Odorless environment-friendly microcapsule, odorless environment-friendly asphalt additive and preparation method thereof

Abstract

The application discloses a kind of odorless environmental protection microcapsules, odorless environmental protection asphalt additive and its preparation method.The odorless environmental protection microcapsules of the application include composite shell material and core material, wherein the composite shell material includes inorganic base layer shell / nano tomaline / polydopamine, and the core material includes one or more odorless agents;The surface of the shell material is loaded with metal chelate.The odorless environmental protection microcapsules of the application can not only efficiently and durably reduce the content of irritating gas in asphalt fume, but also make asphalt emit pleasant fragrance during construction, providing a new idea for the environmental protection application of asphalt.

Description

Technical Field

[0001] This invention belongs to the field of environmentally friendly asphalt, specifically relating to a odor-neutralizing and environmentally friendly microcapsule, an odor-neutralizing and environmentally friendly asphalt additive, and their preparation method. Background Technology

[0002] Traditional asphalt pavements, while meeting the traffic requirements of vehicles and pedestrians due to their excellent performance, also generate large amounts of toxic and harmful asphalt fumes with pungent odors during the mixing and paving process. This leads to a series of environmentally unfriendly problems, hinders economic development, and threatens human health. Therefore, it is essential to conduct research on reducing harmful gas emissions during the construction of asphalt pavements.

[0003] The commonly used method for reducing asphalt fumes is the additive modification method. The additives used in this method are usually highly active aroma compounds. After being added to asphalt, they can not only enhance the aroma and suppress the odor, but also react with the volatile and more active components in asphalt to improve their molecular weight and stability, and prevent them from decomposing and volatilizing at high temperatures, thereby reducing the amount of irritating fumes released from asphalt during construction.

[0004] To better mix and react with asphalt, additives need to be added when the asphalt temperature is high. However, the additives used in the additive modification method usually have low boiling points, which means that some additives will volatilize before they can react chemically with the relevant components in the asphalt, reducing their smoke emission reduction and odor suppression effects. In addition, related studies have shown that the compounds formed by the reaction of additives with asphalt-related components have poor storage stability and are prone to decomposition after being stored at high temperatures for a period of time. This means that the smoke emission reduction effect of the prepared asphalt will decrease with the increase of storage time.

[0005] CN111849027A discloses an environmentally friendly, odor-neutralizing asphalt modifier and the modified asphalt thereof. This modified asphalt is prepared by directly adding low-boiling-point smoke-suppressing compounds to asphalt and stirring. However, the odor-neutralizing effect of the asphalt prepared using this method is short-lived, requiring immediate application after preparation and making it unsuitable for long-term transportation or storage.

[0006] In summary, the preparation of odor-free and environmentally friendly asphalt using additive modification methods usually suffers from the problem of not being able to be stored for a long time, making it difficult to apply on a large scale. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides an odor-neutralizing and environmentally friendly microcapsule, an odor-neutralizing and environmentally friendly asphalt additive, and their preparation method. The odor-neutralizing and environmentally friendly microcapsule of this invention can not only efficiently and persistently reduce the content of irritating gases in asphalt fumes, but also allow the asphalt to emit a pleasant aroma during construction, providing a completely new approach to the environmentally friendly application of asphalt.

[0008] The first aspect of the present invention provides a deodorizing and environmentally friendly microcapsule, the deodorizing and environmentally friendly microcapsule comprising a composite shell material and a core material, wherein the composite shell material comprises an inorganic base shell / nano-tourmaline / polydopamine, and the core material comprises one or more deodorizing agents; the surface of the shell material is loaded with a metal chelate.

[0009] Furthermore, the particle size of the odor-neutralizing and environmentally friendly microcapsules is 1-5 μm.

[0010] Furthermore, the mass ratio of the odor-neutralizing and environmentally friendly microcapsule composite shell material to the core material is 1:(0.5-2).

[0011] Furthermore, the deodorizing agent is one or more of aldehydes, alcohols, esters, and ketones, preferably including aldehydes, alcohols, esters, and ketones simultaneously.

[0012] Further, the aldehydes are selected from one or more of aliphatic aldehydes with more than 10 carbon atoms and aromatic aldehydes with more than 7 carbon atoms. The aliphatic aldehydes with more than 10 carbon atoms are selected from one or more of 2-methylundecaldehyde and 10-undecenaldehyde; the aromatic aldehydes with more than 7 carbon atoms are selected from one or more of benzaldehyde, cinnamaldehyde, o-methoxy-p-methylbenzaldehyde, 2-methyl-3-(4-isopropylphenyl)propanal, and 2-methyl-3-(3,4-methylenedioxyphenyl)propanal.

[0013] Further, the alcohols are selected from one or more of terpenols with more than 10 carbon atoms and cyclic terpenols with more than 10 carbon atoms. The terpenols with more than 10 carbon atoms are selected from one or more of geraniol, linalool, citronellol, ionol, fenestrate alcohol, myrcene alcohol, lavender alcohol, and nerolidol; the cyclic terpenols with more than 10 carbon atoms are selected from one or more of menthol, terpineol, isobornol, cedrol, and santalol.

