A molecular recovery type SBS modified asphalt regeneration agent and preparation method thereof

Abstract

The invention discloses a molecular recovery type SBS modified asphalt regeneration agent and a preparation method thereof, which is prepared from a toughness recovery agent, a rigidity recovery agent, a plasticizer, a reaction auxiliary agent, and a network former; the toughness recovery agent is a mixture of aliphatic cyclic ether and aliphatic enol in a mass ratio of 4:1, the rigidity recovery agent is an aromatic cyclic ether, the plasticizer is activated by biological heavy oil and waste rubber powder in a mass ratio of 5:1, the reaction auxiliary agent is a tertiary amine compound, and the network former is a polyvalent primary amine compound. The regeneration agent of the invention can not only restore the component composition of the aged asphalt, but also balance the rigid-flexible block ratio of the SBS molecule after regeneration through the toughness recovery agent and the rigidity recovery agent, solve the problem of significant decrease in the high temperature performance of the regenerated SBS, and use the network former to fully restore the cross-linked network structure of the SBS, thereby improving the comprehensive road performance of the regenerated SBS modified asphalt. The formula is unique, the performance is excellent, and the application prospect is broad.

Description

Technical Field

[0001] The invention belongs to the technical field of asphalt pavement materials, and in particular relates to a molecular recovery type SBS modified asphalt regeneration agent and a preparation method thereof. Background Art

[0002] Among the many asphalt modifiers currently available, the block structure and cross-linking properties of SBS give SBS modified asphalt excellent high and low temperature performance, making SBS modified asphalt widely favored in high-grade road construction. However, during service, with the influence of vehicle load and natural environment, SBS modified asphalt gradually ages and loses its road performance, seriously affecting the service quality of the road. Although the harm caused by the aging of SBS modified asphalt can be alleviated through road maintenance and reconstruction, its high cost and easy to produce a large amount of waste SBS modified asphalt mixtures. Obviously, based on the current demand for sustainable development of road resources, recycled SBS modified asphalt can not only recycle waste SBS modified asphalt mixtures, but also be economical and affordable, and belong to sustainable development technology.

[0003] During the aging process of SBS modified asphalt, not only the light components in the asphalt are continuously oxidized and polymerized, but also the cross-linked network is severely damaged as the SBS molecules degrade. Through regeneration technology, not only the component composition of asphalt is restored, but also the cross-linking of degraded SBS fragments to repair the internal network structure is the key to fully restore the high and low temperature performance of SBS modified asphalt. At present, research has found that the reaction of aliphatic epoxy compounds and aromatic isocyanate compounds with hydroxyl and carboxyl groups can repair the degraded SBS network structure. The low-temperature performance of SBS modified asphalt regenerated by aliphatic epoxy compounds has been greatly restored. The flexibility of the fatty chain meets the requirements of the regeneration ductility of the aged SBS modified asphalt, but it leads to the loss of some high-temperature performance. The degraded SBS fragments regenerated by aromatic isocyanate groups have a tighter cross-linked network, but due to the limitations of the cross-linked network and rigid groups, their low-temperature performance is weakened. At the same time, the toxicity of isocyanate compounds is relatively large, which greatly limits their promotion and application value. On this basis, the deficiencies of previous research can be improved by compounding aliphatic cyclic ethers with aromatic cyclic ethers through epoxy self-polymerization reaction, and at the same time, polyamines can be used to recreate a dense cross-linked network to improve the high and low temperature performance of recycled SBS modified asphalt, thereby fully restoring the road performance of SBS modified asphalt.

