KR101641536B1 - Hybrid polymer binder composition including inorganic and organic polymer, conctrete composition and structure using the same - Google Patents

Abstract

Provided are a hybrid polymer binder composition, a concrete composition using the binder composition, and secondary products such as a drain pipe using the concrete composition, or the like. According to the present invention, the hybrid polymer binder composition forms an inorganic polymer (geopolymer) using an inorganic-based binder, and at the same time uses an organic polymer. A mixture of the geopolymer and the organic polymer has excellent chemical resistance, and thus is a suitable material for conditions which easily induce corrosion of a structure by penetration of acid through a drain pipe, or the like. Also, the mixture improves mechanical strength such as flexural strength, brittleness, and the like, thereby enhancing durability of the structure subject to apply the mixture.

Description

TECHNICAL FIELD [0001] The present invention relates to a hybrid polymer binder composition comprising a combination of an inorganic polymer and an organic polymer, a concrete composition and a structure using the hybrid polymer binder composition,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a binder composition widely used for construction and civil engineering.

The cone creek hume pipe is buried underground and used as a sewage line. Sewer pipes buried in the basement or conduits where the cable is installed are concrete hump pipes or culvert. In the case of an agricultural channel, it is not an entirely closed form like a hume pipe, but an open channel in the upper part and also uses concrete as a material.

Sewage pipes should have good chemical resistance. Sewage pipes are not only easily corroded because they are in constant contact with contaminated water, but also microorganisms in sewage, especially, generate sulfuric acid to promote corrosion of the inner wall of the sewer. However, conventional concrete hume pipes using cement as a main material have problems in that they are excellent in strength, but are easily corroded and aged due to weak chemical resistance.

Conventionally, a concrete hume pipe used as a sewer pipe has a corrosion rate much faster than the period of use. Sewage is leaked to the outside, polluting nearby soil and ground water, and deteriorating living environment. Therefore, the maintenance cost of sewage pipes is consuming a great deal of cost each year, and the inconvenience is increased because repair work for culverts located at the bottom of roads involves traffic control.

In some cases, cement compositions having improved chemical resistance were used, but not only the desired results were obtained, but they were not economical due to the addition of additives.

On the other hand, Hume pipes which are used as a binder by adding the by-products of coal-fired power plant such as fly ash and blast furnace slag powder to the cement have been developed. In these cases, the chemical resistance is increased but the curing hardening is slow and the initial strength is low. The productivity is low, the bending strength is low, and the brittleness is high, so that the impact resistance is poor.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a binder composition and a concrete composition which are excellent in durability, namely, excellent chemical resistance, crack resistance, bending strength and chlorine ion penetration resistance, Sewer pipes, conduits, and repair channels.

On the other hand, other unspecified purposes of the present invention will be further considered within the scope of the following detailed description and easily deduced from the effects thereof.

In order to accomplish the above object, the present invention provides a cement-free cement composition comprising: an inorganic binder forming a geopolymer; A surfactant for improving the workability of the organic polymer; An alkali activator which causes a geopolymer reaction of the inorganic binder; And an organic polymer for improving the chemical resistance and bending strength of the geopolymer.

In one embodiment of the present invention, the inorganic binder includes at least one of fly ash, slag and meta kaolin, silica fume, and bottom ash pulverized fine powder, or natural pozzolanic substances may be used alone or in combination.

In another embodiment of the present invention, the inorganic binder may use a rejected ash containing 5% or more of unburned carbon content.

In the present invention, the organic polymer may be an aqueous dispersion polymer, or an environmentally friendly vinyl acetate ethylene (Vinyl Acetate-Ethylene) may be used. Of course, various polymers such as acrylic, SBR, and latex can be used in addition to VAE.

The alkali activator to trigger the geo-polymer reaction in the present invention include sodium silicate and sodium hydroxide, more specifically the molar ratio of Na ₂ O with respect to the inorganic binder and SiO ₂ in the alkali activator is mixed state (Na ₂ O / SiO ₂ ) is preferably in the range of 0.5 to 3.0.

