CN113480939A

CN113480939A - Ultraviolet absorber, preparation method thereof and pavement maintenance coating containing ultraviolet absorber

Info

Publication number: CN113480939A
Application number: CN202110529362.XA
Authority: CN
Inventors: 马融; 左连滨; 杨磊; 池育源
Original assignee: Beijing Huajian Shenghe Technology Development Co ltd; Research Institute of Highway Ministry of Transport
Current assignee: Beijing Huajian Shenghe Technology Development Co ltd; Research Institute of Highway Ministry of Transport
Priority date: 2021-05-14
Filing date: 2021-05-14
Publication date: 2021-10-08

Abstract

The invention provides an ultraviolet absorbent, a preparation method thereof and a pavement maintenance coating containing the ultraviolet absorbent. The ultraviolet absorbent comprises the following components: the asphalt emulsion comprises a stabilizer and polymer microspheres, wherein the polymer microspheres comprise a carrier and an anti-aging agent; the mass ratio of the emulsified asphalt to the polymer microspheres is 1: 0.05-2, and preferably 1: 0.1-1. The ultraviolet absorbent can well slow down the aging effect of ultraviolet rays in sunlight on asphalt pavements, and prolong the service life of roads. And can realize spraying on time as required, and is economical and convenient. The preparation method of the ultraviolet absorbent is simple and easy to implement, the raw materials are easy to obtain, and the ultraviolet absorbent is suitable for mass production.

Description

Ultraviolet absorber, preparation method thereof and pavement maintenance coating containing ultraviolet absorber

Technical Field

The invention relates to an ultraviolet absorbent, a preparation method thereof and a pavement maintenance coating containing the ultraviolet absorbent, in particular to an ultraviolet absorbent for asphalt pavements in low latitude and high radiation areas, a preparation method thereof and a pavement maintenance coating containing the ultraviolet absorbent.

Background

Because the environment of the pavement is greatly different, in low-latitude and high-radiation areas, the ultraviolet radiation intensity is high, the ultraviolet light can cause the asphalt surface layer to be further aged, the asphalt becomes dry, hard and crisp, and the asphalt pavement is easy to form temperature shrinkage cracks, thereby generating cracks. When the asphalt pavement is in rain, water enters from cracks and stays in the asphalt surface layer, so that the asphalt surface layer is damaged by water, and asphalt falls off from the surface of aggregate in serious conditions, so that the generation of diseases such as cracks, looseness, peeling, pits and the like of the asphalt pavement is caused, and the pavement performance and the service life of the asphalt pavement are greatly reduced.

Asphalt, as an organic polymer material, is susceptible to aging under the action of heating or natural environmental factors. At present, the antiager AW, BLE and ultraviolet screening agent are added into asphalt at home and abroad. There are a number of uv resistant additives on the market, for example: bentonite, inorganic nanoparticles, and the like. The addition of the additives can effectively slow down the molecular breakage in the asphalt and reduce the occurrence of oxidation reaction. However, the ultraviolet-resistant additive is added to the asphalt material, and then the mixture is mixed and paved into an asphalt pavement. This type of technology can only be used for new roads, and for existing roads, functional reconstruction is not possible.

Generally, the ultraviolet rays are injected into the asphalt to a depth of about 0.1mm, and the influence of the ultraviolet rays on the aging of the asphalt takes place at about 1mm of the surface of the asphalt in consideration of the inward diffusion of asphalt molecules after aging. Due to gaps existing in the asphalt pavement, the influence of strong ultraviolet rays on the asphalt pavement can reach about 1 cm. In addition, the application region of the ultraviolet aging resistant asphalt mixture has limitations, and the ultraviolet aging resistant asphalt mixture is mainly applied to low-latitude and high-radiation regions. The ultraviolet radiation time is not all-weather, the economy of all large-scale paving is poor, the additive has influence on the asphalt material, and the pavement performance of the functional pavement is to be verified.

