High-performance cable asphalt material

Abstract

The invention provides high-performance cable asphalt, and relates to the field of asphalt modification, and the high-performance cable asphalt is prepared from the following raw materials in parts by weight: 100 parts of matrix asphalt, 15-20 parts of rubber powder, 2-6 parts of polyphosphoric acid and 4-8 parts of high aromatic oil. The preparation method comprises the following steps: mixing the matrix asphalt, the high aromatic oil and the polyphosphoric acid, heating and stirring to obtain the polyphosphoric acid modified asphalt; and adding rubber powder into the polyphosphoric acid modified asphalt to prepare the high-performance cable asphalt. The high-performance cable asphalt provided by the invention is relatively good in coating uniformity, excellent in high-temperature performance while good low-temperature performance of the high-performance cable asphalt is ensured, and better in softening point, thermal stability and adhesion performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of asphalt modification, and particularly relates to a high-performance cable asphalt. Technical Background

[0002] According to the requirements of the national standard GB / T 11017-2002, 110KV high-voltage cables must be coated with cable asphalt material on the metal sheath as an anti-corrosion layer, and currently cable manufacturing enterprises also use asphalt as the anti-corrosion layer. Cable asphalt material, as a special asphalt, when coated on the outer layer of the cable, mainly plays roles such as sealing, anti-corrosion, and insulation. Compared with ordinary asphalt, as a special asphalt, it has the following characteristics: (1) high softening point and large penetration at the same time; (2) good thermal stability; (3) good adhesion and excellent low-temperature performance. However, as a special asphalt product, most of its suppliers are small and medium-sized private enterprises with weak scientific and technological R & D capabilities, and the product quality is uneven. The following problems mainly exist in terms of product quality: (1) poor adhesion rate between asphalt and metal sheath and armored metal wire; (2) poor high-temperature performance of asphalt in summer, resulting in dripping phenomenon; (3) when it is at low temperature in winter, the asphalt coating layer breaks and peels off after bending; (4) when coating in the factory, there are solid particles in the asphalt, resulting in poor uniformity. Summary of the Invention

[0003] The purpose of the present invention is to provide a high-performance cable asphalt with excellent product performance, which solves the above technical problems.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions: On the one hand, the present invention provides a high-performance cable asphalt, which is prepared from the following raw materials in parts by weight: 100 parts of matrix asphalt, 15 - 20 parts of rubber powder, 2 - 6 parts of polyphosphoric acid, and 4 - 8 parts of high-aromatic oil. The preparation steps are as follows: Mix matrix asphalt, high-aromatic oil, and polyphosphoric acid and heat and stir to obtain polyphosphoric acid-modified asphalt; then add rubber powder to the polyphosphoric acid-modified asphalt and heat and stir to prepare the high-performance cable asphalt.

[0005] Preferably, the particle size of the rubber powder is 30 - 60 mesh.

[0006] Preferably, the high-aromatic oil includes any one of rubber oil, furfural extract oil, or reduced-fourth-line extract oil.

[0007] Preferably, the phosphoric acid content of the polyphosphoric acid is not less than 105%. The content of polyphosphoric acid is mainly detected by the phosphorus content. Comparing with the reference substance, more phosphorus groups are complexed, resulting in a result exceeding 100%.

[0008] Preferably, the matrix asphalt has a penetration of 60 - 80 at 25°C and 0.1 mm. Penetration is an index for measuring the hardness and consistency of a substance and is usually used to evaluate the properties of substances such as grease and asphalt.

[0009] On the other hand, the present invention discloses a method for preparing the above-mentioned high-performance cable asphalt, which includes the following steps: S1. Heat the matrix asphalt to a molten state, add high-aromatic oil and polyphosphoric acid, and heat and stir for chemical modification to obtain polyphosphoric acid-modified asphalt. S2. Add rubber powder to the polyphosphoric acid-modified asphalt, and heat and stir for TB rubber powder modification to obtain high-performance cable asphalt.

[0010] Preferably, in step S1, the temperature of the chemically modified asphalt is 190 - 200°C and the time is 6 - 8 h.

[0011] Preferably, in step S2, the temperature of the TB rubber powder modification is 210 - 240°C and the time is 8 - 14 h.

