A high modulus recycled polymer modified asphalt, asphalt mixture, asphalt modifier and preparation method and application thereof

Abstract

The present invention discloses a high modulus recycled polymer asphalt modifier, which is mainly prepared from the following components in parts by weight: 30 to 55 parts of RET resin, 40 to 60 parts of recycled polymer polyolefin plastics, 3 to 5 parts of DCT interface treatment agent, and 2 to 5 parts of HEUR rheology modifier. Preferably, the RET resin is a copolymer of ethylene-butyl acrylate-glycidyl methacrylate, and the recycled polyolefin plastic is a mixture of one or both of PP or PE. Based on the same inventive concept, the present invention also provides a method for preparing a high modulus recycled polymer asphalt modifier. In addition, the present invention also provides a high modulus recycled polymer modified asphalt, a modified asphalt mixture and a method for using the same. The present invention improves the interfacial adhesion of asphalt aggregates and improves the shear and impact resistance of asphalt mixtures by introducing high-activity, high-modulus polymer modifiers, interface treatment agents and rheology modifiers.

Description

Technical Field

[0001] The present invention relates to the field of recycled asphalt modification, and in particular to a high modulus recycled polymer modified asphalt, an asphalt mixture, an asphalt modifier, and a preparation method and application thereof. Background Art

[0002] my country's expressways began to be built in 1989, with a design life of 10-15 years. During the service life, asphalt pavement is subject to heavy traffic, natural climate, alternating high and low temperatures, and ultraviolet rays, resulting in defects such as cracking, subsidence, rutting, and congestion, which makes it difficult for the pavement to meet traffic requirements and seriously affects driving safety and comfort. Therefore, the pavement needs to be renovated. Every year, asphalt pavements that are undergoing major or medium repairs need to be renovated. Every year, more than 10 million tons of asphalt waste is generated from renovated asphalt pavements. How to dispose of this waste is a problem that the industry must face. At the same time, the large amount of asphalt and gravel materials required for paving asphalt concrete pavements also brings huge resource pressure.

[0003] Recycled asphalt mixture refers to the mixture made by digging up, recycling, crushing and screening old asphalt pavement, and then mixing it with regeneration agent, new asphalt material, new aggregate, etc. in a certain proportion. The whole process of making it meet certain road performance and re-paving it on the road surface is called asphalt pavement recycling. The recycling of asphalt pavement can save a lot of raw materials such as asphalt, sand and gravel, save project investment, and is conducive to the treatment of waste and protection of the environment. Therefore, it has significant economic benefits, social benefits and environmental benefits.

[0004] Asphalt regeneration polymer technology is used to achieve the reuse of asphalt concrete waste. The existing asphalt regeneration polymer technology improves the coating of aged asphalt by replenishing the lost oil in the aged asphalt, and improves the material indicators obtained by heating and mixing the mixture. However, this recycled polymer asphalt has defects such as insufficient asphalt modulus, insufficient viscosity, and insufficient grip because the adhesion ability of the aged asphalt to the aggregate has not been restored. Therefore, it often causes looseness, sinking and other diseases within a few years after paving the road surface.

[0005] Therefore, the prior art needs to be improved urgently. Summary of the invention

[0006] The purpose of the present invention is to address the defects of the prior art in asphalt, such as insufficient modulus, insufficient viscosity, and insufficient grip, and to provide a high modulus recycled polymer asphalt modifier, a method for preparing the asphalt modifier, and modified asphalt and asphalt mixture prepared by the modifier, as well as the application of the asphalt modifier, modified asphalt, and asphalt mixture. The present invention improves the shear and impact resistance of the asphalt mixture by introducing a high-activity, high-modulus polymer modifier, an interface treatment agent, and a rheology modifier to improve the asphalt aggregate interface adhesion. The performance meets the requirements of high modulus modified asphalt.

[0007] The technical solution of the present invention is achieved in this way:

[0008] A high modulus recycled polymer asphalt modifier is mainly prepared from the following components in parts by weight: 30-55 parts of RET resin, 40-60 parts of recycled polymer polyolefin plastic, 3-5 parts of DCT interface treatment agent, and 2-5 parts of HEUR rheology modifier. Of course, other additives can be added appropriately depending on the specific application environment. In the present invention, RET resin refers to a copolymer of ethylene-butyl acrylate-glycidyl methacrylate, which is a reactive elastomer terpolymer. DCT interface treatment agent is a functional polyamine mixture. HEUR rheology modifier refers to an ethylene oxide modified polyurethane copolymer.