Citation 1 discloses a coating material for resisting ultraviolet aging of asphalt pavement and a preparation method thereof, wherein the coating material comprises the following components in parts by weight: 2-3 parts of nano cerium dioxide, 70-80 parts of epoxy resin, 15-20 parts of organic solvent, 0.1-0.2 part of defoaming agent and 0.8-0.9 part of dispersing agent; the epoxy resin is firstly dissolved in a certain amount of organic solvent to prepare polymer binder, then the nano iron dioxide is dispersed in the polymer binder, and simultaneously a certain amount of dispersant and defoamer are added and stirred uniformly to prepare the nano iron dioxide modified epoxy resin. The ultraviolet aging resistant coating material for the asphalt pavement is coated after being blended by a plurality of chemical reagents, the corrosion degree of the asphalt pavement needs to be verified, the adhesion effect between the coating material and the asphalt pavement is poor, and the coating material can not be repaired after being heated again after epoxy resin is cured.

Citation 2 discloses a heat shielding coating and a method for producing the same. The heat shielding coating comprises the following raw material components: the coating mainly comprises a film forming substance, a reflection functional material, a color-mixing functional pigment, a heat-insulation functional material, an ultraviolet-resistant functional material, a diluent, a defoaming agent, a leveling agent, a curing agent, a low-temperature toughening agent and anti-skid particles. The used anti-ultraviolet functional material is anatase TiO₂Ultraviolet absorbent UV-1577, ultraviolet absorbent UV-531 and ultraviolet absorbent UV-9. The additive used in the whole process is too much, the influence of the coating mixed by various additives on the asphalt property and components is to be verified, the price is high, the economy is poor, the coating without asphalt cannot play a role in repairing the pavement microcracks, and the preparation process of the coating is too complex.

Cited documents:

cited document 1: CN102775879A

Cited document 2: CN109593436A

Disclosure of Invention

Problems to be solved by the invention

In view of the technical problems in the prior art, the invention firstly provides the ultraviolet absorbent which can be selectively sprayed on the surface of the road which is easy to be subjected to ultraviolet ageing according to seasons and climatic conditions, so that the ultraviolet irradiation can be effectively blocked and slowed down, the ageing resistance of the asphalt pavement can be effectively improved, and the service life of the road can be prolonged.

Furthermore, the invention also provides a preparation method of the ultraviolet absorbent, which is simple and feasible, has easily obtained raw materials and is suitable for mass production.

Means for solving the problems

The invention provides an ultraviolet absorbent, which comprises the following components:

an emulsified asphalt, said emulsified asphalt comprising a stabilizer, and

polymeric microspheres comprising a carrier and an anti-aging agent; wherein,

the mass ratio of the emulsified asphalt to the polymer microspheres is 1: 0.05-2, preferably 1: 0.1-1.

The ultraviolet absorbent comprises an asphalt base, an emulsifier, a stabilizer and water, wherein the emulsifier is preferably added in an amount of 0.1-5%, preferably 0.5-4%, based on 100% of the total mass of the asphalt base and the water; the addition amount of the stabilizer is 0.1-3%, preferably 0.5-3%.

The ultraviolet absorber provided by the invention is characterized in that the mass ratio of the asphalt matrix to the water is 0.5-2: 1, preferably 0.8-1.5: 1.

The ultraviolet absorber according to the present invention, wherein the stabilizer comprises an organic stabilizer, preferably, the organic stabilizer comprises a cellulose-based compound.

The ultraviolet absorber according to the present invention, wherein the emulsifier comprises a nonionic emulsifier;

preferably, the nonionic emulsifier comprises one or a combination of more than two of polyoxyethylene alkylolamides, alkylphenol ethoxylates, fatty alcohol ethoxylates, fatty amine ethoxylates, fatty acid polyoxyethylene esters, alkyl alcohol polyoxyethylene ethers, block polyoxyethylene-polyoxypropylene ethers, propylene glycol polyoxyethylene polyoxypropylene ethers and the like.

The ultraviolet absorber of the present invention, wherein the polymer microspheres comprise a carrier, an anti-aging agent and water; preferably, the addition amount of the carrier is 0.5-5% by taking the total mass of water as 100%; the addition amount of the anti-aging agent is 5-20%.

The ultraviolet absorber provided by the invention is characterized in that the mass ratio of the carrier to the anti-aging agent is 1: 0.5-15.

