WO2021077448A1

WO2021077448A1 - New and old pavement base course joining interface treatment material and preparation method therefor

Info

Publication number: WO2021077448A1
Application number: PCT/CN2019/113840
Authority: WO
Inventors: 张志祥; 金光来; 周文; 陈李峰; 关永胜; 刘海婷; 冯雯雯; 臧冬冬; 杜骋
Original assignee: 江苏中路工程技术研究院有限公司
Priority date: 2019-10-22
Filing date: 2019-10-29
Publication date: 2021-04-29
Also published as: CN110668754B; CN110668754A

Abstract

Disclosed are a new and old pavement base course joining interface treatment material and a preparation method therefor. The treatment material comprises, by weight, 50-100 parts of an organic silicon modified polyurethane emulsion, 1-3 parts of an organically modified rectorite, 100-200 parts of cement, 0.5-1.5 parts of a water-reducing agent, 20-50 parts of water and 0.5-2.5 parts of a composite retarder. The preparation method comprises the following steps: S1. preparing the organic silicon modified polyurethane emulsion, S2. preparing the organically modified rectorite, and S3. preparing the new and old pavement base course joining interface treatment material. The interface treatment material has a stable performance, a high bonding strength, and a good joining effect. The method has a simple preparation process.

Description

New and old pavement base layer splicing interface treatment material and preparation method thereof

Technical field

The invention relates to the field of road engineering, in particular to a treatment material for the splicing interface of new and old pavement base layers in highway reconstruction and expansion projects.

Background technique

In the highway reconstruction and expansion project, due to the long running time of the original pavement, the roadbed consolidation is relatively complete, while the expanded pavement belongs to the new pavement structure, and there is obvious settlement after construction, which will cause uneven settlement of the new and old pavement, resulting in damage to the road structure. Therefore, effective pavement splicing can avoid or delay the adverse effects on the expansion project due to settlement. Engineering experience shows that there are two key factors that affect the splicing effect of cement stabilized macadam bases: one is the bonding effect of the vertical interface between the new and old cement stabilized macadam bases; the second is the effect of laying cement stabilized macadam at the splicing site. Coarse aggregate dosage, segregation, etc. At present, there is still a lack of effective measures to ensure the splicing construction quality of cement stabilized crushed stone base, and there are no corresponding construction technical specifications and requirements.

Existing domestically completed highway reconstruction and expansion projects mostly adopt splicing technology of excavating steps and painting interface materials to improve the splicing effect of cement stabilized crushed stone base. Among them, the interface material is a key component in the splicing process of the new and old pavement base layer, and its performance and variety directly affect the quality and cost of the project. At present, the commonly used interface materials are mainly two-component waterborne polymer epoxy emulsion, cement paste, and emulsified asphalt.

The performance of the two-component waterborne polymer epoxy emulsion is unstable and is greatly affected by the mixing process. When the mixing is not strong during the preparation of the cement slurry, cement clusters will appear. The cement clusters will prevent the cement slurry from being fully combined when it is painted. The bonding of the base layer is prone to diseases such as hollowing and bubbling, which greatly reduces the bonding effect of the cement slurry; in addition, because the two-component material has a faster curing time, it usually solidifies within 1 to 2 hours to form strength. For reconstruction and expansion projects, the splicing interface treatment of the new and old base layer is usually before the new base layer is laid. After the two-component material is used for painting, the new base layer must be paved before the material is cured, that is, within 1 to 2 hours. Due to the complexity of the expansion project, the paving time of the base layer is affected by multiple factors such as mixture production, transportation, and paving equipment. The paving time is difficult to guarantee, resulting in the paving of the new base layer after the interface treatment material is solidified, which leads to the bonding of the old and new base layer The effect is poor, which affects the integrity of the expressway base after the widening.

The cement paste has a small bond strength to the concrete interface, which results in the unsatisfactory splicing effect of the cement stabilized crushed stone base of the new and old pavement; during the freezing and thawing process, the asphaltene of the emulsified asphalt will leak out, which affects the joints. The bonding condition and strength.

In view of this, the present invention provides a new and old pavement base layer splicing interface treatment material to solve the above-mentioned problems existing in the existing base layer splicing interface materials, and aims to provide a simple preparation process, stable performance, good flexibility, and high bonding strength , Good splicing effect of new and old pavement base layer splicing interface treatment materials.

Summary of the invention

The first object of the present invention is to provide a new and old pavement base layer splicing interface treatment material, which has stable performance, higher bonding strength, better water stability and fatigue cracking resistance, so as to ensure that the expressway is expanded The second purpose of the present invention is to provide a preparation method for the splicing interface treatment material of the new and old pavement base layer, the preparation method is simple, environmentally friendly, and has industrial value.