In one embodiment of the present invention, 20 to 80 parts by weight of the alkali activator and 1 to 20 parts by weight of the organic polymer may be mixed with 100 parts by weight of the inorganic binder and 100 parts by weight of the inorganic binder.

Meanwhile, the concrete composition according to the present invention is characterized by being a hybrid polymer binder composition comprising a binder composition and an aggregate, wherein the binder composition is an organic polymer and an inorganic polymer.

The present invention discloses a high-durability concrete structure having improved chemical resistance and flexural strength by using the concrete composition, and specifically provides a sewer pipe, a repair channel, and a conduit.

The present invention provides a hybrid polymer binder composition comprising an inorganic polymer binder and an organic polymer.

In the present invention, when a sewer pipe is manufactured using cement in combination with an inorganic binder and an organic binder, the problem of chemical resistance, which has been pointed out as a weak point, can be solved.

In the present invention, it is possible to solve the problem of reduction in brittleness and flexural toughness, which has been pointed out as a weak point in manufacturing a sewer pipe using only the cement-based inorganic binder by using the organic polymer.

In the present invention, in order to solve the problem that the buffering property against freeze-thaw deteriorates and the use of the pilot ash was limited, an attempt to essentially solve the problem and to find an application object which is not related to the freeze- . It is meaningful that industrial recycling of Liquefied Ash has been made possible.

Furthermore, the economical efficiency of the binder / concrete composition is remarkably improved by using an inorganic binder, particularly a liquefied ash.

On the other hand, even if the effects are not explicitly mentioned here, the effect described in the following specification, which is expected by the technical features of the present invention, and its potential effects are treated as described in the specification of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a reaction scheme of a geopolymer of an inorganic binder and an alkali activator.
2 is a schematic view for explaining a geopolymer network.
3 is a view showing the structure of vinyl acetate ethylene.
FIG. 4 is a table showing the mixing ratio used in the experiment of the concrete composition according to the present invention, and the table of FIG. 5 shows the experimental results.
The accompanying drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may obscure the subject matter of the present invention.

The present invention relates to a hybrid polymer binder composition, a concrete composition in which the binder composition and aggregate are mixed, and a concrete structure (sewer pipe, conduit pipe, repair channel) using the concrete composition as a main material.

Since the binder polymer according to the present invention is mixed with an inorganic polymer binder and an organic polymer, the hybrid polymer binder composition is referred to as a hybrid polymer binder composition in the present invention.

The hybrid polymer binder composition (hereinafter, referred to as a 'binder composition') is mixed with an inorganic binder, an alkali activator, an organic polymer and a surfactant. It does not include cement, a binder widely used in construction and civil engineering. That is, the binder composition may partially contain cement according to the embodiment, but in this case, the cement is not a main material but contains only a small amount at the additive level.

In the present invention, the inorganic binder and the alkali activator form a geopolymer. The inorganic binder may be composed of at least one of fly ash, slag, and meta kaolin, and at least one of them may be mixed with a natural pozzolanic material. According to the embodiment, the inorganic binder may be prepared using only the natural pozzolanic material containing the aluminosilicate mineral as a main component. (NaAlSi ₃ O ₈ ), calcium aluminosilicate mineral (CaAl ₂ Si ₂ O ₈ ), or sodium calcium aluminosilicate mineral (Na _{0 .7 - 0.5} Ca _{0 .3} ) such as pyroxene _{- 0.5} Al _{1 .3 - 1.5} Si _{2 .7 - 2.5} O ₈ ) may be used. In the present invention, the content of CaO in the inorganic binder is preferably 20% or more.

Inorganic binders scheme of Figure 1 (1), having a hydroxyl group of alkali activator, for example, NaOH, Ca (OH) ₂ and sodium silicate is cured by reaction (Na ₂ SiO ₃₎ and as shown in (2) thereby to form the geo-polymer .

After the introduction of the geopolymer reaction by Davidovits in France in 1972, the study of the chemical structure of the geopolymer has been steadily carried out. According to the current mainstream view, the geopolymer has alternating oxygen atoms in the SiO ₄ and AlO ₄ tetrahedrons Network structure (see FIG. 2). That is, Al is substituted for Si in the continuous SiO ₄ tetrahedral structure. And Si has a tetravalent charge, while Al has a trivalent charge, forming a structure in which monovalent cations such as sodium (N) and potassium (K) are additionally bonded.