[0004] In terms of balanced regeneration of aged asphalt components, current research shows that bio-heavy oil has similar components and functions to aromatic oil, and can balance the components of aged asphalt, but it will greatly weaken the high-temperature performance of aged SBS modified asphalt. In order to compensate for the high-temperature performance degradation caused by bio-heavy oil regeneration on aged SBS modified asphalt, bio-heavy oil is used to preliminarily activate rubber powder, and the preliminarily activated rubber powder shows more significant high-temperature improvement ability, giving full play to the performance complementarity of the materials. At the same time, bio-heavy oil can be obtained through hydrothermal liquefaction of agricultural and forestry waste, and waste rubber powder is also produced by grinding tire waste. From the source of materials, both belong to the rational reuse of solid waste resources. Summary of the invention

[0005] The purpose of the present invention is to provide a molecular recovery type SBS modified asphalt regeneration agent and a preparation method thereof, which can fully restore the road performance of aged SBS modified asphalt. By improving the rational use of the regeneration agent, it can not only save road and oil resources, but also realize the recycling of solid waste.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A molecular recovery type SBS modified asphalt regeneration agent, the raw materials of which are calculated by weight: 4-8 parts of a toughness recovery agent, 0.5-1 parts of a rigidity recovery agent, 9-12 parts of a plasticizer regulator, 0.1 parts of a reaction auxiliary agent, and 0.1-0.2 parts of a network former; wherein the toughness recovery agent is prepared by mixing aliphatic cyclic ether and aliphatic enol in a mass ratio of 4:1, the rigidity recovery agent is an aromatic cyclic ether, the plasticizer regulator is prepared by activating biological heavy oil and waste rubber powder in a mass ratio of 5:1, the reaction auxiliary agent is a tertiary amine compound, and the network former is a polyvalent primary amine compound.

[0008] Further, the aliphatic cyclic ether is at least one of 1,3-bis(2,3-epoxypropoxy)-2,2-dimethylpropane and 2,2'-(1,2-ethylenedioxyformaldehyde) dioxirane, and the aliphatic enol is Z / E-1,4-butenediol. The aromatic cyclic ether is at least one of 1,3-benzenediol diglycidyl ether and 2,2-bis[4-(oxyglycidyl)phenyl]propane. The bio-heavy oil is a black viscous liquid obtained by hydrothermal liquefaction and cracking of agricultural and forestry waste. The waste rubber powder is a granular black powder obtained by grinding tire waste. The tertiary amine compound is N,N-dimethylbenzylamine. The polyamine compound is at least one of 3,6,9,12-tetraazatetradecane-1,14-diamine and 1,3-bis(aminomethyl)benzene.

[0009] The preparation method comprises the following steps: (1) mixing bio-heavy oil and waste rubber powder, activating at 140°C for 120 minutes at a stirring speed of 800 r / min, and naturally cooling to room temperature to obtain a plasticizer; (2) mixing a toughness recovery agent, a rigidity recovery agent, a reaction auxiliary agent, a network forming agent and a plasticizer, heating to 50-60°C, continuously stirring at a speed of 800-1000 r / min for 10-15 minutes, and naturally cooling to room temperature to obtain the molecular recovery type SBS modified asphalt regeneration agent.

[0010] Compared with the prior art, the beneficial effects of the present invention are:

[0011] (1) The aging of SBS modified asphalt is divided into two aspects: asphalt aging and SBS network structure degradation. The degradation of SBS molecules and the degree of destruction of the cross-linked network dominate the degree of performance degradation of SBS modified asphalt. The aliphatic cyclic ether in the toughness restoration agent contains epoxy groups, which can react with the hydroxyl and carboxyl groups in the degraded SBS molecular fragments under the catalytic ring-opening state to achieve the repair of the aged SBS molecules. At the same time, combined with the self-polymerization behavior of the epoxy groups, a cross-linked aliphatic long chain structure is formed, which can not only achieve the effect of preliminary repair of the SBS cross-linked network structure, but also make the repaired SBS molecular chain have excellent flexibility, making up for the loss of molecular chain flexibility caused by the degradation of carbon-carbon double bonds in SBS, and providing good low-temperature toughness for the regenerated SBS network structure.

