CN110819129B - Functional assembled magnesium-aluminum-based layered double-hydroxide modifier and preparation method and application thereof - Google Patents

Abstract

The invention discloses a functional assembled magnalium-based layered double-hydroxide modifier and a preparation method thereof, wherein the modifier is prepared by co-functionally assembling LDHs intercalation modification and surface modifier organic modification by an anionic antioxidant active component; by grafting the surface modifier of the long-chain branch organic functional group to the surface of the LDHs, the polar group on the surface of the LDHs is reduced by means of the chemical action between the surface modifier and the LDHs, the agglomeration among LDHs particles is inhibited, the dispersibility of the LDHs in the asphalt is improved, meanwhile, the lipophilicity of the LDHs can be enhanced by the introduced long-chain branch organic functional group, the compatibility stability with the asphalt is enhanced, and the thermal oxidation resistance and ultraviolet aging resistance of the asphalt are obviously improved.

Description

A kind of functionalized assembled magnesium-aluminum base layer-shaped double hydroxy metal hydroxide modifier and preparation method and application thereof

technical field

The invention belongs to the technical field of asphalt modification, and in particular relates to a functionalized assembled magnesium-aluminum base layer-shaped double hydroxy metal hydroxide (LDHs) modifier and a preparation method and application thereof.

Background technique

Asphalt pavement has the advantages of comfortable driving, low noise, easy maintenance and high safety, making it widely used in highway construction. Asphalt materials are prone to aging under the influence of external environmental factors (such as heat, ultraviolet light, oxygen, etc.), and the aging of asphalt materials leads to rutting, potholes and cracks on asphalt pavements, which seriously affects the service life of asphalt pavements. Asphalt aging is mainly divided into thermal oxygen and ultraviolet aging, both of which can lead to the cracking of asphalt material properties, and these two kinds of aging show obvious coupling effect. The anti-aging technology of bituminous materials only aimed at one aspect cannot effectively improve its anti-aging ability.

In order to improve the anti-aging performance of asphalt, patent CN102181161B discloses an anti-aging modified asphalt of magnesium-aluminum-based double hydroxides (LDHs). Adding it to asphalt can improve the anti-ultraviolet aging ability of asphalt. However, because the surface of LDHs laminates contains a large number of polar groups, it is prone to agglomeration, which leads to the inability to uniformly disperse in the asphalt, thus limiting the ability of LDHs to fully exert its anti-ultraviolet aging ability. On the other hand, although LDHs have good anti-ultraviolet aging ability, their performance in anti-thermal oxidative aging is mediocre. Patent CN103526891B discloses a method for simultaneously enhancing the anti-ultraviolet aging and anti-thermal-oxidative aging capabilities of materials by compounding LDHs and antioxidants. However, if LDHs and antioxidants are simply compounded, the Oxygen agents will continue to migrate from the asphalt matrix to the surface, resulting in a significant weakening of its thermal-oxidative aging resistance and long-term effectiveness.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is that in view of the above-mentioned deficiencies in the prior art, the present invention provides a functionalized assembled magnesium-aluminum base layer-shaped double hydroxy metal hydroxide (LDHs) modifier for modifying asphalt to obtain Asphalt material with excellent UV aging resistance, thermal oxidation resistance and comprehensive performance.

In order to achieve the above object, technical scheme of the present invention is as follows:

A functionalized assembled magnesium-aluminum base layer-shaped double hydroxy metal hydroxide (LDHs) modifier, which is composed of LDHs, anionic antioxidant active ingredients, and surface modifiers. The weight parts of each raw material are: 60 parts. ~85 parts LDHs, 12 parts~35 parts anionic antioxidant active ingredients, 3 parts~15 parts surface modifier. The functionally assembled LDHs are prepared by the intercalation modification of LDHs by an anionic antioxidant active ingredient and the organic modification and modification of the surface of LDHs by a surface modifier.

The LDHs are obtained according to the preparation method disclosed in CN102181161B.

The active ingredient of the anionic antioxidant is any one of diphenylamine sulfide and diisooctyl diphenylamine.

