A double-regenerated SBS modified asphalt and preparation method thereof

Abstract

The present invention provides a double-regenerated SBS modified asphalt and a preparation method thereof. The double-regenerated SBS modified asphalt of the present invention comprises aged SBS modified asphalt, bisphenol A novolac epoxy resin, epoxy linseed oil, and maleic anhydride; the bisphenol A novolac epoxy resin undergoes a ring-opening reaction under the catalytic action of maleic anhydride, reacts with the carbonyl and carboxyl groups at the ends of the aged SBS molecular fragments, and connects them to complete the recovery of the SBS network structure; the epoxy linseed oil having a softening effect and good permeability and thermal stability can supplement the light components volatilized by aging of the asphalt, and at the same time promotes the penetration of the bisphenol A novolac epoxy resin in the aged asphalt, thereby improving the low-temperature performance of the aged SBS asphalt. The preparation method of the double-regenerated SBS modified asphalt of the present invention can efficiently restore the use performance of the aged SBS modified asphalt, and has important application value.

Description

Technical Field

[0001] The invention relates to the field of road materials, and in particular to a double-regenerated SBS modified asphalt and a preparation method thereof. Background Art

[0002] At present, the amount of old asphalt pavement materials (RAP) generated by major and medium-sized repair projects of trunk roads in my country alone reaches nearly 200 million tons each year, of which styrene-butadiene-styrene block copolymer (SBS) modified asphalt mixture accounts for a certain proportion. As a typical thermoplastic elastomer, SBS is widely used in asphalt pavements. Because SBS polymers can form a three-dimensional network structure in asphalt, they can improve the high and low temperature stability of asphalt. However, during the paving and use of SBS modified asphalt pavements, due to the coupling effects of light, heat, oxygen, moisture, etc., the light components of asphalt will volatilize and small molecules will be transformed into large molecules, making the asphalt hard and brittle. At the same time, the SBS molecular structure will be damaged and broken into SBS molecular fragments, causing it to lose its excellent modification effect. It is worth noting that due to the limitations of regeneration technology, it is difficult to achieve efficient regeneration of SBS modified asphalt, which will lead to serious waste of resources and environmental pollution.

[0003] The most commonly used regeneration method is to use light oils such as aromatics and saturated oils to adjust the components of aged asphalt, reduce asphalt agglomeration, and restore the performance of asphalt. However, this traditional regeneration method cannot achieve efficient regeneration of aged SBS modified asphalt. Because the SBS molecules in the aged SBS modified asphalt cannot be effectively repaired, the good viscoelastic properties of the asphalt given by the SBS modifier are difficult to restore. Although researchers at home and abroad can achieve the regeneration of aged SBS modified asphalt by adding new SBS modifiers or new SBS modified asphalt, there will be problems such as poor compatibility of the regenerated asphalt and inability to reuse degraded SBS.

[0004] In view of the shortcomings of the current regeneration technology of aged SBS modified asphalt, it is urgent to conduct dual regeneration research on aged asphalt and degraded SBS molecules. Summary of the invention

[0005] In view of this, the present invention proposes a double-regenerated SBS modified asphalt and a preparation method thereof to solve or partially solve the technical problems existing in the prior art.

[0006] In a first aspect, the present invention provides a double-regenerated SBS modified asphalt, comprising the following raw materials in parts by weight:

[0007] 100 parts of aged SBS modified asphalt, 1-3 parts of bisphenol A novolac epoxy resin, 4-8 parts of epoxy linseed oil, and 0.1-0.3 parts of maleic anhydride.

[0008] Preferably, the double-regenerated SBS modified asphalt, the aged SBS modified asphalt has a softening point of 78.1°C, an elongation of 12 mm at 5°C, and a needle penetration of 21.3 dmm at 25°C; wherein 1 dmm = 0.1 mm.

[0009] Preferably, in the double-regenerated SBS modified asphalt, the bisphenol A novolac epoxy resin has an epoxy equivalent of 185 to 195 g / mol, a softening point of 10 to 28° C., and an average molecular weight of 3100 to 7000.

[0010] Preferably, in the double-regenerated SBS modified asphalt, the molecular weight of the epoxy linseed oil is 750-900.