[0012] (2) The polybutadiene in SBS contains carbon-carbon double bonds, which endow the SBS molecules with great flexibility. Z / E-1,4-butenediol also contains carbon-carbon double bonds. After the SBS molecules are repaired by aliphatic cyclic ethers, Z / E-1,4-butenediol is introduced into the initially repaired SBS molecules by utilizing the reactivity of epoxy groups and hydroxyl groups. Through the synergistic effect of carbon-carbon double bonds and aliphatic long chains, the degree of freedom and flexibility of SBS are further improved, achieving the toughness recovery effect of the regenerated SBS network structure, and jointly improving the low-temperature performance of SBS modified asphalt.

[0013] (3) The unique block structure of SBS makes SBS modified asphalt have excellent high-temperature and low-temperature properties. However, the SBS molecules regenerated by fatty compounds lack rigid groups, which leads to the serious weakening of the high-temperature performance of the regenerated SBS molecules. Through the self-polymerization reaction of epoxy groups, the benzene rings in the aromatic cyclic ethers are embedded in the SBS molecules to balance the block structure distribution of SBS, thereby realizing the rigidity recovery of the SBS molecular structure.

[0014] (4) The regeneration agent contains a large number of light components and low-viscosity reactive substances, which leads to a significant decrease in the high-temperature performance of the regenerated SBS modified asphalt. The cross-linked network structure of SBS is an important factor in improving the high-temperature performance of asphalt. Although the cross-linked network structure can be partially restored by cross-linking the PS segments of the fragments with epoxy groups, the cross-linking density still has room for improvement. The use of polyamines as cross-linking points, which are rich in multiple amino groups, can not only react with the carboxyl groups in the SBS fragments, but also undergo addition reactions with the epoxy groups. The high cross-linking property of the regenerated SBS molecular network can be restored by polyamines, further restoring the high-temperature performance of the SBS modified asphalt.

[0015] (5) The bio-heavy oil and waste rubber powder used in the present invention are both derived from solid waste and belong to solid waste utilization technology. The bio-heavy oil can be obtained by hydrothermal liquefaction and cracking of agricultural and forestry waste, and can restore the components of aged asphalt. The waste rubber powder is obtained by grinding waste tires and can improve the viscosity and toughness of recycled SBS modified asphalt. The efficacy of the waste rubber powder can be improved by activating the waste rubber powder with bio-heavy oil. The use of bio-heavy oil and waste rubber powder in SBS modified asphalt pavement regeneration technology belongs to the rational utilization of road waste and social waste. By recycling waste resources, the pollution and damage to the environment can be reduced, and the sustainable development of the highway industry can be achieved. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical scheme and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with embodiments. The embodiments listed in the present invention are only used to illustrate the present invention, not to limit the scope of the present invention, and any obvious modifications or changes made to the present invention do not depart from the spirit and scope of the present invention.

[0017] The aged SBS modified asphalt used in the following examples is obtained by using commercially available SBS modified asphalt (needle penetration at 25°C is 49 dmm, softening point is 70.2°C, elongation at 5°C is 35.2 cm, and viscosity is 1910 mPa·s) after aging in a rotary thin film oven (RTFOT, conditions: 163°C, 85 min; used to simulate the short-term aging of SBS modified asphalt during mixing, transportation, paving, and rolling) and aging in a pressure aging container (PAV, conditions: 100°C, 2.1 MPa, 20 h; used to simulate the long-term aging of SBS modified asphalt during pavement use). Its properties are as follows: needle penetration at 25°C is 31 dmm, softening point is 66.7°C, elongation at 5°C is 1.1 cm, and viscosity is 2140 mPa·s).

[0018] After preparing the SBS modified asphalt regeneration agent by the following embodiments, 100 parts of the aged SBS modified asphalt prepared above were weighed, heated in an oven at 180°C to a molten state, and then 15-22 parts of the prepared molecular recovery type SBS modified asphalt regeneration agent were added thereto, and then the aged SBS modified asphalt with the regeneration agent was continuously stirred for 1 hour at a temperature of 180°C and a rotation speed of 800r / min for regeneration, and finally, the regenerated SBS modified asphalt was obtained. The performance tests of the regenerated SBS modified asphalt involved in the following embodiments were all carried out in accordance with the current standard "Test Procedures for Asphalt and Asphalt Mixtures for Highway Engineering" (JTG E20-2011), and the above operations were not repeated in each embodiment, and the test results of the embodiments are listed in Table 1 for comparison.