[0009] The recycled polymer polyolefin plastic in the present invention has an aliphatic long chain structure and a high molecular weight, plays a skeleton support role in the asphalt mixture to increase the modulus, and improves the shear resistance and impact resistance of the asphalt mixture. my country produces a large amount of polyolefin recycled plastics every year, with abundant raw materials and low prices, but this type of polyolefin plastic has poor compatibility with asphalt due to its weak polarity, and is prone to segregation and stratification when used alone. RET resin is a reactive elastomer terpolymer synthesized from ethylene, butyl acrylate, and glycidyl methacrylate as monomers. After the reactive elastomer terpolymer composed of it is mixed with asphalt, its ester substances are more easily dispersed in the asphalt phase due to their polarity similar to asphalt, effectively reducing the surface tension of the recycled asphalt, improving the stretching ability of the recycled polyolefin plastic macromolecular chain, and better dispersing in the recycled asphalt petroleum system, giving the high modulus recycled polymer asphalt modifier of the present invention good storage stability and dispersibility; and RET resin has good ductility, elongation at break and elasticity, which can improve the fatigue resistance and high temperature rutting resistance of the recycled asphalt. At the same time, RET resin has highly active epoxy groups. As a low molecular weight dispersant, HEUR rheology modifier can not only improve the fluidity of recycled asphalt, but also has good compatibility with recycled asphalt, reduces the surface tension of recycled asphalt and reduces segregation, and can also bring better coating to recycled asphalt. At the same time, HEUR rheology modifier also has highly active epoxy groups. DCT interface treatment agent can improve the interface adhesion and anchoring force during the preparation of asphalt mixture. Preferably, the DCT interface treatment agent includes diethylenetriamine, triethylenetetramine, tetraethylenepentamine and N-hydroxyethylpiperazine. The polyamines in the DCT interface treatment agent provide a strong alkaline environment at a high temperature of about 180°C. The highly active epoxy groups in the RET resin and the highly active epoxy groups in the HEUR react with the amino groups in the triethylenetetramine, tetraethylenepentamine, and N-hydroxyethylpiperazine in the DCT interface treatment agent to form an effective three-dimensional network reinforcement structure through the bridge effect of the DCT interface treatment agent, so that the RET resin, the HEUR rheology modifier, and the DCT interface treatment agent can form an effective three-dimensional network reinforcement structure, which can improve the viscoelasticity and toughness of the regenerated modified asphalt, and at the same time make the high modulus regenerated polymer asphalt modifier of the present invention, and the asphalt mixture is more stable and less prone to phase separation. In addition, the active epoxy groups in the RET resin and the active epoxy groups in the HEUR can also react with the free carboxylic acid groups and phenolic hydroxyl groups in the asphalt molecules, which can effectively improve the interfacial adhesion of the asphalt mixture. Under the synergistic effect of several substances, the regenerated asphalt is given a high modulus and good stability and dispersibility, while having the advantages of energy saving and emission reduction. The above-mentioned various ingredients in certain amounts cooperate with each other to be fully compatible with the recycled asphalt, give full play to the performance of each component, and finally make the material form a high modulus recycled polymer asphalt modifier.

[0010] As described above, the high modulus recycled polymer asphalt modifier, the RET resin is a copolymer of ethylene-butyl acrylate-glycidyl methacrylate, and has a melt index of 8-10 g / 10 min at 190° C. and a load of 2.16 kg. With this performance, the ester substances of the RET resin can significantly reduce the surface tension of the recycled asphalt due to the similar polarity to asphalt, and improve the compatibility and dispersibility of polyolefin plastics in the asphalt mixture. The RET resin also has a toughening effect and exhibits high viscosity and high elasticity.

[0011] Preferably, the RET resin is a reactive elastomer terpolymer produced by Dow Chemical Company of the United States, which is a reactive elastomer terpolymer synthesized from ethylene, acrylate, and glycidyl methacrylate as monomers. More preferably, the RET resin is ELVALOY TM 5170, its melting point is 82°C, its melt index is 10g / 10min at 190°C and load is 2.16KG, and its density is 0.95g / cm 3 .