[0012] The present invention adopts a composite modification coexisting with TB rubber powder modification and polyphosphoric acid chemical modification. The TB rubber powder modification process is essentially a degradation process of rubber powder. Applying it to the field of cable asphalt can solve the problem of poor thermal stability of conventional polymers. The degradation process includes two reactions: desulfurization and depolymerization. The desulfurization and depolymerization reactions greatly reduce the particle size of the rubber powder, and finally these rubber particles can be completely dissolved in the liquid phase of the asphalt, improving the thermal stability of the product; in addition, the low-temperature flexibility of the asphalt itself is also significantly improved, and it is not easy to break in winter; on the other hand, the overall product is a homogeneous structure, ensuring the uniformity during factory coating.

[0013] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: The method for preparing high-performance cable asphalt disclosed by the present invention adds high-aromatic oil and polyphosphoric acid to the matrix asphalt in a molten state, and heats and stirs to chemically modify the matrix asphalt. By adding polyphosphoric acid, the saturated fraction and aromatic fraction in the matrix asphalt are converted into asphaltene and resin, increasing the number of micelles, improving the anti-deformation ability such as asphalt sag and high-temperature properties such as softening point; at the same time, the polar functional groups of polyphosphoric acid itself also enhance the adhesion of the asphalt product, solving the problems of summer dripping and winter breakage and shedding of the cable asphalt products prepared by traditional methods; preferably, during the chemical modification process, the modification temperature is controlled at 190 - 200°C and the modification time is controlled at 6 - 8 h. If the modification temperature is too low or the modification time is too short, it is easy to cause insufficient reaction between polyphosphoric acid and asphalt, poor modification effect, and poor high-temperature properties such as softening point and anti-deformation ability such as sag; if the temperature is too high or the modification time is too long, the asphalt is prone to aging, becoming hard and brittle, and having poor low-temperature crack resistance.

[0014] The disclosed method for preparing high-performance cable asphalt of the present invention heats and raises the temperature of polyphosphoric acid-modified asphalt, then adds rubber powder for TB rubber powder modification. The rubber powder undergoes desulfurization and degradation reactions in the asphalt and forms a homogeneous system with the asphalt, making the asphalt product have excellent low-temperature performance and thermal stability. Preferably, the particle size of the rubber powder is selected to be 30-60 mesh, the TB rubber powder modification temperature is controlled at 210-240 °C, and the modification time is controlled at 8-14 h. If the modification temperature is low, the modification time is short, or the particle size of the rubber powder is too large, the TB rubber powder modification is insufficient, and there will be rubber powder particles in the asphalt, reducing its thermal stability and cold bending performance. If the modification temperature is too high, the modification time is too long, or the particle size of the rubber powder is too small, the TB rubber powder modification is excessive, the light components in the asphalt are too low, and the product becomes "hard and brittle", reducing the low-temperature performance of the product.

[0015] (3)The disclosed method for preparing high-performance cable asphalt of the present invention uses polyphosphoric acid and rubber powder to perform composite modification on matrix asphalt. A synergistic effect is formed between polyphosphoric acid and rubber powder. Under the action of polyphosphoric acid, the rubber powder crosslinks inside the asphalt. In addition, high-aromatic oil supplements the content of light components in the asphalt, enabling the rubber powder to crosslink better inside the asphalt, and then forming a relatively developed network structure. The cross-sectional area of the asphalt becomes larger, further improving the adhesion ability and anti-deformation abilities such as sag and cold bending of the product. If there is too little high-aromatic oil, the crosslinking of the rubber powder is insufficient, and the improvement of the cold bending and other abilities of the product is insufficient. If there is too much high-aromatic oil, there are too many light components in the asphalt, and the flash point of the product decreases, which is not conducive to safe production. Preferably, the ratio of polyphosphoric acid, rubber powder, and high-aromatic oil is controlled at 2-6:15-20:4-8.

[0016] (4)The high-performance cable asphalt product prepared by the present invention has rubber particles completely dissolved in the liquid phase of the asphalt, and the product as a whole has a homogeneous structure, ensuring the uniformity of factory coating. Compared with other polymer-modified asphalts, this product has more excellent thermal stability, which is convenient for storage and transportation. It has good adhesion performance and low-temperature performance, and will not fall off and crack in cold winter environments. At the same time, it has a higher softening point and excellent high-temperature performance, and will not drip in high-temperature summer environments. The high-performance cable asphalt product of the present invention has a penetration (0.1 mm) of about 60 at 25 °C, a softening point of about 90 °C, its low-temperature cold bending is qualified at -15 °C, and its low-temperature anti-cracking performance is excellent. It has good thermal storage stability. After heat storage at 200 °C for 24 h, the softening point and penetration basically remain unchanged, and the overall performance meets the technical indicators of the industry standard NB / SH / T0001-2019.

