KR100274357B1 - High capability fluidizing agent for cement using surfactant compound based on polycarbonic acid and method for producing the same - Google Patents

Abstract

PURPOSE: Provided are a high capability fluidizing agent for cement which shows a low slump loss and an improved strength property when mixed with cement, and a method for producing the same. CONSTITUTION: The fluidizing agent is produced by the steps of (i) mixing 1.3-1.5 parts by weight of aqueous triethanol amine(TEA) containing 45-55% of TEA and 55-60 parts by weight of aqueous lignin containing 80-85% of lignin powder, (ii) adding 0.3-0.5 parts by weight of preservative and 2-3 parts by weight of fructose to the mixture from the step(i) with stirring, (iii) adding 30-35 parts by weight of aqueous naphthalene sulfonic acid formalin condensate to the mixture from the step(ii) with stirring, and (iv) sequentially adding 3-5 parts by weight of aqueous copolymer containing 70-80% of copolymer compound(represented by formula 1) based on polycarbonic acid and 3-5 parts by weight of water into the mixture from the step(iii) with stirring. In the formula 1, A represents O-Na+ or the following formula, n is an integer of 2-6.

Description

FLUIDITY-IMPROVING AGENT FOR CEMENT AND THE METHOD OF PRODUCING THE SAME USING POLYCARBONIC ACID COMPOUNDS

The present invention relates to a high fluidizing agent for cement using a polycarboxylic acid-based surfactant compound and a method for preparing the same, and more specifically, to a polycarboxylic acid type represented by Formula 1 below by sulfated styrene-maleic anhydride copolymerized compound Using a surfactant compound, a method for producing a high fluidizing agent for cement that can exhibit high strength characteristics with low slump prosperity and excellent absorption and adsorption rate when mixed with cement, and a high performance fluidizing agent for cement prepared therefrom It is about.

In Formula 1, A is O ^- Na ⁺ or And n is an integer from 2 to 6.

In recent years, due to the rapid development of the industrial society, the increase in the size and height of building structures has increased the use of a pressure pump to facilitate the transport and pouring of concrete during construction.

However, this concrete has a very low workability and causes difficulties such as frequent clogging of the pump during pump feeding and excessive energy consumption. Therefore, it is necessary to add excess water to the concrete to increase fluidity. By increasing the workability at the time of transport and pouring, but in this case the problem of inevitably deteriorating the strength of the hardened concrete has a serious adverse effect on the durability of the concrete.

In order to solve the above problems, the conventional method for satisfying the strength characteristics and workability by reducing the number of units contained in the concrete in order to prevent the degradation of the strength characteristics due to excess moisture added during the production of concrete As part of the process, the fluidizing agent compounds, which are classified as organic acid compounds such as lignin-based, naphthalene-based, melamine-based or iminosulfonic acid-based compounds, were selected and mixed with concrete at the appropriate time.

However, the above-mentioned conventional lignin-based, naphthalene-based, melamine-based or organic acid-based compounds are not so sensitive, and it is not easy to control the sensitivity, so that even when the amount of the fluidizing agent is increased, the effect of increasing the sensitivity is higher than a certain value. Not only that, but also depending on the amount added, problems such as poor cement hardening characteristics were generated.

In addition, the polymers such as naphthalene-based, melamine-based are adsorbed to the cement particles used as binders in the production of concrete, such cement particles are not inert but fine particles having a great activity of hydration reaction over time, cement particles Since the polymer material adsorbed onto the surface becomes entangled with the hydrate and thus becomes electrically neutral, the electrostatic repulsion and the three-dimensional repulsive force are lowered and the balance is destroyed, so finally, van der Waals attraction is predominant, and the slump loss begins to aggregate. As the phenomenon worsens, not only the dispersibility of cement particles is lowered, but there is a problem that seriously affects the strength of concrete after curing.

The present invention is to solve the above problems, in the fluidizing agent used as a cement admixture, a high-functional surfactant with a conventional lignin-based, naphthalene-based, melamine-based or aminosulfonic acid-based compound It is a polycarboxylic acid copolymer (styrene-maleic acid copolymer) compound and other additives prepared by mixing in an appropriate ratio to provide a high fluidizing agent to greatly improve the slumping phenomenon and to greatly improve the dispersion stability and sensitivity after curing It is an object of the present invention to provide a high fluidizing agent for cement using a polycarboxylic acid-based surfactant compound that can significantly improve the strength of concrete, and a method of manufacturing the same.

