A waste cable derived polymer modified asphalt and a method of making the same

Abstract

This invention relates to the field of road engineering materials and the resource utilization of solid waste polymers, and discloses a modified asphalt made from waste cable-derived polymers and its preparation method. The modified asphalt consists of base asphalt, waste cable-derived modified components, compatibility-stabilizing and regulating components, and functional additives. The waste cable-derived modified components are subjected to conductor separation, purification, and drying refinement, followed by high-shear chain scission activation at 180-200℃, and polar groups are introduced through organic peroxide-induced grafting, subsequently coated with a reactive compatibilizer. During preparation, the base asphalt is heated to 150-190℃, the modified components are added in batches and dispersed under high shear, and after adding the compatibility-stabilizing and regulating components, defoaming and homogenization are performed to obtain the finished product. This invention can improve the dispersion and interfacial bonding of waste cable-derived polymers in asphalt, reduce the risk of segregation, improve storage stability and high-temperature rutting resistance, and realize the high-value resource utilization of waste cables.

Description

Technical Field

[0001] This application relates to the field of road engineering materials and solid waste polymer resource utilization, specifically to a polymer-modified asphalt derived from waste cables and its preparation method. Background Technology

[0002] Waste cables typically consist of a metal conductor, an insulation layer, and a sheath. The insulation and sheath layers mainly include polyethylene (PE), cross-linked polyethylene (XLPE), ethylene propylene rubber (EPR), and polyvinyl chloride (PVC). Existing methods for disposing of waste cables, such as incineration, landfill, and low-value recycling, result in resource waste and environmental pollution.

[0003] On the other hand, road asphalt is prone to rutting deformation at high temperatures and aging and hardening under the coupled effects of water, heat, and oxygen, leading to low-temperature cracking. Conventional modification techniques, such as using SBS and waste tire rubber powder to modify asphalt, can improve performance, but they suffer from problems such as high cost and poor storage stability.

[0004] Existing technologies, such as patents CN113334636A and CN1803435A, have proposed using waste cable plastic powder directly blended with asphalt for modification. However, these technologies still have the following shortcomings: cable materials containing a high proportion of cross-linked polyethylene (XLPE) or rubber have high melt viscosity, making them difficult to disperse uniformly; asphalt has poor compatibility with non-polar polymers, resulting in weak interfacial bonding; and the finished product is prone to segregation and has high shear energy consumption, making it difficult to achieve stable industrial applications. Therefore, it is necessary to develop a new modified asphalt system that can achieve high dispersibility and high compatibility through interfacial activation. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a polymer-modified asphalt derived from waste cables and its preparation method. One type of polymer-modified asphalt derived from waste cables, by weight, comprises the following components: 88-97 parts of base asphalt, 2-10 parts of waste cable-derived modifying components, 0.1-4 parts of compatibility-stabilizing and regulating components, and 0-2 parts of functional additives.

[0006] Furthermore, the functional additives include antioxidants, tackifying resins, and flame retardant additives; The antioxidant is one or more of hindered phenolic antioxidants, phosphite antioxidants, or thioester antioxidants, preferably one or more of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (AO-1010), octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (AO-1076), tris[2,4-di-tert-butylphenyl]phosphite (AO-168), and dilauryl thiodipropionate (DLTDP); The tackifying resin is one or more of C5 petroleum resin, C9 petroleum resin, C5 / C9 copolymer petroleum resin, and rosin resin; The flame retardant is one or more of aluminum hydroxide, magnesium hydroxide, ammonium polyphosphate, and expanded graphite.

[0007] Furthermore, when the antioxidant, tackifying resin and flame retardant are used simultaneously, their mass ratio is (1-3):(2-10):(2-12).

[0008] Furthermore, the compatibility stabilizing and regulating component is one or more of polyphosphoric acid (PPA), organomontmorillonite (OMMT), sulfur, and maleic anhydride-grafted polyethylene (PE-g-MA).

[0009] Furthermore, the maleic anhydride-grafted polyethylene (PE-g-MA) is preferably maleic anhydride-grafted linear low-density polyethylene with an average particle size of 0.5 mm-2.0 mm, preferably about 1.0 mm; a melt index (190℃, 2.16 kg) of 0.5-3.0 g / 10 min, preferably about 1.5 g / 10 min; a density of 0.90-0.95 g / cm³, preferably about 0.91 g / cm³; and a melting point of 115-130℃, preferably about 123℃.