[0014] Further, the esters are selected from one or more of aromatic esters with more than 12 carbon atoms and terpene esters with more than 11 carbon atoms. The aromatic esters with more than 12 carbon atoms are selected from one or more of isoamyl benzoate, benzyl benzoate, isoamyl salicylate, benzyl salicylate, leaf salicylate, benzyl cinnamate, and phenethyl cinnamate; the terpene esters with more than 11 carbon atoms are selected from one or more of geraniol formate, geraniol acetate, geraniol propionate, nerol acetate, linalool formate, linalool propionate, lavender acetate, and citronellol butyrate.

[0015] Furthermore, the ketones are selected from one or more of aliphatic ketones with more than 3 carbon atoms and cyclic terpenoid ketones with more than 10 carbon atoms. The aliphatic ketones with more than 3 carbon atoms are selected from one or more of 3-hydroxy-2-butanone, 2,3-butanedione, and 3-penten-2-one; the cyclic terpenoid ketones with more than 10 carbon atoms are selected from one or more of damascone, ionone, irisone, menthone, and carvone.

[0016] Furthermore, the composite shell material comprises an inorganic base shell / nano-tourmaline / polydopamine, wherein the mass ratio of the inorganic base shell to the nano-tourmaline is (1-5):1, and the mass ratio of the inorganic base shell to the polydopamine is 1:(0.1-1).

[0017] Furthermore, the inorganic base shell is made of either silicon dioxide or titanium dioxide, preferably silicon dioxide.

[0018] Furthermore, the surface of the composite shell material is loaded with a metal chelate, wherein the metal is preferably copper.

[0019] Furthermore, the surface of the composite shell is loaded with metal chelates, and the metal loading accounts for 0.1wt%-10wt% of the total mass of the odor-free and environmentally friendly microcapsules.

[0020] A second aspect of this invention provides a method for preparing odor-neutralizing and environmentally friendly microcapsules, comprising the following steps:

[0021] S1: Mix nano-tourmaline, surfactant and solvent, and modify under stirring. After modification, wash and freeze dry to obtain modified nano-tourmaline.

[0022] S2: Stir and mix one or more deodorizing agents to obtain a core material mixture;

[0023] S3: Add solvent and modified nano-tourmaline obtained in step S1 to the core material mixture obtained in step S2, and stir to mix;

[0024] S4: Add the inorganic base shell precursor to the reaction system of step S3, stir and mix to obtain Pickering emulsion;

[0025] S5: Adjust the pH of the Pickering emulsion obtained in step S4 to 3-6, continue stirring, then age, filter, freeze dry, and obtain the odor-neutralizing and environmentally friendly microcapsule matrix.

[0026] S6: Disperse the odor-neutralizing and environmentally friendly microcapsule matrix obtained in step S5 in a buffer solution, add dopamine hydrochloride, process with stirring, then filter, wash, and freeze-dry.

[0027] S7: Disperse the solid powder obtained after freeze-drying in step S6 in a metal ion salt-formamide solution, and process it under stirring. After the reaction is complete, filter, wash, and freeze-dry to obtain the odor-free and environmentally friendly microcapsules.

[0028] Further, in step S1, the surfactant is a cationic surfactant, preferably at least one of hexadecyltrimethylammonium bromide, dodecyldimethylbenzylammonium chloride, and octadecyltrimethylammonium chloride.

[0029] Further, in step S1, the solvent is an aprotic solvent with a boiling point >100℃, preferably at least one of formamide, N,N-dimethylformamide, dimethylacetamide, and dimethylphosphoramide, and more preferably formamide.

[0030] Further, in step S1, the mass ratio of the nano-tourmaline to the surfactant is (1-10):1, and the mass ratio of the solvent to the surfactant is (10-40):1.

[0031] Furthermore, in step S1, the stirring speed is 400-600 rpm; the modification temperature is 100-190℃; and the modification time is 4-8 hours.

[0032] Furthermore, in step S1, the freeze-drying conditions are: vacuum drying for 4-8 hours at a temperature of -40°C to -20°C.

[0033] Furthermore, in step S2, the stirring speed is 400-600 rpm, the stirring temperature is 30-70°C, and the stirring time is 3-10 minutes.

[0034] Further, in step S3, the solvent is an aprotic solvent with a boiling point >100℃, preferably at least one of formamide, N,N-dimethylformamide, dimethylacetamide, and dimethylphosphoramide, and more preferably N,N-dimethylformamide.

[0035] Further, in step S3, the mass ratio of the core material mixture to the modified nano-tourmaline is (1-10):1, and the mass ratio of the solvent to the modified nano-tourmaline is (10-40):1.

[0036] Furthermore, in step S3, the stirring speed is 400-600 rpm, the stirring temperature is 30-60℃, and the stirring time is 4-6 hours.