[0011] In a second aspect, the present invention further provides a method for preparing the dual-regenerated SBS modified asphalt, comprising the following steps:

[0012] The aged SBS modified asphalt is heated to a molten state;

[0013] Bisphenol A type novolac epoxy resin and maleic anhydride are added to the molten aged SBS modified asphalt, and after stirring, epoxy linseed oil is added, and the stirring is continued to obtain the double regenerated SBS modified asphalt.

[0014] Preferably, in the method for preparing the double-regenerated SBS modified asphalt, the aged SBS modified asphalt is heated at 140-150° C. to a molten state.

[0015] Preferably, in the preparation method of the double regenerated SBS modified asphalt, bisphenol A novolac epoxy resin and maleic anhydride are added to the aged SBS modified asphalt in a molten state, stirred at a stirring speed of 800 to 1200 rpm for 10 to 20 minutes, and then epoxy linseed oil is added, and stirring is continued for 10 to 20 minutes to obtain the double regenerated SBS modified asphalt.

[0016] Preferably, the preparation method of the double regenerated SBS modified asphalt is to add bisphenol A type novolac epoxy resin and maleic anhydride to the aged SBS modified asphalt in a molten state, stir, then add epoxy linseed oil, continue to stir, and then place at 130-140°C for 20-40 minutes to obtain the double regenerated SBS modified asphalt.

[0017] A double-regenerated SBS modified asphalt and a preparation method thereof of the present invention have the following beneficial effects compared to the prior art: the double-regenerated SBS modified asphalt of the present invention comprises aged SBS modified asphalt, bisphenol A type novolac epoxy resin, epoxy linseed oil, and maleic anhydride; the bisphenol A type novolac epoxy resin undergoes a ring-opening reaction under the catalytic action of maleic anhydride, reacts with the carbonyl and carboxyl groups at the ends of the aged SBS molecular fragments, and connects them to complete the recovery of the SBS network structure; the epoxy linseed oil having a softening effect and good permeability and thermal stability can supplement the light components volatilized by aging of the asphalt, and at the same time promotes the penetration of the bisphenol A type novolac epoxy resin in the aged asphalt, thereby improving the low-temperature performance of the aged SBS asphalt. The preparation method of the double-regenerated SBS modified asphalt of the present invention can efficiently restore the original performance of the aged SBS modified asphalt, and has great application value. DETAILED DESCRIPTION

[0018] The following will be combined with 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.

[0019] The present application embodiment provides a double-regenerated SBS modified asphalt, comprising the following raw materials in parts by weight:

[0020] 100 parts of aged SBS modified asphalt, 1-3 parts of bisphenol A novolac epoxy resin, 4-8 parts of epoxy linseed oil, and 0.1-0.3 parts of maleic anhydride.

[0021] It should be noted that the aged SBS modified asphalt in the embodiment of the present application is obtained by accelerating the aging test of SBS modified asphalt in a pressure aging container, the aging temperature is 100°C, the pressure is 2.1MPa, and the duration is 20h; wherein, the SBS modified asphalt original sample is obtained by physical shearing and stirring, and its softening point is 65.8°C, the elongation at 5°C is 268mm, and the needle penetration at 25°C is 42.0dmm; specifically, under the condition that the oil bath temperature is 175°C, the heat-softened base asphalt is heated to a molten state, the SBS modifier is added, and the base asphalt and SBS mixture are sheared using an intermittent high-speed shear emulsifier at a shear rate of 4000r / min, and the shear time is 40m in; then use a paddle stirrer to stir it evenly at a speed of 500r / min for 100min to complete the preparation of SBS modified asphalt; the above-mentioned base asphalt is 70# asphalt, and the SBS polymer is produced by Baling Petrochemical Co., Ltd.; the bisphenol A novolac epoxy resin (EPN) used in this application is produced by Shenzhen Huite Chemical Co., Ltd., and its chemical name is linear phenolic polyglycidyl ether, a light brown viscous liquid, which is a heat-resistant epoxy resin; maleic anhydride catalyst is produced by Sinopharm Chemical Reagent Co., Ltd. and is colorless crystals or white crystalline powder; Epoxy linseed oil is purchased from Zhejiang Xingbang Polymer Materials Co., Ltd., and the specific model is American ACSEpoxol The molecular weight is 750-900, and it is a yellow oily substance. The bisphenol A novolac epoxy resin in this application undergoes a ring-opening reaction under the catalysis of maleic anhydride, reacts with the carbonyl and carboxyl groups at the ends of the aged SBS molecular fragments, and connects them to complete the recovery of the SBS network structure. The epoxy linseed oil with a softening effect and good permeability and thermal stability can replenish the light components volatilized by aging asphalt, and at the same time promote the penetration of bisphenol A novolac epoxy resin in aged asphalt, thereby improving the low-temperature performance of aged SBS asphalt. The double regeneration method can efficiently restore the original performance of aged SBS modified asphalt and has great application value.