In particular, in the present invention, rejected ash can be utilized as an inorganic binder. There are two types of coal ash generated from coal-fired power plants: fly ash, which has a small specific gravity, and bottom ash, which has a large specific gravity. However, when dividing the ash, which is an industrial by-product, from the viewpoint of recycling, the important point is the content of unbeurned carbon. When the unburned carbon content is less than 5%, it is widely used as concrete material, but when the unburned carbon content is 5% or more, the entire amount is buried. . The ash that is disposed of is called a liquefied ash. Conventionally, liquefied ash has been treated by ocean dumping method. Currently, it is banned due to marine dumping, but it is difficult to dispose of it because of lack of landfill.

Unlike bottom ash, there are two main reasons why liquefied ash, which is a fine powder, is not used as a civil engineering material. In the case of concrete, the internal air volume should be maintained at 3 to 7%. It is necessary to buffer the freezing and thawing phenomenon in winter. Therefore, AE water reducing agent is added to concrete as an admixture to maintain air volume. However, when used as a concrete material, the unburned carbon content in the concrete adsorbs the AE water reducing agent, resulting in a significant decrease in the air content in the concrete. This is the main reason why we can not use liquefied ash as main material of concrete. Another reason is that the liquefied ash is composed of coarse aggregate, which is less reactive and less active than fly ash.

According to the present invention, a method of using a liquefied ash having an unburned carbon content of 5% or more as an inorganic binder is proposed.

The problem of ensuring air quality, the first weakness of Liquidated Ash, is related to freezing and thawing. However, since sewage pipes, conduits, and the like, which are the main applications of the present invention, are buried in the basement, freezing does not occur because the temperature change is not large even in winter. That is, the present invention solves the first weakness by specializing the application object. This is one of the most suitable applications in consideration of the characteristics of the liquefied ash, which is significant in terms of recycling byproducts. Also, in the case of a concrete structure exposed to the atmospheric state such as the open channel, the content of the AE water reducing agent is added by 0.1 to 2% or more based on 100 parts by weight of the inorganic binder so that the influence of the decrease in air amount by adsorption is minimized. However, the content of AE water reducing agent and AEA can be controlled according to the content of unburned carbon.

In order to overcome the second weakness, that is, the reactivity of the prepared ash, it is necessary to re-classify the purified ash in accordance with the grain size or pulverize the crude ash. The powdery ash of the prepared ash may be formed at a rate of 2,000 cm < ² > / g or more. Or so-called " mechanochemical " effects. That is, when the unburned carbon powder is put into the ball mill and the pressure is applied, the surface is modified to improve the reactivity.

As described above, the present invention has great significance in terms of suggesting a solution to overcome the disadvantages and weaknesses of the conventional ash that is not utilized at all as civil engineering and building materials. This is directly related to the problem of economic efficiency. The liquefied ash was disposed of at a cost, but by recycling it, it became possible to economically supply the concrete composition. Of course, fly ash and slag are economical compared to cement, but they can not be compared to the liquefied ash.

In the present invention, an admixture is added to improve the physical properties and workability of the binder composition and the concrete composition. As the admixture, any one of lignosulfate, naphthalene sulfonate condensate, melanin sulfone salt condensate and polycarboxylate may be used singly or in combination. Hydration can be delayed by using sodium gluconate, citric acid, tartaric acid, boric acid, H ₃ PO ₃ , H ₂ PO ₄ , and the like. They are particularly effective when using the liquefied ash as an inorganic binder.

That is, although the geopolymer using the inorganic binder shows a good performance in chemical resistance compared with the cement, the mechanical properties such as low brittleness and low bending strength are not enough to be used for sewage piping under the corrosive environment by the hydrogen bacteria inside the sewer pipe There is a weak point that it is easily broken by external impact. To compensate for this, it is necessary to improve chemical resistance and mechanical strength by mixing with an organic polymer.