The above-mentioned technical purpose of the present invention is achieved through the following technical solutions:

A treatment material for the splicing interface of new and old pavement base layers. In parts by weight, it includes 50-100 parts of silicone modified polyurethane emulsion, 1-3 parts of organically modified rectorite, 100-200 parts of cement, and 0.5-parts of water reducing agent. 1.5 parts, 20-50 parts of water and 0.5-2.5 parts of composite retarder. Organic modification of rectorite with organic modifier can improve the compatibility between rectorite and polyurethane; at the same time, the molecular chain of organic modifier is arranged in a certain way between rectorite flakes to expand The crystal plane spacing of rectorite is conducive to the intercalation/peeling reaction between polyurethane and rectorite. The molecular chain of polyurethane is inserted into the rectorite layer, which can comprehensively complement the excellent properties of polyurethane and rectorite and improve the material. The bonding performance, heat resistance, corrosion resistance and mechanical properties of the product.

Further, the cement is a mixture of any one or more of ordinary Portland cement, slag Portland cement or fly ash Portland cement.

Further, the water reducing agent is any one or a mixture of polycarboxylic acid water reducing agent or sulfonated acetone formaldehyde condensate. The addition of polycarboxylic acid superplasticizer can improve the workability of the splicing interface treatment material, and at the same time can reduce the shrinkage of the splicing interface treatment material.

Further, the composite retarder is a combination of an organic retarder and an inorganic retarder, wherein the organic retarder is any one of calcium sugar, glucose or citric acid, and the inorganic retarder is phosphate, borax or Any one of calcium fluorosilicate. The use of composite retarder is a compound of organic and inorganic retarders, which effectively delays the setting time. Organic retarder, with strong solid-liquid surface activity, can be adsorbed on the surface of polyurethane emulsion to form a solvent adsorption layer, which prevents latex particles from contacting and cohesive demulsification, thereby effectively delaying the demulsification and solidification of polyurethane emulsion; inorganic retarder is electrolyte Salts can ionize in the aqueous solution to bring out sodium ions, calcium ions, etc., delay the formation of cement hydration products calcium hydroxide and ettringite, thereby prolonging the initial setting time of cement. The use of a composite retarder can greatly extend the demulsification time of polyurethane emulsion and the initial setting time of cement, and allow sufficient time for the new base paving to ensure that the new base pavement is cured after the interface material is cured, so that the old and new bases can be bonded to form a whole. Conducive to the durability of the base after the expansion.

Furthermore, the polyurethane emulsion, in parts by weight, includes the following components: 90-100 parts of polyether polyol, 0-10 parts of silicone, 70-100 parts of polyisocyanate, 5-15 parts of hydrophilic chain extender, 3-7 parts of salt-forming agent, 300-500 parts of water, 0.05-0.1 parts of polyurethane emulsion defoamer.

Further, the polyether polyol is a polyether polyol with an average functionality of not less than 3 and an average molecular weight of about 8000. It can be polytetrahydrofuran ether glycol, tetrahydrofuran-oxypropylene ether copolymer glycol or polyoxypropylene ether two. Any one or a mixture of two kinds of alcohols.

Further, the organosilicon is polysiloxane, which is any one or a mixture of polymethylsiloxane, two-tailed dihydroxysiloxane, and two-terminal hydroxybutyl polydimethylsiloxane.

Further, the isocyanate is selected from any one of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polyphenyl polymethylene polyisocyanate (PAPI) or MDI/TDI system isocyanate.

Further, the hydrophilic chain extender is any one or a mixture of sodium 1,4-butanediol-2-sulfonate or dimethylolpropionic acid. Add a hydrophilic chain extender to the synthetic silicone-modified polyurethane prepolymer, and introduce hydrophilic groups on the silicone-modified polyurethane prepolymer to achieve uniform dispersion of the silicone-modified polyurethane in water. The process of organosilicon modified polyurethane emulsion does not need to introduce high boiling point solvents, which is green and environmentally friendly.

Further, the salt-forming agent is selected from any one of triethylamine, dimethylethanolamine or sodium hydroxide.

Furthermore, the polyurethane emulsion defoamer is composed of mineral oil, special polyether ester and dispersant. The addition of defoamer in the silicone-modified polyurethane emulsion can not only quickly eliminate the bubbles generated during the preparation of the silicone-modified polyurethane emulsion, but also rupture the bubbles adsorbed at the concrete interface, which improves the density of the interface transition zone. And the role of bond strength.

Furthermore, the organically modified rectorite includes 25-35 parts by weight of rectorite, 10-15 parts of organic modifier, and 500-700 parts of purified water. The cement is added to the organic rectorite modified polyurethane emulsion. On the one hand, the water in the silicone modified polyurethane emulsion (without additional water) is used to realize the hydration of the cement, and the cement is formed with rectorite and polyurethane after hydration Network interpenetrating multi-element composite structure; on the other hand, the -NCO group in the silicone-modified polyurethane emulsion _{reacts with the Ca(OH) 2} enriched in the base concrete interface to generate stable urethane and reduce the interface The degree of Ca(OH) ₂ enrichment, the generated carbamate can also fill the pores at the concrete interface, thereby further improving the compactness and bonding strength of the interface transition zone.