[0017] (5)The present invention adopts a two-step preparation process. Compared with the prior art, it reduces the process of adding stabilizers for heat preservation and development in conventional polymer-modified asphalt. The preparation process is simple, the raw materials of rubber powder and polyphosphoric acid are easily available, and the produced high-performance cable asphalt product has excellent performance and is highly valuable for promotion. Description of the Drawings

[0018] Figure 1 Infrared spectrum diagram of the matrix asphalt and polyphosphoric acid modified asphalt in Example 1 Figure 2 Scanning electron microscope image of the matrix asphalt in Example 1 Figure 3 Scanning electron microscope image of the high-performance cable asphalt in Comparative Example 7 Figure 4 Scanning electron microscope image of the TB rubber powder modified asphalt in Comparative Example 1 Figure 5 Scanning electron microscope image of the high-performance cable asphalt in Example 1 Detailed Description of the Invention

[0019] Hereinafter, embodiments of the technical solution of the present invention will be described in detail. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and thus are only examples and cannot be used to limit the protection scope of the present invention.

[0020] It should be noted that unless otherwise specified, the technical terms or scientific terms used in this application should have the ordinary meaning understood by those skilled in the art to which the present invention belongs. Example 1

[0021] This example provides a high-performance cable asphalt, which is made from the following raw materials in parts by weight: 100 parts of matrix asphalt, 18 parts of rubber powder, 4 parts of polyphosphoric acid, and 5 parts of high-aromatic oil.

[0022] Among them, the penetration of the matrix asphalt at 25 °C and 0.1 mm is 75.

[0023] The particle size of the rubber powder is 40 mesh.

[0024] The high-aromatic oil is rubber oil.

[0025] The phosphoric acid content of the polyphosphoric acid is 105%.

[0026] This example also provides a preparation method for the above high-performance cable asphalt, including the following steps: S1. Heat the matrix asphalt to a molten state, then add the high-aromatic oil and polyphosphoric acid, continue to heat to 195 °C, keep stirring for 7 h, and carry out chemical modification to obtain polyphosphoric acid modified asphalt.

[0027] S2. Heat the polyphosphoric acid modified asphalt to 220 °C, add the rubber powder, keep stirring for 10 h, and carry out TB rubber powder modification to obtain high-performance cable asphalt.

[0028] The high-performance cable asphalt prepared in this example is used for the cable armor layer and is applied in a coating manner. Example 2

[0029] This embodiment provides a high-performance cable asphalt, which is made of the following raw materials in parts by weight: 100 parts of matrix asphalt, 15 parts of rubber powder, 2 parts of polyphosphoric acid, and 4 parts of high-aromatic oil.

[0030] Among them, the penetration of the matrix asphalt at 25 °C and 0.1 mm is 60.

[0031] The particle size of the rubber powder is 60 mesh.

[0032] The high-aromatic oil is furfural-extracted oil.

[0033] The phosphoric acid content of the polyphosphoric acid is 110%.

[0034] This embodiment also provides a preparation method of the above-mentioned high-performance cable asphalt, which includes the following steps: S1. Heat the matrix asphalt to a molten state, then add the high-aromatic oil and polyphosphoric acid, continue to heat to 190 °C, keep warm and stir for 6 h, and carry out chemical modification to obtain polyphosphoric acid-modified asphalt.

[0035] S2. Heat the polyphosphoric acid-modified asphalt to 210 °C, add the rubber powder, keep warm and stir for 8 h, and carry out TB rubber powder modification to obtain high-performance cable asphalt.

[0036] The high-performance cable asphalt prepared in this embodiment is used for the cable armor layer and is applied in a coating manner. Example 3

[0037] This embodiment provides a high-performance cable asphalt, which is made of the following raw materials in parts by weight: 100 parts of matrix asphalt, 20 parts of rubber powder, 6 parts of polyphosphoric acid, and 8 parts of high-aromatic oil.

[0038] Among them, the penetration of the matrix asphalt at 25 °C and 0.1 mm is 80.

[0039] The particle size of the rubber powder is 30 mesh.

[0040] The high-aromatic oil is the fourth-line reduced-pressure extracted oil.

[0041] The phosphoric acid content of the polyphosphoric acid is 105%.