[0037] Furthermore, in step S4, the inorganic base shell precursor is one of silicate ester compounds and titanate ester compounds, preferably a silicate ester compound.

[0038] Furthermore, the silicate ester compound is preferably one or more of methyl silicate, ethyl orthosilicate, tetraethyl orthosilicate, and butyl orthosilicate, and is more preferably tetraethyl orthosilicate.

[0039] Further, in step S4, the mass ratio of the core material mixture to the inorganic base shell precursor is (0.5-2):1. The stirring speed is 400-600 rpm, the stirring temperature is 30-60℃, and the stirring time is 4-6 hours.

[0040] Furthermore, in step S5, the pH can be adjusted using a dilute acid, such as dilute hydrochloric acid. The stirring speed is 400-600 rpm, the stirring temperature is 30-60℃, and the stirring time is 4-6 hours.

[0041] Further, in step S5, the aging conditions are: standing at 40-60℃ for 12-30 hours. The freeze-drying conditions are: vacuum drying at -40--20℃ for 4-8 hours.

[0042] Further, in step S6, the buffer solution is one or more of phosphate buffer, carbonate buffer, and tris(hydroxymethyl)aminomethane hydrochloride buffer (Tris buffer), preferably tris(hydroxymethyl)aminomethane hydrochloride buffer (Tris buffer).

[0043] Furthermore, in step S6, the pH value of the buffer solution is preferably 8-10.

[0044] Further, in step S6, the mass ratio of the buffer solution to the odor-neutralizing and environmentally friendly microcapsule matrix obtained in step S5 is (10-100):1.

[0045] Furthermore, in step S6, after adding dopamine hydrochloride, the mass concentration of dopamine in the reaction system is 2-10 mg / mL.

[0046] Furthermore, in step S6, the stirring speed is 100-300 rpm, the stirring temperature is 20-40℃, and the stirring time is 12-24 hours.

[0047] Furthermore, in step S6, the freeze-drying conditions are: vacuum drying for 4-8 hours at a temperature of -40°C to -20°C.

[0048] Furthermore, in step S7, the solid powder obtained after freeze-drying in step S6 is dispersed in a metal ion salt-formamide solution, which can be done by ultrasonic dispersion.

[0049] Furthermore, in step S7, the metal ion salt is preferably a copper ion salt, and more preferably anhydrous copper sulfate.

[0050] Further, in step S7, the mass ratio of the metal ion salt to formamide in the metal ion salt-formamide solution is (0.5-1.5):1.

[0051] Further, in step S7, the mass ratio of the metal ion salt-formamide solution to the solid powder obtained after freeze-drying in step S7 is (5-20):1.

[0052] Furthermore, in step S7, the stirring speed is 200-450 rpm, the processing temperature is 100-190℃, and the processing time is 2-5 hours.

[0053] Furthermore, in step S7, the freeze-drying conditions are: vacuum drying at -40°C to -20°C for 4-8 hours.

[0054] A third aspect of this invention provides a odor-neutralizing and environmentally friendly asphalt additive, comprising the following components by weight:

[0055] The above-mentioned odor-neutralizing and environmentally friendly microcapsules, 1-10 portions;

[0056] Dispersant, 1-10 parts.

[0057] Furthermore, the dispersant is one or more of dodecyl dimethyl betaine and 1-hydroxyethyl-carboxymethyl-alkyl imidazoline.

[0058] Furthermore, the dispersant and the odor-neutralizing and environmentally friendly microcapsules are stirred and mixed at room temperature at a speed of 200-400 rpm for 1-3 hours to obtain the odor-neutralizing and environmentally friendly asphalt additive.

[0059] A fourth aspect of this invention provides an odor-free and environmentally friendly asphalt, comprising the following components by weight:

[0060] Base bitumen, 100-300 parts;

[0061] The above-mentioned odor-neutralizing and environmentally friendly asphalt additive, 1-50 parts.

[0062] Further, the base asphalt is heated to 133-153℃, and the odor-free and environmentally friendly asphalt additive is added at a speed of 200-400 rpm. After stirring for 2-4 hours, the odor-free and environmentally friendly asphalt can be obtained.

[0063] Compared with the prior art, the present invention has the following advantages:

[0064] (1) The odor-neutralizing and environmentally friendly microcapsules of the present invention have a composite shell material comprising an inorganic base shell / nano-tourmaline / polydopamine, which has three functions. First, during the preparation process, nano-tourmaline serves as a template agent for microcapsule synthesis, which can maintain the stability of the core material mixed droplets. Second, during the metal ion modification process of the microcapsule composite shell material, the negative ion field released by nano-tourmaline under high temperature conditions is used to adsorb a large number of metal ions onto the surface of the microcapsule, effectively increasing the metal ion loading of the microcapsule shell material and further enhancing the smoke suppression ability of the slow-release modified microcapsules. Third, during the asphalt mixing process, under the action of high temperature, the nano-tourmaline contained inside the slow-release modified microcapsule shell material will release a negative ion field, further attracting the compounds released by the asphalt under high temperature to the vicinity of the slow-release modified microcapsules. While increasing the difficulty of volatilization of these compounds, it can make the metal ions on the surface of the microcapsule and the smoke suppression active components released by the microcapsule react with more of the above compounds, thereby effectively reducing the impact of irritating gases released from asphalt pavement on the human body.