[0019] Embodiment 1:

[0020] Weigh 10 parts of bio-heavy oil by weight and set aside;

[0021] Embodiment 2:

[0022] Weigh 7.5 parts of bio-heavy oil and 1.5 parts of waste rubber powder according to their mass proportions, add them into the same container and stir them preliminarily, and place the container in a 140°C oil bath at 800r / min for activation and development for 120min. After the activation is completed, take it out and cool it to room temperature for use;

[0023] Embodiment 3:

[0024] (1) Weigh 10 parts of bio-heavy oil and 2 parts of waste rubber powder according to their mass, add them into the same container and stir them preliminarily. At the same time, place the container in a 140°C oil bath and activate it at 800 r / min for 120 min. After activation, take it out and cool it to room temperature for use;

[0025] (2) Weigh 0.1 parts of 3,6,9,12-tetraazatetradecyl-1,14-diamine and 0.1 parts of 1,3-di(aminomethyl)benzene according to their mass fractions, add them to the container containing the preliminary mixture, and set aside;

[0026] (3) The premix was heated to 50°C and stirred for 15 minutes at 900 r / min using an electric stirrer. After stirring, the mixture was cooled to room temperature to obtain an SBS modified asphalt regeneration agent.

[0027] Embodiment 4:

[0028] (1) Weigh 10 parts of bio-heavy oil and 2 parts of waste rubber powder according to their mass, add them into the same container and stir them preliminarily. At the same time, place the container in a 140°C oil bath and activate it at 800 r / min for 120 min. After activation, take it out and cool it to room temperature for use;

[0029] (2) Weigh 6.4 parts of 1,3-bis(2,3-epoxypropoxy)-2,2-dimethylpropane, 1.6 parts of Z / E-1,4-butene diol, and 0.1 parts of N,N-dimethylbenzylamine according to their mass fractions, add them to the container containing the preliminary mixture, and set aside;

[0030] (3) The premix was heated to 50°C and stirred for 10 min at 800 r / min using an electric stirrer. After stirring, the mixture was cooled to room temperature to obtain an SBS modified asphalt regeneration agent.

[0031] Embodiment 5:

[0032] (1) Weigh 10 parts of bio-heavy oil and 2 parts of waste rubber powder according to their mass, add them into the same container and stir them preliminarily. At the same time, place the container in a 140°C oil bath and activate it at 800 r / min for 120 min. After activation, take it out and cool it to room temperature for use;

[0033] (2) Weigh 4.8 parts of 1,3-bis(2,3-epoxypropoxy)-2,2-dimethylpropane, 1.2 parts of Z / E-1,4-butene diol, 0.1 parts of N,N-dimethylbenzylamine, and 0.1 parts of 3,6,9,12-tetraazatetradecyl-1,14-diamine according to their mass fractions, add them to the container containing the preliminary mixture, and set aside;

[0034] (3) The premix was heated to 60°C and stirred for 12 minutes at a speed of 1000 r / min using an electric stirrer. After stirring, the mixture was cooled to room temperature to obtain an SBS modified asphalt regeneration agent.