[0010] Furthermore, the preparation method of the waste cable-derived modified component includes the following steps: (1) Separating conductors: mechanically stripping, crushing and sorting the waste cables to separate the metal conductors and non-metallic insulation components; (2) Purification and impurity removal: The non-metallic insulating components are subjected to magnetic separation, air separation and water washing to remove impurities, including metal residues, dust, fibers and silt. (3) Drying and refining: Dry the purified non-metallic insulating components to a moisture content of ≤0.5% and pulverize them to a particle size of 0.1mm-3mm; (4) Thermal shear chain scission activation: at 180-200℃, shear at 3000-8000 rpm for 10-60 min to partially break the XLPE chain and reduce the melt viscosity; (5) Chemical oxidative grafting treatment: Introduce 0.1-0.5 wt% organic peroxide to induce the cross-linked segments to generate polar functional groups; (6) Surface compatibilizer coating: Add 1-3 wt% reactive compatibilizer and shear at 150-180℃ for 15-30 min to form waste cable-derived modified components.

[0011] Furthermore, in step (3), the material is dried to a moisture content of ≤0.2% and pulverized to a particle size of 0.3mm-1.5mm.

[0012] Furthermore, in step (5), the organic peroxide is one or more of dicumyl peroxide (DCP), benzoyl peroxide (BPO), or maleic anhydride.

[0013] Furthermore, in step (6), the reactive compatibilizer is one or more of SEBS-g-MA, EVA-g-MA, and silane coupling agents.

[0014] Furthermore, SEBS-g-MA is preferably a linear maleic anhydride-grafted styrene-ethylene / butene-styrene block copolymer with a styrene content of 25-35 wt%, a maleic anhydride grafting amount of 1.4-2.0 wt%, a melt flow rate (230℃, 5kg) of 14-28 g / 10 min, and a Shore A hardness of 65-75.

[0015] Furthermore, EVA-g-MA is preferably a maleic anhydride-modified ethylene-vinyl acetate copolymer with a melt index (190°C, 2.16 kg) of 2-8 g / 10 min, preferably about 3.5 g / 10 min; a density of 0.93-0.96 g / cm³, preferably about 0.95 g / cm³; and a melting point of 65-85°C, preferably about 75°C.

[0016] A method for preparing polymer-modified asphalt derived from waste cables, characterized in that: the base asphalt is heated to 150-190℃ and the waste cable-derived modifying component is added in batches under constant temperature stirring conditions and stirred for 10-30 min; high shear dispersion is carried out at 3000-10000 rpm for 20-90 min; a compatibility stabilizing and regulating component is added and shearing is continued for 10-40 min; and degassing and homogenization are carried out for 10-30 min to obtain polymer-modified asphalt derived from waste cables.

[0017] Preferably, the degassing and homogenization methods are standing or low-speed stirring.

[0018] Furthermore, the high-shear dispersion rotation speed is 4000-8000 rpm, and the high-shear dispersion time is 30-60 min.

[0019] Furthermore, the base asphalt is filtered for impurities through a metal filter with a pore size of 0.6 mm before use.

[0020] Furthermore, the average particle size of the waste cable-derived modified component is 0.05 mm to 2.50 mm, preferably 0.20 mm to 1.20 mm.

[0021] The average particle size of the compatibility and stability control components is ≤2mm.

[0022] The average particle size of the antioxidant is ≤400 mesh.

[0023] Preferably, the antioxidant has an average particle size of 100-400 mesh.

[0024] The average particle size of the tackifying resin is ≤3mm.

[0025] Preferably, the average particle size of the tackifying resin is 0.2-3 mm.

[0026] The average particle size of the flame retardant additive is ≤50μm.

[0027] Preferably, the flame retardant additive has an average particle size of 5-50 μm.

[0028] The beneficial effects of this application are as follows: 1. The waste cable-derived modified components of this application form a reinforcing phase, which improves the high-temperature modulus and shear rheological resistance, and enhances the rutting resistance; the compatibility stabilizing control components improve the dispersion and interfacial bonding of waste cable-derived polymers in asphalt, reduce the risk of segregation, and improve storage stability.