Further, rectorite is one or a mixture of sodium-based rectorite, calcium-based rectorite, or magnesium-based rectorite.

Further, the organic modifier is selected from the group consisting of octadecyl dimethyl benzyl ammonium chloride, cetyl trimethyl ammonium chloride, cetyl trimethyl ammonium bromide, and octadecyl trimethyl ammonium chloride. Any one or a mixture of any two of ammonium chloride or γ-propyltrimethoxysilane.

Further, the preparation method of the treatment material for the splicing interface of the new and old pavement base layer includes the following steps:

S1. Preparation of silicone modified polyurethane emulsion: place 90-100 parts of polyether polyol, 0-10 parts of silicone, 70-100 parts of polyisocyanate, and 5-15 parts of hydrophilic chain extender at a temperature of 70 In a reactor at ℃～90℃, react for 4～5h under nitrogen protection to obtain silicone modified polyurethane prepolymer; mix 3～7 parts of salt-forming agent, 300～500 parts of water, 0.05～0.1 parts of water The special defoamer for polyurethane emulsion is added to the aforementioned silicone-modified polyurethane prepolymer to mix and react to obtain a silicone-modified polyurethane emulsion;

S2. Preparation of organically modified rectorite: add 25-35 parts of rectorite with a cation exchange capacity of 90mmol/100g into 500-700 parts of purified water, stir at 75℃～85℃ for 20～25min, make it accumulate The tropite is evenly dispersed to obtain a homogeneous system of rectorite and water; add 10-15 parts of organic modifier to 50-15 parts of purified water, stir evenly, and then add to the above-mentioned homogeneous system of rectorite and water , Stir at 75℃～85℃ for 2～4h to obtain the organic modified rectorite emulsion; use a vacuum pump to suction and filter the above organic modified rectorite emulsion to obtain a filter cake, which is washed with pure water, repeat 4-6 times, then the filter cake is fully dried in a vacuum drying oven at 80-100°C, ground into powder, and passed through a 200-300 mesh sieve to obtain organically modified rectorite;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: slowly add 1 to 3 parts of organically modified rectorite to 50-100 parts of silicone polyurethane emulsion, and stir for 15 to 20 minutes to obtain organic rectorite modified Silicone polyurethane emulsion; then mix and stir the prepared organic rectorite modified silicone polyurethane emulsion, 20-50 parts of water, 0.5-1.5 parts of water reducing agent and 0.5-2.5 parts of composite retarder. Finally, add 100 to 200 parts of cement and continue to mix for 2 to 5 minutes to obtain the interface treatment material for the splicing of new and old pavement levels.

In summary, the present invention has the following beneficial effects:

1. The composite retarder used in the present invention has a wide range of raw materials, low price, and excellent retardation effect. The dosage of the composite retarder can be adjusted according to the needs of on-site construction to meet the requirements of the time required for construction.

2. The present invention uses ultra-high molecular weight polyether polyol to prepare polyurethane modifier, which can improve the brittleness of traditional polyurethane, thereby improving the adhesion flexibility and deformation coordination of the new and old pavement base layer splicing interface treatment materials, which is beneficial to the new and old in the expansion project. The anti-cracking performance of the pavement base layer splicing part.

3. The present invention uses organic silicon and organic rectorite composite modified polyurethane, which has the following advantages: 1) Silicone has many excellent properties such as weathering resistance, ozone resistance, high and low temperature resistance, and good bonding performance. It uses organic Silicon-modified polyurethane can combine the excellent properties of the two to improve the cohesiveness, high and low temperature resistance and durability of the interface treatment material of the splicing interface of the new and old pavement base. 2) The organic rectorite, the hydration product of the cement hydration and the polyurethane form a network interpenetrating multi-element composite structure, which is beneficial to improve the compactness and bonding strength of the splicing interface of the new and old pavement base layer. It can be seen from the general that the composite modification of organic silicon and organic rectorite makes the prepared polyurethane modifier have excellent bonding performance, durability and high and low temperature resistance, so that the prepared splicing interface treatment material has better comprehensive performance , Which is beneficial to the bonding of the new and old bases in the expansion project and the durability of the splicing joints of the new and old bases and prolongs the service life of the road.

4. Compared with the epoxy latex interface agent, the splicing interface treatment material of the new and old pavement base layer prepared by the present invention has better bonding performance, longer curing and initial setting time, and stable performance; the splicing interface treatment material coating prepared by the present invention After brushing at the splicing interface, a polymer slurry with good bonding performance can be formed. The slurry film formation is continuous without obvious bubbles, and it is not easy to fall off and bulge. After comparison tests, the splitting strength of cement stabilized crushed stone specimens is significantly improved after using the splicing interface treatment material prepared by the present invention.

5. The preparation process of the present invention is simple, reaction conditions are easy to control, raw materials are cheap, and suitable for industrial development; no solvent is required, no pollution to the environment, and environmental protection.

Detailed ways

In order to make the above and other objectives, features, and advantages of the present invention more obvious and understandable, preferred embodiments are listed below.