[0012] A high modulus recycled polymer asphalt modifier as described above, wherein the recycled polyolefin plastic is one of PP or PE or a mixture of the two. In this scheme, the recycled polyolefin plastic has an aliphatic long chain structure and a high molecular weight, plays a skeleton support role in the asphalt mixture to increase the modulus, and improves the shear resistance and impact resistance of the asphalt mixture. Preferably, the recycled polyolefin plastic adopts a green recycled material product purchased from Hunan Zhongsu New Material Technology Co., Ltd.

[0013] As described above, the high modulus recycled polymer asphalt modifier, the DCT interface treatment agent is a small molecule polyethylene amine mixture, the degree of polymerization is 2 to 5, and the reaction activity is relatively high at this degree of polymerization.

[0014] A high modulus recycled polymer asphalt modifier as described above, the DCT interface treatment agent includes diethylenetriamine, triethylenetetramine, tetraethylenepentamine and N-hydroxyethylpiperazine, wherein diethylenetriamine is 10 parts, triethylenetetramine is 50-90 parts, tetraethylenepentamine is 2-10 parts, and N-hydroxyethylpiperazine is 5 parts. The DCT interface treatment agent with the above performance plays the role of interface treatment agent and curing agent in the present invention, so that RET resin, DCT interface treatment agent, and HEUR rheology modifier form a three-dimensional hugging structure, thereby improving the interface adhesion and anchoring force. Preferably, the DCT interface treatment agent adopts the Amine DCT product purchased from Dow.

[0015] The high modulus recycled polymer asphalt modifier as described above, the HEUR rheology modifier is an ethylene oxide modified polyurethane copolymer emulsion, which can not only improve the fluidity of the recycled asphalt, but also has good compatibility with the recycled asphalt, reduces the surface tension of the recycled asphalt and reduces segregation, and can also bring better coating properties to the recycled asphalt. Preferably, the HEUR rheology modifier is Acrysol RM12W purchased from Rohm and Haas Company.

[0016] Based on the same inventive concept, the present invention provides a method for preparing a high modulus recycled polymer asphalt modifier, comprising the following steps:

[0017] Step 1: RET resin and recycled polymer polyolefin plastic are fully mixed in a high-speed mixer according to a set ratio to obtain material 1; preferably, in step 1, the mixing time is 20 to 50 minutes, and the mixing speed is 400 to 600 rpm; more preferably, in step 1, the mixing time is 30 minutes, and the mixing speed is 500 rpm;

[0018] Step 2: adding HEUR rheology modifier to material 1 in a set ratio and mixing evenly in a high-speed mixer to obtain material 2; preferably, in step 2, the mixing time is 30 to 50 minutes, and the mixing speed is 500 to 600 rpm; more preferably, in step 2, the mixing time is 30 minutes, and the mixing speed is 500 rpm;

[0019] Step 3: Add the DCT interface treatment agent to material 2 in a set ratio and mix them evenly in a high-speed mixer to obtain material 3; preferably, in step 3, the mixing time is 30 to 60 minutes and the mixing speed is 500 to 600 rpm; more preferably, in step 3, the mixing time is 30 minutes and the mixing speed is 500 rpm;

[0020] Step 4: Add material 3 in step 3 from the main feed port to a parallel twin-screw extruder for extrusion and granulation, and use water-cooled pelletizing. After drying, a high modulus recycled polymer asphalt modifier is obtained. Preferably, the pelletizing temperature is 150°C to 160°C, and the screw speed is 200 to 400rpm. More preferably, the pelletizing temperature is 160°C and the screw speed is 300rpm. Preferably, the drying is specifically: after water-cooled pelletizing, the obtained pellets are heated to 40 to 60°C for cyclone drying. More preferably, the drying is specifically: after water-cooled pelletizing, the obtained pellets are heated to 40°C for cyclone drying. Under this condition, the drying speed is fast, the drying is uniform, and there is no local overheating.

[0021] Based on the same inventive concept, the present invention also provides a high modulus recycled polymer modified asphalt, the raw materials of which include a high modulus recycled polymer asphalt modifier as described above or a high modulus recycled polymer asphalt modifier prepared by the preparation method as described above.