[0029] 2. This application utilizes thermal-shear chain scission activation. Under a strong shear force field with high rotation speed and high temperature, some C-C bonds or weaker cross-linking bonds in the three-dimensional network cross-linked structure of XLPE undergo mechanical-thermal oxidative breakage. This essentially "shreds" the macromolecular network into plasticizable particles containing branches or shorter chain segments with a wider molecular weight distribution, thereby significantly reducing its melt viscosity and elasticity. The treated XLPE particles partially transform from "rubber elastomer" to "thermoplastic plastic," making them easier to deform, melt, and disperse during subsequent blending with asphalt, solving the problems of "difficulty in uniform dispersion" and "high shear energy consumption." This application improves the dispersion and compatibility of waste cables through thermal-shear-chemical composite activation treatment, thereby enhancing the high-temperature rutting resistance, low-temperature crack resistance, and storage stability of modified asphalt, achieving high-value utilization of waste cables.

[0030] 3. In the chemical oxidation and grafting steps, this application adds organic peroxides, which decompose at high temperature to generate free radicals that attack the polymer molecular chains (especially PE and XLPE) that have been activated during the thermal-shear process, and introduce active sites on their chains.

[0031] Introduction of polar functional groups: These active sites can undergo graft copolymerization reactions with monomers such as maleic anhydride (MAH), grafting carboxyl groups (-COOH) or anhydride groups onto the originally non-polar polyethylene molecular chains. These polar functional groups have stronger physical adsorption and chemical interaction forces with the polar components (such as asphaltenes and resins) abundant in asphalt.

[0032] This greatly enhances the surface polarity and reactivity of polymer particles, transforming them from "inert fillers" into "active modifiers," laying the foundation for forming a strong interface with asphalt.

[0033] 4. This application uses surface compatibilizer coating to ensure that the activated polymer particles can be stably dispersed in asphalt for a long time, preventing segregation of the finished product. The reactive compatibilizers used (such as SEBS-g-MA and EVA-g-MA) are all amphiphilic block copolymers. One end of their molecular structure (such as the MAH grafted part) contains polar groups, and the other end (such as the rubber segment of SEBS and the ethylene segment of EVA) has good compatibility with non-polar cable plastics (PE / XLPE).

[0034] In-situ coating and anchoring: Under heated shear conditions, the non-polar segments of the compatibilizer are tightly bonded to the surface of the cable plastic particles through molecular chain entanglement (physical anchoring), while their polar ends extend outwards. When these particles are added to asphalt, these extended polar ends can effectively integrate into the continuous asphalt phase, forming a strong steric hindrance and interfacial bonding layer.

[0035] A robust "transition layer" is constructed between the polymer particles and the asphalt, which not only further strengthens the interfacial bonding, but more importantly, prevents the migration, aggregation, and segregation of the modifier particles during asphalt storage and use, thus ensuring the storage stability and uniformity of the product.

[0036] 5. This application improves workability and reduces agglomeration through particle size control and pretreatment processes; the overall technical solution can realize the high-value utilization of solid waste, reduce modification costs and carbon emission risks; and the product is compatible with conventional asphalt mixture production processes and has engineering scalability. Attached Figure Description

[0037] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 Fluorescence micrograph of polymer-modified bitumen derived from waste cables obtained in Example 6; Figure 2 The images are SEM characterization diagrams, where image 1 corresponds to Example 4, image 2 corresponds to Example 5, image 3 corresponds to Example 6, image 4 corresponds to Example 7, image 5 corresponds to Example 8, image 6 corresponds to Example 11, image 7 corresponds to Example 12, image 8 corresponds to Example 13, image 9 corresponds to Example 1, image 10 corresponds to Example 4, and image 11 corresponds to the interface microstructure and two-phase fusion state diagram of Example 6. Detailed Implementation

[0038] Unless otherwise specified, the reagents and instruments used in the following examples are all commercially available products.

[0039] Example 1 A method for preparing polymer-modified bitumen derived from waste cables includes the following steps: Step A: Preparation of modified components derived from waste cables Conductor separation: The waste cable is mechanically stripped, crushed and sorted to separate the metallic conductor and non-metallic insulation components; Purification and impurity removal: The non-metallic insulating components are subjected to magnetic separation, air separation, and water washing to remove impurities; Drying and refining: Dry to a moisture content of 0.5% and pulverize to a particle size of 0.1 mm; Hot shear chain scission activation: at 180℃, shear at 3000 rpm for 60 min using a high shear mixer; Chemical oxidation grafting treatment: Add organic peroxide DCP, the amount of DCP added is 0.5 wt% of the waste cable after thermal shear chain scission activation; Surface compatibilizer coating: Add compatibilizer SEBS-g-MA, the amount of compatibilizer added is 1 wt% of the waste cable after thermal shear chain breaking activation, and shear at 150℃ for 20 min to form waste cable derived modified component; Understandably, SEBS-g-MA is a linear maleic anhydride-grafted styrene-ethylene / butene-styrene block copolymer with a styrene content of 30 wt%, a maleic anhydride grafting amount of 1.4-2.0 wt%, a melt flow rate (230℃, 5 kg) of 14-28 g / 10 min, and a Shore A hardness of approximately 71. To demonstrate the experimental results, this embodiment uses Kraton™ FG1901 G as the compatibilizer SEBS-g-MA; however, this embodiment is not limited to this product, and any product meeting the above performance requirements can be used.