[0065] (2) The odor-free and environmentally friendly asphalt of the present invention contains odor-free and environmentally friendly microcapsules. The surface of the composite shell material is modified with a layer of chelated metal ions. These chelated metal ions have empty orbitals. After the odor-free and environmentally friendly microcapsules enter the asphalt system, the chelated metal ions can directly accept the unshared electrons of some more active sulfur-containing and nitrogen-containing pollutants in the asphalt and form coordination bonds, thereby stably fixing the above compounds on the surface of the odor-free and environmentally friendly microcapsules, preventing them from volatilizing at high temperatures, and further rapidly reducing the content of irritating gases in asphalt fumes.

[0066] (3) The odor-free and environmentally friendly asphalt of the present invention contains odor-free and environmentally friendly microcapsules, which encapsulate the odor-free active components with low boiling points in a composite shell. These active components can be slowly released from the microcapsules during asphalt storage and construction, avoiding problems such as reduced emission reduction effect and short duration caused by the active components not reacting with the relevant components in the asphalt due to high temperature volatilization. In addition, the odor-free and environmentally friendly asphalt of the present invention contains odor-free and environmentally friendly microcapsules with small size, and their outer layer is a polydopamine film that can interact with polar molecules in asphalt and has good compatibility with asphalt. Therefore, its addition to asphalt can effectively avoid affecting the asphalt road performance.

[0067] (4) The odor-free and environmentally friendly asphalt of the present invention contains odor-free and environmentally friendly microcapsules with a fragrant aroma, and the aroma type can be adjusted according to requirements. After being added to the asphalt, it can play a role in suppressing odor during the asphalt construction process, further reducing the impact of asphalt fumes on the sensory experience of construction workers and residents around the construction road. Attached Figure Description

[0068] Figure 1 This is a scanning electron microscope image of the odor-neutralizing and environmentally friendly microcapsules obtained in Example 1. Detailed Implementation

[0069] To further illustrate the technical solution of the present invention, the present invention will be clearly and thoroughly described below in conjunction with embodiments.

[0070] The odor-neutralizing and environmentally friendly microcapsules of this invention were subjected to morphological testing using a scanning electron microscope with an accelerating voltage of 20kV. Since the microcapsule wall material is non-conductive, the samples need to be sputter-coated with gold before testing.

[0071] The odor-neutralizing and environmentally friendly microcapsules of this invention were subjected to surface elemental testing using an X-ray energy dispersive spectroscopy (EDS) instrument to confirm that metal ions were successfully modified onto the surface of the microcapsules.

[0072] The sulfides in the odor-free and environmentally friendly asphalt flue gas described in this invention are tested by gas chromatography according to the national standard GB / T 14678-1993, "Determination of Hydrogen Sulfide, Methanethiol, Dimethyl Sulfide and Dimethyl Disulfide in Air Quality".

[0073] The base asphalt used in the following examples and comparative examples is Sinopec Donghai brand No. 70 Grade A asphalt.

[0074] Example 1

[0075] S1: 40 nm nano-tourmaline, octadecyltrimethylammonium chloride and formamide were mixed in a mass ratio of 1:1:20 and stirred at 180 °C and 400 rpm for 5 hours. Then, the mixture was washed multiple times with ethanol and dried under vacuum at -30 °C for 5 hours to obtain modified nano-tourmaline for later use.

[0076] S2: Mix 2-methylundecaldehyde, cinnamaldehyde, linalool, santalol, salicylate leaf ester, geraniol acetate, 3-penten-2one, damascone, etc., and stir at 400 rpm for 10 minutes at 50°C to obtain the core material mixture.

[0077] S3: Add the modified nano-tourmaline and N,N-dimethylformamide obtained in step S1 to the reaction system of step S2. The mass ratio of the core material mixture, modified nano-tourmaline and N,N-dimethylformamide is 2:1:20. Continue stirring at 400 rpm for 5 hours at 50°C.

[0078] S4: Add tetraethyl orthosilicate to the reaction system of step S3. The mass ratio of the core material mixture to tetraethyl orthosilicate is 1:1. Continue stirring at 400 rpm for 5 hours at 50°C to obtain Pickering emulsion.

[0079] S5: Slowly add 10wt% dilute hydrochloric acid to the reaction system in step S4 using a peristaltic pump until the pH of the reaction system is 4. Continue stirring at 400 rpm for 5 hours at 50°C, then stop stirring and age at the same temperature for 24 hours. Then filter and wash the solid powder in the reaction system and vacuum dry it at -30°C for 5 hours to obtain the odor-free and environmentally friendly microcapsule matrix.