[0022] In the high modulus recycled polymer modified asphalt as described above, the mass fraction of the high modulus recycled polymer asphalt modifier in the modified asphalt is 8.5% to 15%. Preferably, the mass fraction of the high modulus recycled polymer asphalt modifier in the modified asphalt is 12%.

[0023] Based on the same inventive concept, the present invention also provides a high modulus recycled polymer modified asphalt mixture, the raw materials of which include a high modulus recycled polymer asphalt modifier as described above or a high modulus recycled polymer modified asphalt as described above.

[0024] Based on the same inventive concept, the present invention also provides the use of a high modulus recycled polymer asphalt modifier as described above, or a high modulus recycled polymer modified asphalt as described above, or a high modulus recycled polymer modified asphalt mixture as described above as a road building material in road maintenance or road construction.

[0025] The beneficial effects of the present invention are:

[0026] 1. The present invention provides a high modulus recycled polymer asphalt modifier, which is mainly prepared from the following components: RET resin, recycled polyolefin plastics, DCT interface treatment agent, and HEUR rheology modifier. RET resin is a reactive elastomer terpolymer with ethylene, acrylate, and glycidyl methacrylate as monomers. Since polyolefins are non-polar substances, and asphaltene contains complex aromatic ring substances with strong polarity, its dispersibility and compatibility are poor. The ester substances of RET resin are more easily dispersed in the asphalt phase due to their similar polarity to asphalt, thus reducing the surface tension of recycled asphalt and effectively improving the compatibility and dispersibility of recycled asphalt with recycled polyolefin plastics. The use of recycled polyolefins not only effectively improves the modulus, high temperature sensitivity, and fatigue resistance of recycled asphalt, but also has environmental and economic advantages.

[0027] 2. A high modulus recycled polymer asphalt modifier provided by the present invention has the following characteristics: the ring-opening reaction of the highly active epoxy groups in RET resin, the epoxy groups in HEUR rheology modifier, and the amine groups in DCT interfacial modifier under alkaline conditions forms a three-dimensional reinforced structure, which can effectively improve the fastening force between the recycled asphalt and the modifier and the new asphalt. The RET resin in the modifier of the present invention not only plays the role of a polymer alloy compatibilizer, but also has a toughening effect; since the RET resin reduces the surface tension of the asphalt, the DCT interfacial modifier and the HEUR rheology modifier work together to produce a stable asphalt mixture, thereby improving the dispersibility and stability of the asphalt; the recycled polyolefin plastic continuous phase effectively improves the modulus. At the same time, the epoxy groups in RET resin and the epoxy groups in HEUR rheology modifier can also react with the free carboxylic acid groups and phenolic hydroxyl groups in the asphalt molecules, effectively improving the interfacial adhesion of the asphalt mixture. The above certain amounts of various components cooperate with each other and are fully compatible with asphalt, giving full play to the performance of each component, thereby improving the compatibility, stability, toughness and high modulus between the recycled asphalt modifier and the recycled modified asphalt.

[0028] 3. The asphalt modifier RET resin developed by the present invention, the hydroxyl groups generated by the ring-opening reaction of the active epoxy groups in the HEUR rheology modifier and the amino groups in the DCT interface treatment agent, and the highly polar carbamate groups contained in the HEUR rheology modifier have good affinity with the inorganic salts on the surface of aggregate stones, improve the interface affinity between aggregate stones and asphalt, fully mix with aggregates, and have better dispersibility and coating. The penetration ability of asphalt molecules is enhanced, the asphalt mixture is tightly wrapped with aggregate stones, the void ratio is reduced, and the water damage resistance of the recycled modified asphalt mixture is improved. DETAILED DESCRIPTION

[0029] The following will combine the contents in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0031] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0032] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0033] In the following Examples 1 to 5, the RET resin is ELVALOY TM 5170 product, its melting point is 82℃, at 190℃, under load of 2.16KG, the melt index is 10g / 10min, and the density is 0.95g / cm 3 ; Recycled polyolefin plastics are green recycled materials purchased from Hunan Zhongsu New Material Technology Co., Ltd., with a density of 1.07g / cm 3 The ash content is 4.5%, the molding shrinkage is 1.0-2.5%, and the molding temperature is 160-220°C; the DCT interface treatment agent uses Amine DCT purchased from Dow; the HEUR rheology modifier uses Acrysol RM12W purchased from Rohm and Haas, which is a transparent to milky white liquid and a reactive non-ionic surfactant.