[0040] Step B: Melt Shear Modification The base asphalt was heated to 150℃ and the waste cable-derived modified component was added in batches under constant temperature stirring conditions and stirred for 30 min; it was then dispersed at 3000 rpm under high shear for 90 min; the compatibility stabilizing and regulating component polyphosphoric acid (PPA) was added and shearing was continued for 10 min, and the mixture was allowed to stand for 10 min to obtain the waste cable-derived polymer-modified asphalt; the asphalt contained, by mass, 88 parts of base asphalt (70# road petroleum asphalt, filtered through a 0.6 mm metal screen to remove impurities before use), 2 parts of waste cable-derived modified component (average particle size of 0.05 mm), and 0.1 parts of compatibility stabilizing and regulating component.

[0041] Example 2 A method for preparing polymer-modified bitumen derived from waste cables includes the following steps: Step A: Preparation of modified components derived from waste cables Conductor separation: The waste cable is mechanically stripped, crushed and sorted to separate the metallic conductor and non-metallic insulation components; Purification and impurity removal: The non-metallic insulating components are subjected to magnetic separation, air separation, and water washing to remove impurities; Drying and refining: Dry to a moisture content of 0.3% and pulverize to a particle size of 3 mm; Hot shear chain scission activation: at 200℃, shear at 8000 rpm for 10 min using a high shear mixer; Chemical oxidation grafting treatment: Add organic peroxide BPO, the amount of BPO added is 0.1 wt% of the waste cable after thermal shear chain scission activation; Surface compatibilizer coating: Add compatibilizer EVA-g-MA, the amount of compatibilizer added is 3 wt% of the waste cable after hot shear chain breaking activation, and shear at 180℃ for 15 min to form waste cable derived modified component; Understandably, EVA-g-MA is a maleic anhydride-modified ethylene-vinyl acetate copolymer with a melt index (190℃, 2.16 kg) of 2-8 g / 10 min, a density of 0.93-0.96 g / cm³, and a melting point of 65-85℃. To demonstrate the experimental results, this embodiment uses the commercially available product OREVAC® 18211 as the compatibilizer. However, this embodiment is not limited to this product; any product meeting the above performance requirements can be used.

[0042] Step B: Melt Shear Modification The base asphalt was heated to 190℃ and the waste cable-derived modified component was added in batches under constant temperature stirring conditions and stirred for 10 min; it was then dispersed at 10000 rpm under high shear for 20 min; the compatibility stabilizing and regulating component, organomontmorillonite (OMMT, D50 of 20 μm), was added and sheared for another 40 min, and then allowed to stand for 30 min to obtain the waste cable-derived polymer-modified asphalt; the asphalt contained, by mass, 97 parts of base asphalt (70# road petroleum asphalt, filtered through a 0.6 mm metal screen to remove impurities before use), 10 parts of waste cable-derived modified component (average particle size of 2.5 mm), and 4 parts of compatibility stabilizing and regulating component.

[0043] Example 3 A method for preparing polymer-modified bitumen derived from waste cables includes the following steps: Step A: Preparation of modified components derived from waste cables Conductor separation: The waste cable is mechanically stripped, crushed and sorted to separate the metallic conductor and non-metallic insulation components; Purification and impurity removal: The non-metallic insulating components are subjected to magnetic separation, air separation, and water washing to remove impurities; Drying and refining: Dry to a moisture content of 0.2% and pulverize to a particle size of 0.3 mm; Hot shear chain scission activation: at 190℃, shear at 5000 rpm for 30 min using a high shear mixer; Chemical oxidation grafting treatment: Organic peroxide DCP was added as a free radical initiator, along with the polar grafting monomer maleic anhydride. The amount of DCP added was 0.1 wt% of the waste cable after thermal shear chain scission activation, and the amount of maleic anhydride added was 0.2 wt% of the waste cable after thermal shear chain scission activation. Surface compatibilizer coating: Add compatibilizer silane coupling agent γ-aminopropyltriethoxysilane (KH-550). The amount of compatibilizer added is 2 wt% of the waste cable after thermal shearing chain breaking activation. Shear at 160℃ for 30 min to form waste cable derived modified component. Step B: Melt Shear Modification The base asphalt was heated to 180℃ and the waste cable-derived modified component was added in batches under constant temperature stirring conditions and stirred for 10 min; it was then dispersed at 4000 rpm under high shear for 60 min; the compatibility stabilizing and regulating component PE-g-MA (average particle size 1.0 mm) was added, and shearing was continued for 20 min, followed by standing for 20 min to obtain the waste cable-derived polymer-modified asphalt; the asphalt consisted of 90 parts by mass of base asphalt (70# road petroleum asphalt, filtered through a 0.6 mm metal screen to remove impurities before use), 5 parts by mass of waste cable-derived modified component (average particle size 0.2 mm), and 1 part by mass of compatibility stabilizing and regulating component.