[0042] This embodiment also provides a preparation method of the above-mentioned high-performance cable asphalt, which includes the following steps: S1. Heat the matrix asphalt to a molten state, then add the high-aromatic oil and polyphosphoric acid, continue to heat to 200 °C, keep warm and stir for 8 h, and carry out chemical modification to obtain polyphosphoric acid-modified asphalt.

[0043] S2. Heat the polyphosphoric acid-modified asphalt to 240 °C, add the rubber powder, keep warm and stir for 14 h, and carry out TB rubber powder modification to obtain high-performance cable asphalt.

[0044] The high-performance cable asphalt prepared in this example is used for the cable armor layer and is applied by coating. Example 4

[0045] This example provides a high-performance cable asphalt, which is made from the following raw materials in parts by weight: 100 parts of matrix asphalt, 16 parts of rubber powder, 3 parts of polyphosphoric acid, and 6 parts of high-aromatic oil.

[0046] Among them, the penetration of the matrix asphalt at 25 °C and 0.1 mm is 75.

[0047] The particle size of the rubber powder is 40 mesh.

[0048] The high-aromatic oil is rubber oil.

[0049] The phosphoric acid content of the polyphosphoric acid is 105%.

[0050] This example also provides a preparation method for the above-mentioned high-performance cable asphalt, which includes the following steps: S1. Heat the matrix asphalt to a molten state, then add the high-aromatic oil and polyphosphoric acid, continue to heat to 192 °C, keep warm and stir for 7 h for chemical modification to obtain polyphosphoric acid-modified asphalt.

[0051] S2. Heat the polyphosphoric acid-modified asphalt to 210 °C, add the rubber powder, keep warm and stir for 9 h for TB rubber powder modification to obtain high-performance cable asphalt.

[0052] The high-performance cable asphalt prepared in this example is used for the cable armor layer and is applied by coating. Example 5

[0053] This example provides a high-performance cable asphalt, which is made from the following raw materials in parts by weight: 100 parts of matrix asphalt, 19 parts of rubber powder, 5 parts of polyphosphoric acid, and 7 parts of high-aromatic oil.

[0054] Among them, the penetration of the matrix asphalt at 25 °C and 0.1 mm is 75.

[0055] The particle size of the rubber powder is 40 mesh.

[0056] The high-aromatic oil is rubber oil.

[0057] The phosphoric acid content of the polyphosphoric acid is 105%.

[0058] This example also provides a preparation method for the above-mentioned high-performance cable asphalt, which includes the following steps: S1. Heat the matrix asphalt to a molten state, then add the high-aromatic oil and polyphosphoric acid, continue to heat to 198 °C, keep warm and stir for 7 h for chemical modification to obtain polyphosphoric acid-modified asphalt.

[0059] S2. Heat the polyphosphoric acid modified asphalt to 230°C, add the rubber powder, keep it warm and stir for 12 hours to carry out TB rubber powder modification to obtain high-performance cable asphalt.

[0060] The high-performance cable asphalt prepared in this example is used for the cable armor layer and is applied in a coating manner. Comparative Example 1

[0061] Comparative Example 1 is based on Example 1 with the change in the raw material ratio. The change is that polyphosphoric acid is not added, and the rest of the operations are the same.

[0062] This comparative example provides a TB rubber powder modified asphalt, which is made from the following raw materials in parts by weight: 100 parts of matrix asphalt, 18 parts of rubber powder, and 5 parts of high-aromatic oil.

[0063] Among them, the penetration of the matrix asphalt at 25°C and 0.1 mm is 75.

[0064] The particle size of the rubber powder is 40 mesh.

[0065] The high-aromatic oil is rubber oil.

[0066] This comparative example also provides a preparation method for the above-mentioned TB rubber powder modified asphalt, including the following steps: S1. Heat the matrix asphalt to the molten state, then add the high-aromatic oil, continue to heat to 195°C, keep it warm and stir for 7 hours to carry out chemical modification to obtain the blended asphalt.

[0067] S2. Heat the blended asphalt to 220°C, add the rubber powder, keep it warm and stir for 10 hours to carry out TB rubber powder modification to obtain the TB rubber powder modified asphalt. Comparative Example 2

[0068] Comparative Example 2 is based on Example 1 with the change in the raw material ratio. The change is that the rubber powder is not added, and the rest of the operations are the same.

[0069] This comparative example provides a polyphosphoric acid modified asphalt, which is made from the following raw materials in parts by weight: 100 parts of matrix asphalt, 4 parts of polyphosphoric acid, and 5 parts of high-aromatic oil.

[0070] Among them, the penetration of the matrix asphalt at 25°C and 0.1 mm is 75.

