inorganic filler and the nano-scale ultrafine carbon black particles are also fully combined with the new and old polyolefin;

E. The molten material extruded from the twin-screw extruder is cooled by water, and then granulated and packaged. Beneficial effect

A new type of asphalt mixture additive (named: high-strength structural asphalt material) preparation method, the high-strength structural asphalt material product obtained by the same as the "conventional asphalt mixture additive" through the above four aspects to improve the asphalt mixture Modulus, thereby improving the rutting resistance of the asphalt pavement and In addition to improving water damage resistance and low temperature cracking resistance, it also has the advantages of low production cost, good dispersion performance, and significant improvement in the modulus of the asphalt mixture.

1. High-strength structural asphalt products are compounded by a variety of polyolefins, a small amount of fillers and trace organic additives through special technical processing techniques. The total content of polyolefin is 90-95% by weight, using a unique production technology to improve the recycled polyolefin old materials (ie polyethylene PE old material, polypropylene PP old material and ethylene-vinyl acetate copolymer). The melt index of the EVA old material makes the melt index of the recycled old material reach 2.8 g/10 minutes or more, and the melt index of the recycled old material is improved, and the dispersion effect is correspondingly good. Under this technical condition, the 90-95% polyolefin material contained in the new additive "high-strength structural asphalt material" component of the mixture uses 70-80% recycled old polyolefin material, which can still be kept very good. Dispersibility, and the effect of increasing the modulus of the asphalt mixture is very obvious. Therefore, the production cost of high-strength structural asphalt is much lower than the production cost of conventional compound additives at home and abroad.

2. Using the process of chemical grafting of high polymer and organic acid anhydride, the new and old polyolefin materials in the high-strength structural asphalt material can produce high-polymer materials with certain binder properties, and improve the high-strength structural asphalt and stone materials. Bonding performance, due to the stronger adhesion to stone, the higher the resistance to high temperature deformation and rutting resistance of the asphalt mixture, so that the high strength structural asphalt material can improve the asphalt at the same application ratio than the conventional mixture additive. Modulus of the mixture.

Figure 1 is a preparation process flow.

Example 1

As shown in the figure, a high-strength structural asphalt material, including a new polyolefin material, an old polyolefin material, an inorganic filler, ultrafine carbon black particles, an organic acid anhydride, an antioxidant, is characterized in that the weight ratio thereof is: 25-30 parts of new polyolefin material, 57-67 parts of old polyolefin material, 3-5 parts of inorganic filler, 0.8-1 part of ultrafine carbon black particles, 2-4.5 parts of organic acid anhydride, and 0.1-0.15 parts of antioxidant; The production preparation process is as follows:

C. The mixed material is introduced into a special modified twin-screw extruder at a certain flow rate and extruded together with 2.5-4.5 parts by weight of the organic acid anhydride; D. Under the high temperature and strong extrusion of the special twin-screw machine, the new and old high polyolefins undergo intermolecular displacement, and a large number of unsaturated bonds are generated. These unsaturated bonds will react with the organic acid anhydride to produce stable and binding properties. And the elastic material with good dispersibility, and the inorganic filler and the nano-scale ultrafine carbon black particles are also fully combined with the new and old polyolefin;

E. The molten material extruded from the twin-screw extruder is cooled by water, and then granulated and packaged. Example 2:

A. The selected 28 parts by weight of the new polyolefin material and 62 parts by weight of the old polyolefin material are metered into the mixer, and the mixer is turned on for 30-40 minutes to be thoroughly mixed;

B. The metered 3.5 parts by weight of the inorganic filler, 0.86 parts by weight of the ultrafine carbon black particles, and 0.11 parts by weight of the antioxidant are respectively put into the mixer and thoroughly mixed with the new and old polyolefin;

C. The mixed material is introduced into a special modified twin-screw extruder at a certain flow rate and extruded together with 3.35 parts by weight of the organic acid anhydride;

E. The molten material extruded from the twin-screw extruder is cooled by water, and then granulated and packaged. Example 3:

The inorganic filler described in Example 1 and Example 2 is diatomaceous earth, the organic acid anhydride is a mixture of acetic anhydride and maleic anhydride, and the old polyolefin material is a mixture of high pressure polyethylene ion material PE and EVA material. The ultrafine carbon black particles are ultrafine nano-sized ultrafine carbon black particles. The acetic anhydride weight fraction is 1.5-2.5, the maleic anhydride weight fraction is 1-2, the high pressure polyethylene ion material PE weight fraction is 35-40, and the EVA material weight fraction is 22 -27.