[0044] Understandably, maleic anhydride-grafted polyethylene (PE-g-MA) is maleic anhydride-grafted linear low-density polyethylene; its melt index (190℃, 2.16 kg) is 0.5–3.0 g / 10 min, its density is 0.90–0.95 g / cm³, and its melting point is 115–130℃. To demonstrate the experimental results, this embodiment uses commercially available PE-g-MA with the brand name OREVAC® 18302N; however, this embodiment is not limited to this product, and any product meeting the above performance requirements can be used.

[0045] Example 4 A method for preparing polymer-modified bitumen derived from waste cables includes the following steps: Step A: Preparation of modified components derived from waste cables Conductor separation: The waste cable is mechanically stripped, crushed and sorted to separate the metallic conductor and non-metallic insulation components; Purification and impurity removal: The non-metallic insulating components are subjected to magnetic separation, air separation, and water washing to remove impurities; Drying and refining: Dry to a moisture content of 0.2% and pulverize to a particle size of 1.5 mm; Hot shear chain scission activation: at 190℃, sheared at 6000 rpm for 40 min using a high shear mixer; Chemical oxidation grafting treatment: Add organic peroxide DCP and maleic anhydride. The amount of DCP added is 0.1 wt% of the waste cable after thermal shear chain scission activation, and the amount of maleic anhydride added is 0.2 wt% of the waste cable after thermal shear chain scission activation. Surface compatibilizer coating: Add compatibilizer SEBS-g-MA (same as in Example 1) and silane coupling agent γ-methacryloyloxypropyltrimethoxysilane (KH-570). The amount of SEBS-g-MA added is 1 wt% of the waste cable after thermal shear chain scission activation, and the amount of silane coupling agent added is 1 wt% of the waste cable after thermal shear chain scission activation. Shear at 160°C for 30 min to form waste cable derived modified component. Step B: Melt Shear Modification The base asphalt was heated to 160℃ and the waste cable-derived modified component was added in batches under constant temperature stirring conditions and stirred for 20 min; it was then dispersed at 8000 rpm under high shear for 30 min; the compatibility stabilizing and regulating component, organomontmorillonite (OMMT, D50 of 10 μm), was added and sheared for another 15 min, and then allowed to stand for 25 min to obtain the waste cable-derived polymer-modified asphalt; the asphalt consisted of 95 parts by mass of base asphalt (70# road petroleum asphalt, filtered through a 0.6 mm metal screen to remove impurities before use), 3 parts by mass of waste cable-derived modified component (average particle size of 1.2 mm), and 2 parts by mass of compatibility stabilizing and regulating component.

[0046] Example 5 Compared with Example 4, the only difference is the chemical oxidation grafting treatment: organic peroxides DCP and BPO are added. The amount of DCP added is 0.1 wt% of the waste cable after thermal shear chain scission activation, and the amount of BPO added is 0.2 wt% of the waste cable after thermal shear chain scission activation.

[0047] Example 6 Compared with Example 4, the only difference is the chemical oxidation grafting treatment: organic peroxides DCP, BPO, and maleic anhydride are added. The amount of DCP added is 0.1 wt% of the waste cable after thermal shear chain scission activation, the amount of BPO added is 0.1 wt% of the waste cable after thermal shear chain scission activation, and the amount of maleic anhydride added is 0.1 wt% of the waste cable after thermal shear chain scission activation.

[0048] Example 7 Compared with Example 4, the only difference is the surface compatibilizer coating: the compatibilizer EVA-g-MA (same as Example 2) and the silane coupling agent γ-glycidyl etheroxypropyltrimethoxysilane (KH-560) are added. The amount of EVA-g-MA added is 1 wt% of the waste cable after thermal shear chain scission activation, and the amount of silane coupling agent added is 1 wt% of the waste cable after thermal shear chain scission activation.