[0034] Embodiment 1:

[0035] A high modulus recycled polymer asphalt modifier is mainly prepared from the following components in parts by weight: 30 parts of RET resin, 60 parts of recycled polyolefin plastics, 5 parts of DCT interface treatment agent, and 5 parts of HEUR rheology modifier.

[0036] The preparation method of the high modulus recycled polymer asphalt modifier is as follows:

[0037] Step 1: 30 parts of RET resin and 60 parts of recycled polyolefin plastics were mixed in a high-speed mixer for 30 minutes at a speed of 500 rpm to obtain material 1;

[0038] Step 2: Add 5 parts of HEUR rheology modifier to material 1 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 2;

[0039] Step 3, add 5 parts of DCT interface treatment agent to material 2 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 3;

[0040] Step 4: Add material 3 in step 3 from the main feeding port to a parallel twin-screw extruder for granulation. The granulation temperature is 160°C, the screw speed is 300rpm, and water-cooled pelletizing is used. The obtained pellets are heated to 40°C and cyclone dried. After drying, a high modulus recycled polymer asphalt modifier is obtained.

[0041] Embodiment 2:

[0042] A high modulus recycled polymer asphalt modifier is mainly prepared from the following components in parts by weight: 55 parts of RET resin, 40 parts of recycled polyolefin plastics, 3 parts of DCT interface treatment agent, and 2 parts of HEUR rheology modifier.

[0043] The preparation method of the high modulus recycled polymer asphalt modifier is as follows:

[0044] Step 1: 55 parts of RET resin and 40 parts of recycled polyolefin plastic were mixed in a high-speed mixer for 30 minutes at a speed of 500 rpm to obtain material 1;

[0045] Step 2: Add 2 parts of HEUR rheology modifier to material 1 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 2;

[0046] Step 3, add 3 parts of DCT interface treatment agent to material 2 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 3;

[0047] Step 4: Add material 3 in step 3 from the main feeding port to a parallel twin-screw extruder for granulation. The granulation temperature is 160°C, the screw speed is 300rpm, and water-cooled pelletizing is used. The obtained pellets are heated to 40°C and cyclone dried. After drying, a high modulus recycled polymer asphalt modifier is obtained.

[0048] Embodiment 3:

[0049] A high modulus recycled polymer asphalt modifier is mainly prepared from the following components in parts by weight: 40 parts of RET resin, 50 parts of recycled polyolefin plastics, 5 parts of DCT interface treatment agent, and 5 parts of HEUR rheology modifier.

[0050] The preparation method of the high modulus recycled polymer asphalt modifier is as follows:

[0051] Step 1: 40 parts of RET resin and 50 parts of recycled polyolefin plastic were mixed in a high-speed mixer for 30 minutes at a speed of 500 rpm to obtain material 1;

[0052] Step 2: Add 5 parts of HEUR rheology modifier to material 1 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 2;

[0053] Step 3, add 5 parts of DCT interface treatment agent to material 2 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 3;

[0054] Step 4: Add material 3 in step 3 from the main feeding port to a parallel twin-screw extruder for granulation. The granulation temperature is 160°C, the screw speed is 300rpm, and water-cooled pelletizing is used. The obtained pellets are heated to 40°C and cyclone dried. After drying, a high modulus recycled polymer asphalt modifier is obtained.

[0055] Embodiment 4:

[0056] A high modulus recycled polymer asphalt modifier is mainly prepared from the following components in parts by weight: 43 parts of RET resin, 50 parts of recycled polyolefin plastics, 5 parts of DCT interface treatment agent, and 2 parts of HEUR rheology modifier.

[0057] The preparation method of the high modulus recycled polymer asphalt modifier is as follows:

[0058] Step 1: 43 parts of RET resin and 50 parts of recycled polyolefin plastic were mixed in a high-speed mixer for 30 minutes at a speed of 500 rpm to obtain material 1;

[0059] Step 2: Add 2 parts of HEUR rheology modifier to material 1 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 2;

[0060] Step 3, add 5 parts of DCT interface treatment agent to material 2 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 3;

[0061] Step 4: Add material 3 in step 3 from the main feeding port to a parallel twin-screw extruder for granulation. The granulation temperature is 160°C, the screw speed is 300rpm, and water-cooled pelletizing is used. The obtained pellets are heated to 40°C and cyclone dried. After drying, a high modulus recycled polymer asphalt modifier is obtained.