Example 1: A treatment material for the splicing interface of new and old pavement base layers and its preparation method

A treatment material for the splicing interface of new and old pavement base layers, calculated in parts by weight, including the following components:

50 parts of silicone modified polyurethane emulsion, 1 part of organically modified rectorite, 100 parts of ordinary Portland cement, 0.5 parts of polycarboxylic acid water reducer, 0.2 parts of sugar calcium and 0.3 parts of phosphate.

Polyurethane emulsion, in parts by weight, includes the following components:

95 parts of polytetrahydrofuran ether glycol, 5 parts of silicone, 70 parts of diphenylmethane diisocyanate, 5 parts of sodium 1,4-butanediol-2-sulfonate, 3 parts of triethylamine, 300 parts of water, polyurethane 0.05 parts of emulsion defoamer.

Organically modified rectorite, in parts by weight, includes the following components:

25 parts of sodium rectorite, 10 parts of octadecyl dimethyl benzyl ammonium chloride and 500 parts of water.

A preparation method of treatment material for splicing interface between new and old pavement base layers:

S1. Preparation of silicone modified polyurethane emulsion: Place 95 parts of polyether polyol, 5 parts of silicone, 70 parts of diphenylmethane diisocyanate and 5 parts of sodium 1,4-butanediol-2-sulfonate In a reactor set at 70℃, react for 5 hours under nitrogen protection to obtain silicone modified polyurethane prepolymer; add 3 parts of triethylamine, 300 parts of water and 0.05 parts of polyurethane emulsion defoamer to the above The polyorganosilicon-modified urethane prepolymer is mixed and reacted to obtain a silicone-modified polyurethane emulsion;

S2. Preparation of organically modified rectorite: add 25 parts of sodium-based rectorite with a cation exchange capacity of 90mmol/100g to 500 parts of purified water, and stir at 75°C for 20 minutes to make the sodium-based rectorite evenly dispersed. Obtain a homogeneous system of sodium rectorite and water; add 10 parts of octadecyl dimethyl benzyl ammonium chloride to 5 parts of purified water, stir evenly, and then add to the above homogeneous system of rectorite and water , Stir at 75°C for 2h to obtain an organic modified rectorite emulsion; suction and filter the above organic modified rectorite emulsion with a vacuum pump to obtain a filter cake, which is washed with purified water, repeated 4-6 times, Then the filter cake is fully dried in a vacuum drying oven at 80°C, ground into powder, and passed through a 200-300 mesh sieve to obtain organically modified rectorite;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: slowly add 1 part of organically modified rectorite to 50 parts of silicone modified polyurethane emulsion, and stir for 15 minutes to obtain organic rectorite modified silicone polyurethane emulsion ; Then add 20 parts of water, 0.5 parts of polycarboxylic acid water reducing agent, 0.2 parts of sugar calcium and 0.3 parts of phosphate into the above organic rectorite modified polyurethane emulsion, stir for 1 min, and finally add 100 parts of ordinary silicate The cement can be mixed for 3 minutes to obtain the treatment material for the splicing interface of the new and old roads.

Example 2: A treatment material for the splicing interface of new and old pavement base layers and its preparation method

A treatment material for the splicing interface of new and old pavement base layers, in parts by weight, including: 100 parts of silicone modified polyurethane emulsion, 3 parts of organically modified rectorite, 200 parts of slag Portland cement, and sulfonated acetone-formaldehyde condensate 1.5 parts, 1 part glucose and 0.5 parts borax.

The silicone modified polyurethane emulsion, in parts by weight, includes the following components: 92 parts of tetrahydrofuran-propylene oxide ether copolymer glycol, 8 parts of silicone, 100 parts of polyphenyl polymethylene polyisocyanate, dimethylol 15 parts of propionic acid, 7 parts of dimethylethanolamine, 500 parts of water, 0.1 part of polyurethane emulsion defoamer.

35 parts of calcium rectorite, 15 parts of cetyltrimethylbenzyl ammonium chloride and 700 parts of water.

The preparation method of the treatment material for the splicing interface of the new and old pavement base layer includes the following steps:

S1. Preparation of silicone modified polyurethane emulsion: Place 92 parts of tetrahydrofuran-propylene oxide ether copolymer diol, 8 parts of silicone, 100 parts of polyphenylpolymethylene polyisocyanate and 15 parts of dimethylolpropionic acid In a reactor set at 90℃, react for 5 hours under nitrogen protection to obtain a silicone modified polyurethane prepolymer; add 7 parts of dimethylethanolamine, 500 parts of water and 0.1 parts of polyurethane emulsion defoamer to Mixing reaction in the aforementioned silicone-modified polyurethane prepolymer to obtain a silicone-modified polyurethane emulsion;