[0049] Example 8 The only difference compared to Example 4 is: The base asphalt was heated to 160℃ and the waste cable-derived modified component was added in batches under constant temperature stirring conditions and stirred for 20 min; it was then dispersed at 8000 rpm under high shear for 30 min; the compatibility stabilizing and regulating component, organomontmorillonite, was added and sheared for another 15 min; then the antioxidant AO-1076 was added and sheared for another 5 min; and the mixture was allowed to stand for 25 min to obtain the waste cable-derived polymer-modified asphalt; the asphalt contained, by mass, 95 parts base asphalt, 3 parts waste cable-derived modified component, 2 parts compatibility stabilizing and regulating component, and 0.2 parts antioxidant (average particle size of 200 mesh).

[0050] Example 9 The only difference compared to Example 4 is: The base asphalt was heated to 160℃ and the waste cable-derived modified component was added in batches under constant temperature stirring conditions and stirred for 20 min; it was then dispersed at 8000 rpm under high shear for 30 min; the compatibility stabilizing and regulating component, organomontmorillonite, was added and sheared for another 15 min; then the tackifying resin, C5 petroleum resin, was added and sheared for another 5 min; and the mixture was allowed to stand for 25 min to obtain the waste cable-derived polymer-modified asphalt; the asphalt contained, by mass, 95 parts base asphalt, 3 parts waste cable-derived modified component, 2 parts compatibility stabilizing and regulating component, and 1.0 part tackifying resin (average particle size 2 mm).

[0051] Example 10 Compared with Example 4, the only difference is that: the base asphalt was heated to 160°C and the waste cable-derived modified component was added in batches and stirred for 20 min under constant temperature stirring conditions; it was then dispersed at 8000 rpm under high shear for 30 min; the compatibility stabilizing and regulating component, organomontmorillonite, was added and sheared for another 15 min; then the flame retardant additive, aluminum hydroxide, was added and sheared for another 5 min; and the mixture was allowed to stand for 25 min to obtain the waste cable-derived polymer-modified asphalt; wherein, by mass parts, there were 95 parts of base asphalt, 3 parts of waste cable-derived modified component, 2 parts of compatibility stabilizing and regulating component, and 1.0 part of flame retardant additive (D50 is 30 μm).

[0052] Example 11 Compared with Example 4, the only difference is that: the base asphalt was heated to 160°C and the waste cable-derived modified component was added in batches under constant temperature stirring conditions and stirred for 20 min; high shear dispersion was carried out at 8000 rpm for 30 min; the compatibility stabilizing and regulating component, organomontmorillonite, was added and sheared for 15 min; then the antioxidant AO-1010 and the tackifying resin C5 / C9 copolymer petroleum resin were added. The C5 / C9 copolymer petroleum resin is a thermoplastic hydrocarbon tackifying resin with a softening point of 90-125°C, a number average molecular weight of 400-800 g / mol, and a weight average molecular weight of 700-1200 g / mol; the flame retardant additive, ammonium polyphosphate (APP), was added and sheared for 5 min. After standing for 25 minutes, the polymer-modified asphalt derived from waste cables was obtained; the asphalt consisted of 95 parts by mass, 3 parts by mass of waste cable-derived modified components, 2 parts by mass of compatibility stabilizing and regulating components, 0.2 parts by mass of antioxidant (AO-1010, 200 mesh), 0.8 parts by mass of tackifying resin (C5 / C9 copolymer petroleum resin, particle size 2 mm), and 1.0 part by mass of flame retardant additive (APP, D50 is 20 μm).

[0053] Example 12 Compared with Example 4, the difference is that the average particle size of the waste cable-derived modified component is 1.0 mm; and the average particle size D50 of organomontmorillonite (OMMT) is 50 μm.

[0054] Example 13 Compared with Example 11, the difference is that the average particle size of the antioxidant is 600 mesh and the average particle size of the tackifying resin is 5 mm.

[0055] Comparative Example 1 Compared with Example 4, the only difference is that the preparation method of waste cable-derived modified components lacks the steps of thermal shear chain scission activation, chemical oxidation grafting treatment, and surface compatibilizer coating.

[0056] Comparative Example 2 Compared with Example 4, the only difference is that the surface compatibilizer coating step is missing in the preparation method of waste cable-derived modified components.