[0022] In some embodiments, the aged SBS modified asphalt has a softening point of 78.1°C, an elongation of 12 mm at 5°C, and a needle penetration of 21.3 dmm at 25°C; wherein 1 dmm = 0.1 mm.

[0023] In some embodiments, the bisphenol A novolac epoxy resin has an epoxy equivalent of 185 to 195 g / mol, a softening point of 10 to 28° C., and an average molecular weight of 3100 to 7000.

[0024] In some embodiments, the molecular weight of the epoxidized linseed oil is 750-900.

[0025] Based on the same inventive concept, the present application also provides a method for preparing the above-mentioned double-regenerated SBS modified asphalt, comprising the following steps:

[0026] S1. heating the aged SBS modified asphalt to a molten state;

[0027] S2. Add bisphenol A type novolac epoxy resin and maleic anhydride to the aged SBS modified asphalt in a molten state, stir, then add epoxy linseed oil, and continue stirring to obtain double regenerated SBS modified asphalt.

[0028] The preparation method of the double-regenerated SBS modified asphalt of the present application has two aspects of regeneration effect. First, the bisphenol A novolac epoxy resin undergoes a ring-opening reaction under the action of maleic anhydride catalyst, reacts with the carbonyl and carboxyl groups at the ends of the aged SBS molecular fragments, and connects them to restore the SBS network structure; second, epoxy linseed oil with a softening effect and good permeability and thermal stability is used to supplement the light components of the asphalt that are volatilized due to aging, while promoting the penetration of bisphenol A novolac epoxy resin in the aged asphalt, thereby improving the low-temperature performance of the aged SBS asphalt. This double regeneration method can efficiently restore the original performance of the aged SBS modified asphalt and has great application value.

[0029] In some embodiments, the aged SBS modified asphalt is heated at 140-150° C. to a molten state.

[0030] In some embodiments, bisphenol A novolac epoxy resin and maleic anhydride are added to molten aged SBS modified asphalt, stirred at a stirring speed of 800-1200 rpm for 10-20 minutes, and then epoxy linseed oil is added and stirred for 10-20 minutes to obtain double regenerated SBS modified asphalt.

[0031] In some embodiments, bisphenol A type novolac epoxy resin and maleic anhydride are added to molten aged SBS modified asphalt, stirred, and then epoxy linseed oil is added. After continued stirring, the mixture is placed at 130-140° C. for 20-40 minutes to obtain double regenerated SBS modified asphalt.

[0032] The following further describes the dual regenerated SBS modified asphalt and its preparation method of the present application with specific examples. This section further describes the content of the present invention in conjunction with specific examples, but should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the examples are conventional means known to those skilled in the art. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0033] Example 1

[0034] The embodiment of the present application provides a double regenerated SBS modified asphalt, comprising the following components in parts by weight: 100 parts of aged SBS modified asphalt, 2 parts of bisphenol A novolac epoxy resin, 6 parts of epoxy linseed oil, and 0.2 parts of maleic anhydride;

[0035] Among them, the softening point of aged SBS modified asphalt is 78.1℃, the ductility at 5℃ is 12mm, and the needle penetration at 25℃ is 21.3dmm, where 1dmm=0.1mm;

[0036] Bisphenol A novolac epoxy resin was produced by Shenzhen Huite Chemical Co., Ltd.;