S2. Preparation of organically modified rectorite: add 35 parts of calcium-based rectorite with a cation exchange capacity of 90mmol/100g to 650 parts of purified water, and stir at 85°C for 25 minutes to make the calcium-based rectorite evenly dispersed. Obtain a homogeneous system of calcium-based rectorite and water; add 5 parts of cetyltrimethylammonium chloride to 15 parts of purified water, stir evenly, and then add to the above-mentioned homogeneous system of rectorite and water, Stir at 85°C for 4 hours to obtain an organic modified rectorite emulsion; suction and filter the above organic modified rectorite emulsion with a vacuum pump to obtain a filter cake, which is washed with purified water, repeated 4-6 times, and then Place the filter cake in a vacuum drying oven at 80-100°C to fully dry it, grind it into powder, and pass through a 200-300 mesh sieve to obtain organically modified rectorite;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: slowly add 3 parts of organically modified rectorite to 100 parts of silicone modified polyurethane emulsion and stir for 20 minutes to obtain organic rectorite modified silicone polyurethane emulsion ; Then add 50 parts of water, 1.5 parts of sulfonated acetone formaldehyde condensate, 1.5 parts of glucose and 1 part of borax to the above organic rectorite modified polyurethane emulsion, stir for 1 min, and finally add 200 parts of slag cement and continue to stir for 4 min. The splicing interface treatment materials of new and old pavement layers can be obtained.

Example 3. A treatment material for the splicing interface of new and old pavement base layers, in parts by weight, including 75 parts of silicone modified polyurethane emulsion, 2 parts of organically modified rectorite, 150 parts of fly ash Portland cement, and less 1 part of liquid, 1 part of citric acid and 1 part of calcium fluosilicate.

The silicone modified polyurethane emulsion, in parts by weight, includes the following components: 90 parts of polyoxypropylene ether glycol, 10 parts of silicone, 90 parts of toluene diisocyanate, 1,4-butanediol-2 sulfonic acid 4 parts of sodium, 5 parts of dimethylolpropionic acid, 7 parts of sodium hydroxide, 400 parts of water and 0.075 parts of polyurethane emulsion defoamer.

30 parts of magnesium-based rectorite, 15 parts of cetyltrimethyl bromide and 400 parts of water.

S1. Preparation of silicone modified polyurethane emulsion: 90 parts of polyoxypropylene ether glycol, 10 parts of silicone, 90 parts of toluene diisocyanate, 4 parts of sodium 1,4-butanediol-2 sulfonate and dimethylol Place 5 parts of propyl propionic acid in a reactor set at 80℃, and react for 5 hours under nitrogen protection to obtain silicone modified polyurethane prepolymer; combine 7 parts of sodium hydroxide, 400 parts of water and polyurethane emulsion defoamer 0.075 parts are added to the aforementioned silicone-modified polyurethane prepolymer for mixing and reaction to obtain a silicone-modified polyurethane emulsion;

S2. Preparation of organically modified rectorite: Add 30 parts of magnesium-based rectorite with a cation exchange capacity of 90mmol/100g to 700 parts of purified water, and stir at 80°C for 22 minutes to make the magnesium-based rectorite evenly dispersed. Obtain a homogeneous system of magnesium-based rectorite and water; add 15 parts of cetyltrimethyl bromide to 15 parts of purified water, stir evenly, and then add to the above-mentioned homogeneous system of rectorite and water. Stir at ℃ for 3 hours to obtain an organic modified rectorite emulsion; use a vacuum pump to suction and filter the above organic modified rectorite emulsion to obtain a filter cake. The filter cake is washed with purified water and repeated 4-6 times. The cake is fully dried in a vacuum drying oven at 90°C, ground into powder, and passed through a 200-300 mesh sieve to obtain organically modified rectorite;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: slowly add 2 parts of organically modified rectorite to 75 parts of silicone modified polyurethane emulsion and stir for 15-20 minutes to obtain organic rectorite modified silicone Polyurethane emulsion; then add 40 parts of water, 1 part of polycarboxylic acid water reducing agent, 1 part of citric acid and 1 part of calcium fluorosilicate into the above organic rectorite modified polyurethane emulsion, stir for 1.5min, and finally add 150 parts of pulverized coal The gray Portland cement continues to mix for 4 minutes to obtain the treatment material for the splicing interface of the new and old pavement layers.

Example 4. A treatment material for the splicing interface of new and old pavement base layers and its preparation method

50 parts of silicone modified polyurethane emulsion, 1 part of organically modified rectorite, 100 parts of ordinary Portland cement, 0.5 parts of polyhydroxy acid water reducing agent, 0.2 parts of sugar calcium and 0.3 parts of phosphate.

The silicone modified polyurethane emulsion, in parts by weight, includes the following components:

98 parts of polytetrahydrofuran ether glycol, 2 parts of silicone, 70 parts of a mixture of toluene diisocyanate and diphenylmethane diisocyanate, 5 parts of sodium 1,4-butanediol-2-sulfonate, 3 parts of triethylamine, 300 parts of water, 0.05 parts of polyurethane emulsion defoamer.

25 parts of sodium rectorite, 10 parts of octadecyl trimethyl ammonium chloride and 500 parts of water.