The ultraviolet absorbent according to the present invention, wherein the carrier comprises one or a combination of two or more of collagen, gelatin, and agar; and/or

The anti-aging agent comprises one or the combination of more than two of phosphate sodium salt, polytetrafluoroethylene phenyl salicylate, hexamethylphosphoric triamide and resorcinol monobenzoate.

The invention also provides a preparation method of the ultraviolet absorbent, which comprises the following steps:

a step of preparing emulsified asphalt;

preparing polymer microspheres;

and mixing the emulsified asphalt and the polymer microspheres.

The invention also provides a pavement maintenance coating comprising the ultraviolet absorber according to the invention.

ADVANTAGEOUS EFFECTS OF INVENTION

The ultraviolet absorbent can well slow down the aging effect of ultraviolet rays in sunlight on asphalt pavements, and prolong the service life of roads. And can realize spraying on time as required, and is economical and convenient.

The preparation method of the ultraviolet absorbent is simple and easy to implement, the raw materials are easy to obtain, and the ultraviolet absorbent is suitable for mass production.

Detailed Description

The present invention will be described in detail below. The technical features described below are explained based on typical embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples. It should be noted that:

in the present specification, the numerical range represented by "numerical value a to numerical value B" means a range including the end point numerical value A, B.

In the present specification, "plural" in "plural", and the like means a numerical value of 2 or more unless otherwise specified.

In this specification, the terms "substantially", "substantially" or "substantially" mean an error of less than 5%, or less than 3% or less than 1% as compared to the relevant perfect or theoretical standard.

In the present specification, "%" denotes mass% unless otherwise specified.

In the present specification, the meaning of "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

In this specification, "optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

In the present specification, reference to "some particular/preferred embodiments," "other particular/preferred embodiments," "embodiments," and the like, means that a particular element (e.g., feature, structure, property, and/or characteristic) described in connection with the embodiment is included in at least one embodiment described herein, and may or may not be present in other embodiments. In addition, it is to be understood that the described elements may be combined in any suitable manner in the various embodiments.

In the present specification, the meaning of "normal temperature", "room temperature", and the like may be 10 to 40 ℃.

First aspect

The present invention first provides an ultraviolet absorber, which comprises:

an emulsified asphalt, said emulsified asphalt comprising a stabilizer, and

the polymer microspheres comprise a carrier and an anti-aging agent; wherein,

The ultraviolet absorbent can effectively slow down the entry of oxygen and the volatilization of light components of the asphalt during the irradiation of ultraviolet light, and slow down the photo-oxidative aging rate of the asphalt surface layer. In addition, the ultraviolet absorbent of the invention does not need to be paved on a large scale when a new road surface is built, and a special road section is selected and sprayed on the surface of the road before the time of strongest ultraviolet illumination time all the year around. The product is ready for use, convenient to use and good in economical efficiency.

< emulsified asphalt >

The ultraviolet absorber of the present invention comprises emulsified asphalt. In some specific embodiments, the emulsified asphalt comprises an asphalt base, an emulsifier, a stabilizer and water, wherein the emulsifier is added in an amount of 0.1-5%, preferably 0.5-4%, based on 100% of the total mass of the asphalt base and the water; the addition amount of the stabilizer is 0.1-3%, preferably 0.5-3%.

In some specific embodiments, the mass ratio of the asphalt base to the water is 0.5 to 2:1, for example: 0.7:1, 0.9:1, 1:1, 1.1:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, and so forth. When the mass ratio of the asphalt base and water is within the range of the present application, the ultraviolet absorber of the present application is more easily prepared. Preferably, the mass ratio of the asphalt base and water in the present application may be 0.7 to 1.5:1, more preferably 0.8 to 1.2:1, in view of stability and ease of spraying. In the present invention, when the amount of the asphalt base is too high, the fine particles of the asphalt base are closely adhered to each other, and are easily adhered to each other, and thus are not completely emulsified. If the amount of the asphalt base is too low, the emulsified asphalt may not exert the technical properties of the asphalt base well. When the mass of the asphalt matrix and the water is 0.5-2: 1, particularly 0.7-1.5: 1, the prepared ultraviolet absorbent is suitable for spraying and has good stability.