[0057] Comparative Example 3 Compared with Example 4, the only difference is that the method for preparing waste cable-derived modified components lacks the thermal shear chain scission activation step.

[0058] Comparative Example 4 Compared to Example 4, the only difference is the lack of a compatible and stable regulatory component.

[0059] Comparative Example 5 Compared with Example 4, the only difference is in drying and refining: drying to a moisture content of 0.2% and pulverizing to a particle size of 5 mm.

[0060] Characterization: 1. To verify the uniform dispersion and interfacial bonding effect of the waste cable-derived modified components in asphalt, the samples of the examples and comparative examples were characterized by fluorescence microscopy and SEM: like Figure 1 The fluorescence micrographs, showing the size, distribution, and number of bright yellow particles, directly reflect the dispersion state of the modified polymer in asphalt. Figure 1 The medium-bright yellow particles are uniformly dispersed throughout the field of view, without large-area aggregation, localized enrichment "bright areas," or obvious polymer phase separation. The moderate number and uniform distribution density of particles indicate that the polymer has achieved good dispersion and swelling in the asphalt.

[0061] Figure 2(Figure 1) The matrix is ​​uniform overall with no obvious agglomeration. In Example 4, under the composite compatibilizer system, the modified component is well dispersed overall with only a very small amount of incompletely broken particles. The interfacial bonding is good, and the storage stability is excellent. (Figure 2) The oxidation grafting system corresponding to the dual initiator (DCP+BPO) compound in Example 5 significantly improves the grafting efficiency. The modified component is uniformly broken down and dispersed at the nanoscale. The two-phase interface is well integrated, and the storage stability is excellent. (Figure 3) The matrix is ​​uniform and dense. The modified component is uniformly dispersed as submicron particles, with no large particles, no pores, no agglomeration, and no obvious phase separation. The DCP+BPO + maleic anhydride ternary grafting system achieves the best interfacial compatibility between the modified component and asphalt. (Figure 4) Even after replacing it with the EVA-g-MA+KH560 composite compatibility system, it still maintains excellent dispersion. (Figure 5) and (Figure 6) show no obvious phase separation, indicating that the addition of functional additives did not negatively affect the compatibility of the modified system, and the dispersion effect remained excellent. (Figure 7) and (Figure 8) show no large particle agglomeration but small agglomerates, with a significant increase in the number of defects, indicating that changes in particle size affect overall compatibility. (Figure 9) shows the presence of ultra-large polymer agglomerates with rough particle edges, obvious indentation and tailing deformation in the surrounding asphalt matrix, and clear separation of the two-phase interface. This indicates the absence of thermal shear chain scission, oxidation grafting, and surface compatibility coating, suggesting complete incompatibility between the modified component and asphalt. The severe agglomeration and floating of polymers make this the sample with the worst morphology and extremely poor storage stability. (Figure 10) shows a hazy field of view filled with numerous nano / micron-sized particles, disrupting the matrix continuity and exhibiting obvious local particle enrichment. This indicates a lack of compatibility-stabilizing components, weak interfacial bonding between the modified component and asphalt, and a tendency for migration and segregation during high-temperature storage. (Figure 11) The two-phase interface has no clear boundary, exhibiting a continuous transitional fusion morphology. The polymer phase is fully impregnated and encapsulated by the asphalt phase, with no obvious gaps or phase separation. High magnification directly verifies the microscopic interface compatibility of Example 6, and the ternary grafting system enables the polymer and asphalt to form a stable interface structure.

[0062] 2. To address the issues of easy segregation and storage stability of the finished product, a segregation softening point difference test was conducted: Modified asphalt was poured into a separation tube and left to stand at 163℃ for 48 hours. Samples from the upper and lower parts were then taken to determine their softening points. The difference between the upper and lower softening points was used as an evaluation index for storage stability. The results are shown in Table 1 below.

[0063] Table 1. Softening point difference test results

[0064] The smaller the softening point difference, the lower the degree of polymer phase migration and segregation during high-temperature storage of modified asphalt, and the better its storage stability. In general engineering, a softening point difference of ≤2.5℃ for modified asphalt is considered to be of acceptable storage stability; ≤2.0℃ is considered excellent; and ≤1.5℃ indicates very good storage stability.

[0065] The softening point difference in all embodiments was less than 2.4°C, demonstrating that the polymer-modified bitumen derived from waste cables obtained in this application has good overall storage stability and no serious risk of segregation. Among them, Example 6 had the lowest softening point difference, indicating that the polymer and bitumen formed the most stable blend system, with extremely low risk of segregation and excellent storage stability.