[0035] Embodiment 6:

[0036] (1) Weigh 8 parts of bio-heavy oil and 1.6 parts of waste rubber powder according to their mass, add them into the same container and stir them preliminarily. At the same time, place the container in a 140°C oil bath and activate it at 800 r / min for 120 min. After activation, take it out and cool it to room temperature for use;

[0037] (2) Weigh 5 parts of 1,3-bis(2,3-epoxypropoxy)-2,2-dimethylpropane, 1.4 parts of 2,2'-(1,2-ethylenedioxyformaldehyde) dioxirane, 1.6 parts of Z / E-1,4-butene diol, 1 part of 1,3-benzenediol diglycidyl ether, 0.1 part of N,N-dimethylbenzylamine, and 0.1 part of 3,6,9,12-tetraazatetradecyl-1,14-diamine according to mass fraction, add them to the container containing the preliminary mixture and set aside;

[0038] (3) The premix was heated to 50°C and stirred for 15 minutes at 800 r / min using an electric stirrer. After stirring, the mixture was cooled to room temperature to obtain an SBS modified asphalt regeneration agent.

[0039] Embodiment 7:

[0040] (1) Weigh 8 parts of bio-heavy oil and 1.6 parts of waste rubber powder according to their mass, add them into the same container and stir them preliminarily. At the same time, place the container in a 140°C oil bath and activate it at 800 r / min for 120 min. After activation, take it out and cool it to room temperature for use;

[0041] (2) Weigh 5 parts of 1,3-bis(2,3-epoxypropoxy)-2,2-dimethylpropane, 1.4 parts of 2,2'-(1,2-ethylenedioxyformaldehyde) dioxirane, 1 part of 1,3-benzenediol diglycidyl ether, 0.1 part of N,N-dimethylbenzylamine, and 0.1 part of 3,6,9,12-tetraazatetradecyl-1,14-diamine according to their mass fractions, add them to the container containing the preliminary mixture, and set aside;

[0042] (3) The premix was heated to 50°C and stirred for 10 min at 900 r / min using an electric stirrer. After stirring, the mixture was cooled to room temperature to obtain an SBS modified asphalt regeneration agent.

[0043] Embodiment 8:

[0044] (1) Weigh 10 parts of bio-heavy oil and 2 parts of waste rubber powder according to their mass, add them into the same container and stir them preliminarily. At the same time, place the container in a 140°C oil bath and activate it at 800 r / min for 120 min. After activation, take it out and cool it to room temperature for use;

[0045] (2) Weigh 5 parts of 1,3-bis(2,3-epoxypropoxy)-2,2-dimethylpropane, 1.4 parts of 2,2'-(1,2-ethylenedioxyformaldehyde) dioxirane, 1.6 parts of Z / E-1,4-butene diol, 0.5 parts of 1,3-benzenediol diglycidyl ether, 0.5 parts of 2,2-bis[4-(oxyglycidyl)phenyl]propane, 0.1 parts of N,N-dimethylbenzylamine, 0.1 parts of 3,6,9,12-tetraazatetradecyl-1,14-diamine, and 0.1 parts of 1,3-bis(aminomethyl)benzene according to mass fraction, add them to the container containing the preliminary mixture and set aside;

[0046] (3) The premix was heated to 60°C and stirred for 15 minutes at 200 r / min using an electric stirrer. After stirring, the mixture was cooled to room temperature to obtain an SBS modified asphalt regeneration agent.

[0047] Embodiment 9:

[0048] (1) Weigh 8 parts of bio-heavy oil and 1.6 parts of waste rubber powder according to their mass, add them into the same container and stir them preliminarily. At the same time, place the container in a 140°C oil bath and activate it at 800 r / min for 120 min. After activation, take it out and cool it to room temperature for use;

[0049] (2) Weigh 6.4 parts of 1,3-bis(2,3-epoxypropoxy)-2,2-dimethylpropane, 1.6 parts of Z / E-1,4-butenediol, 0.25 parts of 1,3-benzenediol diglycidyl ether, 0.25 parts of 2,2-bis[4-(oxyglycidyl)phenyl]propane, 0.1 parts of N,N-dimethylbenzylamine, and 0.1 parts of 1,3-bis(aminomethyl)benzene according to their mass fractions, add them to the container containing the preliminary mixture, and set aside;

[0050] (3) The premix was heated to 60°C and stirred for 15 minutes at 800 r / min using an electric stirrer. After stirring, the mixture was cooled to room temperature to obtain an SBS modified asphalt regeneration agent.