[0071] The high-aromatic oil is rubber oil.

[0072] The phosphoric acid content of the polyphosphoric acid is 105%.

[0073] This comparative example also provides a preparation method for the above-mentioned TB rubber powder modified asphalt, including the following steps: S1. Heat the base asphalt to a molten state, then add high-aromatic oil and polyphosphoric acid, continue heating to 195 °C, keep warm and stir for 7 h to conduct chemical modification to obtain the blended asphalt.

[0074] S2. Heat the blended asphalt to 220 °C, keep warm and stir for 10 h to obtain the polyphosphoric acid modified asphalt. Comparative Example 3

[0075] Comparative Example 3 makes changes to the raw material ratio on the basis of Example 1. The changes are as follows: reduce the content of rubber powder, increase the content of polyphosphoric acid, and reduce the content of high-aromatic oil.

[0076] This comparative example provides a high-performance cable asphalt, which is made of the following raw materials in parts by weight: 100 parts of base asphalt, 12 parts of rubber powder, 8 parts of polyphosphoric acid, and 2 parts of high-aromatic oil.

[0077] Among them, the penetration of the base asphalt at 0.1 mm at 25 °C is 75.

[0078] The particle size of the rubber powder is 40 mesh.

[0079] The high-aromatic oil is rubber oil.

[0080] The phosphoric acid content of the polyphosphoric acid is 105%.

[0081] This comparative example also provides a preparation method of the above high-performance cable asphalt, which includes the following steps: S1. Heat the base asphalt to a molten state, then add high-aromatic oil and polyphosphoric acid, continue heating to 195 °C, keep warm and stir for 7 h to conduct chemical modification to obtain the polyphosphoric acid modified asphalt.

[0082] S2. Heat the polyphosphoric acid modified asphalt to 220 °C, add rubber powder, keep warm and stir for 10 h to conduct TB rubber powder modification to obtain the high-performance cable asphalt. Comparative Example 4

[0083] Comparative Example 4 makes changes to the raw material ratio on the basis of Example 1. The changes are as follows: increase the content of rubber powder, reduce the content of polyphosphoric acid, and increase the content of high-aromatic oil.

[0084] This comparative example provides a high-performance cable asphalt, which is made of the following raw materials in parts by weight: 100 parts of base asphalt, 25 parts of rubber powder, 1 part of polyphosphoric acid, and 10 parts of high-aromatic oil.

[0085] Among them, the penetration of the base asphalt at 0.1 mm at 25 °C is 75.

[0086] The particle size of the rubber powder is 40 mesh.

[0087] The high-aromatic oil is rubber oil.

[0088] The phosphoric acid content of polyphosphoric acid is 105%.

[0089] This comparative example also provides a method for preparing the above-mentioned high-performance cable asphalt, including the following steps: S1. Heat the base asphalt to a molten state, then add high-aromatic oil and polyphosphoric acid, continue to heat to 195 °C, keep warm and stir for 7 h for chemical modification to obtain polyphosphoric acid-modified asphalt.

[0090] S2. Heat the polyphosphoric acid-modified asphalt to 220 °C, add rubber powder, keep warm and stir for 10 h for TB rubber powder modification to obtain high-performance cable asphalt. Comparative Example 5

[0091] Comparative Example 5 is a change in process conditions based on Example 1. The changes are as follows: reduce the chemical modification temperature and shorten the chemical modification time, and the rest of the operations are the same.

[0092] This comparative example provides a high-performance cable asphalt made from the following raw materials in parts by weight: 100 parts of base asphalt, 18 parts of rubber powder, 4 parts of polyphosphoric acid, and 5 parts of high-aromatic oil.

[0093] Among them, the penetration at 0.1 mm of the base asphalt at 25 °C is 75.

[0094] The particle size of the rubber powder is 40 mesh.

[0095] The high-aromatic oil is rubber oil.

[0096] The phosphoric acid content of polyphosphoric acid is 105%.

[0097] This comparative example also provides a method for preparing the above-mentioned high-performance cable asphalt, including the following steps: S1. Heat the base asphalt to a molten state, then add high-aromatic oil and polyphosphoric acid, continue to heat to 180 °C, keep warm and stir for 5 h for chemical modification to obtain polyphosphoric acid-modified asphalt.

[0098] S2. Heat the polyphosphoric acid-modified asphalt to 220 °C, add rubber powder, keep warm and stir for 10 h for TB rubber powder modification to obtain high-performance cable asphalt. Comparative Example 6

[0099] Comparative Example 6 is a change in process conditions based on Example 1. The changes are as follows: increase the chemical modification temperature and extend the chemical modification time, and the rest of the operations are the same.