[0062] Embodiment 5:

[0063] A high modulus recycled polymer asphalt modifier is mainly prepared from the following components in parts by weight: 42 parts of RET resin, 50 parts of recycled polyolefin plastics, 3 parts of DCT interface treatment agent, and 5 parts of HEUR rheology modifier.

[0064] The preparation method of the high modulus recycled polymer asphalt modifier is as follows:

[0065] Step 1: 42 parts of RET resin and 50 parts of recycled polyolefin plastic were mixed in a high-speed mixer for 30 minutes at a speed of 500 rpm to obtain material 1;

[0066] Step 2: Add 5 parts of HEUR rheology modifier to material 1 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 2;

[0067] Step 3, add 3 parts of DCT interface treatment agent to material 2 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 3;

[0068] Step 4: Add material 3 in step 3 from the main feeding port to a parallel twin-screw extruder for granulation. The granulation temperature is 160°C, the screw speed is 300rpm, and water-cooled pelletizing is used. The obtained pellets are heated to 40°C and cyclone dried. After drying, a high modulus recycled polymer asphalt modifier is obtained.

[0069] Comparative Example 1:

[0070] An asphalt modifier is mainly prepared from the following components in parts by weight: 30 parts of POE resin, 60 parts of recycled polyolefin plastic, 5 parts of DCT interface treatment agent, and 5 parts of HEUR rheology modifier. Among them, POE uses LG Chemical's POE ethylene-1-butene copolymer LC168, which is an elastic composite material with a melt index of 5g / 10min under 2.16kg and 190°C. The same recycled polyolefin plastic, DCT interface treatment agent, and HEUR rheology modifier as in Example 1 are used.

[0071] The preparation method of the asphalt modifier is as follows:

[0072] Step 1: 30 parts of POE resin and 60 parts of recycled polyolefin plastic were mixed in a high-speed mixer for 30 minutes at a speed of 500 rpm to obtain material 1;

[0073] Step 2: Add 5 parts of HEUR rheology modifier to material 1 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 2;

[0074] Step 3, add 5 parts of DCT interface treatment agent to material 2 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 3;

[0075] Step 4: Add material 3 in step 3 from the main feeding port to a parallel twin-screw extruder for granulation. The granulation temperature is 160°C, the screw speed is 300rpm, and water-cooled pelletizing is used. The obtained pellets are heated to 40°C and cyclone dried. After drying, a high modulus recycled polymer asphalt modifier is obtained.

[0076] Comparative Example 2:

[0077] An asphalt modifier is mainly prepared from the following components by weight: 55 parts of RET resin, 40 parts of recycled polyolefin plastics, 3 parts of anti-stripping agent, and 2 parts of HEUR rheology modifier. The anti-stripping agent is Shijiazhuang Junlong Chemical JW-AS1 product with a density of 0.95-1.00 g / cm 3 , using the same RET resin, recycled polyolefin plastic, and HEUR rheology modifier as in Example 2.

[0078] The preparation method of the asphalt modifier is as follows:

[0079] Step 1: 55 parts of RET resin and 40 parts of recycled polyolefin plastic were mixed in a high-speed mixer for 30 minutes at a speed of 500 rpm to obtain material 1;

[0080] Step 2: Add 2 parts of HEUR rheology modifier to material 1 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 2;

[0081] Step 3, add 3 parts of anti-stripping agent to material 2 in a high-speed mixer and mix evenly at a mixing speed of 500 rpm for 30 min to obtain material 3;

[0082] Step 4: Add material 3 in step 3 from the main feeding port to a parallel twin-screw extruder for granulation. The granulation temperature is 160°C, the screw speed is 300rpm, and water-cooled pelletizing is used. The obtained pellets are heated to 40°C and cyclone dried. After drying, a high modulus recycled polymer asphalt modifier is obtained.

[0083] Comparative Example 3:

[0084] An asphalt modifier is mainly prepared from the following components in parts by weight: 40 parts of RET resin, 50 parts of recycled polyolefin plastics, 5 parts of DCT interface treatment agent, and 5 parts of dispersant, wherein the dispersant is a product of model LD-1110 produced by Lida Chemical. The same RET resin, recycled polyolefin plastics, and DCT interface treatment agent as in Example 3 are used.