The present invention is not particularly limited to the asphalt base, and may be any asphalt source material commonly used in the art. For example: road petroleum asphalt, modified asphalt and the like.

Generally, the road petroleum asphalt includes one or a combination of two or more of 70# to 200# road petroleum asphalt and the like. The modified asphalt comprises: one or the combination of more than two of SBS modified asphalt, rubber asphalt, natural asphalt modified asphalt, high viscosity modified asphalt and the like.

Further, in the present invention, the stabilizer is added in an amount of 0.1 to 3%, preferably 0.3 to 3%, based on 100% by mass of the total mass of the asphalt base and water, for example: 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%, 2.8%, etc. The inventor of the invention finds that when the addition amount of the stabilizer is 0.1-3%, the oversize residue of the prepared emulsified asphalt is reduced along with the increase of the dosage of the stabilizer, which indicates that the fineness of the emulsified asphalt is changed, the asphalt matrix is completely emulsified, and the stability of the emulsified asphalt matrix for 5 days is improved. However, when the amount of the stabilizer is used to a certain extent, the increase in stability is limited, and the use of an excessive amount of the stabilizer increases the cost. Therefore, in the invention, the addition amount of the stabilizer is 0.1-3%.

Further, the stabilizer of the present invention includes an organic stabilizer, and by using the organic stabilizer, the effects of salt resistance, acid resistance, calcium resistance, high temperature resistance, weather resistance, and ultraviolet, radiation, and aging resistance of the ultraviolet absorber of the present invention can be improved. Preferably, the organic stabilizer comprises a cellulose-based compound.

Polyanionic cellulose (PAC) can be selected as the cellulose-based compound of the present invention. The polyanionic cellulose has higher substitution degree and substitution uniformity, shorter molecular chain and more stable molecular structure, thereby having better salt resistance, acid resistance, calcium resistance, high temperature resistance and the like and enhancing the solubility. The invention can make the two-phase system of the polymer microsphere and the emulsified asphalt exist stably by using the polyanionic cellulose. And can make the ultraviolet absorber of the invention have excellent weather resistance and ultraviolet resistance, radiation resistance and aging performance.

Further, in the invention, the addition amount of the emulsifier is 0.1-5%, preferably 0.5-4%, based on 100% of the total mass of the asphalt matrix and the water; for example: 0.2%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%, 2.8%, 3%, 3.2%, 3.5%, 3.8%, 4%, 4.2%, 4.5%, 4.8%, etc. In the invention, as the dosage of the emulsifier is increased, the oversize residue of the prepared emulsified asphalt is reduced, which shows that the fineness of the emulsified asphalt is better, the asphalt matrix is completely emulsified, and the stability is better. However, when the amount of the emulsifier is used to a certain extent, the increase of the stability is limited, and the cost is increased by using excessive emulsifier; however, the required emulsified asphalt cannot be obtained even with too little emulsifier, and therefore, the amount of the emulsifier added may be 0.1 to 5% in the present invention.

Further, in the present invention, the emulsifier includes a nonionic emulsifier. Compared with cationic emulsifiers and anionic emulsifiers, the nonionic emulsifiers used in the invention have better adaptability to anti-aging agents in polymer microspheres. The pH value range of the nonionic surfactant is wider, and the nonionic surfactant does not exist in an ionic state in a solution, so that the nonionic surfactant is high in stability and is not easily influenced by the existence of strong electrolyte.

Further, the nonionic emulsifier of the present invention is not particularly limited, and may be some nonionic emulsifiers commonly used in the art. Specifically, the nonionic emulsifier may be one or a combination of two or more of polyoxyethylene alkylolamides (for example, lauryl diethanol amide, fatty acyl diethanol amide, and the like), alkylphenol ethoxylates, fatty alcohol-polyoxyethylene ethers, fatty amine-polyoxyethylene ethers, fatty acid-polyoxyethylene esters, alkyl alcohol-polyoxyethylene ethers, block polyoxyethylene-polyoxypropylene ethers, propylene glycol polyoxyethylene-polyoxypropylene ethers, and the like.

