CN112552761A

CN112552761A - Concrete salt-resistant protective agent

Info

Publication number: CN112552761A
Application number: CN202011500601.0A
Authority: CN
Inventors: 杨华
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-12-18
Filing date: 2020-12-18
Publication date: 2021-03-26

Abstract

The application relates to the field of concrete protection, and particularly discloses a concrete salt-resistant protective agent. A concrete salt-resistant protective agent comprises a component A and a component B, wherein the component A comprises 1-10 parts of alkyl siloxane, 10-20 parts of sodium alginate, 3-4 parts of calcium gluconate and 2.1-2.9 parts of a dispersing agent, the component A is coated to prepare microcapsule particles with the average particle size of 50nm, and the component B comprises 0.01-0.1 part of silicone-acrylate emulsion; the component A and the component B are stored separately, and are added into distilled water to be blended when in use, so as to be compounded into the concrete salt-resistant protective agent. The microcapsule A can quickly permeate into concrete along with water and slowly release in the concrete, so that the time for forming an organic silicon network by condensing the silicon hydroxyl of the alkyl siloxane and the hydroxyl existing in the concrete is prolonged, the permeability of the concrete salt-resistant protective agent is increased, and a hydrophobic membrane formed by the concrete salt-resistant protective agent is deeper due to larger penetration depth of the concrete salt-resistant protective agent, so that better waterproof salt resistance is achieved.

Description

Concrete salt-resistant protective agent

Technical Field

The application relates to the field of concrete protection, in particular to a concrete salt-resistant protective agent.

Background

The concrete is a composite material consisting of cement, aggregate and water, and is provided with pores. The pores of the concrete provide passages for the invasion of external chloride ion salts, and the chloride ion salts can permeate into the concrete along with water through modes of capillary action, osmosis action, diffusion action and the like and react with cement hydration products to cause the phenomena of expansion, cracking, peeling and the like of the concrete, so that the strength and the cohesiveness of the concrete are reduced or even lost. Therefore, concrete needs to be protected from the corrosion of chloride ion salts.

Common concrete salt-resistant protective agents comprise a penetration protective agent and a film-forming protective agent, wherein the penetration protective agent reacts with cement hydration products in concrete on the surface of concrete pores to form a hydrophobic film, so that the contact angle between the concrete pores and water is changed, and the waterproof and salt-resistant effects are achieved. Meanwhile, the permeable protective agent can penetrate into the concrete, is less in physical and chemical damage and has better protection and durability compared with a film-forming protective agent.

The traditional penetration protective agent mainly uses cement-based penetration crystalline coating to develop fluorine and silicon penetration protective agents, but because the fluorine penetration protective agent has higher cost, the silicon penetration protective agent mainly using organic silicon solution is more widely used.

Through detection, the penetration depth of the organic silicon penetration type protective agent can reach 6-10mm in concrete with the strength of C40, but in the environment of long-term contact with chloride ion salts, such as seafood markets, pavements using low-temperature deicing salt, processing plants producing sodium chloride and the like, because the chloride ion salts erode the concrete permanently, the penetration depth of the concrete salt-resistant protective agent needs to be improved, and a better waterproof salt-resistant effect is achieved.

Disclosure of Invention

In order to improve the penetration depth of the concrete salt-resistant protective agent, the application provides the concrete salt-resistant protective agent.

The application provides a concrete salt-resistant protective agent, adopts following technical scheme:

a concrete salt-resistant protective agent is prepared from the following components in percentage by mass of 1: (200-2000) A component and B component:

wherein the component A is prepared from the following raw materials in parts by weight:

the component B comprises the following raw materials in parts by weight:

0.01-0.1 part of silicone-acrylate emulsion;

the component A in the concrete salt-resistant protective agent is prepared by the following process steps:

p1, weighing sodium alginate with the formula amount, dissolving the sodium alginate in distilled water, and preparing into 0.1-0.5wt% sodium alginate water solution;

p2, weighing the dispersing agent with the formula amount, adding the dispersing agent into the sodium alginate aqueous solution, and uniformly mixing to prepare a mixed solution;

p3, weighing the calcium gluconate with the formula amount, and dissolving the calcium gluconate in distilled water to prepare a calcium gluconate solution;

p4, weighing alkyl siloxane with a formula ratio, adding the alkyl siloxane into the mixed solution obtained in the step P2 under the stirring condition, and performing ultrasonic dispersion at the ultrasonic frequency of 30-60Hz for 0.5-1.5h to prepare an emulsion;

p5, under the condition of adding an electrostatic field, the emulsion is pressurized and sprayed into the calcium gluconate solution, the voltage of the electrostatic field is 500-1800V, the spraying pressure of the emulsion is 4-6MPa, and when the emulsion is sprayed, the mixed solution of the emulsion and the calcium gluconate solution is sprayed and dried to obtain the component A.

According to the technical scheme, sodium alginate is used as a wall material, alkyl siloxane is used as a core material, an oil-in-water emulsion is formed firstly, the atomized particle size of the emulsion is smaller under the electrostatic action generated by an external electrostatic field and the pressurizing action of the emulsion, the particle size of a microcapsule preliminarily formed by adding a curing agent calcium gluconate solution can reach a nanometer level, the preliminarily formed microcapsule with high water content is subjected to spray drying, water loss and volume shrinkage, and the average particle size of the microcapsule particles of the component A in a final drying state is 50 nm;

the component A and the component B are stored separately, the silicone-acrylic emulsion of the component B reacts with the component A in a use state, and the component B is carried out in the internal pores of the concrete along with the component A to promote the formation of an organic silicon network in the concrete salt-resistant protective agent;

the concrete salt-resistant protective agent increases the penetration depth of the concrete salt-resistant protective agent from the following two aspects:

firstly, in the initial stage of penetration, after the alkyl siloxane is coated by the microcapsule, the sodium alginate on the surface of the microcapsule contains a large amount of hydroxyl groups, so that the microcapsule has good compatibility with water, and the average particle size of the microcapsule is 50nm, so that the microcapsule can enter pores in concrete along with water to perform rapid adsorption and penetration, and the initial penetration depth of the concrete salt-resistant protective agent is increased;

secondly, in the later stage of penetration of the concrete salt-resistant protective agent, along with the dissolution of sodium alginate serving as a capsule wall, alkyl siloxane is gradually released, the alkyl siloxane can be hydrolyzed in water to generate silicon hydroxyl, the silicon hydroxyl is crosslinked with alkaline substances such as calcium hydroxide in the concrete, the generated reaction heat enables the water in the concrete to be dissipated, and a hydrophobic film is formed in the concrete.

Preferably, the mass ratio of the sodium alginate to the alkyl siloxane is 1 (0.25-0.5).

By adopting the technical scheme, when the mass ratio of the sodium alginate to the alkyl siloxane is too large, the alkyl siloxane is completely encapsulated by the sodium alginate, the mass ratio of the sodium alginate to the alkyl siloxane is continuously increased, the content of microcapsules encapsulating the alkyl siloxane is unchanged, when the mass ratio of the sodium alginate to the alkyl siloxane is too small, a large amount of alkyl siloxane is attached to the surface of the sodium alginate and is dissolved in alkyl siloxane liquid drops in the sodium alginate and exceeds the coating limit of the sodium alginate, so that the encapsulation efficiency is reduced, namely, the content of active ingredients (microcapsules encapsulating the alkyl siloxane) in the component A of the concrete salt-resistant protective agent is reduced, the permeability of the concrete salt-resistant protective agent is positively correlated with the content of the active ingredients in the component A of the concrete salt-resistant protective agent, the content of the active ingredients is higher, the compatibility of the concrete salt-resistant protective agent with water is better, and, therefore, in the range, the sodium alginate has higher encapsulation efficiency on the alkyl siloxane, the penetration depth of the concrete salt-resistant protective agent is larger, and better waterproof and salt-resistant effects are achieved.

Preferably, the alkyl siloxane is any one or two of octyl triethoxysilane and isobutyl triethoxysilane.