The present invention for achieving the above object, 1.3 to 1.5 parts by weight of TEA aqueous solution mixed with 45 to 55% TEA (triethanolamine, hereinafter TEA) and 55 to 60 parts by weight of lignin aqueous solution mixed with 80 to 85% lignin powder After mixing the parts, the mixture was stirred by adding 0.3 to 0.5 parts by weight of preservative and 2-3 parts by weight of fructose, and then adding 30 to 35 parts by weight of the aqueous solution of naphthalene sulfonic acid formalin condensate mixed with 55% to 65% naphthalene sulfonic acid formalin condensate. After stirring, 3 to 5 parts by weight of the aqueous solution of the copolymer in which the polycarboxylic acid-based copolymer compound represented by the following general formula (1) is mixed at 70 to 80% is added, and then 3 to 5 parts by weight of water is added to the mixture to stir again. Provided are a method for producing a high fluidizing agent for cement using a polycarboxylic acid-based surfactant compound, and a high leveling agent prepared therefrom.

<Formula 1>

In Formula 1, A is O ^- Na ⁺ , or … … And n is an integer from 2 to 6.

The TEA is added as a sensitivity control agent in consideration of the miscibility with other additives to be added in an aqueous solution of 45 to 55%, the addition amount is 1.3 parts by weight based on 55 to 60 parts by weight of the lignin aqueous solution If it is added below it can not exhibit a desirable sensitivity control function, it is not necessary to add more than 1.5 parts by weight.

The added lignin coexists with fibrin in woody fibrous cells and occupies about 30% of wood, and is used as a raw material for cement high fluidizing agent by using lignin powder obtained as a by-product from pulp industry. do.

The lignin powder thus prepared is preferably mixed and prepared in an aqueous solution in order to achieve uniform mixing with other additives. The concentration of the lignin powder in the aqueous solution is 80 wt% or more but not less than 85 wt%. It is preferable to add too much so that a viscosity may not become large more than necessary.

The addition amount of the lignin aqueous solution is added to 55 parts by weight or more in consideration of the retention of concrete, but does not need to be added in excess of 60 parts by weight.

Since the lignin powder as described above is a natural substance, the decay may progress with time, and thus, in the case of the fluidizing agent prepared by mixing it, there is a problem in storage properties, and thus, preservatives are added to improve the preservative. Preservatives for cement admixtures can be used and typically compounds such as benzoic acid or formalin can be used.

When the preservative is less than 0.3 part by weight based on 55 to 60 parts by weight of the aqueous lignin solution, the desired antiseptic effect cannot be obtained, and it is not necessary to add more than 0.5 parts by weight.

Fructose added in the present invention is a kind of polysaccharides such as starch syrup commonly used for delaying the coagulation of cement. It is preferable to use a solubility in water as much as possible. When added, the problem of condensation delay becomes too large.

The above-mentioned naphthalene sulfonic acid formalin condensate is added to show fluidity when mixed with concrete, and when it is added less than 30 parts by weight, a desirable fluidity increase effect cannot be expected, and when added in excess of 35 parts by weight Further increase in effect is very minimal in terms of the addition in the range of 30 to 35 parts by weight.

Along with this, the styrene-maleic acid copolymer compound of Chemical Formula 1 added during the preparation of the high-flowing agent for cement of the present invention is a polycarboxylic acid compound exhibiting surfactant activity, and it is mixed within the above-mentioned range in the preparation of the fluidizing agent. This will greatly improve the fluidity and by adsorbing on the surface of the cement material when mixing with the cement binder to increase the dispersibility to prevent the aggregation of cement particles and to reduce the loss of slump over time as well as to hydrate the cement It is possible to produce high-strength concrete by promoting.

The compound of Formula 1 is prepared in the sodium salt state by copolymerizing styrene and maleic anhydride, followed by treatment with sulfuric acid, fuming sulfuric acid, and the like to form a sulfate, followed by reaction with sodium hydroxide. before performing sulfation during the production process of styrene-maleic acid copolymer can be produced by giving reacted with compounds such as m- aminophenol, these polycarboxylic acid-based compound of formula 1 of a is O ^- Na ⁺ or More preferred are compounds of formula (2) or (3).

In order to prepare the compound of Chemical Formula 2, various known methods may be applied. For example, styrene, maleic anhydride, and azobis (isobutyronitrile) may be dissolved in benzene and stirred to After obtaining a styrene-maleic anhydride copolymer compound of Formula 4, and reacting it with sulfuric acid and fuming sulfuric acid to produce a compound of the formula (5), and then mixed with an aqueous solution of calcium hydroxide to prepare a sodium salt of the formula (2) Can be.

In addition, as a method for preparing the compound of Formula 3, styrene, maleic anhydride, and azobis (isobutyronitrile) (azobis (isobutyronitrile)) are dissolved in benzene and stirred to form the styrene-maleic anhydride copolymer of Formula 4 After obtaining a compound to react with m-aminophenol to obtain a compound of formula (6), and then reacted with sulfuric acid and fuming sulfuric acid to form a compound of the formula (7) and then mixed with a calcium hydroxide solution It can be prepared by the sodium salt of formula (3).