< polymeric microspheres >

Bitumen and water are immiscible liquids and if the bitumen is sheared into fine particles by a mechanically strong shearing action, the fine particles are uniformly dispersed in the water to form a bitumen emulsion. Emulsified bitumen is an unstable two-phase system. If the storage stability of the emulsified asphalt is to be maintained, the free energy of the two-phase interface of the asphalt and the water must be reduced to achieve thermodynamic equilibrium and meet the energy minimum principle. When a large amount of electrolyte is added into the emulsified asphalt, the emulsion breaking speed of the emulsion is increased.

Emulsified bitumen is a thermodynamically unstable structure of water-in-oil or oil-in-water. The invention takes the polymer microspheres as the carrier and can disperse the anti-aging agent on the carrier of the polymer microspheres. The ultraviolet absorbent with ultraviolet aging resistance and maintenance integration can be prepared after the polymer microspheres are mixed with the emulsified asphalt.

In some specific embodiments, the polymer microspheres comprise a carrier, an anti-aging agent and water, and the anti-aging agent is adsorbed on the carrier at a microscopic scale by adding the anti-aging agent to a carrier solution. Preferably, the carrier is added in an amount of 0.5 to 5% based on 100% of the total mass of water, for example: 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, etc.; the addition amount of the anti-aging agent is 5-20%, for example: 7%, 9%, 11%, 13%, 15%, 17%, 19%, etc. When the content of the carrier and the aging inhibitor is within the range of the present application, the preparation of the polymer microspheres is facilitated and the obtained ultraviolet absorber is excellent in performance.

The invention attaches the anti-aging agent to the carrier to obtain the polymer microsphere, and then the polymer microsphere is mixed with the emulsified asphalt. The polymer microspheres enable the anti-aging agent not to directly react with the emulsified asphalt, and the polymer microspheres and the emulsified asphalt can stably exist in a two-phase form after being mixed.

Further, in the invention, the mass ratio of the carrier to the anti-aging agent is 1: 0.5-15, such as: 1:1.5, 1:2, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, etc.; when the mass ratio of the carrier to the anti-aging agent is 1: 0.5-15, the ultraviolet absorber with more excellent performance can be obtained.

The specific composition of the carrier in the present invention is not particularly limited, and may be any of those commonly used in the art. Specifically, the carrier comprises one or more of collagen, gelatin and agar.

In addition, the specific composition of the antioxidant of the present invention is not particularly limited, and may be some antioxidants commonly used in the art. Specifically, the antiaging agent of the invention may be one or a combination of two or more of a sodium phosphate salt, a phenyl polytetrafluoroethylene salicylate, hexamethylphosphoric triamide, resorcinol monobenzoate, and the like, and the sodium phosphate salt is preferably used. Furthermore, the sodium phosphate has excellent acid and alkali resistance, high temperature resistance and the like, and is an anti-aging agent with good ultraviolet shielding effect.

Second aspect of the invention

A second aspect of the present invention provides a method for preparing the ultraviolet absorber according to the present invention, which comprises the steps of:

a step of preparing emulsified asphalt;

preparing polymer microspheres;

and mixing the emulsified asphalt and the polymer microspheres.

< step of preparing emulsified asphalt >

The step of preparing the emulsified asphalt of the present invention may include:

dissolving a stabilizer and an emulsifier in water to prepare a soap solution;

and adding the soap solution into a colloid mill, shearing and stirring, and emulsifying to obtain the emulsified asphalt.

In some specific embodiments, the step of preparing the emulsified asphalt of the present invention may include the steps of:

1. weighing a certain amount of water according to a certain proportion, heating, adding a stabilizer to enable the stabilizer to be dissolved after swelling, adding an emulsifier, and uniformly stirring to prepare the soap solution.