The surface modifier is any one of methacryloyloxyundecylmethyldiethoxysilane, hexadecyltrimethoxysilane and octadecyltrimethoxysilane.

The preparation method of the above-mentioned functionalized assembly LDHs modifier, comprises the following steps:

1) The LDHs were first placed in a muffle furnace at 550 °C for 120 min to remove the interlayer anions of LDHs, and then the treated LDHs were mixed with anionic antioxidant active ingredient solution (anionic antioxidant active ingredient and The water volume ratio is 8:2) uniformly stirred for 60 min under low speed conditions, and finally the intercalated modified LDHs were vacuum filtered, repeatedly washed, dried and pulverized to obtain the anionic antioxidant active ingredient intercalated modified LDHs. Sexual LDHs;

2) Add the prepared intercalation modified LDHs to an ethanol-water solution with a volume ratio of 95:5, stir at 50 °C for 30 min, and slowly add acetic acid dropwise to control the pH of the mixed solution at 3-4;

3) Add the surface modifier to the mixed solution obtained in step 2), firstly at 50°C and with a pH of 3 to 4 for a rapid stirring reaction for 150 min, then increase the temperature to 70°C and continue the reaction for 30 min; Finally, the modified LDHs were vacuum filtered, washed, dried, and ground into powder with a particle size of less than 0.075 mm, and the functionalized assembled LDHs modifier was obtained.

The invention also discloses a functionalized assembled LDHs modified asphalt, which is composed of asphalt and functionalized assembled LDHs. .

The asphalt is road petroleum asphalt, the penetration at 25°C is 60 dmm~100 dmm, the softening point is 40°C~55°C, and the ductility at 10°C is 15 cm~25 cm.

The preparation method of the above-mentioned functionalized assembly LDHs modified asphalt comprises the following steps:

The prepared functionalized assembled LDHs modifier was added to asphalt, and melt-blended at 150 °C and a shear rate of 5000 rpm for 90 min. Modified Asphalt.

The beneficial effects of the present invention are as follows:

1) LDHs have excellent anti-ultraviolet aging ability, but the anti-oxidative aging ability of LDHs is general. The present invention utilizes the adjustable spacing of the LDHs layers to intercalate the active components of anionic antioxidants into the LDHs layers to enhance the LDHs resistance to thermal oxidation. At the same time, by intercalating the antioxidant into the LDHs layer, it can also prevent the antioxidant from migrating to the surface in the asphalt by the spatial confinement of the LDHs layer, so as to enhance the long-term effect of the antioxidant.

2) In the present invention, the surface modifier is grafted to the LDHs surface after intercalation modification, and the surface modifier is used to react with the polar groups on the surface of LDHs to inhibit the agglomeration between LDHs particles and significantly improve the LDHs in asphalt. The dispersibility of LDHs and the introduction of organic functional groups on the surface of LDHs by surface modifiers can significantly improve the compatibility and stability of LDHs in asphalt.

3) The present invention modifies the asphalt with the above-mentioned functionalized assembled LDHs, which can simultaneously enhance the thermal oxygen resistance and ultraviolet aging resistance of the asphalt, and the obtained modified asphalt has excellent comprehensive performance.

Detailed ways

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

The preparation method of the functionalized assembled magnesium-aluminum-based layered double hydroxy metal hydroxide (LDHs) modifier adopted in the following examples is as follows: 1) first place the LDHs in a muffle furnace at 550 ° C for 120 min, To remove LDHs interlayer anions, then the treated LDHs and anionic antioxidant active ingredient solution (the volume ratio of anionic antioxidant active ingredient to water is 8:2) were uniformly stirred at low speed for 60 min. Intercalation-modified LDHs are subjected to vacuum filtration, repeated washing, drying, and pulverization to obtain LDHs of intercalation-modified anionic antioxidant active components;

2) Add the prepared intercalation-modified LDHs to an ethanol-water solution with a volume ratio of 95:5, stir at 50 °C for 30 min, and slowly add acetic acid dropwise to control the pH of the mixed solution at 3-4;

3) Add the surface modifier to the mixed solution obtained in step 2, firstly at 50 °C and PH of 3 to 4 for a rapid stirring reaction for 150 min, then increase the temperature to 70 °C and continue the reaction for 30 min; finally The modified LDHs are vacuum filtered, washed, dried, and ground into powder with a particle size of less than 0.075 mm, and then the functionalized assembled LDHs modifier can be obtained.