[0051]

[0052] It can be seen from the examples that bio-heavy oil can soften aged asphalt, increase the penetration and elongation of aged asphalt, and reduce the softening point and viscosity. At the same time, the initial activated waste rubber powder alleviates the serious weakening of high-temperature performance. Under the joint action of the two, the basic properties of asphalt are restored. The toughness recovery agent restored the low-temperature performance of SBS modified asphalt. Through the synergistic regeneration of aliphatic cyclic ethers and Z / E-1,4-butenediol, the ductility of aged SBS modified asphalt at 5°C was restored to 20cm or even more than 30cm. The rigidity recovery agent improved the block ratio of the regenerated molecular chain, and the regeneration performance of SBS modified asphalt tended to be balanced. Both high and low temperature performances could be restored to the road performance requirements of ID type SBS modified asphalt. The network forming agent increased the crosslinking degree of the regenerated SBS network, greatly improving the high-temperature performance of the regenerated SBS modified asphalt, greatly improving the softening point of the regenerated SBS modified asphalt, and making the regenerated high-temperature performance more significant. Through the joint action of flexible regenerated chains, rigid groups and cross-linked networks, the various properties of SBS were significantly improved. The components of the regenerator complemented each other during the regeneration process and synergistically improved the road performance of the regenerated SBS modified asphalt.

[0053] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A molecular recovery type SBS modified asphalt regeneration agent, characterized in that: The raw materials are calculated by weight as follows: 4-8 parts of toughness recovery agent, 0.5-1 parts of rigidity recovery agent, 9-12 parts of plasticizer regulator, 0.1 parts of reaction auxiliary agent, and 0.1-0.2 parts of network forming agent; wherein the toughness recovery agent is prepared by mixing aliphatic cyclic ether and aliphatic enol in a mass ratio of 4:1, the rigidity recovery agent is an aromatic cyclic ether, the plasticizer regulator is prepared by activating biological heavy oil and waste rubber powder in a mass ratio of 5:1, the reaction auxiliary agent is a tertiary amine compound, and the network forming agent is a polyvalent primary amine compound; The aliphatic cyclic ether is at least one of 1,3-bis(2,3-epoxypropoxy)-2,2-dimethylpropane and 2,2'-(1,2-ethylenedioxyformaldehyde)dioxirane, and the aliphatic enol is Z / E-1,4-butenediol; The aromatic cyclic ether is at least one of 1,3-benzenediol diglycidyl ether and 2,2-bis[4-(oxyglycidyl)phenyl]propane; The tertiary amine compound is N,N-dimethylbenzylamine; The polyvalent primary amine compound is at least one of 3,6,9,12-tetraazatetradecyl-1,14-diamine and 1,3-di(aminomethyl)benzene.

2. The molecular recovery type SBS modified asphalt regeneration agent according to claim 1, characterized in that: The biological heavy oil is a black viscous liquid obtained by hydrothermal liquefaction and cracking of agricultural and forestry waste.

3. The molecular recovery type SBS modified asphalt regeneration agent according to claim 1, characterized in that: The waste rubber powder is a granular black powder obtained by grinding tire waste.

4. A method for preparing the molecular recovery type SBS modified asphalt regeneration agent according to any one of claims 1 to 3, characterized in that: The following steps are involved: (1) mixing the bio-heavy oil and the waste rubber powder, activating the mixture at 140°C for 120 min at a stirring speed of 800 r / min, and naturally cooling the mixture to room temperature to obtain a plasticizer; (2) The toughness recovery agent, the rigidity recovery agent, the reaction auxiliary agent, the network forming agent and the plasticizing regulator are mixed, heated to 50-60° C., stirred continuously at a speed of 800-1000 r / min for 10-15 min, and naturally cooled to room temperature to obtain the molecular recovery type SBS modified asphalt regeneration agent.

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