S1. Preparation of silicone modified polyurethane emulsion: 98 parts of polyether polyol, 2 parts of silicone, 70 parts of toluene diisocyanate and diphenylmethane diisocyanate mixture and 5 parts of 1,4-butanediol-2- Sodium sulfonate is placed in a reaction kettle with a temperature of 70°C to 90°C, and reacted for 4 to 5 hours under nitrogen protection to obtain a silicone modified polyurethane prepolymer; 3 parts of triethylamine, 300 parts of water and 0.05 Part of the polyurethane emulsion defoamer is added to the above-mentioned silicone-modified polyurethane prepolymer for mixing and reaction to obtain a silicone-modified polyurethane emulsion;

S2. Preparation of organically modified rectorite: add 25 parts of sodium-based rectorite with a cation exchange capacity of 90mmol/100g to 450 parts of purified water, and stir at 75°C for 20 minutes to make the sodium-based rectorite evenly dispersed. Obtain a homogeneous system of sodium rectorite and water; add 10 parts of octadecyl trimethyl ammonium chloride to 5 parts of purified water, stir evenly, and then add to the above homogeneous system of rectorite and water. Stir at 75°C for 2 hours to obtain an organic modified rectorite emulsion; use a vacuum pump to suction and filter the above organic modified rectorite emulsion to obtain a filter cake. The filter cake is washed with purified water and repeated 4 to 6 times. The filter cake is fully dried in a vacuum drying oven at 80°C, ground into powder, and passed through a 200-300 mesh sieve to obtain organically modified rectorite;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: slowly add 1 part of organically modified rectorite to 50 parts of silicone modified polyurethane emulsion, and stir for 15 minutes to obtain organic rectorite modified silicone polyurethane emulsion ; Then 100 parts of ordinary Portland cement, 0.5 parts of polycarboxylic acid water reducing agent, 0.2 parts of sugar calcium and 0.3 parts of phosphate are added to the above organic rectorite modified polyurethane emulsion, and stirred at room temperature for 3 minutes to obtain new and old roads The splicing interface treatment material.

Example 5. A treatment material for the splicing interface of new and old pavement base layers and its preparation method

A treatment material for the splicing interface of new and old pavement base layers, in parts by weight, including: 100 parts of silicone modified polyurethane emulsion, 3 parts of organically modified rectorite, 200 parts of slag Portland cement, and sulfonated acetone-formaldehyde condensate 1.5 parts, 1 part dextrose and 0.5 parts borax.

The silicone modified polyurethane emulsion, in parts by weight, includes the following components: 94 parts of tetrahydrofuran-propylene oxide ether copolymer diol, 6 parts of silicone, 100 parts of polyphenylpolymethylene polyisocyanate, dimethylol 15 parts of propionic acid, 7 parts of dimethylethanolamine, 500 parts of water, 0.1 part of polyurethane emulsion defoamer.

35 parts of calcium-based rectorite, 15 parts of γ-propyltrimethoxysilane, 700 parts of water.

S1. Preparation of silicone modified polyurethane emulsion: 94 parts of tetrahydrofuran-propylene oxide ether copolymer diol, 6 parts of silicone, 100 parts of polyphenylpolymethylene polyisocyanate, 15 parts of dimethylolpropionic acid are placed In a reactor set at 90℃, react for 5 hours under nitrogen protection to obtain silicone modified polyurethane prepolymer; add 7 parts of dimethylethanolamine, 500 parts of water and 0.1 parts of polyurethane emulsion special defoamer Mixing and reacting in the aforementioned silicone-modified polyurethane prepolymer to obtain a silicone-modified polyurethane emulsion;

S2. Preparation of organically modified rectorite: add 35 parts of calcium-based rectorite with a cation exchange capacity of 90mmol/100g to 650 parts of purified water, and stir at 85°C for 25 minutes to make the calcium-based rectorite evenly dispersed. Obtain a homogeneous system of calcium-based rectorite and water; add 5 parts of γ-propyltrimethoxysilane to 15 parts of purified water, stir evenly, and then add to the above-mentioned homogeneous system of rectorite and water. Stir for 4 hours at ℃ to obtain an organic modified rectorite emulsion; use a vacuum pump to suction and filter the above organic modified rectorite emulsion to obtain a filter cake. The filter cake is washed with purified water and repeated 4 to 6 times. The cake is fully dried in a vacuum drying oven at 80-100°C, ground into powder, and passed through a 200-300 mesh sieve to obtain organically modified rectorite;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: slowly add 3 parts of organically modified rectorite to 100 parts of silicone modified polyurethane emulsion and stir for 20 minutes to obtain organic rectorite modified silicone polyurethane emulsion ; Then 200 parts of slag Portland cement, 1.5 parts of sulfonated acetone formaldehyde condensate, 1.5 parts of glucose and 1 part of borax are added to the above organic rectorite modified polyurethane emulsion, and stirred at room temperature for 3 to 5 minutes to get the new and old pavement levels The splicing interface treatment material.