Example 1:

The functionalized assembled LDHs required in Example 1 can be prepared according to the method steps of the functionalized assembled LDHs modifier, wherein the active ingredient of the anionic antioxidant is diphenylamine sulfide, and the surface modifier is methacryloyl Oxyundecylmethyldiethoxysilane, the mass parts of each raw material are as follows: 85 parts of LDHs, 12 parts of diphenylamine sulfide, 3 parts of methacryloxyundecylmethyldiethoxysilane .

After selecting 95 parts (penetration at 25°C of 65 dmm, softening point of 45°C, and ductility of 22 cm at 10°C), road petroleum asphalt was heated to a flowing state, and then the high-speed shearing machine was started, and the shear rate was continued at 150°C. At 5000 rpm, 5 parts of the prepared functionalized assembled LDHs modifier were slowly added for melt blending for 90 min, and then the modified asphalt with excellent thermal-oxidative aging resistance, UV aging resistance and comprehensive properties could be obtained.

Comparative Example 1:

According to the preparation method of functionalized assembled LDHs modifier (diphenylamine sulfide is not added in step 1, and methacryloyloxyundecylmethyldiethoxysilane is not added in step 3), LDHs are treated in the same way, that is, The comparative sample a of the functionalized assembled LDHs in Example 1 was obtained.

The operation was carried out according to the preparation method of modified asphalt in Example 1 (during the process of adding functionalized assembled LDHs to the comparative sample, diphenylamine sulfide and methacryloyloxyundecylmethyldiethoxysilane were added simultaneously, The mixing amount of the raw material is the same as that of Example 1), and the comparative sample b of the modified asphalt of Example 1 can be obtained.

The asphalt samples prepared in Example 1 and Comparative Example 1 were respectively subjected to high-temperature storage stability tests, short-term thermal oxidative aging (RTFOT) and ultraviolet aging (UV), and some physical performance indicators before and after aging were tested. The obtained The results are shown in Table 1 and Table 2.

According to the test results of high temperature storage stability in Table 1, it is found that the dispersibility and compatibility stability of LDHs modified by functionalized assembly in asphalt are significantly improved; the test results in Table 2 show that the modified asphalt with functionalized assembled LDHs has better resistance to Thermal oxidative aging and anti-ultraviolet aging ability.

Example 2:

The functionalized assembled LDHs required in Example 2 can be prepared according to the method steps of the functionalized assembled LDHs modifier, wherein the active ingredient of the anionic antioxidant is diphenylamine sulfide, and the surface modifier is hexadecyl For trimethoxysilane, the mass parts of each raw material are as follows: 60 parts of LDHs, 35 parts of diphenylamine sulfide, and 5 parts of hexadecyltrimethoxysilane.

Select 91 parts (penetration at 25 °C of 65 dmm, softening point of 45 °C, and ductility of 22 cm at 10 °C) after heating the road petroleum asphalt to a flowing state, start the high-speed shearing machine, and continue at 150 °C, the shear rate At 5000 rpm, 9 parts of the prepared functionalized assembled LDHs modifier were slowly added for melt blending for 90 min, and then the modified asphalt with excellent thermal-oxidative aging resistance, UV aging resistance and comprehensive properties could be obtained.

Comparative Example 2:

According to the preparation method of functionalized assembled LDHs modifier (diphenylamine sulfide is not added in step 1, and hexadecyltrimethoxysilane is not added in step 3), LDHs are treated in the same way, and the functionalized assembled LDHs of Example 2 is obtained. Comparative sample c.

The operation was carried out according to the preparation method of modified asphalt in Example 2 (during the process of adding functionalized assembled LDHs to the comparative sample, diphenylamine sulfide and hexadecyltrimethoxysilane were added at the same time, and the content of the raw materials was the same as that in Example 2. ), the comparative sample d of the modified asphalt in Example 2 can be obtained.