2. Continuously and circularly preheating the emulsifying machine with water in the colloid mill, and fully preheating. The purpose of adding water is to enable the colloid mill to reach a certain temperature, the colloid mill equipment does not have a heating function, better emulsification effect can be achieved when the colloid mill is prepared at a certain temperature, and because the emulsified asphalt is an extremely unstable system and is easily affected by temperature and environment, emulsion breaking is easy to achieve. And (3) adding the soap solution obtained in the step (1) into a colloid mill, shearing and stirring to ensure the shearing effect of the emulsifier and various auxiliaries. Then slowly adding the asphalt matrix and the soap solution, and shearing and stirring in a colloid mill to emulsify.

3. And opening a valve of the colloid mill to flow out the prepared emulsified asphalt, sealing by using a preservative film and defoaming.

In some specific embodiments, in the step 1, the heating temperature is 70 to 90 ℃, and when the heating temperature is 70 to 90 ℃, the dissolution of the stabilizer is facilitated.

In some specific embodiments, in the step 2, the temperature of the water is 60-80 ℃, and the shearing and stirring time of the soap liquid is 20-40 s. In addition, in order to avoid granular sensation of the asphalt matrix, the emulsifying time is 1-5 min, and the emulsifying temperature is 120-160 ℃.

In some specific embodiments, in the step 3, the defoaming temperature is 40-70 ℃, and the defoaming time is 0.1-1 hour.

< step of preparing Polymer microspheres >

The steps of the present invention for preparing polymeric microspheres may comprise: and dissolving the carrier and the anti-aging agent in water to obtain the polymer microsphere emulsion.

In some specific embodiments, the preparation method comprises the steps of: dissolving the carrier in water, adding an anti-aging agent, and uniformly mixing to obtain the polymer microsphere emulsion, specifically, uniformly mixing at room temperature.

< mixing >

And uniformly mixing the emulsified asphalt and the polymer microsphere emulsion to obtain the ultraviolet absorbent. Specifically, the mixture may be stirred uniformly after being mixed at room temperature.

Third aspect of the invention

In a third aspect of the invention there is provided a pavement maintenance coating comprising the ultraviolet absorber of the first aspect of the invention.

The pavement maintenance coating can effectively slow down the entry of oxygen and the volatilization of light components of asphalt during ultraviolet irradiation, and slow down the photo-oxidation aging rate of an asphalt surface layer. The method does not need to be paved on a large scale when a new road surface is built, a special road section is selected, and the special road section is sprayed on the surface of the road before the time when the ultraviolet light illumination time is strongest all year round. Convenient use and good economical efficiency.

Examples

Embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.

Polyanionic cellulose (PAC), manufacturer: hebei Yanxing chemical Co., Ltd.

Asphalt matrix: road petroleum asphalt No. 90 grade A is adopted.

Sodium phosphate, manufacturer: xianhao Tian biological engineering Co., Ltd.

Example 1

1. Preparing emulsified asphalt: the dosage of the nonionic emulsifier lauroyl diethanol amine is 1.8 percent based on the total mass of the asphalt substrate and the water being 100 percent, wherein the mass ratio of the asphalt substrate to the water is 1:1.

(1) Heating the weighed water to 80 ℃, adding 0.8 percent of polyanionic cellulose (PAC) by taking the total mass of the asphalt substrate and the water as 100 percent, and continuously stirring to ensure that the polyanionic cellulose is firstly swelled and then dissolved. Adding non-ionic emulsifier lauroyl diethanol amine according to the amount, and stirring uniformly to obtain the soap solution.

(2) Continuously circulating and preheating water with the temperature of about 70 ℃ in a colloid mill. After sufficient preheating, the hot water is drained. The soap solution is added into a colloid mill to be sheared and stirred for about 30s, so that the shearing effect of the emulsifier and various auxiliary agents is ensured. Slowly adding asphalt base material which is constant at 140 ℃ and soap liquid together, and shearing and stirring in a colloid mill. In order to avoid the granular feeling of the asphalt, the emulsifying time is about 3 min.

(3) Opening the valve to flow out the prepared emulsified asphalt, sealing with a preservative film, and placing in a 60 ℃ oven for half an hour to defoam.

2. Preparing polymer microspheres: dissolving agar 2% in water based on 100% of the total mass of water, adding phosphate sodium salt 15%, stirring at normal temperature, and mixing to obtain the polymer microsphere emulsion.