Example 6. A treatment material for the splicing interface of new and old pavement base courses, in parts by weight, including 75 parts of silicone modified polyurethane emulsion, 2 parts of organically modified rectorite, 150 parts of fly ash Portland cement, and less 1 part of liquid, 1 part of citric acid and 1 part of calcium fluosilicate.

The silicone modified polyurethane emulsion, in parts by weight, includes the following components: 97 parts of polyoxypropylene ether glycol, 3 parts of silicone, 90 parts of diphenylmethane diisocyanate, 1,4-butanediol- 2 4 parts of sodium sulfonate, 5 parts of dimethylolpropionic acid, 7 parts of sodium hydroxide, 400 parts of water and 0.075 parts of polyurethane emulsion defoamer.

S1. Preparation of silicone modified polyurethane emulsion: 97 parts of polyoxypropylene ether glycol, 3 parts of silicone, 90 parts of diphenylmethane diisocyanate, 4 parts of 1,4-butanediol-2 sodium sulfonate, Place 5 parts of dimethylolpropionic acid in a reactor set at 80℃, and react for 5 hours under nitrogen protection to obtain silicone modified polyurethane prepolymer; combine 7 parts of sodium hydroxide, 400 parts of water, and polyurethane emulsion 0.075 parts of defoamer is added to the above-mentioned silicone-modified polyurethane prepolymer for mixing and reaction to obtain a silicone-modified polyurethane emulsion;

S2. Preparation of organically modified rectorite: Add 39 parts of magnesium-based rectorite with a cation exchange capacity of 90mmol/100g to 700 parts of purified water, and stir at 80°C for 22 minutes to make the magnesium-based rectorite evenly dispersed. Obtain a homogeneous system of magnesium-based rectorite and water; add 15 parts of cetyltrimethyl bromide to 15 parts of purified water, stir evenly, and then add to the above-mentioned homogeneous system of rectorite and water. Stir at ℃ for 3 hours to obtain an organic modified rectorite emulsion; use a vacuum pump to suction and filter the above organic modified rectorite emulsion to obtain a filter cake. The filter cake is washed with purified water and repeated 4-6 times. The cake is fully dried in a vacuum drying oven at 90°C, ground into powder, and passed through a 200-300 mesh sieve to obtain organically modified rectorite;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: slowly add 2 parts of organically modified rectorite to 75 parts of silicone modified polyurethane emulsion and stir for 15-20 minutes to obtain organic rectorite modified silicone Polyurethane emulsion; then add 35 parts of water, 1 part of polycarboxylic acid water reducing agent, 1 part of citric acid and 1 part of calcium fluorosilicate into the above organic rectorite modified polyurethane emulsion, stir for 1 minute, and finally add 150 parts of fly ash Portland cement continues to mix for 5 minutes to obtain the treatment material for the splicing interface of the new and old pavement layers.

Example 7. A treatment material for the splicing interface of new and old pavement base layers and its preparation method

A treatment material for the splicing interface of new and old pavement base layers, in parts by weight, including: 100 parts of silicone modified polyurethane emulsion, 3 parts of organically modified rectorite, 200 parts of slag Portland cement, and sulfonated acetone-formaldehyde condensate 1.5 parts, 1 part glucose, 0.5 parts borax.

Silicone modified polyurethane emulsion, calculated according to mass fraction, includes the following components: 96 parts of tetrahydrofuran-propylene oxide ether copolymer diol, 4 parts of silicone, 100 parts of toluene diisocyanate, 15 parts of dimethylolpropionic acid, two 7 parts of methylethanolamine, 500 parts of water, 0.1 part of polyurethane emulsion defoamer.

35 parts of calcium rectorite, 15 parts of cetyltrimethylbenzyl ammonium chloride, 700 parts of water.

S1. Preparation of silicone modified polyurethane emulsion: 96 parts of tetrahydrofuran-propylene oxide ether copolymer diol, 4 parts of silicone, 100 parts of toluene diisocyanate, 15 parts of dimethylolpropionic acid are placed at a temperature of 90°C In the reactor, react for 5 hours under the protection of nitrogen to obtain silicone modified polyurethane prepolymer; add 7 parts of dimethylethanolamine, 500 parts of water, and 0.1 part of polyurethane emulsion special defoamer to the above polyurethane prepolymer Medium mixing reaction to obtain silicone modified polyurethane emulsion;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: slowly add 3 parts of organically modified rectorite to 100 parts of silicone modified polyurethane emulsion and stir for 20 minutes to obtain organic rectorite modified silicone polyurethane emulsion ; Then 45 parts of water, 1.5 parts of sulfonated acetone formaldehyde condensate, 1.5 parts of glucose and 1 part of borax were added to the above organic rectorite modified polyurethane emulsion and stirred for 1 min, and finally 200 parts of slag Portland cement were added and stirred for 4 min. The splicing interface treatment materials of the new and old pavement base can be obtained.