The asphalt samples prepared in Example 2 and Comparative Test 2 were respectively subjected to high temperature storage stability test, short-term thermal oxidative aging (RTFOT) and ultraviolet aging (UV), and some physical performance indicators before and after aging were tested. The obtained The results are shown in Table 3 and Table 4.

According to the high temperature storage stability test results in Table 3, it is found that the dispersibility and compatibility stability of LDHs modified by functionalized assembly in asphalt are significantly improved; the test results in Table 4 show that the functionalized assembled LDHs modified asphalt has better resistance to Thermal oxidative aging and anti-ultraviolet aging ability.

Example 3:

The functionalized assembled LDHs required in Example 3 can be prepared according to the method steps of the functionalized assembled LDHs modifier, wherein the active ingredient of the anionic antioxidant is diphenylamine sulfide, and the surface modifier is octadecyl For trimethoxysilane, the mass parts of each raw material are as follows: 70 parts of LDHs, 15 parts of diphenylamine sulfide, and 15 parts of octadecyltrimethoxysilane.

Select 85 parts (penetration of 65 dmm at 25 °C, softening point of 45 °C, and ductility of 22 cm at 10 °C). At 5000 rpm, 15 parts of the prepared functionalized assembled LDHs modifier were slowly added for melt blending for 90 min, and then the modified asphalt with excellent thermal oxidation resistance, UV resistance and comprehensive properties could be obtained.

Comparative Example 3:

According to the preparation method of functionalized assembled LDHs modifier (diphenylamine sulfide was not added in step 1, and octadecyltrimethoxysilane was not added in step 3), LDHs were treated in the same way, and the functionalized assembled LDHs of Example 3 was obtained. Contrast sample e.

The operation was carried out according to the preparation method of modified asphalt in Example 3 (during the process of adding functionalized assembled LDHs to the comparative sample, diphenylamine sulfide and octadecyltrimethoxysilane were added at the same time, and the amount of raw materials was the same as that in Example 3. ), the comparative sample f of the modified asphalt in Example 3 can be obtained.

The asphalt samples prepared in Example 3 and Comparative Example 3 were respectively subjected to high temperature storage stability test, short-term thermal oxidative aging (RTFOT) and ultraviolet aging (UV), and some physical performance indicators before and after aging were tested. The obtained The results are shown in Table 5 and Table 6.

According to the high temperature storage stability test results in Table 5, it is found that the dispersibility and compatibility stability of LDHs modified by functionalized assembly in asphalt are significantly improved; the test results in Table 6 show that the functionalized assembled LDHs modified asphalt has better resistance to Thermal oxidative aging and anti-ultraviolet aging ability.

Example 4:

The functionalized assembled LDHs required in Example 4 can be prepared according to the method steps of the functionalized assembled LDHs modifier, wherein the active ingredient of the anionic antioxidant is diisooctyldiphenylamine, and the surface modifier is methyl methacrylate methacryloyloxyundecylmethyldiethoxysilane, the parts by mass of each raw material are as follows: 65 parts of LDHs, 20 parts of diisooctyldiphenylamine, 15 parts of methacryloyloxyundecylmethyl Diethoxysilane.

Select 99 parts (penetration at 25 °C of 65 dmm, softening point of 45 °C, and ductility of 22 cm at 10 °C) after heating the road petroleum asphalt to a flowing state, start the high-speed shearing machine, and continue at 150 °C with the shear rate One part of the prepared functionalized assembled LDHs modifier was slowly added for 90 min under the condition of 5000 rpm for melt blending, and then the modified asphalt with excellent thermal-oxidative aging resistance, UV aging resistance and comprehensive properties could be obtained.

Comparative Example 4:

According to the preparation method of functionalized assembled LDHs modifier (no diisooctyl diphenylamine was added in step 1, and no methacryloyloxyundecylmethyldiethoxysilane was added in step 3), the same procedure was performed for LDHs. After processing, a comparative sample j of the functionalized assembled LDHs in Example 4 was obtained.