[0080] S6: Add the odor-neutralizing and environmentally friendly microcapsule matrix obtained in step S5 to a Tris buffer solution with a pH of 8.5. The mass ratio of the Tris buffer solution to the odor-neutralizing and environmentally friendly microcapsule matrix is ​​40:1. Then add dopamine hydrochloride to make the concentration of dopamine in the reaction system 3 mg / mL. Stir at 200 rpm for 12 hours at 25°C and then stop stirring. Filter and wash the bottom solid powder and vacuum dry it at -30°C for 5 hours.

[0081] S7: The solid powder obtained in step S6 is ultrasonically dispersed in a 50 wt% anhydrous copper sulfate-formamide solution. The mass ratio of the solid powder to the anhydrous copper sulfate-formamide solution is 1:10. The mixture is stirred at 400 rpm and 140°C for 2 hours. After stirring, the solid powder is filtered, washed, and freeze-dried to obtain the odor-free and environmentally friendly microcapsules. The electron micrograph is shown below. Figure 1 .

[0082] The odor-neutralizing and environmentally friendly microcapsules obtained in step S7 and dodecyl dimethyl betaine were stirred and mixed at 300 rpm for 3 hours at room temperature to obtain an odor-neutralizing and environmentally friendly asphalt additive. The mass ratio of the odor-neutralizing and environmentally friendly microcapsules to dodecyl dimethyl betaine was 1:1.

[0083] Heat 100 parts of base asphalt to 143°C, add 10 parts of the above-mentioned odor-free and environmentally friendly asphalt additive at 400 rpm, and stir for 4 hours to obtain odor-free and environmentally friendly asphalt.

[0084] Example 2

[0085] Except for step S4, where the mass ratio of tetraethyl orthosilicate to the core material mixture is 1:0.5, the rest is the same as in Example 1.

[0086] Example 3

[0087] Except that the dispersant used in the preparation of the odor-neutralizing and environmentally friendly asphalt additive is 1-hydroxyethyl-carboxymethyl-alkylimidazoline, the rest is the same as in Example 1.

[0088] Example 4

[0089] Except for step S2, in which the core material mixture is a mixture of 10-11 enal, 2-methyl-3-(4-isopropylphenyl)propanal, geraniol, menthol, benzyl salicylate, lavender acetate, 2,3-butanedione, ionone, etc., the rest is the same as in Example 1.

[0090] Example 5

[0091] Except that the mass ratio of the odor-neutralizing and environmentally friendly microcapsules to dodecyl dimethyl betaine is 3:1 when preparing the odor-neutralizing and environmentally friendly asphalt additive, the rest is the same as in Example 1.

[0092] Example 6

[0093] Except that the amount of base asphalt used in preparing the odorless and environmentally friendly asphalt is 200 parts, the rest is the same as in Example 1.

[0094] Example 7

[0095] Except that the mass ratio of the core material mixture, modified nano-tourmaline, and N,N-dimethylformamide in step S3 is 3:1:20, the rest is the same as in Example 1.

[0096] Comparative Example 1

[0097] S1: Mix 2-methylundecaldehyde, cinnamaldehyde, linalool, santalol, salicylate leaf ester, geranyl acetate, methyl nonyl ketone, menthone, etc., and stir at 400 rpm for 10 minutes at 50°C to obtain a deodorizing mixture.

[0098] The neutralized mixed solution obtained in step S1 and dodecyl dimethyl betaine were stirred and mixed at 300 rpm for 3 hours at room temperature. The mass ratio of the mixed solution to dodecyl dimethyl betaine was 1:1.

[0099] Heat 100 parts of base asphalt to 143°C, add 10 parts of the above-prepared mixture at 400 rpm, and stir for 4 hours to obtain odor-free and environmentally friendly asphalt.

[0100] Comparative Example 2

[0101] S1: 40 nm nano-tourmaline, octadecyltrimethylammonium chloride and formamide were mixed in a mass ratio of 1:1:20 and stirred at 180 °C and 400 rpm for 5 hours. Then, the mixture was washed multiple times with ethanol and dried under vacuum at -30 °C for 5 hours to obtain modified nano-tourmaline for later use.

[0102] S2: Mix 2-methylundecaldehyde, cinnamaldehyde, linalool, santalol, salicylate leaf ester, geraniol acetate, methyl nonyl ketone, menthone, etc. by mass, and stir at 400 rpm for 10 minutes at 50°C to obtain the core material mixture.

[0103] S3: Add the modified nano-tourmaline and N,N-dimethylformamide obtained in step S1 to the reaction system of step S2. The mass ratio of the core material mixture, modified nano-tourmaline and N,N-dimethylformamide is 2:1:20. Continue stirring at 400 rpm for 5 hours at 50°C.