The above-mentioned new and old pavement base layer splicing interface treatment materials and epoxy latex cement slurry interface agent are jointly tested for setting time, bonding performance (adhesive pull-out strength, composite pull-out strength), durability (freeze-thaw cycle compressive strength loss Rate, freeze-thaw cycle quality loss rate). The above-mentioned new and old pavement base layer splicing interface treatment materials and epoxy latex cement slurry interface agent were prepared according to the mortar ratio of 1:2 to prepare cement mortar, 28d compressive and flexural strengths were measured, and the mechanical properties of the two materials were evaluated. The results are as follows:

Various performance test results

According to the performance test results, the treatment material provided by the present invention has a longer setting time than the epoxy latex cement interface agent, meets the construction requirements of the expansion project, and is more excellent in bonding performance and durability. The mechanical properties are especially flexural. It has better strength and industrial value.

This specific embodiment is only an explanation of the present invention, and is not a limitation of the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contribution as needed, but as long as the rights of the present invention The scope of the requirements is protected by the patent law.

Claims

A material for treating the splicing interface of new and old pavement base layers, which is characterized in that, in parts by weight, it comprises 50-100 parts of organic silicon modified polyurethane emulsion, 1-3 parts of organically modified rectorite, and 100-200 parts of cement. 0.5 to 1.5 parts of water, 20 to 50 parts of water and 0.5 to 2.5 parts of composite retarder.
The interface treatment material for splicing new and old pavement base layers according to claim 1, wherein the silicone modified polyurethane emulsion, in parts by weight, comprises the following components: 90-100 parts of polyether polyol, 0-10 parts of organic silicon, 70-100 parts of isocyanate, 5-15 parts of hydrophilic chain extender, 3-7 parts of salt-forming agent, 300-500 parts of water, 0.05-0.1 parts of polyurethane emulsion defoamer.
The splicing interface treatment material for new and old pavement base layers according to claim 2, wherein the polyether polyol is an ultra-high molecular weight polyether polyol with a molecular weight of about 8000, so that the polyurethane emulsion has better flexibility .
The interface treatment material for the splicing of new and old pavement base layers according to claim 2, wherein the silicone is polysiloxane, and the polysiloxane is polymethylsiloxane, two-tailed dihydroxy silicone Any one or a mixture of alkane and two-terminal hydroxybutyl polydimethylsiloxane.
The new and old pavement base layer splicing interface treatment material according to claim 2, wherein the isocyanate is xylene methane diisocyanate or any one or a mixture of polymethylene polyphenyl polyisocyanate.
The splicing interface treatment material for new and old pavement base layers according to claim 2, wherein the hydrophilic chain extender is sodium 1,4-butanediol-2-sulfonate or dimethylolpropionic acid. Any one or a mixture of two.
The new and old pavement base layer splicing interface treatment material according to claim 1, wherein the organically modified rectorite includes 25 to 35 parts of rectorite and 10 to 15 parts by weight of the organic modifier. Servings, 500-700 servings of purified water.
The new and old pavement base layer splicing interface treatment material according to claim 7, wherein the rectorite is one or more of sodium-based rectorite, calcium-based rectorite, or magnesium-based rectorite mixture.
The interface treatment material for splicing new and old pavement base courses according to claim 7, wherein the organic modifier is selected from the group consisting of octadecyl dimethyl benzyl ammonium chloride and cetyl trimethyl ammonium chloride , Cetyltrimethylammonium bromide, octadecyltrimethylammonium chloride or γ-propyltrimethoxysilane or a mixture of any two.
The preparation method of the treatment material for the splicing interface of the new and old pavement base layer is characterized in that it comprises the following steps:

S1. Preparation of silicone-modified polyurethane emulsion: first put polyether polyol, silicone, polyisocyanate, coupling agent, and hydrophilic chain extender in a reactor, and react under the protection of nitrogen to obtain silicone-modified polyurethane emulsion. Polymer; adding a salt-forming agent, water and a special defoamer for polyurethane emulsion to the polyurethane prepolymer and mixing reaction to obtain a silicone modified polyurethane emulsion;

S2. Preparation of organically modified rectorite: add rectorite with a cation exchange capacity of 90mmol/100g into water, stir to disperse rectorite evenly, and obtain a homogeneous system of rectorite and water; add organic modifier to water, Stir evenly, then add it to the homogeneous system of rectorite and water, and stir to obtain the organic modified rectorite emulsion; the organic modified rectorite emulsion is suction filtered to obtain a filter cake, the filter cake is washed with water, and then filtered The cake is dried, ground into powder, and passed through a 200-300 mesh sieve to obtain organically modified rectorite;

S3. Preparation of new and old pavement base layer splicing interface treatment materials: adding organically modified rectorite to the silicone modified polyurethane emulsion, stirring to obtain the organic rectorite modified silicone polyurethane emulsion; then the organic rectorite modified organic The silicone polyurethane emulsion, water, water reducing agent and composite retarder are mixed and stirred uniformly, and finally cement is added and the stirring is continued to obtain the splicing interface treatment material of the new and old pavement base layer.