By adopting the technical scheme, the carbon chain number of the alkyl siloxane is too long or too short, so that the emulsification is not facilitated, and the emulsification stability in the emulsion is poor, therefore, the carbon chain number of the octyl triethoxysilane and the isobutyl triethoxysilane is moderate, so that the alkyl siloxane can be stably dispersed in the emulsion to form uniform small droplets, and the emulsion has good emulsification stability and high encapsulation efficiency.

Preferably, the dispersant is fatty amine polyoxyethylene ether or alkyl polyglucoside.

By adopting the technical scheme, the fatty amine polyoxyethylene ether and the alkyl polyglucoside have both hydrophilic groups and lipophilic groups, so that the alkyl siloxane can be stably dispersed in the emulsion to form uniform small droplets, and the encapsulation efficiency is improved.

Preferably, the concentration of the calcium gluconate solution is 0.4 to 1.5 wt%.

By adopting the technical scheme, the larger the concentration of the calcium gluconate solution is, the faster the solidification rate of the sodium alginate is, the alkyl siloxane liquid drops are not easy to dissolve together along with the increase of time, and the emulsion liquid drops can be maintained in a uniform state with smaller diameter, so that the encapsulation rate of the sodium alginate on the alkyl siloxane is increased, namely, the higher the content of the effective components in the concrete salt-resistant protective agent A component is, the better the compatibility with water is, the better the permeability of the concrete salt-resistant protective agent is, the greater the penetration depth is, but when the concentration of the calcium gluconate solution exceeds the range and is continuously increased, the solidification rate of the sodium alginate is almost unchanged, and the encapsulation rate is not influenced.

Preferably, the stirring rate for the addition of the alkylsiloxane in step P4 is 60-100 r/min.

By adopting the technical scheme, the mixed solution formed by the sodium alginate aqueous solution and the emulsifier has higher viscosity, the faster the stirring speed is, the higher the viscosity of the mixed solution is, the dispersion of the alkyl siloxane is not facilitated, but the smaller the stirring speed is, the larger the diameter of liquid drops formed by the dispersion of the alkyl siloxane is, on one hand, the encapsulation rate of the sodium alginate on the alkyl siloxane is reduced, on the other hand, the larger the particle size of the microcapsule is, the diameter of pores in concrete is generally nano-scale, the larger the particle size of the microcapsule is not conducive to the concrete salt-resistant protective agent to enter the concrete, therefore, in the stirring speed range, the alkyl siloxane is uniform and stable small liquid drops, and the improvement of the penetration depth of the.

Preferably, the frequency of ultrasonic dispersion in the step P4 is 40-60Hz, and the time of ultrasonic dispersion is 0.5-1.5 h.

By adopting the technical scheme, the ultrasonic dispersion is beneficial to the dispersion of the alkyl siloxane in the emulsion, the larger the frequency and the longer the time of the ultrasonic dispersion are, the smaller the droplet diameter of the alkyl siloxane is, the dispersion degree is increased, and the better the emulsification effect is, but when the frequency and the time of the ultrasonic dispersion exceed the range, the emulsification effect of the alkyl siloxane is hardly influenced.

Preferably, the voltage of the applied electrostatic field in the step P5 is 1800V, and the spraying pressure is 14 MPa.

By adopting the technical scheme, the emulsion forms uniform small droplets under the action of the electric field force and the external injection pressure, and the primary formed microcapsules have smaller particle size when the small droplets are injected into the curing agent calcium gluconate solution, so that the micro-nano level can be achieved.

Preferably, the spraying pressure of the spray drying in the step P5 is 4-5 MPa.

By adopting the technical scheme, the component A is dried by adopting a spray drying mode, when the spray pressure of the spray drying is too large, the impact times among the microcapsules in the sprayed atomized liquid are increased, the coating film of the microcapsules is easy to break under the action of mechanical shearing force, and the content of the effective components of the component A in the concrete protective agent is reduced, so that the content of the effective components of the component A is higher and the permeability of the concrete salt-resistant protective agent is better under the spray pressure.