[0085] The preparation method of the asphalt modifier is as follows:

[0086] Step 1: 40 parts of RET resin and 50 parts of recycled polyolefin plastic were mixed in a high-speed mixer for 30 minutes at a speed of 500 rpm to obtain material 1;

[0087] Step 2: Add 5 parts of dispersant to material 1 and mix evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 2;

[0088] Step 3, add 5 parts of DCT interface treatment agent to material 2 and mix them evenly in a high-speed mixer at a mixing speed of 500 rpm for 30 min to obtain material 3;

[0089] Step 4: Add material 3 in step 3 from the main feeding port to a parallel twin-screw extruder for granulation. The granulation temperature is 160°C, the screw speed is 300rpm, and water-cooled pelletizing is used. The obtained pellets are heated to 40°C and cyclone dried. After drying, a high modulus recycled polymer asphalt modifier is obtained.

[0090] Comparative Example 4:

[0091] Asphalt modifier is a commercially available high modulus asphalt additive, black particles, density 0.92 ~ 1.0g / cm 3 , tensile strength 25~30MPa, elongation at break 8~12%.

[0092] The high modulus recycled polymer asphalt modifier of the present invention and the asphalt modifier of the comparative example are tested and evaluated by the test performance index of the prepared modified recycled asphalt. Preferably, the mass fraction of the added modifier in the prepared modified recycled asphalt is 12%. The recycled asphalt comes from Shandong Road and Bridge Group Co., Ltd., and the test results of various indicators are: needle penetration (0.1mm): 55, elongation 10℃ (cm): 15, softening point (℃): 48, solubility (%): 99.2, dynamic viscosity 60℃ Pa·s: 174.

[0093] According to the standard "JTGE20-2011 Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering", various relevant indicators of asphalt mixtures are tested.

[0094] The preparation method of modified recycled asphalt is as follows:

[0095] In a 1.2-liter stainless steel straight-cylinder reactor with an insulation interlayer, add 880 grams of recycled asphalt and preheat to 170°C. Add 120 grams of modifier within 30 minutes, stir at 600 rpm until completely melted, and develop at 170°C for 2 hours. The modified recycled asphalt is prepared.

[0096] In order to characterize the performance of the high modulus recycled polymer asphalt modifiers prepared in Examples 1 to 5 and compare them with the modifiers of Comparative Examples 1 to 3, the modified recycled asphalt and asphalt mixtures prepared using different modifiers of Examples 1 to 5 and Comparative Examples 1 to 4 were respectively subjected to performance tests. Specific test evaluation results are shown in Tables 1 and 2.

[0097] Table 1 Evaluation results of recycled modified asphalt

[0098]

[0099]

[0100] According to the performance data of the regenerated modified asphalt of Examples 1 to 5 and Comparative Examples 1 to 3 in Table 1, in Comparative Example 1, compared with Example 1, the softening point, kinematic viscosity, tackiness, and storage stability of the modified regenerated asphalt obtained by replacing the RET resin with the POE resin are significantly worse. RET is a reactive elastomer terpolymer, and its highly active epoxy group participates in the ring-opening reaction. The ester substances of RET resin are more easily dispersed in the asphalt phase due to their similar polarity to asphalt, which reduces the surface tension of the regenerated asphalt. The role of RET resin as a reactive compatibilizer in the present invention is well reflected. Comparative Example 2 Compared with Example 2, the DCT interface treatment agent is replaced by an anti-stripping agent, and the kinematic viscosity of the modified regenerated asphalt obtained is significantly reduced. Among them, the DCT interface treatment agent, as a reactive interface treatment agent, not only provides an alkaline environment to play a catalytic role, but also participates in the cross-linking reaction to effectively improve the interfacial adhesion of the regenerated asphalt. Comparative Example 3 Compared with Example 3, the HEUR rheology modifier is replaced by a non-reactive dispersant, and the obtained modified recycled asphalt has a higher penetration, and the viscosity and kinematic viscosity are reduced. HEUR, as a reactive dispersant, participates in cross-linking, which plays a positive role in the penetration, viscosity and kinematic viscosity of the modified recycled asphalt. Comparative Example 4 Compared with Examples 1 to 5, the active epoxy group reaction system of RET resin and HEUR rheology modifier with DCT interface treatment agent as a bridge in the embodiment effectively improves the cross-linking degree of the polymer. At the same time, the active epoxy group reacts with the amino group, phenolic hydroxyl group and the like in the asphalt molecule to improve the dispersibility of the polymer modifier, reduce the surface tension of the recycled asphalt, reduce segregation, provide support for the dispersion of recycled polyolefin plastics, and effectively improve the modulus of the recycled asphalt. The elastic recovery performance, viscosity and storage stability of the asphalt mixture prepared using the highly active reactive modifier of the present invention are significantly improved compared with the comparative example.