[0100] This comparative example provides a high-performance cable asphalt made from the following raw materials in parts by weight: 100 parts of base asphalt, 18 parts of rubber powder, 4 parts of polyphosphoric acid, and 5 parts of high-aromatic oil.

[0101] Among them, the penetration of the base asphalt at 25°C is 75 at 0.1 mm.

[0102] The particle size of the rubber powder is 40 mesh.

[0103] The high-aromatic oil is rubber oil.

[0104] The phosphoric acid content of the polyphosphoric acid is 105%.

[0105] This comparative example also provides a preparation method of the above-mentioned high-performance cable asphalt, including the following steps: S1. Heat the base asphalt to a molten state, then add the high-aromatic oil and polyphosphoric acid, continue to heat to 210°C, keep warm and stir for 10 h for chemical modification to obtain polyphosphoric acid-modified asphalt.

[0106] S2. Heat the polyphosphoric acid-modified asphalt to 220°C, add the rubber powder, keep warm and stir for 10 h for TB rubber powder modification to obtain high-performance cable asphalt. Comparative Example 7

[0107] Comparative Example 7 is a modification based on Example 1. The changes are as follows: lower the TB rubber powder modification temperature, shorten the TB rubber powder modification time, and increase the particle size of the rubber powder, and the rest of the operations are the same.

[0108] This comparative example provides a high-performance cable asphalt, which is made from the following raw materials in parts by weight: 100 parts of base asphalt, 18 parts of rubber powder, 4 parts of polyphosphoric acid, and 5 parts of high-aromatic oil.

[0109] Among them, the penetration of the base asphalt at 25°C is 75 at 0.1 mm.

[0110] The particle size of the rubber powder is 20 mesh.

[0111] The high-aromatic oil is rubber oil.

[0112] The phosphoric acid content of the polyphosphoric acid is 105%.

[0113] This comparative example also provides a preparation method of the above-mentioned high-performance cable asphalt, including the following steps: S1. Heat the base asphalt to a molten state, then add the high-aromatic oil and polyphosphoric acid, continue to heat to 210°C, keep warm and stir for 10 h for chemical modification to obtain polyphosphoric acid-modified asphalt.

[0114] S2. Cool the polyphosphoric acid-modified asphalt to 190°C, add the rubber powder, keep warm and stir for 8 h for TB rubber powder modification to obtain high-performance cable asphalt. Comparative Example 8

[0115] Comparative Example 8 was modified based on Example 1. The modifications were as follows: increasing the modification temperature of the TB rubber powder, extending the modification time of the TB rubber powder, and reducing the particle size of the rubber powder. The rest of the operations were the same.

[0116] This comparative example provides a high-performance cable asphalt, which is made from the following raw materials in parts by weight: 100 parts of matrix asphalt, 18 parts of rubber powder, 4 parts of polyphosphoric acid, and 5 parts of high-aromatic oil.

[0117] The penetration of the matrix asphalt at 0.1 mm at 25°C is 75.

[0118] The particle size of the rubber powder is 80 mesh.

[0119] The high-aromatic oil is rubber oil.

[0120] The phosphoric acid content of the polyphosphoric acid is 105%.

[0121] This comparative example also provides a preparation method for the above high-performance cable asphalt, which includes the following steps: S1. Heat the matrix asphalt to a molten state, then add the high-aromatic oil and polyphosphoric acid, continue heating to 210°C, and keep stirring for 10 h for chemical modification to obtain polyphosphoric acid-modified asphalt.

[0122] S2. Cool the polyphosphoric acid-modified asphalt to 260°C, add the rubber powder, and keep stirring for 18 h for TB rubber powder modification to obtain high-performance cable asphalt.

[0123] Test the various indexes of the high-performance cable asphalt prepared in Examples 1-5, and the results are shown in Table 1.

[0124] Test the various indexes of the high-performance cable asphalt prepared in Comparative Examples 1-8, and the results are shown in Table 2.

[0125] The industry standard for cable asphalt is shown in Table 3.

[0126]

[0127]

[0128]

[0129] In Table 2, No. 1 is applicable to onshore cables in southern regions, No. 2 is applicable to onshore cables in northern regions, and No. 3 is applicable to submarine cables.

