The brittleness of modified asphalt is mainly related to what is in its composition?

The brittleness that affects the modified asphalt is mainly related to the wax content in the asphalt. Here are my other questions, please refer to them, in addition, the two substances you mentioned actually play a role in changing the content of the four components in the asphalt, if the aromatic hydrocarbon molecules are polymerized, then the gum content is increased, and the asphalt will become thicker.

Toluene-insoluble components of coal tar, coal tar bitumen and other similar products, referred to as TI; Quinoline insoluble matter is abbreviated as qi.

The qi in coal tar is produced when coal is coking (carbonized) and is commonly referred to as virgin qi. Because the qi in the coal tar is concentrated into the bitumen by tar distillation (medium temperature bitumen or soft bitumen), the amount of qi in the tar affects the bitumen qi. However, the qi content in the bitumen seriously affects the availability of the asphalt, therefore, the tar qi content is primary.

Medium-temperature asphalt with the same softening point but different quinoline insoluble matter (qi) content was used as raw material, and the thermal polymerization modification test of several types of coal asphalt was carried out. The results show that the Qi content of coal asphalt raw materials has a great influence on the thermal polymerization process and the performance indexes of the product modified asphalt, and the secondary Qi transformation rate of the modified asphalt during the thermal polymerization period is proportional to the Qi content of the raw coal asphalt.

Quinoline insoluble: coal tar is a mixture of many compounds, most of which are fully suitable for the production of needle coke, but the content of quinoline insoluble matter is more, and the asphalt obtained from this coal tar processing cannot be directly used to produce needle coke, so the quinoline insoluble matter in coal tar must be removed. Quinoline insoluble matter is referred to as qi, its average relative molecular weight is 1800 2600, the atomic ratio of C h is greater than that, according to the formation of qi can be divided into primary qi (primary qi) and secondary qi (secondary qi), primary qi is present in coal tar, coal tar distillation it is transferred to asphalt.

The secondary qi is an aromatic hydrocarbon polymer with a larger molecular weight formed by the asphalt during the heating process, which exists in the asphalt in the form of solid particles. The content of quinoline insoluble matter (qi) is conducive to improving the mechanical strength and conductivity of carbon products, and has a certain limiting effect on the expansion of carbon products in roasting. However, if the qi is too high, the fluidity of the asphalt will be reduced, which is not conducive to the processing of carbon products in the later stage.

At present, there are three main methods for removing quinoline insoluble substances: 1. Chemical treatment method: hydrogenation technology is adopted, but the process is complex and the cost is high.

2. Solvent treatment method: adding solvent treatment is widely used in industrial production by some enterprises, but the solvent consumption of this method is large, and the energy consumption of the whole process is high. 3. Mechanical separation method

High-speed centrifugation is used, but this method is in the preliminary stage and has not yet been popularized. Summary: The use of mechanical separation method can not only reduce production costs, but also meet the requirements of energy conservation and environmental protection.

The centrifuge with high speed and high separation factor has high torque and good separation effect, which can effectively reduce the insoluble matter of quinoline in coal tar.

Toluene insoluble: coal tar contains a certain amount of carbon black-like substances and polymer resins suspended in it, which determines its well-known color, which is composed of polymers, especially aromatic hydrocarbons or fused aromatic hydrocarbons with more carbon and less hydrogen. These small black particles or flocculent substances dispersed in the colloidal system of coal tar are insoluble in organic solvents such as benzene, toluene, pyridine and quinoline, collectively known as benzene insoluble matter or toluene insoluble, which have a great impact on the nature and quality of coal tar.

Toluene insoluble matter is referred to as TI, its average relative molecular weight is 1200 1800, the atomic ratio of C h is about about, the appearance is black-brown powder, and it has stable components. This component has thermoplasticity and participates in the formation of coke grid, and its coking value can reach 90 95, which plays an important role in aggregate coking, and Ti has a certain influence on the mechanical strength, density and conductivity of carbon products. In the carbon products industry, high-speed centrifugal separation is used to reduce the content of toluene insoluble matter in coal tar to meet the requirements of carbon products production process.

The asphalt used in construction must have certain physical properties. It should be elastic and plastic under low temperature conditions, have sufficient strength and stability under high temperature conditions, have the ability to resist "aging" under processing and use conditions, and should also have strong adhesion to various mineral materials and structural surfaces, as well as adaptability to component deformation and fatigue resistance. Usually the asphalt processed by the petroleum processing plant may not fully meet these requirements, especially most of the asphalt produced by Daqing Oilfield in China, if only the heat resistance (softening point) is controlled, it is difficult to meet the requirements in other aspects, resulting in serious leakage of asphalt waterproof roof, and short service life.

For this purpose, asphalt needs to be modified with rubber, resin and mineral filler source materials.

The modified types of petroleum asphalt are: mineral filler modified asphalt. Due to the wetting and adsorption of asphalt on mineral fillers, asphalt can be arranged on the surface of mineral particles (or fibers) in a monomolecular form to form a strong asphalt film, some call it "structural asphalt".

Structural asphalt has high viscosity and temperature stability. The outside of the structural asphalt layer is free asphalt, so that the asphalt mixture still has a certain toughness at low temperature. Rubber asphalt. Rubber is an important modified material of asphalt, which has good miscibility with asphalt, and can make asphalt have many advantages of rubber, such as small deformation at high temperature and good flexibility at low temperature; Synthetic resin-based modified asphalt.

The addition of synthetic resin can improve the waterproofness, cohesiveness and low-temperature performance of asphalt, especially the improvement effect of heat resistance and temperature stability.

1. Modification.

Whether the mix ratio of asphalt and sand is appropriate.

2. The binding capacity of modified asphalt and sand particles, which is related to the quality right and material quality of No. 70 asphalt construction version, such as hot work asphalt coke, water in the sand, and organic matter such as grass roots will reduce the binding force.

3. The thickness of the film formed by the modified asphalt binder and the maximum possible surface of the granular cement. Tests have proved (and construction has also proved that the total surface area between the sand particles determines the thickness of the asphalt film. When the modified asphalt content is constant, the finer the sand particles, the thinner the asphalt film and the higher the strength.

However, the asphalt film is so thin that it cannot wrap and bond the sand particles, and its strength will be drastically reduced.

Therefore, the total surface area of fine sand and extra-fine sand is large, and more road asphalt binder is required, and the total surface area of medium sand and coarse sand is smaller, and asphalt binder is less. In order to ensure the quality of modified asphalt more effectively. The solid is a black shiny semi-solid at room temperature, which gradually melts when heated and can be dissolved in organic solvents.

Moreover, the product has good fluidity, thermal stability, long-lasting adhesion, elastoplasticity, electrical insulation and water resistance, and the ductility is 40 100cm.