The operation was carried out according to the preparation method of modified asphalt in Example 4 (during the process of adding functionalized assembled LDHs to the comparative sample, diisooctyl diphenylamine and methacryloyloxyundecylmethyldiethoxy were added at the same time. base silane, the content of the raw materials is the same as that in Example 4), the comparative sample h of the modified asphalt in Example 4 can be obtained.

The asphalt samples prepared in Example 4 and Comparative Example 4 were respectively subjected to high temperature storage stability test, short-term thermal oxidative aging (RTFOT) and ultraviolet aging (UV), and some physical performance indicators before and after aging were tested. The obtained The results are shown in Table 7 and Table 8.

According to the high temperature storage stability test results in Table 7, it is found that the dispersibility and compatibility stability of LDHs modified by functionalized assembly in asphalt are significantly improved; the test results in Table 8 show that the functionalized assembled LDHs modified asphalt has better resistance to Thermal oxidative aging and anti-ultraviolet aging ability.

Example 5:

The functionalized assembled LDHs required in Example 5 can be prepared according to the method steps of the functionalized assembled LDHs modifier, wherein the active ingredient of the anionic antioxidant is diisooctyldiphenylamine, and the surface modifier is ten For hexaalkyltrimethoxysilane, the mass parts of each raw material are as follows: 80 parts of LDHs, 12 parts of diisooctyldiphenylamine, and 8 parts of hexadecyltrimethoxysilane.

Select 88 parts (penetration of 65 dmm at 25 °C, softening point of 45 °C, and ductility of 22 cm at 10 °C) after heating the road petroleum asphalt to a flowing state, start the high-speed shearing machine, and continue at 150 °C with the shear rate of At 5000 rpm, 12 parts of the prepared functionalized assembled LDHs modifier were slowly added for melt blending for 90 min, and then the modified asphalt with excellent thermal-oxidative aging resistance, UV aging resistance and comprehensive properties could be obtained.

Comparative Example 5:

According to the preparation method of functionalized assembled LDHs modifier (no diisooctyl diphenylamine was added in step 1, and no hexadecyltrimethoxysilane was added in step 3), LDHs were treated in the same way to obtain the functionalized product of Example 5. Comparative sample k of assembled LDHs.

The operation was carried out according to the preparation method of modified asphalt in Example 5 (during the process of adding functionalized assembled LDHs to the comparative sample, diisooctyl diphenylamine and cetyltrimethoxysilane were added at the same time. Example 5 is the same), the comparative sample 1 of the modified asphalt of Example 5 can be obtained.

The asphalt samples prepared in Example 5 and Comparative Example 5 were respectively subjected to high-temperature storage stability tests, short-term thermal oxidative aging (RTFOT) and ultraviolet aging (UV), and some physical performance indicators before and after aging were tested. The results are shown in Table 9 and Table 10.

According to the high temperature storage stability test results in Table 9, it is found that the dispersibility and compatibility stability of LDHs modified by functionalized assembly in asphalt are significantly improved; the test results in Table 10 show that the functionalized assembled LDHs modified asphalt has better resistance to Thermal oxidative aging and anti-ultraviolet aging ability.

Example 6:

The functionalized assembled LDHs required in Example 6 can be prepared according to the method steps of the functionalized assembled LDHs modifier, wherein the active ingredient of the anionic antioxidant is diisooctyldiphenylamine, and the surface modifier is ten For octaalkyltrimethoxysilane, the mass parts of each raw material are as follows: 75 parts of LDHs, 22 parts of diisooctyldiphenylamine, and 3 parts of octadecyltrimethoxysilane.

After selecting 97 parts (penetration at 25°C of 65 dmm, softening point of 45°C, and ductility of 22 cm at 10°C), road petroleum asphalt was heated to a flowing state, and then the high-speed shearing machine was started, and the shear rate was continued at 150°C. At 5000 rpm, 3 parts of the prepared functionalized assembled LDHs modifier were slowly added for melt blending for 90 min, and then the modified asphalt with excellent thermal-oxidative aging resistance, UV aging resistance and comprehensive properties could be obtained.