[0130] Comparative Examples 1-8 in Table 2 are based on Example 1 in Table 1, reflecting the influence of raw material ratios and process conditions on the performance of high-performance cable asphalt.

[0131] As can be seen from Table 1, the cable asphalt prepared by the present method has a relatively high softening point, and good test results for cold bending, sag and adhesion. It shows that the product has excellent high and low temperature performance and adhesion performance, which can effectively prevent bending fracture and dripping.

[0132] As can be seen from Table 2, for the TB rubber powder modified asphalt prepared in Comparative Example 1, no polyphosphoric acid was added, and its high temperature performance such as softening point was poor, the adhesion performance was poor, and the sag index was also unqualified; for the asphalt product prepared in Comparative Example 2, no rubber powder was added, and its low temperature performance such as cold bending was poor, and the thermal stability performance was poor; by comparing Comparative Example 1, Comparative Example 2 and Example 1, it was found that under the synergistic effect of polyphosphoric acid and rubber powder, the high and low temperature performance and adhesion performance of the high-performance cable asphalt product were significantly improved, and the anti-deformation performance such as sag was also improved. Comparative Examples 3 and 4 reflect the influence of the ratio of polyphosphoric acid, rubber powder and high-aromatic oil in the composite modification. In Comparative Example 3, the rubber powder content was reduced, the polyphosphoric acid content was increased, and the high-aromatic oil content was reduced. The excessive polyphosphoric acid content made the high temperature performance such as the softening point of the product too high and the penetration too small. The small content of high-aromatic oil and rubber powder made the cross-linking of rubber powder and polyphosphoric acid insufficient, and the cold bending performance of the product was poor, and the overall performance of the product was not good; in Comparative Example 4, the rubber powder content was increased, the polyphosphoric acid content was reduced, and the high-aromatic oil content was increased. The too small polyphosphoric acid content made the softening point of the product lower, the adhesion performance unqualified, and the improvement of the high temperature performance insufficient. The excessive high-aromatic oil content made the flash point of the product lower. Comparative Examples 5 and 6 reflect the influence of the temperature and time of polyphosphoric acid chemical modification. In Comparative Example 5, the chemical modification temperature was reduced and the chemical modification time was shortened. The polyphosphoric acid chemical modification was insufficient, and the softening point and sag performance of the product were not good; in Comparative Example 6, the chemical modification temperature was increased and the chemical modification time was increased, and the asphalt aging phenomenon was serious, the softening point of the product was too high, the penetration was too low, and the cold bending performance was unqualified. Comparative Examples 7 and 8 reflect the influence of the temperature and time of TB rubber powder modification and the influence of the rubber powder particle size. In Comparative Example 7, the TB rubber powder modification temperature was reduced, the TB rubber powder modification time was shortened, and the rubber powder particle size was increased. The TB rubber powder modification was insufficient, and obvious solid particles were present in the product, the softening point was relatively high, and the cold bending performance was not improved enough. At the same time, in the thermal stability, the softening point decreased and the penetration increased, affecting the product quality; in Comparative Example 8, the TB rubber powder modification temperature was increased, the TB rubber powder modification time was extended, and the rubber powder particle size was reduced, and the asphalt aging phenomenon occurred, the softening point of the product was too high, the penetration was too low, and the cold bending performance was not good and the adhesion was insufficient. By comparing Table 1 and Table 2, it can be seen that the high-performance cable asphalt provided by the present invention meets the overall requirements of No. 1, No. 2 and No. 3 cable asphalt specified in the national standard NB / SH / T 0001-2019.

[0133] The essence of the modification process of TB rubber powder is essentially a degradation process of rubber powder, and the degradation process includes two reactions: desulfurization and depolymerization. The desulfurization and depolymerization reactions significantly reduce the particle size of the rubber powder. Eventually, these rubber particles can be completely dissolved in the liquid phase of the asphalt, improving the thermal stability of the product. In addition, the low-temperature flexibility of the asphalt itself is also significantly improved, and it is not easy to break in winter. On the other hand, the overall product is a homogeneous structure, ensuring the uniformity during factory coating.

[0134] On the one hand, the chemical modification of polyphosphoric acid converts the saturates and aromatics in the matrix asphalt into asphaltenes and resins, making its colloidal structure develop from a sol type to a gel type, improving the anti-deformation ability such as the asphalt sag and penetration. At the same time, the high-temperature properties such as the softening point and thermal stability of the asphalt are also improved. On the other hand, the chemical modification of polyphosphoric acid increases the macromolecular micelle substances in the asphalt. The high-performance cable asphalt prepared by it has better anti-permanent deformation ability and high-temperature performance, improving the phenomena of dripping in summer and breaking and falling off in winter.