In the present invention, the above-mentioned weakness is overcome by using an organic polymer. As the organic polymer, a polymer emulsion alone or a polymer modifier mixed with a polymer emulsion and a surfactant is used. The organic polymer having a transition temperature (Tg) in the range of -30 to 60 占 폚 can improve the elasticity and impact resistance of concrete during winter or summer, thereby reducing the generation of cracks.

In the present invention, the above-mentioned weakness is overcome by using an organic polymer. As the organic polymer, a polymer emulsion alone or a polymer modifier mixed with a polymer emulsion and a surfactant is used.

It is characterized by the use of vinyl acetate-ethylene (VAE; Vinyl Acetate-Ethylene). Referring to the structure of vinyl acetate-ethylene of FIG. 3, vinyl acetate-ethylene consists of a copolymer of vinyl acetate and ethylene. Vinyl acetate is polymerized at a ratio of 60 to 95%, and ethylene at a rate of 5 to 40%. VAE is used in some powder form, but it is generally used in liquid form. VAE is highly viscous and used in glass and plastic products to increase safety and durability.

The present invention also improves the flexural toughness or flexural strength of concrete by using VAE. Also, when VAE is used in concrete, it has an advantage of increasing water resistance and penetration resistance against chlorine ions, and thus increasing chemical resistance.

The material that should not be confused with vinyl acetate-ethylene is ethylene vinyl acetate (EVA; Ethylene Vinyl Acetate). EVA is mixed with 10 to 40% of vinyl acetate and 60 to 90% dml of ethylene. VAE and EVA have different properties and are treated as different materials because the materials participating in copolymerization are the same but the content ratio is completely different. For example, EVA is dissolved and used in a mold for injection molding in a solid state, but VAE differs in that it is used in an emulsion form.

In the present invention, VAE may be used alone as the polymer emulsion, but it may be mixed with a polymer such as styrene butadiene rubber or acrylic emulsion. In one embodiment of the present invention, even when styrene-butadiene rubber or acrylic polymer is mixed, the content of VAE is used in excess of 50% in the entire polymer emulsion. For example, in the entire polymer emulsion, VAE 50.1-99.9 wt%, styrene-butadiene rubber and acrylic polymer, or a mixture of styrene-butadiene rubber and acrylic polymer are mixed in a ratio of 0.1-49.1 wt%.

An important factor in the use as a modifier is the compounding ratio. Even if the same materials are mixed, the physical properties of the concrete are very different depending on the mixing ratio. In the present invention, the polymer emulsion is blended in an amount of 1 to 20% by weight based on 100 parts by weight of the inorganic binder. Such blend ratio is obtained through a number of experiments by the researchers of the present invention. If the blend ratio of the polymer emulsion is less than the above-mentioned range, the bending strength, crack resistance, flame retardancy and the like are not formed optimally for underground materials such as sewage pipes I do not. In addition, if the compounding ratio of the polymer emulsion exceeds the above-mentioned range, not only the economical efficiency is lowered but also the fluidity of the concrete is drastically lowered, resulting in a problem in workability.

On the other hand, when a polymer is included, the viscosity rises sharply and the binder can be agglomerated. In the present invention, a surfactant can be used to solve this problem. The polycarboxylic acid-based surfactant for preventing aggregation may be a copolymer of polyethylene glycol mono (meth) allyl ether and maleic anhydride, a copolymer of a polyalkylene glycol mono (meth) acrylate and a polyalkylene glycol mono (meth) (Meth) acrylic acid copolymer, a methacrylic acid ester having a sulfonic acid group, a (meth) acrylic acid copolymer, and a polyglycerin (meth) acrylic acid ester copolymer.

The water-dispersible urethane surfactant can be added to the polymer emulsion together with the polycarboxylic acid surfactant or alone. As the water-dispersed urethane surfactant, a modified water-dispersed polyurethane copolymer can be used.