[0037] Epoxidized linseed oil was purchased from Zhejiang Xingbang Polymer Materials Co., Ltd. The specific model is ACS Epoxol Molecular weight is 750-900;

[0038] Maleic anhydride was produced by Sinopharm Chemical Reagent Co., Ltd.;

[0039] Aged SBS modified asphalt is obtained by subjecting SBS modified asphalt to an accelerated aging test in a pressure aging container; the aging temperature is 100°C, the pressure is 2.1 MPa, and the time is 20 h. 。

[0040] The preparation method of SBS modified asphalt is as follows: under the condition that the temperature of the oil bath pot is 175°C, the heat-softened base asphalt is heated to a molten state, an SBS polymer modifier is added, and an intermittent high-speed shear emulsifier is used to shear the base asphalt and SBS mixture at a shear rate of 4000r / min for 40min; then a paddle agitator is used to stir it evenly at a speed of 500r / min for 100min, and the preparation of SBS modified asphalt is completed; wherein, the base asphalt is 70# asphalt, and the SBS polymer is produced by Baling Petrochemical Co., Ltd.

[0041] The present application also provides a method for preparing the above-mentioned double-regenerated SBS modified asphalt, comprising the following steps:

[0042] S1. According to the above weight portions, the aged SBS modified asphalt was heated at 145°C to a molten state, and then bisphenol A novolac epoxy resin and maleic anhydride catalyst were added respectively at a stirring speed of 1000 rpm, and the stirring was continued for 15 minutes, and then epoxy linseed oil was added and the stirring was continued for 15 minutes;

[0043] S2. Place the mixture obtained in step S1 at 135° C. for 30 minutes to obtain double-regenerated SBS modified asphalt.

[0044] Example 2

[0045] The double regenerated SBS modified asphalt provided in the embodiment of the present application is the same as that in embodiment 1, except that the weight portion of maleic anhydride is 0.1 part;

[0046] The method for preparing double-regenerated SBS modified asphalt provided in the embodiment of the present application has the same process parameters as those in Example 1.

[0047] Example 3

[0048] The double regenerated SBS modified asphalt provided in the embodiment of the present application is the same as that in embodiment 1, except that the weight portion of maleic anhydride is 0.3 parts;

[0049] The method for preparing double-regenerated SBS modified asphalt provided in the embodiment of the present application has the same process parameters as those in Example 1.

[0050] Example 4

[0051] The double regenerated SBS modified asphalt provided in the embodiment of the present application is the same as that in embodiment 1, except that the weight portion of bisphenol A novolac epoxy resin is 3 parts;

[0052] The method for preparing double-regenerated SBS modified asphalt provided in the embodiment of the present application has the same process parameters as those in Example 1.

[0053] Example 5

[0054] The double regenerated SBS modified asphalt provided in the embodiment of the present application is the same as that in embodiment 1, except that the weight portion of bisphenol A novolac epoxy resin is 1 part;

[0055] The method for preparing double-regenerated SBS modified asphalt provided in the embodiment of the present application has the same process parameters as those in Example 1.

[0056] Example 6

[0057] The double regenerated SBS modified asphalt provided in the embodiment of the present application is the same as that in embodiment 1, except that the weight portion of the epoxy linseed oil is 4 parts;

[0058] The method for preparing double-regenerated SBS modified asphalt provided in the embodiment of the present application has the same process parameters as those in Example 1.

[0059] Example 7

[0060] The double regenerated SBS modified asphalt provided in the embodiment of the present application is the same as that in embodiment 1, except that the weight portion of the epoxy linseed oil is 8 parts;

[0061] The method for preparing double-regenerated SBS modified asphalt provided in the embodiment of the present application has the same process parameters as those in Example 1.