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

1. because this application is through adopting sodium alginate to carry out the cladding to alkyl siloxane, forms hydrophilic microcapsule, simultaneously because the slow release effect of microcapsule for alkyl siloxane is prolonged at the inside reaction time of concrete, slows down moisture rate of losing, improves the permeability of concrete salt-resistant protective agent, increases the penetration depth of concrete salt-resistant protective agent, plays better waterproof salt-resistant protection effect, thereby improves the durability of concrete.

2. The means through the voltage of control plus electrostatic field and injection pressure makes the emulsion can fully atomize in this application, and the microcapsule particle diameter that preliminarily forms after getting into the curing agent solidification is less, and follow-up behind spray drying microcapsule shrink, the average particle diameter of final A component microcapsule is at 50nm, improves the permeability of concrete anti-salt protective agent.

Detailed Description

Unless otherwise specified, the starting materials in the following preparations and examples are derived from the following table:

raw materials	Specification of	Source
			Sodium alginate	Food grade, purity 99%	Shanghai research and generation biochemistry
Fatty amine polyoxyethylene ether	AC-1812	Jiangsu Haian petroleum
			Aliphatic polyoxyethylene ether	MOA-3	Jiangsu Haian petroleum
Alkyl polyglucosides	PAG-1214	Guangzhou Baichen chemical industry
			Silicone-acrylic emulsion	PD—6	Shandongboda

Preparation example of A component of concrete salt-resistant protective agent

Preparation example 1

A component A of the concrete salt-resistant protective agent is prepared according to the following process steps:

1. weighing 10000g of distilled water, preheating to 60 ℃, weighing 10g of sodium alginate, adding the sodium alginate into the hot distilled water, stirring uniformly at the stirring speed of 150r/min for 15min, and preparing into a sodium alginate aqueous solution with the concentration of 0.1 wt%;

2. weighing 2.1g of dispersant aliphatic polyoxyethylene ether MOA-3, adding into 0.1 wt% of sodium alginate aqueous solution, stirring and mixing at the stirring speed of 150r/min for 5min to prepare mixed solution;

3. weighing 3g of calcium gluconate, adding into 200g of distilled water, stirring uniformly at the stirring speed of 150r/min for 15min to prepare a 1.5wt% calcium gluconate solution;

4. weighing 10g of alkyl siloxane monomer, selecting dodecyl triethyl silane from the alkyl siloxane monomer, stirring and adding the dodecyl triethyl silane into the mixed solution, wherein the stirring speed is 150r/min, immediately performing ultrasonic dispersion after the addition of the dodecyl triethyl silane is finished, the ultrasonic frequency is 30Hz, and the ultrasonic time is 0.5h, so as to prepare an emulsion;

5. transferring the emulsion into an electrostatic sprayer, setting the voltage of the electrostatic sprayer to be 500V, and the spraying pressure to be 10MPa, and continuously spraying the emulsion into a calcium gluconate solution through a nozzle;

6. when the emulsion is sprayed completely, continuously pumping the mixed solution of the emulsion and the calcium gluconate solution into a spray dryer for spray drying, wherein the spraying pressure of the mixed solution of the emulsion and the calcium gluconate solution is 6MPa, the air flow temperature of an air inlet is 120 ℃, and the air flow rate is 2000m³And h, obtaining microcapsule particles of the component A after spray drying, wherein the average particle size is 50 nm.

Preparation examples 2 to 7

A component A of the concrete salt-resistant protective agent is prepared on the basis of preparation example 1, and is different from the preparation example 1 in that: the formula of the component A is different, and the specific formula is shown in the following table 2:

TABLE 2 formulation differences of component A

Components	Preparation example 2	Preparation example 3	Preparation example 4	Preparation example 5	Preparation example 6	Preparation example 7
							Dodecyl triethyl silane (g)	1	3	5	5.6	7.5	9
Sodium alginate (g)	20g	20g	20g	15g	15	10
							Aliphatic polyoxyethylene ether MOA-3(g)	2.4	2.4	2.9	2.1	2.4	2.9
Calcium gluconate (g)	3	3.5	4	3.5	3.5	3.5

Preparation examples 8 to 10

A component A of the concrete salt-resistant protective agent is prepared on the basis of preparation example 5, and is different from the preparation example 5 in that:

the dodecyltriethoxysilane in preparation example 8 was replaced with an equal mass of octyltriethoxysilane;

the dodecyltriethoxysilane in preparation example 9 was replaced with isobutanyltriethoxysilane of equal mass;

the dodecyltriethoxysilane in preparation example 10 was replaced with an equal mass of a mixture of octyltriethoxysilane and isobutyltriethoxysilane, wherein octyltriethoxysilane and isobutyltriethoxysilane were mixed in a mass ratio of 1: 1.