Example 4:

The inorganic filler described in Example 1 and Example 2 is diatomaceous earth, the organic acid anhydride is a mixture of acetic anhydride and maleic anhydride, and the old polyolefin material is a mixture of high pressure polyethylene ion material PE and EVA material. The ultrafine carbon black particles are ultrafine nano-sized ultrafine carbon black particles. The acetic anhydride weight fraction is 2.15, the maleic anhydride weight fraction is 1.2, the high pressure polyethylene ion material PE weight The portion is 37, and the EVA material is 25 parts by weight.

The key to the preparation process is the ratio of raw materials. As long as the quality parameters of a certain raw material change, the ratio of other raw materials should be adjusted accordingly. Therefore, the raw materials for different sources must be experimentally determined, especially the recycled polyolefin. The quality of the old materials varies widely, and a lot of experiments are needed to ensure that the performance of the "high-strength structural asphalt material" meets the requirements for use.

The raw material ratio composition of the preparation method of the "high-strength structural asphalt material" according to the present invention is as follows (the solid and liquid components used in the raw material should be separately stored and transported according to chemical properties)

The following examples are further illustrative of the invention and are not intended to limit the scope of the invention.

Raw material ratio

No. Raw material name and specification model Weight fraction

1 new high pressure polyethylene particles (molecular weight 72000) 28

Recycled old high-pressure polyethylene pellets (content is

2 37

96%)

3 Recycled old EVA material (content 98.5%) 25

4 diatomite inorganic filler (325 mesh, content 99.6%) 3.5

5 nanometer ultrafine carbon black particles 0.86

6 acetic anhydride (content 99.7%) 2.15 7 Maleic anhydride (content 99.7%) 1.2

8 Anti-aging agent M 0.11

Quality index of "high-strength structural asphalt material" after implementation

Reference quality index

Test results and stiffness modulus test results of AC-20 asphalt mixture in different dosages

Description: According to the industry standard of China's Ministry of Communications, "Testing Procedures for Asphalt and Asphalt Mixtures"

(JTJ052-2000) and Jiangsu Baoli Asphalt Co., Ltd. enterprise standard Q/320281NYD01-2000 for testing.

Claims

Claim

1. A high-strength structural asphalt material, comprising a new polyolefin material, an old polyolefin material, an inorganic filler, ultrafine carbon black particles, an organic acid anhydride, an antioxidant, characterized in that the weight ratio thereof is: new polyolefin 25-30 parts, 57-67 parts of old polyolefin material, 3-5 parts of inorganic filler, 0.8-1 part of ultrafine carbon black particles, 2-4.5 parts of organic acid anhydride, and 0.1-0.15 parts of antioxidant.

2. A method of preparing a high strength structural asphalt material according to claim 1, wherein the production process is as follows:

E. The molten material extruded from the twin-screw extruder is cooled by water, and then granulated and packaged.

3. A method of preparing a high strength structural asphalt material according to claim 1, wherein the production process is as follows:

D. Under the high temperature and strong extrusion of the special twin-screw machine, the new and old high polyolefins undergo intermolecular displacement, and a large number of unsaturated bonds are generated. These unsaturated bonds will react with the organic acid anhydride to produce stable and binding properties. And dispersible elastic materials, as well as inorganic fillers and nano-scale ultra-fine carbon black particles The child is also fully integrated with the new and old polyolefins;

The method for preparing a high-strength structural asphalt according to claim 2 or 3, wherein the inorganic filler is diatomaceous earth, and the organic acid anhydride is a mixture of acetic anhydride and maleic anhydride, and the old polymer The olefin material is a mixture of high pressure polyethylene ion material PE and EVA material, and the ultrafine carbon black particles are ultrafine nano-sized ultrafine carbon black particles.

The method for preparing a high-strength structural asphalt according to claim 4, wherein the acetic anhydride is 1.5-2.5 parts by weight, and the maleic anhydride is 1-2 parts by weight. The polyethylene ion material PE is 35-40 parts by weight, and the EVA material is 22-27 parts by weight.

The method for preparing a high-strength structural asphalt according to claim 4, wherein the acetic anhydride is 2.15 parts by weight, the maleic anhydride is 1.2 parts by weight, and the high-pressure polyethylene ion material is The PE part by weight is 37, and the EVA material is 25 parts by weight.