[0135] The addition of polyphosphoric acid, with its polar functional groups, enhances the adhesion of the high-performance cable asphalt, enabling the high-performance cable asphalt to better wrap around the cable armor layer.

[0136] For Figure 1 Analysis found that compared with the matrix asphalt, the polyphosphoric acid-modified asphalt shows a symmetric stretching vibration of phosphate ester near 939 cm -1 , indicating that polyphosphoric acid reacts with chemical bonds such as in the asphalt to form chemical bonds such as . With the increase in the degree of esterification, in the asphalt dehydrates and condenses with polyphosphoric acid, and the content of macromolecular micelle substances in the asphalt increases, and the carbon chain becomes longer. Macroscopically, it is reflected that the high-temperature properties such as the softening point of the asphalt are improved. In addition, the intensity of the vibration absorption peaks at 3100 - 3700 cm and 1100 - 1000 cm -1 and 1100 - 1000 cm -1 indicates the physical addition of polyphosphoric acid. The polar functional groups of polyphosphoric acid itself improve the adhesion of the product, verifying that the TB rubber powder-modified asphalt prepared in Comparative Example 1 has poor high-temperature properties such as the softening point of the product, poor adhesion performance, and unqualified sag index.

[0137] For Figure 2 Observation found that under the microscopic image of the scanning electron microscope, the surface of the matrix asphalt is smooth and the texture is uniform. For the TB rubber powder-modified asphalt in Comparative Example 7, as Figure 3 shown, compared with Figure 5 , the rubber powder is not completely dissolved in the asphalt, and most of the rubber powder is still irregularly distributed in the asphalt in the form of free particles, which will lead to poor coating uniformity during factory coating. For Figure 4Analysis shows that in Comparative Example 1, the TB rubber powder modified asphalt presents a uniform and continuous phase with a "smooth" surface state, improving the coating uniformity. At the same time, the TB rubber powder modification technology enables the rubber powder to absorb the light components of the matrix asphalt during the physical and chemical reactions of vulcanization and degradation, and the side chain grafting reaction is sufficient, improving the thermal stability of the asphalt. Figure 5 Analysis shows that relative to Figure 4 , after adding polyphosphoric acid to the high-performance cable asphalt, under the action of polyphosphoric acid, the rubber powder cross-links inside the asphalt, forming a relatively developed network structure inside the asphalt, increasing the cross-sectional area of the asphalt, and improving the adhesion ability and anti-deformation ability of the asphalt. Macroscopically, the adhesion, sag and cold bending properties of the high-performance cable asphalt are improved.

[0138] The above embodiments further explain the technical solution of the present invention, rather than limiting the technical solution of the present invention. Those of ordinary skill in the art should know that without departing from the principle of the present invention, some or all of the technologies of the present invention can still be equivalently replaced, and these equivalent replacements should all be covered by the protection scope of the claims of the present invention.

Claims

1. A high performance cable asphalt, characterized in that: The high-performance cable asphalt is prepared from the following raw material components in parts by weight: 100 parts of base asphalt, 15-20 parts of rubber powder, 2-6 parts of polyphosphoric acid, and 4-8 parts of high aromatic oil; The preparation steps are as follows: The base asphalt, high aromatic oil and polyphosphoric acid are mixed and heated and stirred to obtain polyphosphoric acid modified asphalt; rubber powder is added to the polyphosphoric acid modified asphalt and heated and stirred to obtain high-performance cable asphalt.

2. The high performance cable asphalt according to claim 1, characterized in that: The base asphalt has a 0.1mm needle penetration of 60-80 at 25°C; the high aromatic oil includes any one of rubber oil, furfural extracted oil or reduced four-line extracted oil; and the rubber powder particle size is 30-60 meshes.

3. The high performance cable asphalt according to claim 1 or 2, characterized in that: The phosphoric acid content of the polyphosphoric acid is not less than 105wt%.

4. The method for preparing high performance cable asphalt according to claim 1, characterized in that: The matrix asphalt, high aromatic oil and polyphosphoric acid are mixed and heated and stirred at a temperature of 190-200° C. for 6-8 hours.

5. The method for preparing high-performance cable asphalt according to claim 1, characterized in that: The rubber powder is added to the polyphosphoric acid modified asphalt and heated and stirred at a temperature of 210-240° C. for 8-14 hours.

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