[0101] The standard sample of recycled asphalt mixture was prepared and tested according to GB / T 36143-2018 High modulus anti-fatigue asphalt mixture for roads, in which the amount of modified recycled asphalt binder was 5.2%.

[0102] Table 2 Evaluation results of recycled modified asphalt mixture

[0103]

[0104] According to Table 2, the void ratio of the asphalt mixtures using the recycled high modulus modifier in Examples 1 to 5 is smaller than that in Comparative Examples 1 to 4, which proves that the reactive formula of the present invention has certain advantages in terms of coating and penetration. It can also be clearly seen that the stiffness modulus and dynamic stability performance of Examples 1 to 5 are greatly improved compared with Comparative Examples 1 to 4, and the residual strength ratio is improved to a certain extent. This shows that the recycled asphalt mixture prepared using the modifier of the present invention has significant water damage resistance and rutting resistance.

[0105] The test results of Tables 1 and 2 of Examples 1 to 5 and Comparative Examples 1 to 4 show that the asphalt mixture added with the high modulus recycled polymer asphalt modifier of the present invention has high elasticity, viscosity, stability and water damage resistance and effectively improves the rutting problem. In other words, the four components of RET resin, recycled polyolefin plastic, DCT interface treatment agent and HEUR rheology modifier must be used in combination to achieve the overall comprehensive performance of the material. Replacing similar components cannot achieve the excellent effect of the present invention.

[0106] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high modulus recycled polymer asphalt modifier, characterized in that: It is mainly prepared from the following components in parts by weight: 30-55 parts of RET resin, 40-60 parts of recycled polymer polyolefin plastic, 3-5 parts of DCT interface treatment agent, and 2-5 parts of HEUR rheology modifier; the preparation method of the high modulus recycled polymer asphalt modifier comprises the following steps: Step 1: RET resin and recycled polymer polyolefin plastic are fully mixed according to a set ratio to obtain material 1; Step 2: Add HEUR rheology modifier to material 1 according to a set ratio and mix evenly to obtain material 2; Step 3, adding DCT interface treatment agent to material 2 according to a set ratio and mixing evenly to obtain material 3; the DCT interface treatment agent is a small molecule polyethylene amine mixture, and its degree of polymerization is 2 to 5; Step 4: Add the material 3 in step 3 from the main feed port into the parallel twin-screw extruder for extrusion and granulation, use water cooling to cut the pellets, and after drying, obtain a high modulus recycled polymer asphalt modifier.

2. A high modulus recycled polymer asphalt modifier according to claim 1, characterized in that: The RET resin is a copolymer of ethylene-butyl acrylate-glycidyl methacrylate, and has a melt index of 8-10 g / 10 min at 190° C. and a load of 2.16 kg.

3. A high modulus recycled polymer asphalt modifier according to claim 1, characterized in that: The recycled polyolefin plastic is one of PP or PE or a mixture of the two.

4. A high modulus recycled polymer modified asphalt, characterized in that: The raw material comprises a high modulus recycled polymer asphalt modifier according to any one of claims 1 to 3.

5. The high modulus recycled polymer modified asphalt according to claim 4, characterized in that: The mass fraction of the high modulus recycled polymer asphalt modifier in the modified asphalt is 8.5% to 15%.

6. A high modulus recycled polymer modified asphalt mixture, characterized in that: The raw material comprises a high modulus recycled polymer asphalt modifier as described in any one of claims 1 to 3.

7. Use of a high modulus recycled polymer asphalt modifier as described in any one of claims 1 to 3, or a high modulus recycled polymer modified asphalt as described in claim 4, or a high modulus recycled polymer modified asphalt mixture as described in claim 6 as a road building material in road maintenance or road construction.

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