3. And (2) uniformly mixing and stirring the emulsified asphalt and the polymer microsphere emulsion at the normal temperature according to the mass ratio of 1:0.6 to prepare the ultraviolet absorbent.

Example 2

(1) Heating the weighed water to 80 ℃, adding 0.4 percent of polyanionic cellulose (PAC) by taking the total mass of the asphalt substrate and the water as 100 percent, and continuously stirring to ensure that the polyanionic cellulose is firstly swelled and then dissolved. Adding non-ionic emulsifier lauroyl diethanol amine according to the amount, and stirring uniformly to obtain the soap solution.

3. Mixing: and (2) uniformly mixing and stirring the emulsified asphalt and the polymer microsphere emulsion at the normal temperature according to the mass ratio of 1:0.6 to prepare the ultraviolet absorbent.

Example 3

(2) Continuously circulating and preheating water with the temperature of about 70 ℃ in a colloid mill. After sufficient preheating, the hot water is drained. The soap solution is added into a colloid mill to be sheared and stirred for about 30s, so that the shearing effect of the emulsifier and various auxiliary agents is ensured. Slowly adding asphalt which is constant at 140 ℃ and soap solution together, and shearing and stirring in a colloid mill. In order to avoid the granular feeling of the asphalt, the emulsifying time is about 3 min.

2. Preparing polymer microspheres: dissolving agar 2% in water based on the total mass of water as 100%, adding phosphate sodium salt 10%, stirring at normal temperature, and mixing to obtain the polymer microsphere emulsion.

Example 4

1. Preparing emulsified asphalt: the dosage of the nonionic emulsifier lauroyl diethanol amine is 1.0 percent based on the total mass of the asphalt substrate and the water being 100 percent, wherein the mass ratio of the asphalt substrate to the water is 1:1.

(1) Heating weighed water to 80 deg.C, adding polyanionic cellulose (PAC) 0.8%, and stirring to make it swell first and then dissolve. Adding non-ionic emulsifier lauroyl diethanol amine according to the amount, and stirring uniformly to obtain the soap solution.

Example 5

3. And (2) uniformly mixing and stirring the emulsified asphalt and the polymer microsphere emulsion at the normal temperature according to the mass ratio of 1:0.2 to prepare the ultraviolet absorbent.

Example 6

3. And (2) uniformly mixing and stirring the emulsified asphalt and the polymer microsphere emulsion at the normal temperature according to the mass ratio of 1:0.8 to prepare the ultraviolet absorbent.

Comparative example 1

2. Preparing polymer microspheres: dissolving agar accounting for 2 percent of the total mass of water as 100 percent in water, mixing and stirring at normal temperature, and uniformly mixing to prepare the polymer microsphere emulsion.

Comparative example 2

(1) Heating the weighed water to 80 ℃, adding the nonionic emulsifier lauroyl diethanol amine according to the amount, and uniformly stirring to prepare the soap solution.

3. Mixing: and mixing the emulsified asphalt and the polymer microsphere emulsion according to the mass ratio of 1:0.6, stirring and mixing uniformly at normal temperature to prepare the ultraviolet absorbent.

Comparative example 3

2. Preparing an anti-ultraviolet aging solution: adding 15% of sodium phosphate by taking the total mass of water as 100%, mixing, stirring and uniformly mixing at normal temperature to prepare the sodium phosphate solution.

Comparative example 4

3. And (2) uniformly mixing and stirring the emulsified asphalt and the polymer microsphere emulsion at the normal temperature according to the mass ratio of 1:3 to prepare the ultraviolet absorbent.

Performance testing

The invention adopts zeta potential value to evaluate the stability of the ultraviolet-resistant emulsified asphalt stock solution and adopts an ultraviolet aging experiment to evaluate the ultraviolet aging resistance.

Zeta potential test: the numerical value of the zeta potential has good correlation with the stability of the emulsified asphalt, and the higher the zeta potential is, the more stable the system is; the lower the zeta potential, the more easily the particles in the emulsion agglomerate, break up in dispersion and break up the emulsion. The testing method is to immerse a detection sensor of the zeta potential instrument in the asphalt emulsion for detection.