Preparation examples 11 to 12

A component A of a concrete salt-resistant protective agent is prepared on the basis of preparation example 10, and is different from preparation example 10 in that:

the aliphatic polyoxyethylene ether MOA-3 of the dispersant in the preparation example 11 is replaced by aliphatic amine polyoxyethylene ether AC-1812 with equal mass;

the dispersant aliphatic polyoxyethylene ether MOA-3 in preparation example 12 was replaced with an equal mass of alkylpolyglucoside PAG-1214.

Preparation examples 13 to 15

A component A of a concrete salt-resistant protective agent is prepared on the basis of preparation example 12, and is different from preparation example 12 in that:

the concentration of the aqueous sodium alginate solution in step 1 in preparation example 13 was 0.25 wt%;

the concentration of the aqueous sodium alginate solution in step 1 in preparation example 14 was 0.5 wt%;

preparation examples 15 to 16

A concrete salt-resistant protective agent is prepared on the basis of preparation example 14, and is different from preparation example 14 in that:

the concentration of the calcium gluconate solution in step 3 of preparation example 15 was 0.9 wt%;

the concentration of the calcium gluconate solution in step 3 of preparation example 16 was 1.5 wt%.

Preparation examples 17 to 19

A component A of a concrete salt-resistant protective agent is prepared on the basis of preparation example 15, and is different from preparation example 15 in that:

preparation example 17 the stirring rate at the time of addition of the alkylsiloxane in step 4 was 60 r/min;

preparation example 18 the stirring rate at the time of addition of the alkylsiloxane in step 4 was 80 r/min;

preparation example 19 the alkylsiloxane was added at a stirring rate of 100r/min in step 4.

Preparation examples 20 to 22

A component A of a concrete salt-resistant protective agent is prepared on the basis of preparation example 18, and is different from preparation example 18 in that: the ultrasonic conditions in step 4 are different, and the specific values are shown in the following table 3:

TABLE 3 ultrasonic conditions

Preparation example	Ultrasonic frequency (Hz)	Ultrasonic time (h)
			Preparation example 20	40	1.5
Preparation example 21	50	1.0
			Preparation example 22	60	0.5

Preparation example 23

A component A of a concrete salt-resistant protective agent is prepared on the basis of preparation example 22, and is different from preparation example 22 in that: the electrostatic field voltage set in step 5 was 1800V and the spray pressure was 14 MPa.

Preparation examples 24 to 26

A component A of a concrete salt-resistant protective agent is prepared on the basis of preparation example 23, and is different from preparation example 23 in that: the spraying pressure of the spray drying in the step 6 is different, and the specific numerical values are shown in the following table 4:

TABLE 4 spray drying spray pressure

Preparation example	Spray pressure (MPa) of spray dryer
		Preparation example 24	4
Preparation example 25	5.5
		Preparation example 26	6

Examples

Example 1

A concrete salt-resistant protective agent is prepared by the following steps:

0.01g of silicone-acrylic emulsion PD-6 and 20g of the component A prepared in the preparation example 1 are weighed and added into 100g of distilled water, and the mixture is stirred and mixed evenly to prepare the concrete salt-resistant protective agent.