[0066] The softening point difference of all comparative examples exceeding 2.5℃ indicates poor storage stability in the unoptimized system, leading to severe polymer buoyancy and segregation during high-temperature storage, completely failing to meet engineering requirements. Comparative Example 1's modified component was only simply broken down; the macromolecular chains remained intact, with no polar grafting or surface compatibility, making it completely incompatible with asphalt. The polymer exhibited severe agglomeration and buoyancy, with the most severe segregation. Data from Comparative Examples 1-3 demonstrate that the steps of thermal shear chain scission activation, chemical oxidation grafting, and compatibility coating significantly impact system compatibility. Comparative Example 4 lacks compatibility-stabilizing components, resulting in a lack of a network-like stable structure. The drying and refining steps of the non-metallic insulating component in Comparative Example 5 also affect system compatibility.

[0067] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0068] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A waste cable derived polymer modified bitumen, characterized in that, Based on mass parts, it consists of the following components: 88-97 parts of base bitumen, 2-10 parts of waste cable-derived modified components, 0.1-4 parts of compatibility stabilizing and regulating components, and 0-2 parts of functional additives.

2. The waste cable derived polymer modified asphalt of claim 1, wherein, The preparation method of the waste cable-derived modified component includes the following steps: (1) Separating conductors: mechanically stripping, crushing and sorting the waste cables to separate the metal conductors and non-metallic insulation components; (2) Purification and impurity removal: The non-metallic insulating components are subjected to magnetic separation, air separation and water washing to remove impurities; (3) Drying and refining: Dry the purified non-metallic insulating components to a moisture content of ≤0.5% and pulverize them to a particle size of 0.1mm-3mm; (4) Thermal shear chain scission activation: Shear at 3000-8000 rpm for 10-60 min at 180-200℃; (5) Chemical oxidative grafting treatment: Add 0.1-0.5 wt% organic peroxide; (6) Surface compatibilizer coating: Add 1-3 wt% of reactive compatibilizer and shear at 150-180℃ for 15-30 min to form waste cable-derived modified components.

3. The polymer-modified bitumen derived from waste cables according to claim 2, characterized in that, In step (3), the non-metallic insulating components are dried to a moisture content of ≤0.2% and pulverized to a particle size of 0.3mm-1.5mm.

4. The polymer-modified bitumen derived from waste cables according to claim 2, characterized in that, In step (5), the organic peroxide is one or more of dicumyl peroxide, benzoyl peroxide, and maleic anhydride.

5. The polymer-modified bitumen derived from waste cables according to claim 2, characterized in that, In step (6), the reactive compatibilizer is one or more of SEBS-g-MA, EVA-g-MA, and silane coupling agents.

6. The polymer-modified bitumen derived from waste cables according to claim 1, characterized in that, The functional additives include one or more of antioxidants, tackifying resins, and flame retardants. The antioxidant is one or more of hindered phenolic antioxidants, phosphite antioxidants, and thioester antioxidants; The tackifying resin is one or more of C5 petroleum resin, C9 petroleum resin, C5 / C9 copolymer petroleum resin, and rosin resin; The flame retardant is one or more of aluminum hydroxide, magnesium hydroxide, ammonium polyphosphate, and expanded graphite.

7. The polymer-modified bitumen derived from waste cables according to claim 6, characterized in that, The mass ratio of the antioxidant, tackifying resin, and flame retardant is (1-3):(2-10):(2-12).

8. The polymer-modified bitumen derived from waste cables according to claim 1, characterized in that, The compatibility stabilizing and regulating components are one or more of polyphosphoric acid, organomontmorillonite, sulfur, and maleic anhydride-grafted polyethylene.

9. The polymer-modified bitumen derived from waste cables according to claim 1, characterized in that, The particle size of the base asphalt is less than 0.6 mm; the particle size of the waste cable-derived modified component is 0.05 mm to 2.50 mm; and the particle size of the compatibility stabilizing control component is ≤2 mm.

10. A method for preparing polymer-modified bitumen derived from waste cables, characterized in that, The base asphalt is heated to 150-190℃ and the waste cable-derived modified component is added in batches under constant temperature stirring conditions and stirred for 10-30 min; it is then dispersed at high shear at 3000-10000 rpm for 20-90 min; the compatibility stabilizing and regulating component is added and shearing is continued for 10-40 min; degassing and homogenization are carried out for 10-30 min to obtain the waste cable-derived polymer-modified asphalt.

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