[0104] S4: Add tetraethyl orthosilicate to the reaction system of step S3. The mass ratio of the core material mixture to tetraethyl orthosilicate is 1:1. Continue stirring at 400 rpm for 5 hours at 50°C to obtain Pickering emulsion.

[0105] S5: Slowly add 10wt% dilute hydrochloric acid to the reaction system in step S4 using a peristaltic pump until the pH of the reaction system is 4. Continue stirring at 400 rpm for 5 hours at 50°C, then stop stirring and age at the same temperature for 24 hours. Then filter and wash the solid powder in the reaction system and vacuum dry it at -30°C for 5 hours to obtain the odor-free and environmentally friendly microcapsule matrix.

[0106] S6: Add the odor-neutralizing and environmentally friendly microcapsule matrix obtained in step S5 to a Tris buffer solution with a pH of 8.5. The mass ratio of the Tris buffer solution to the odor-neutralizing and environmentally friendly microcapsule matrix is ​​40:1. Then, add dopamine hydrochloride to make the concentration of dopamine in the reaction system 3 mg / mL. Stir at 200 rpm for 12 hours at 25°C and then stop stirring. Filter and wash the bottom solid powder and vacuum dry it at -30°C for 5 hours.

[0107] The solid powder obtained in step S6 and dodecyl dimethyl betaine were stirred and mixed at 300 rpm for 3 hours at room temperature to obtain a odor-neutralizing and environmentally friendly asphalt additive. The mass ratio of the odor-neutralizing and environmentally friendly microcapsules to dodecyl dimethyl betaine was 1:1.

[0108] Heat 100 parts of base asphalt to 143°C, add 10 parts of the above-mentioned odor-free and environmentally friendly asphalt additive at 400 rpm, and stir for 4 hours to obtain odor-free and environmentally friendly asphalt.

[0109] Comparative Example 3

[0110] The preparation of the odor-free and environmentally friendly microcapsules is the same as in Example 1, except that when preparing the odor-free and environmentally friendly asphalt, 100 parts of base asphalt are heated to 143°C, and 5 parts of odor-free and environmentally friendly microcapsules are added at a speed of 400 rpm. After stirring for 4 hours, the odor-free and environmentally friendly asphalt is obtained.

[0111] Comparative Example 4

[0112] S1: Mix 2-methylundecaldehyde, cinnamaldehyde, linalool, santalol, salicylate leaf ester, geraniol acetate, 3-penten-2one, damascone, etc. by mass, and stir at 400 rpm for 10 minutes at 50°C to obtain the core material mixture.

[0113] S2: Add octadecyltrimethylammonium chloride and N,N-dimethylformamide to the reaction system of step S1. The mass ratio of the core material mixture, hexadecyltrimethylammonium bromide and N,N-dimethylformamide is 2:1:20. Continue stirring at 400 rpm for 5 hours at 50°C.

[0114] S3: Add tetraethyl orthosilicate to the reaction system of step S2. The mass ratio of the core material mixture to tetraethyl orthosilicate is 1:1. Continue stirring at 400 rpm for 5 hours at 50°C to obtain Pickering emulsion.

[0115] S4: Slowly add 10wt% dilute hydrochloric acid to the reaction system in step S3 using a peristaltic pump until the pH of the reaction system is 4. Continue stirring at 400 rpm for 5 hours at 50°C, then stop stirring and age at the same temperature for 24 hours. Then filter and wash the solid powder in the reaction system and vacuum dry it at -30°C for 5 hours to obtain the odor-free and environmentally friendly microcapsule matrix.

[0116] S5: Add the odor-neutralizing and environmentally friendly microcapsule matrix obtained in step S4 to a Tris buffer solution with a pH of 8.5. The mass ratio of the Tris buffer solution to the odor-neutralizing and environmentally friendly microcapsule matrix is ​​40:1. Then add dopamine hydrochloride to make the concentration of dopamine in the reaction system 3 mg / mL. Stir at 200 rpm for 12 hours at 25°C and then stop stirring. Filter and wash the bottom solid powder and vacuum dry it at -30°C for 5 hours.

[0117] S6: The solid powder obtained in step S5 is ultrasonically dispersed in a 50wt% anhydrous copper sulfate-formamide solution. The mass ratio of the solid powder to the anhydrous copper sulfate-formamide solution is 1:10. The mixture is stirred and reacted at 400 rpm and 140°C for 2 hours. After stirring, the solid powder is filtered, washed, and freeze-dried to obtain the odor-free and environmentally friendly microcapsules.

[0118] The odor-neutralizing and environmentally friendly microcapsules obtained in step S6 and dodecyl dimethyl betaine were stirred and mixed at 300 rpm for 3 hours at room temperature to obtain an odor-neutralizing and environmentally friendly asphalt additive. The mass ratio of the odor-neutralizing and environmentally friendly microcapsules to dodecyl dimethyl betaine was 1:1.