In Formulas 4 to 7 n is an integer of 2 to 6.

In the preparation of the polycarboxylic acid-based surfactant copolymer solution, by adding an appropriate amount of acidity regulator such as sodium hydroxide to adjust the pH to an alkalinity of 8 or more, the sensitizing effect can be further activated. If it becomes larger, rather than causing a decrease in the water effect, it is recommended that the pH is not larger than 8.5 or more.

The polycarboxylic acid-based surfactant is also added in an aqueous solution state of 70 to 80% in consideration of miscibility with other additives, in which at least 3 parts by weight is added based on 45 to 55 parts by weight of the lignin aqueous solution. However, it is not necessary to add more than 5 parts by weight.

The high fluidizing agent of the present invention prepared by the method as described above is used by mixing at least 0.3% of the weight of the cement, it is preferable that the addition amount does not exceed 1% to avoid the phenomenon that the initial curing is delayed.

Hereinafter, the method for preparing the high fluidizing agent of the present invention as described above will be described in more detail with reference to the following examples.

<Preparation Example 1 of Polycarboxylic Acid-Based Surfactant Compound>

52 g of 2000 g of three-necked plasma styrene, 49 g of maleic anhydride, and 1.64 g of azobis (isobutyronitrile) were dissolved in 500 ml of benzene, and the reaction was carried out for 2 hours while stirring at 350 rpm using a mechanical stirrer at 70 ° C. to synthesize a white precipitate. Got. The compound was separated by suction filtration through filter paper and then vacuum dried for 48 hours. The dried compound was again dissolved in tetrahydrofuran, reprecipitated in diethyl ether, separated, and then vacuum dried at 60 ° C. for 48 hours to obtain 75 g of styrene-maleic anhydride copolymer.

Subsequently, 20 g of the above-described styrene-maleic anhydride copolymer and 200 g of sulfuric acid were added to a 1000 ml three-necked flask, and stirred at 55 ° C. using a mechanical stirrer for 40 minutes to dissolve. Then, the temperature was cooled to room temperature, 35 ml of fuming sulfuric acid was added, and heated again. After reacting at 45 ° C., the temperature was lowered to room temperature again, the reaction mixture was diluted with 250 ml of distilled water, 200 ml of calcium hydroxide solution was added dropwise, precipitated unreacted sulfuric acid with salt, and filtered by suction with a filter paper. The main acid-based surfactant compound was prepared. Sodium hydroxide was added dropwise thereto to adjust the pH to 8-8.5.

<Polycarboxylic Acid Surfactant Compound Preparation Example 2>

In a 2000 ml three-necked flask, 52 g of styrene, 49 g of maleic anhydride, and 1.64 g of azobis (isobutyronitrile) were dissolved in 500 ml of benzene, and then reacted for 2 hours while stirring at 350 rpm using a mechanical stirrer at 70 ° C. to obtain a white precipitate. Got. The compound was separated by suction filtration through filter paper and then vacuum dried for 48 hours. The dried compound was again dissolved in tetrahydrofuran, reprecipitated in diethyl ether, separated, and then vacuum dried at 60 ° C. for 48 hours to obtain 75 g of styrene-maleic anhydride copolymer.

Subsequently, 35 g of the styrene-maleic anhydride copolymer was dissolved in 250 ml of dimethylformamide in a 1000 ml three-neck flask, and 250 ml of m-aminophenol was dissolved in dimethylformamide in advance. It was dripped over 1 hour, maintaining for 30 minutes, and reacted again at room temperature for 3 hours. After completion of the reaction, the solution was poured into diluted hydrochloric acid solution, precipitated, filtered by suction, washed several times with deionized water and dried to prepare a polycarboxylic acid-based surfactant compound having a structure of 3 in the above chemical. Sodium hydroxide was added dropwise thereto to adjust the pH to 8-8.5.

<Example 1>

After adding and stirring 89.5 kg of TEA and 22.4 liters of water, and further adding 65 liters of TEA solution prepared by adding 22.4 liters of water, 760 kg of lignin powder and 2000 liters of water were mixed, and then slowly stirred to form a complete solution. Then, 14 kg of formalin 60% solution and 100 kg of starch syrup were slowly added while stirring was continued.

Subsequently, 600 kg of naphthalene sulfonic acid formalin condensate and 1000 liters of water were added thereto, followed by mixing, followed by mixing 165 kg of the copolymer prepared by the method shown in Preparation Example 1 of the polycarboxylic acid-based surfactant compound, followed by stirring at low speed. .

Finally 169 liters of additional water was added and stirred for 1 hour.