Comparative Example 6:

According to the preparation method of functionalized assembled LDHs modifier (no diisooctyl diphenylamine was added in step 1, and no octadecyltrimethoxysilane was added in step 3), LDHs were treated in the same way to obtain the functionalization of Example 6. Comparative samples m of assembled LDHs.

The operation was carried out according to the preparation method of modified asphalt in Example 6 (during the process of adding functionalized assembled LDHs to the comparative sample, diisooctyl diphenylamine and octadecyltrimethoxysilane were added at the same time. Example 6 is the same), the comparative sample n of the modified asphalt of Example 6 can be obtained.

The asphalt samples prepared in Example 6 and Comparative Example 6 were respectively subjected to high-temperature storage stability tests, short-term thermal oxidative aging (RTFOT) and ultraviolet aging (UV), and some physical performance indicators before and after aging were tested. The obtained The results are shown in Table 11 and Table 12.

According to the test results of high temperature storage stability in Table 11, it is found that the dispersibility and compatibility stability of LDHs modified by functionalized assembly are significantly improved in asphalt; the test results in Table 12 show that the functionalized assembled LDHs modified asphalt has better resistance to Thermal oxidative aging and anti-ultraviolet aging ability.

Each raw material listed in the present invention, as well as the upper and lower limits and interval values of each raw material in the present invention, can realize the present invention, and the embodiments are not listed one by one here.

Claims (4)

1. A functional assembled magnesium aluminum base layered double hydroxide modifier is characterized in that: the modifier comprises the following raw materials in parts by weight: 60-85 parts of LDHs, 12-35 parts of anionic antioxidant active ingredients and 3-15 parts of surface modifier; the anionic antioxidant active ingredient is vulcanized diphenylamine or diisooctyl diphenylamine; the surface modifier is any one of methacryloxy undecyl methyldiethoxysilane, hexadecyl trimethoxy silane and octadecyl trimethoxy silane;

the preparation method of the functional assembled magnesium aluminum base layered double hydroxide modifier comprises the following steps:

1) firstly, putting LDHs in a muffle furnace at 550 ℃ for 120 min, removing interlayer anions of the LDHs, then uniformly stirring the treated LDHs and an anionic antioxidant active component solution at low speed for 60 min, and then carrying out vacuum filtration, repeated washing, drying and crushing on the LDHs subjected to intercalation modification to obtain anionic antioxidant active component intercalation modified LDHs;

2) adding the anionic antioxidant active ingredient intercalation modified LDHs prepared in the step 1) into an ethanol-water solution with a volume ratio of 95:5, stirring for 30 min at 50 ℃, and slowly dropwise adding acetic acid to control the pH of the mixed solution to be 3-4;

3) adding a surface modifier into the mixed solution obtained in the step 2), quickly stirring and reacting for 150 min under the conditions of 50 ℃ and pH of 3-4, then raising the temperature to 70 ℃, and continuing to react for 30 min; and then carrying out vacuum filtration, washing, drying and grinding to obtain powder with the particle size of less than 0.075 mm, thus obtaining the functional assembled magnalium-based layered double hydroxide modifier.

2. The use of the functionalized assembled magnesium aluminum based layered double hydroxide modifier of claim 1 in modified asphalt, wherein the modified asphalt comprises the functionalized assembled magnesium aluminum based layered double hydroxide modifier and asphalt in parts by weight: 85-99 parts of asphalt and 1-15 parts of functionally assembled magnesium-aluminum-based layered double hydroxide modifier.

3. The use of the functionalized assembled magnesium aluminum-based layered double hydroxide modifier in modified asphalt as claimed in claim 2, wherein the asphalt is road petroleum asphalt with a penetration of 60 dmm to 100 dmm at 25 ℃, a softening point of 40 to 55 ℃ and a ductility of 15 cm to 25 cm at 10 ℃.

4. The use of the functionalized assembled magnesium aluminum based layered double hydroxide modifier as claimed in claim 2 in modified asphalt, wherein the modified asphalt is prepared by a method comprising the steps of: adding the functional assembled magnalium base layered double hydroxide modifier into asphalt according to the proportion, and then carrying out melt blending for 90 min under the conditions of 150 ℃, and the shear rate of 5000 rpm, thus obtaining the modified asphalt.