[0062] Comparative Example 1

[0063] This comparative example provides a regenerated SBS modified asphalt, comprising the following raw materials in parts by weight: 100 parts of aged SBS modified asphalt, 2 parts of bisphenol A novolac epoxy resin, and 6 parts of epoxy linseed oil;

[0064] Among them, the softening point of the aged SBS modified asphalt is 78.1°C, the ductility at 5°C is 12mm, and the needle penetration at 25°C is 21.3dmm (the preparation method of the aged SBS modified asphalt is the same as that of Example 1);

[0065] Bisphenol A novolac epoxy resin was produced by Shenzhen Huite Chemical Co., Ltd.;

[0066] Epoxidized linseed oil was purchased from Zhejiang Xingbang Polymer Materials Co., Ltd. The specific model is ACS Epoxol Molecular weight is 750-900;

[0067] The preparation steps of the above-mentioned regenerated SBS modified asphalt are as follows:

[0068] S1. According to the above weight parts, the aged SBS modified asphalt was heated at 145°C to a molten state, and then bisphenol A novolac epoxy resin was added at a stirring speed of 1000 rpm, and the stirring was continued for 15 minutes, and then epoxy linseed oil was added and the stirring was continued for 15 minutes;

[0069] S2. Place the mixture in step S1 at 135° C. for 30 minutes to obtain regenerated SBS modified asphalt.

[0070] Comparative Example 2

[0071] This comparative example provides a regenerated SBS modified asphalt, comprising the following raw materials in parts by weight: 100 parts of aged SBS modified asphalt, 2 parts of bisphenol A novolac epoxy resin, and 0.2 parts of maleic anhydride;

[0072] Among them, the softening point of the aged SBS modified asphalt is 78.1°C, the ductility at 5°C is 12mm, and the needle penetration at 25°C is 21.3dmm (the preparation method of the aged SBS modified asphalt is the same as that of Example 1);

[0073] Bisphenol A novolac epoxy resin was produced by Shenzhen Huite Chemical Co., Ltd.;

[0074] Maleic anhydride was produced by Sinopharm Chemical Reagent Co., Ltd.;

[0075] The preparation steps of the above-mentioned regenerated SBS modified asphalt are as follows:

[0076] S1. According to the above weight parts, the aged SBS modified asphalt was heated at 145°C to a molten state, and then bisphenol A novolac epoxy resin and maleic anhydride were added at a stirring speed of 1000 rpm and stirred for 30 minutes;

[0077] S2. Place the mixture in step S1 at 135° C. for 30 minutes to obtain regenerated SBS modified asphalt.

[0078] Comparative Example 3

[0079] This comparative example provides a regenerated SBS modified asphalt, comprising the following raw materials in parts by weight: 100 parts of aged SBS modified asphalt, 6 parts of epoxy linseed oil, and 0.2 parts of maleic anhydride;

[0080] Among them, the softening point of the aged SBS modified asphalt is 78.1°C, the ductility at 5°C is 12mm, and the needle penetration at 25°C is 21.3dmm (the preparation method of the aged SBS modified asphalt is the same as that of Example 1);

[0081] Epoxidized linseed oil was purchased from Zhejiang Xingbang Polymer Materials Co., Ltd. The specific model is ACS Epoxol Molecular weight is 750-900;

[0082] Maleic anhydride was produced by Sinopharm Chemical Reagent Co., Ltd.;

[0083] The preparation steps of the above-mentioned regenerated SBS modified asphalt are as follows:

[0084] S1. According to the above weight parts, the aged SBS modified asphalt was heated at 145°C to a molten state, and then maleic anhydride was added at a stirring speed of 1000 rpm and stirred for 15 minutes, and then epoxy linseed oil was added and stirred for 15 minutes;

[0085] S2. Place the mixture in step S1 at 135° C. for 30 minutes to obtain regenerated SBS modified asphalt.

[0086] Comparative Example 4

[0087] The comparative example of the present application provides a regenerated SBS modified asphalt, comprising the following raw materials in parts by weight: 100 parts of aged SBS modified asphalt, 2 parts of bisphenol A novolac epoxy resin, 6 parts of epoxy soybean oil, and 0.2 parts of maleic anhydride;

[0088] Among them, the softening point of the aged SBS modified asphalt is 78.1°C, the ductility at 5°C is 12mm, and the needle penetration at 25°C is 21.3dmm (the preparation method of the aged SBS modified asphalt is the same as that of Example 1);