<Example 2>

After adding and stirring 89.5 kg of TEA and 22.4 liters of water, and further adding 65 liters of TEA solution prepared by adding 22.4 liters of water, 760 kg of lignin powder and 2000 liters of water were mixed, and then slowly stirred to form a complete solution. Then, 14 kg of formalin 60% solution and 100 kg of starch syrup were added slowly as preservatives and the stirring was continued.

Subsequently, 600 kg of naphthalene sulfonic acid formalin condensate and 1000 liters of water were added and mixed, and then 165 kg of the copolymer prepared by the method shown in Preparation Example 2 of the polycarboxylic acid-based surfactant compound was mixed and then added with stirring at low speed. .

Finally 169 liters of additional water was added and stirred for 1 hour.

Experimental Example

The concrete composition was prepared by mixing 162 kg of water, 300 kg of cement, 799 kg of sand, and 1037 kg of gravel, and then mixed 0.2 wt% of the high-performance fluidizing agent of the present invention prepared from Examples 1 to 2, and then determined by KS F 2560. The ratio of the slump and the amount of air and the amount of bleeding, the sensitization rate, the difference in the settling time and the compressive strength ratio were measured and shown in Table 1 below.

Comparative Experimental Example

A concrete composition was prepared by mixing 188 kg of water, 300 kg of cement, 833 kg of sand, and 997 kg of gravel, and then the ratio of slump and air flow over time, gliding ratio, erosion rate, difference in settling time, and compressive strength ratio according to KS F 2560. Was measured and shown in Table 1 below.

division Slump (cm) Air volume (%) Ratio of gliding amount (%) % Reduction Experimental Example 12 4.0 61 14 Comparative Experiment 8.0 1.5 58 12

As can be seen from the results of Table 1 above, the polycarboxylic acid-based surfactant of the present invention had a slump of 12 cm and a susceptibility of 14% in the case of adding the high-performance fluidizing agent prepared from the embodiment of the present invention. In the case of the fluidizing agent not added, the change in slump over time was 8.0 cm and the reduction rate was 12%, indicating that the slump retention effect and the reduction effect were greatly improved in the high performance fluidizing agent of the present invention.

As described above, the present invention is a polycarboxylic acid copolymer which is a kind of high-functional surfactant together with organic acid compounds of lignin-based, naphthalene-based, melamine-based or aminosulfonic acid-based compounds, which have been used as fluidizing agents used as cement admixtures. A polycarboxylic acid system that provides a high fluidizing agent prepared by mixing a compound and other additives in an appropriate ratio to greatly improve the slump pros and to greatly improve the dispersion stability and sensitivity, thereby significantly improving the strength of concrete after curing. It is a useful invention to provide a high fluidizing agent for cement using a surfactant compound and a method for producing the same.

Claims (5)

1.3 to 1.5 parts by weight of TEA aqueous solution mixed with 45 to 55% of TEA (triethanolamine, hereinafter TEA) and 55 to 60 parts by weight of lignin solution mixed with 80 to 85% of lignin powder, and then 0.3 to 0.5 parts by weight of preservative 2 to 3 parts by weight of fructose was added and stirred, followed by stirring while adding 30 to 35 parts by weight of an aqueous solution of naphthalenesulfonic acid formalin condensate mixed with 55 to 65% naphthalenesulfonic acid formalin condensate, followed by general formula (1) The polycarboxylic acid-based surfactant compound, characterized in that 3 to 5 parts by weight of the aqueous solution of the copolymer mixed with 70 to 80% of the mixture is added, and then 3 to 5 parts by weight of water is added and stirred. Method for producing a high fluidizing agent for cement using. <Formula 1> In Formula 1, A is O ^- Na ⁺ or And n is an integer from 2 to 6. The method according to claim 1, wherein A in Formula 1 is O ^- Na ⁺ . The method of claim 1, wherein in Formula 1 A A method for producing a high fluidizing agent for cement using a polycarboxylic acid-based surfactant compound, characterized in that. The method of claim 3, wherein the pH of the copolymer solution is 8 to 8.5. 1.3 to 1.5 parts by weight of TEA aqueous solution mixed with 45 to 55% of TEA (triethanolamine, hereinafter TEA) and 55 to 60 parts by weight of lignin solution mixed with 80 to 85% of lignin powder, and then 0.3 to 0.5 parts by weight of preservative 2 to 3 parts by weight of fructose was added and stirred, followed by stirring while adding 30 to 35 parts by weight of an aqueous solution of naphthalenesulfonic acid formalin condensate mixed with 55 to 65% naphthalenesulfonic acid formalin condensate, followed by general formula (1) A high fluidizing agent for cement, wherein the polycarboxylic acid-based copolymer compound is prepared by adding 3 to 5 parts by weight of an aqueous solution of a copolymer mixed with 70 to 80%, and then adding 3 to 5 parts by weight of water and stirring. <Formula 1> In Formula 1, A is O ^- Na ⁺ or And n is an integer from 2 to 6.