Examples 2 to 3

A concrete salt-resistant protective agent is prepared on the basis of example 1, and is different from example 1 in that: the addition amount of the silicone-acrylic emulsion PD-6 is different, and the specific numerical values are shown in the following table 5:

TABLE 5 addition of Silicone acrylic emulsion PD-6

Examples	Adding amount (g) of silicone-acrylic emulsion PD-6
		Example 2	0.05
Example 3	0.1

Examples 4 to 28

A concrete salt-resistant protective agent is prepared on the basis of example 3, and is different from example 3 in that: the A component has different sources, and the specific values are shown in the following table 6:

TABLE 6 sources of A Components

Comparative example

Comparative example 1

The concrete salt-resistant protective agent is prepared by the following process steps:

weighing 10g of dodecyl triethoxysilane, 0.01g of silicone-acrylate emulsion PD-6 and 2.1g of dispersant aliphatic polyoxyethylene ether MOA-3, adding into 500g of distilled water, stirring uniformly at the stirring speed of 150r/min, and performing ultrasonic mixing at the ultrasonic frequency of 30Hz for 0.5h to obtain the concrete salt-resistant protective agent.

Performance test

Preparing a concrete sample with the strength of C40 according to the national standard, wherein the specification of the sample is 100mm multiplied by 100mm, and after curing for 28 days, cleaning and drying the surface;

using examples 1 to 28 and comparative example 1, samples were sprayed in a horizontal plane in an amount of 300g/m²Air drying after 24 hr, repeatingAnd (5) drying for 24 hours in the second step, and then curing for 4d, and carrying out the following performance detection.

Detection method penetration depth: and (4) detecting the penetration depth according to a penetration depth test method (a dyeing method) in JTJ275-2000, and recording the penetration depth of the concrete salt-resistant protective agent.

Water absorption reduction rate: testing the water absorption of the blank concrete sample, the concrete samples of coating examples 1-28 and the concrete sample of coating comparative example 1 according to the water absorption detection method in JTJ275-2000, and changing the water for detection into a sodium chloride aqueous solution with the concentration of 0.1 wt%;

reduction rate of chloride ion absorption: the concrete samples of coating examples 1 to 28 and the concrete sample of coating comparative example 1 were tested for chloride ion absorption reduction rate according to the method for detecting water absorption in JTJ275 to 2000, respectively.

And (3) detecting the compressive strength of the concrete:

environmental simulation: the ST-BZ-7 salt spray test box is used for carrying out long-term chloride ion environmental simulation, the concentration of sodium chloride salt water in the salt spray test box is 5wt%, and the sedimentation amount of the salt spray is 2mL/80 (cm)²H), run 24 h;

the blank concrete samples, the concrete samples of coating examples 1 to 28 and the concrete sample of coating comparative example 1 were placed in the salt spray test box for environmental simulation, and after the simulation was completed, the samples were taken out and the concrete compressive strength was tested according to GB 50204-2002.

Detecting data

TABLE 7 concrete salt-resistant protectant Performance test

TABLE 8 compressive Strength of concrete

The larger the value of the water absorption rate reduction rate is, the better the waterproof effect of the concrete salt-resistant protective agent is;

the larger the concrete chloride ion absorption reduction rate is, the better the salt resistance of the concrete salt-resistant protective agent is; the concrete compressive strength indirectly reflects the durability of the salt-resistant protective agent of the coated concrete: the compressive strength of the concrete sample with the strength of C40 before being corroded by salt ions is 44.9MPa, and when the concrete sample coated with the concrete salt-resistant protective agent can be corroded continuously by chloride ions for a period of time, the compressive strength is slightly reduced, but is far higher than that of the blank sample which is not coated with the concrete salt-resistant protective agent, so that the concrete salt-resistant protective agent can effectively improve the durability of concrete.

Data analysis

Combining example 1 and comparative example 1 and table 7, it can be seen that the conventional silicone-based penetration protective agent in comparative example 1 has an alkylsiloxane as an active ingredient, but the alkylsiloxane is not coated, the penetration depth of the concrete salt-resistant protective agent in the concrete with the strength of C40 is 8.2mm, the concrete water absorption rate reduction rate is 89.5%, and the concrete chloride ion absorption rate reduction rate is 71.0%; after sodium alginate is used for coating in the embodiment 1, the penetration depth of the concrete salt-resistant protective agent in the concrete with the strength of C40 is improved from 8.2mm to 12.9mm, the water absorption reduction rate of the concrete is improved from 89.5% to 92.9%, and the chloride ion absorption reduction rate of the concrete is improved from 71.0% to 91.9%;

therefore, sodium alginate coats alkyl siloxane, and the formed microcapsule can effectively improve the penetration depth of the concrete protective agent in the concrete, and improve the water absorption reduction rate and the chloride ion absorption reduction rate of the concrete;

secondly, as can be seen from the test data of the compressive strength of the concrete shown in table 7, the compressive strength of the concrete sample of coating example 1 after simulating the continuous erosion of the chloride salt is greater than that of the concrete sample of coating comparative example 1, which can effectively improve the durability of the concrete.