[0119] Heat 100 parts of base asphalt to 143°C, add 10 parts of the above-mentioned odor-free and environmentally friendly asphalt additive at 400 rpm, and stir for 4 hours to obtain odor-free and environmentally friendly asphalt.

[0120] Test case

[0121] Sulfides are the main cause of the pungent odor of asphalt fumes. The odor-free and environmentally friendly asphalts prepared in Examples 1-7 and Comparative Examples 1-4 were stored at 143°C for 0 days, 7 days, and 30 days, respectively. Then, an equal mass of the stored asphalt was transferred to a sealed container and the fumes were enriched at 163°C and 300 rpm for 4 hours. After enrichment, the gas in the sealed container was extracted and tested by gas chromatography. The data are shown in Table 1 below.

[0122] Table 1 Sulfide Content Test

[0123]

[0124] It should be emphasized that the above-mentioned content is only a specific embodiment of the present invention and should not be construed as limiting the present invention to the above description in specific implementation. For those skilled in the art, any simple deductions and improvements made without departing from the spirit and principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A clean-taste, environmentally friendly microcapsule, characterized by: The net taste environment-friendly microcapsule comprises a composite shell material and a core material, wherein the composite shell material comprises an inorganic base layer shell / nano-tomarite / polydopamine, and the core material comprises one or more net taste agents; the surface of the shell material is loaded with a metal chelate; The net taste agent is one or more of aldehydes, alcohols, esters and ketones; The material of the inorganic base layer shell is selected from one or more of silicon dioxide and titanium dioxide; The surface of the composite shell material is loaded with a metal chelate, wherein the metal is copper; The net taste environment-friendly microcapsule is prepared by the following method, comprising: S1: mixing nano-tomarite, a surfactant and a solvent, modifying under stirring, washing after modification, freeze-drying to obtain modified nano-tomarite; S2: stirring and mixing one or more net taste agents to obtain a core material mixture; S3: adding a solvent and the modified nano-tomarite obtained in step S1 to the core material mixture obtained in step S2, and stirring and mixing; S4: adding an inorganic base layer shell precursor to the reaction system in step S3, stirring and mixing to obtain a Pickering emulsion; S5: adjusting the pH value of the Pickering emulsion obtained in step S4 to 3-6, continuing to stir, then aging, filtering, freeze-drying to obtain a net taste environment-friendly microcapsule base; S6: dispersing the net taste environment-friendly microcapsule base obtained in step S5 in a buffer solution, adding dopamine hydrochloride, stirring and treating, then filtering, washing and freeze-drying; S7: dispersing the solid powder obtained after freeze-drying in step S6 in a copper ion salt-formamide solution, stirring and treating, filtering, washing and freeze-drying after the reaction is completed, to obtain the net taste environment-friendly microcapsule.

2. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: The particle size of the net taste environment-friendly microcapsule is 1-5 μm.

3. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: The mass ratio of the composite shell material to the core material of the net taste environment-friendly microcapsule is 1:(0.5-2).

4. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: The net taste agent simultaneously comprises aldehydes, alcohols, esters and ketones.

5. The tasteless environment-friendly microcapsule according to claim 1 or 4, characterized in that: The aldehydes are selected from one or more of aliphatic aldehydes with more than 10 carbon atoms and aromatic aldehydes with more than 7 carbon atoms; the aliphatic aldehyde with more than 10 carbon atoms is selected from one or more of 2-methyl undecanal and 10-undecenal; the aromatic aldehyde with more than 7 carbon atoms is selected from one or more of benzaldehyde, cinnamyl aldehyde, o-methoxy-p-methyl benzaldehyde, 2-methyl-3-(4-isopropyl phenyl) propionaldehyde and 2-methyl-3-(3,4-methylene dioxy phenyl) propionaldehyde; The alcohols are selected from one or more of terpene alcohols with more than 10 carbon atoms and cyclic terpene alcohols with more than 10 carbon atoms; the terpene alcohol with more than 10 carbon atoms is selected from one or more of geraniol, linalool, citronellol, ionol, hyacinth alcohol, myrcenol, lavandulol and nerolidol; the cyclic terpene alcohol with more than 10 carbon atoms is selected from one or more of menthol, terpinen-4-ol, isoborneol and cedrol; The esters are selected from one or more of aromatic esters with carbon number greater than 12 and terpene esters with carbon number greater than 11; the aromatic esters with carbon number greater than 12 are selected from one or more of isopentyl benzoate, benzyl benzoate, isopentyl salicylate, benzyl salicylate, linalyl salicylate, benzyl cinnamate, phenethyl cinnamate; the terpene esters with carbon number greater than 11 are selected from one or more of myrcene formate, myrcene acetate, myrcene propionate, nerolidol acetate, linalyl formate, linalyl propionate, lavandulat acetate, citronellal butyrate; The ketones are selected from one or more of aliphatic ketones with carbon number greater than 3 and cyclic terpene ketones with carbon number greater than 10; the aliphatic ketones with carbon number greater than 3 are selected from one or more of 3-hydroxy-2-butanone, 2,3-butanedione, 3-penten-2-one; the cyclic terpene ketones with carbon number greater than 10 are selected from one or more of damascone, ionone, irisone, menthone, carvone.

6. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: The composite shell material comprises an inorganic base layer shell / nano-tomaraine / polydopamine, wherein the mass ratio of the inorganic base layer shell to nano-tomaraine is (1-5):1, and the mass ratio of the inorganic base layer shell to polydopamine is 1:(0.1-1).

7. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: The material of the inorganic base layer shell is silicon dioxide.

8. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: The metal loading amount on the surface of the composite shell material accounts for 0.1wt%-10wt% of the total mass of the odorless and environmentally friendly microcapsules.

9. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: In step S1, the surfactant is a cationic surfactant, and the solvent is an aprotic solvent with a boiling point >100℃. And / or, in step S1, the mass ratio of the nano-tomaraine to the surfactant is (1-10):1, and the mass ratio of the solvent to the surfactant is (10-40):

1.

10. The tasteless environment-friendly microcapsule according to claim 9, characterized in that: In step S1, the surfactant is at least one of cetyltrimethylammonium bromide, dodecyl dimethyl benzyl ammonium chloride, and octadecyl trimethyl ammonium chloride; and the solvent is at least one of formamide, N,N-dimethylformamide, dimethylacetamide, and dimethylphosphoryl amide.

11. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: In step S1, the stirring speed is 400-600 revolutions per minute; the modification temperature is 100-190℃, and the modification time is 4-8 hours. And / or, in step S2, the stirring speed is 400-600 revolutions per minute, the stirring temperature is 30-70℃, and the stirring time is 3-10 minutes. And / or, in step S3, the stirring speed is 400-600 revolutions per minute, the stirring temperature is 30-60℃, and the stirring time is 4-6 hours. And / or, in step S4, the stirring speed is 400-600 revolutions per minute, the stirring temperature is 30-60℃, and the stirring time is 4-6 hours. And / or, in step S5, the stirring speed is 400-600 revolutions per minute, the stirring temperature is 30-60℃, and the stirring time is 4-6 hours. And / or, in step S6, the stirring speed is 100-300 revolutions per minute, the stirring temperature is 20-40℃, and the stirring time is 12-24 hours. And / or, in step S7, the stirring speed is 200-450 rpm, the processing temperature is 100-190℃, and the processing time is 2-5 hours.

12. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: In step S3, the solvent is an aprotic solvent with a boiling point >100℃. And / or, in step S3, the mass ratio of the core material mixture to the modified nanometer tomamlyn is (1-10):1, and the mass ratio of the solvent to the modified nanometer tomamlyn is (10-40):

1.

13. The tasteless environmentally friendly microcapsule according to claim 12, characterized in that: In step S3, the solvent is at least one of formamide, N,N-dimethylformamide, dimethylacetamide, and dimethylphosphoramide.

14. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: In step S4, the inorganic base layer shell precursor is one of silicate compounds and titanate compounds. And / or, the mass ratio of the core material mixture to the inorganic base layer shell precursor is (0.5-2):

1.

15. The tasteless environmentally friendly microcapsule according to claim 14, characterized in that: The silicate compound is one or more of methyl silicate, ethyl orthosilicate, tetraethyl orthosilicate, and butyl orthosilicate.

16. The tasteless environment-friendly microcapsule according to claim 1, characterized in that: In step S6, the buffer solution is one or more of phosphate buffer, carbonate buffer, and tris-hydroxymethyl aminomethane hydrochloride buffer. And / or, the mass ratio of the buffer solution to the odorless environment-friendly microcapsule matrix obtained in step S5 is (10-100):

1.

17. The tasteless environmentally friendly microcapsule according to claim 16, characterized in that: The pH value of the buffer solution is 8-10.

18. The tasteless and environmentally friendly microcapsule according to claim 1, wherein: In step S6, after adding dopamine hydrochloride, the mass concentration of dopamine in the reaction system is 2-10 mg / mL.

19. The tasteless and environmentally friendly microcapsule according to claim 1, wherein: In step S7, the metal copper ion salt is anhydrous copper sulfate. And / or, in the metal copper ion salt-formamide solution, the mass ratio of the metal copper ion salt to formamide is (0.5-1.5):

1.

20. A deodorized environmentally friendly asphalt additive characterized by: By weight, it includes the following components: The odorless environment-friendly microcapsule according to any one of claims 1-19; Dispersant, 1-10 parts.

21. The tasteless environmentally friendly asphalt additive according to claim 20, characterized in that: The dispersant is one or more of dodecyl dimethyl betaine and 1-hydroxyethyl-carboxymethyl-alkyl imidazoline.

22. An odorless environment-friendly asphalt, by weight, including the following components: Base asphalt, 100-300 parts; The odorless environment-friendly asphalt additive according to any one of claims 20-21, 1-50 parts.

Images