[0089] Epoxidized soybean oil is produced by Guangzhou Fufei Chemical Technology Co., Ltd. It is a light yellow viscous oily liquid at room temperature with a molecular weight of 950-1050;

[0090] Bisphenol A novolac epoxy resin was produced by Shenzhen Huite Chemical Co., Ltd.;

[0091] Maleic anhydride was produced by Sinopharm Chemical Reagent Co., Ltd.;

[0092] The preparation steps of the above-mentioned regenerated SBS modified asphalt are as follows:

[0093] S1. According to the above weight portions, the aged SBS modified asphalt was heated at 145°C to a molten state, and then bisphenol A novolac epoxy resin and maleic anhydride catalyst were added respectively at a stirring speed of 1000 rpm, and the stirring was continued for 15 minutes, and then the epoxy soybean oil was added and the stirring was continued for 15 minutes.

[0094] S2. Place the mixture in S1 at 135°C for 30 minutes to obtain regenerated SBS modified asphalt.

[0095] Comparative Example 5

[0096] The comparative example of the present application provides a regenerated SBS modified asphalt, comprising the following raw materials in parts by weight: 100 parts of aged SBS modified asphalt, 2 parts of epoxidized polybutadiene resin, 6 parts of epoxidized linseed oil, and 0.2 parts of maleic anhydride catalyst;

[0097] Among them, the softening point of the aged SBS modified asphalt is 78.1°C, the ductility at 5°C is 12mm, and the needle penetration at 25°C is 21.3dmm (the preparation method of the aged SBS modified asphalt is the same as that of Example 1);

[0098] The epoxidized polybutadiene resin is produced by Japan Soda Co., Ltd., with a number average molecular weight of 2100-2300, a kinematic viscosity of 900-1100 mPa·s at 45°C, and an epoxy equivalent of 110-120 g / mol;

[0099] Epoxidized linseed oil was purchased from Zhejiang Xingbang Polymer Materials Co., Ltd. The specific model is ACS Epoxol Molecular weight is 750-900;

[0100] Maleic anhydride was produced by Sinopharm Chemical Reagent Co., Ltd.;

[0101] The preparation steps of the above-mentioned regenerated SBS modified asphalt are as follows:

[0102] S1. According to the above weight portions, the aged SBS modified asphalt was heated at 145°C to a molten state, and then the epoxidized polybutadiene resin and the maleic anhydride catalyst were added respectively at a stirring speed of 1000 rpm, and the stirring was continued for 15 minutes. Then, the epoxidized linseed oil was added and the stirring was continued for 15 minutes.

[0103] S2. Place the mixture in S1 at 135°C for 30 minutes to obtain regenerated SBS modified asphalt.

[0104] Performance Testing

[0105] The softening point, needle penetration and ductility at 5°C of the double regenerated (or regenerated) SBS modified asphalt prepared in the above Examples 1 to 7 and Comparative Examples 1 to 5, as well as the aged SBS modified asphalt and the unaged SBS modified asphalt (i.e., the SBS modified asphalt mentioned above) used were tested respectively. The results are shown in Table 1 below.

[0106] Table 1 - Properties of modified asphalt prepared in different embodiments

[0107]

[0108]

[0109] It can be seen from the performance test results in Table 1 that through the double regeneration process of Example 1, the ductility of the aged SBS modified asphalt is increased by 242mm, the softening point is decreased by 14.6℃, and the penetration is decreased by 20.5dmm. Compared with the performance of the unaged SBS modified asphalt, it is found that the double regeneration technology can restore 94.8% of the low-temperature performance of the aged SBS modified asphalt. Through the regeneration process of Comparative Example 1, the ductility of the aged SBS modified asphalt is increased by 200mm, the softening point is decreased by 20.6℃, and the penetration is increased by 25.8dmm. In addition, compared with the regenerated SBS modified asphalt in Comparative Example 1, the ductility and softening point of Example 1 are 42mm and 6.0℃ higher, respectively, and the penetration is 5.3dmm lower, which shows that the catalytic effect of maleic anhydride achieves the repair effect of bisphenol A novolac epoxy resin on the SBS molecular structure.