As can be seen by combining examples 1 to 28 with table 8, the depth of penetration of the concrete salt-resistant protective agent increases, and the greater the compressive strength of the concrete coated with the concrete salt-resistant protective agent, the greater the penetration depth of the concrete salt-resistant protective agent can improve the durability of the concrete under the continuous erosion of the chloride salt, as compared with the blank sample.

As can be seen by combining examples 1-3 and Table 7, the increase of the amount of the component B does not affect the permeability of the concrete salt-resistant protective agent, but the water absorption reduction rate and the chloride ion absorption reduction rate are improved, so that the component B is proved to be capable of promoting the formation of an organosilicon network and improving the waterproof and salt-resistant effects of the concrete salt-resistant protective agent.

It can be seen from the combination of examples 3-10 and table 7 that when the mass ratio of sodium alginate to alkyl siloxane is 1:0.265, the encapsulation efficiency is highest, the penetration depth of the concrete salt-resistant protective agent with the highest content of the active ingredients in the prepared component A is increased from 13.0mm to 14.9mm, the water absorption reduction rate is increased from 94.1% to 97.4%, the chloride ion absorption reduction rate is increased from 93.2% to 93.8%, and the waterproof and salt-resistant effects of the concrete salt-resistant protective agent are improved.

It can be seen from the combination of examples 24-28 and table 7 that the proper atomization mode can improve the penetration depth of the concrete salt-resistant protective agent, and the concrete salt-resistant protective agent has better waterproof and salt-resistant effects.

As can be seen by combining examples 1-28 with tables 7-8, the best method for preparing a concrete salt-resistant protective agent is example 27.

The specific preparation examples are only for explaining the application and are not limiting to the application, and those skilled in the art can make modifications without inventive contribution to the preparation examples as required after reading the specification, but are protected by patent laws within the scope of the claims of the application.

Claims

1. The concrete salt-resistant protective agent is characterized by comprising the following components in percentage by mass of 1: (200-2000) A component and B component:

1-10 parts of alkyl siloxane

10-20 parts of sodium alginate

3-4 parts of calcium gluconate

2.1-2.9 parts of a dispersant;

the component B comprises the following raw materials in parts by weight:

0.01-0.1 part of silicone-acrylate emulsion;

2. The concrete salt-resistant protective agent as claimed in claim 1, wherein the mass ratio of sodium alginate to alkane siloxane is 1 (0.25-0.5).

3. The concrete salt-resistant protective agent according to claim 2, wherein the alkylsiloxane is any one or two of octyl triethoxysilane and isobutyl triethoxysilane.

4. The concrete salt-resistant protective agent according to claim 3, wherein the dispersant is fatty amine polyoxyethylene ether or alkyl polyglucoside.

5. The concrete salt-resistant protective agent according to claim 4, wherein the concentration of the calcium gluconate solution is 0.4-1.5 wt%.

6. The concrete salt-resistant protective agent according to claim 5, wherein the stirring rate of the alkylsiloxane added in step P4 is 60-100 r/min.

7. The concrete salt-resistant protective agent according to claim 6, wherein the ultrasonic dispersion frequency in the step P4 is 40-60Hz, and the ultrasonic dispersion time is 0.5-1.5 h.

8. The concrete salt-resistant protective agent according to claim 7, wherein the applied electrostatic field voltage in step P5 is 1800V, and the spraying pressure is 14 MPa.

9. The concrete salt-resistant protective agent according to claim 8, wherein the spraying pressure of the spray drying in the step P5 is 4-5 MPa.