Ultraviolet aging resistance test: and (3) carrying out a thermal oxidation ultraviolet aging accelerated test on the emulsified asphalt coating by using a fluorescent ultraviolet aging instrument. Respectively taking 50g +/-1 g of ultraviolet-resistant emulsified asphalt, pouring into a flat-bottom disc with the diameter of phi 140mm multiplied by 9.5mm, irradiating the sample by a 500W straight-tube ultraviolet high-pressure mercury lamp, controlling the distance between an ultraviolet lamp and the sample to be 45cm, controlling the internal temperature of an ultraviolet lamp box to be 85 ℃, respectively carrying out aging on the sample for 72 hours, and testing the performance change of the aged asphalt.

TABLE 1

As can be seen from Table 1, the softening points of the UV absorbers of examples 1-6 of the present invention after aging were all lowered to some extent, indicating that the UV absorbers of the present invention are excellent in resistance to UV aging and stability.

In comparative example 1, in which no anti-aging agent was added, the softening point increase after aging was too high, indicating that the product of comparative document 1 could not resist ultraviolet aging.

In comparative example 2, no stabilizer was added, in comparative example 3, no carrier was added, and the stability of both comparative example 2 and comparative example 3 was poor.

In comparative example 4, the mass ratio of the emulsified asphalt to the polymer microsphere emulsion is not within the range of the application, the emulsion breaking phenomenon occurs, and the ultraviolet absorbent product cannot be constructed.

It should be noted that, although the technical solutions of the present invention are described by specific examples, those skilled in the art can understand that the present invention should not be limited thereto.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen in order to best explain the principles of the embodiments, the practical application, or improvements made to the technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. An ultraviolet absorber, comprising the following composition:

an emulsified asphalt, said emulsified asphalt comprising a stabilizer, and

polymeric microspheres comprising a carrier and an anti-aging agent; wherein,

2. The ultraviolet absorbent according to claim 1, wherein the emulsified asphalt comprises an asphalt base, an emulsifier, a stabilizer and water, and preferably, the emulsifier is added in an amount of 0.1-5%, preferably 0.5-4%, based on 100% of the total mass of the asphalt base and the water; the addition amount of the stabilizer is 0.1-3%, preferably 0.5-3%.

3. The ultraviolet absorber according to claim 2, wherein the mass ratio of the asphalt base to the water is 0.5 to 2:1, preferably 0.7 to 1.5: 1.

4. The uv absorber according to claim 2 or 3, wherein the stabilizer comprises an organic stabilizer, preferably the organic stabilizer comprises a cellulose-based compound.

5. The ultraviolet absorber of any one of claims 2 to 4, wherein the emulsifier comprises a non-ionic emulsifier;

preferably, the non-ionic emulsifier comprises one or a combination of more than two of polyoxyethylene alkylolamide, alkylphenol polyoxyethylene, fatty alcohol polyoxyethylene, fatty amine polyoxyethylene, fatty acid polyoxyethylene, alkyl alcohol polyoxyethylene ether, block polyoxyethylene-polyoxypropylene ether and propylene glycol polyoxyethylene polyoxypropylene ether.

6. The ultraviolet absorber of any one of claims 1 to 5, wherein the polymeric microspheres comprise a carrier, an anti-aging agent, and water; preferably, the addition amount of the carrier is 0.5-5% by taking the total mass of water as 100%; the addition amount of the anti-aging agent is 5-20%.

7. The ultraviolet absorber as claimed in claim 6, wherein the mass ratio of the carrier to the aging inhibitor is 1:0.5 to 15.

8. The ultraviolet absorber according to claim 6 or 7, wherein the carrier comprises one or a combination of two or more of collagen, gelatin, agar; and/or

9. A method for preparing an ultraviolet absorber according to any one of claims 1 to 8, comprising the steps of:

a step of preparing emulsified asphalt;

preparing polymer microspheres;

and mixing the emulsified asphalt and the polymer microspheres.

10. A pavement maintenance coating comprising the ultraviolet absorber according to any one of claims 1 to 8.