[0110] The performance test results of Examples 1 to 3 show that the softening point of the double-regenerated SBS modified asphalt increases with the increase of maleic anhydride dosage, while the change trend of the needle penetration is the opposite. It is worth noting that the ductility of the double-regenerated SBS modified asphalt does not increase when the maleic anhydride dosage increases to 0.3 parts, but decreases significantly. Therefore, it can be concluded that the optimal dosage of maleic anhydride is 0.2 parts. At this dosage, the ductility and softening point of the double-regenerated SBS modified asphalt can meet the technical requirements of ID-type SBS modified asphalt.

[0111] By comparing and analyzing Examples 1, 4 to 5, it can be concluded that the ductility and softening point of the double-regenerated SBS modified asphalt increase with the increase in the amount of bisphenol A novolac epoxy resin. Compared with Comparative Example 3 in which no bisphenol A novolac epoxy resin is added, the ductility and softening point of the double-regenerated SBS modified asphalt of these three groups of examples are significantly greater, which once again shows that bisphenol A novolac epoxy resin can repair the SBS molecular structure under the action of a catalyst. At the same time, when the amount of bisphenol A novolac epoxy resin reaches 2 parts, the performance improvement is very small, which shows that this amount can already meet the repair needs of all aged SBS molecules.

[0112] By comparing and analyzing Examples 1, 6 to 7, it can be seen that the ductility and penetration of the double-regenerated SBS modified asphalt increase with the increase in the amount of epoxy linseed oil, while the softening point shows the opposite trend. Compared with Comparative Example 2 in which no epoxy linseed oil is added, the ductility of the double-regenerated SBS modified asphalt in the above three groups of examples is significantly greater. The above results show that epoxy linseed oil, as a light oil, can, on the one hand, adjust the components of aged asphalt and improve low-temperature crack resistance; on the other hand, it enhances the permeability of bisphenol A novolac epoxy resin in aged SBS modified asphalt, connects macromolecules such as asphaltene, and thereby enhances the repair effect of the regeneration agent on the SBS molecular structure.

[0113] By comparing and analyzing Example 1 and Comparative Example 4, it can be seen that, under the same dosage, epoxy linseed oil can make the aged SBS modified asphalt have higher low-temperature ductility than epoxy soybean oil, and the softening effect is more obvious, which is manifested in a greater decrease in the softening point of the aged SBS modified asphalt. This can be attributed to the smaller molecular weight of epoxy linseed oil than that of epoxy soybean oil, which has better compatibility with the aged asphalt and can further enhance the penetration of bisphenol A novolac epoxy resin in the aged SBS modified asphalt.

[0114] By comparing and analyzing Example 1 and Comparative Example 5, it can be seen that, under the same dosage, the effect of bisphenol A novolac epoxy resin on improving the low-temperature ductility and softening point of aged SBS modified asphalt is more obvious than that of epoxidized polybutadiene resin. This is because compared with epoxidized polybutadiene resin, bisphenol A novolac epoxy resin has a larger epoxy value and average molecular weight, so it is easier to chemically react with aged SBS and form a longer SBS molecular chain.

[0115] 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 principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing double-regenerated SBS modified asphalt, characterized in that: The double regenerated SBS modified asphalt comprises the following raw materials in parts by weight: 100 parts of aged SBS modified asphalt, 3 parts of bisphenol A novolac epoxy resin, 6 parts of epoxy linseed oil, and 0.2 parts of maleic anhydride; Among them, the softening point of aged SBS modified asphalt is 78.1℃, the ductility at 5℃ is 12mm, and the needle penetration at 25℃ is 21.3dmm, where 1dmm=0.1mm; The molecular weight of the epoxy linseed oil is 750-900; The preparation method of the double-regenerated SBS modified asphalt comprises the following steps: S1. According to the above weight portions, the aged SBS modified asphalt was heated at 145°C to a molten state, and then bisphenol A novolac epoxy resin and maleic anhydride catalyst were added respectively at a stirring speed of 1000 rpm, and the stirring was continued for 15 minutes, and then epoxy linseed oil was added and the stirring was continued for 15 minutes; S2. Place the mixture obtained in step S1 at 135° C. for 30 minutes to obtain double-regenerated SBS modified asphalt.

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