In the present invention, the above polycarboxylic acid type and / or urethane type surfactant may be mixed with a nonionic surfactant for preventing aggregation of binders. The nonionic surfactant for preventing aggregation may be at least one selected from the group consisting of fatty acid diethanolamine compounds, amine oxides, nonylphenol ethylene oxide adducts, sorbitan esterified compounds, alkylpolyglycosides, fatty acid ethylene oxide adducts, polyethylene oxide, polypropylene oxide, Propylene copolymer, higher fatty acid (C12 to C22) diethanolamine compound, higher fatty acid (C12 to C22) ethylene oxide (EO) adduct (EO is 1 to 50), alkyl (C4 to C20) amine oxide, alkyl C4 to C20) phenol ethylene oxide adducts (EO is 1 to 50), sorbitan esterified compounds and ethylene oxide adducts (EO is 1 to 50), alkyl (C1 to C20) polychloric acid (molecular weight 100 (100 to 100,000), polyethylene oxide (100 to 100,000), polyethylene oxide (EPO) and polypropylene oxide (EPO) coalescence( Jaryang 100 ~ 100,000), and at least any one or two or more mixture of polyethyleneimine (molecular weight of 100 ~ 100,000), polyglycerol (molecular weight of 100 ~ 100,000).

When a polymer modifier mixed with a polymer emulsion having the above composition and a surfactant is used, the solid content of the polymer (VAE, SBR, Acryl) is uniformly dispersed in the concrete to form a polymer film, thereby improving the flexural toughness of the concrete , The diffusion of chlorine ions is largely prevented, and the resistance against shock and vibration is particularly enhanced.

In the present invention, the mixing ratio of the above materials was developed. That is, 20 to 80 parts by weight of the alkaline activator and 1 to 20 parts by weight of the organic polymer are mixed with 100 parts by weight of the inorganic binder and 100 parts by weight of the inorganic binder. And the admixture is mixed at a level of 0.05 to 3 parts by weight based on 100 parts by weight of the inorganic binder. Particularly, when using the reclaimed ash as an inorganic binder, the AE-based and AE-added AE water reducing agent and the AE high-performance water reducing agent can be used in a range of 0.1 to 3% based on 100 parts by weight of the liquefied ash. And AEA (air entraining agent) may contain 0.01 to 10% or more.

As described above, in the present invention, an inorganic polymer binder and an organic polymer were used. The problem of complementing the chemical resistance and mechanical properties, which was a problem in sewage pipe construction using conventional cement, was solved by using a hybrid polymer composed of an inorganic polymer and an organic polymer as a binder. In addition, the use of an inorganic binder, especially a liquefied ash, has dramatically improved the economical efficiency of the binder / concrete composition.

The present invention extends to a concrete composition based on a hybrid polymeric binder composition. The concrete composition is a mixture of the aggregate and the hybrid polymer binder composition. The aggregate may contain fine aggregate alone or fine aggregate and coarse aggregate. The aggregate is blended in the range of 100 to 300 parts by weight with respect to the binder composition to form a concrete composition.

The inventors of the present invention confirmed the performance of the concrete composition according to the present invention through experiments.

The table in FIG. 4 shows the mixing ratio used in the experiment of the concrete composition according to the present invention, and the table in FIG. 5 shows the experimental results.

The researchers fabricated a concrete specimen using the mixing ratio shown in FIG. 4, and measured the compressive strength, bending strength, tensile strength and chemical resistance of the specimen (unit: MPa). In Comparative Example 1, general cement was used. In Comparative Example 2, an inorganic binder was used, but an organic hybrid polymer was not used. The examples to which the present invention was applied used both fly ash and organic polymer

5, the compressive strengths of the comparative examples using cement and the examples according to the present invention were similar at 7 and 28 days age. That is, when cement is used, it is most advantageous that the compressive strength is high. In the present invention, the compressive strength is measured to be higher than that of cement while adopting cement. However, in Comparative Example 2 in which the organic polymer was not used, the compression strength was lowered

In addition, in the case of chemical resistance, it was confirmed that the hybrid polymer was superior to Comparative Example 1 using cement and Comparative Example 2 using only a geopolymer.

The present invention provides a concrete structure using a concrete composition having the above composition as a main material. The most typical concrete structures are characterized by being buried underground as sewage pipes and conduits. When buried in the basement, since the homogeneity of the temperature is maintained within a certain range, the freezing and thawing action does not occur, which is advantageous in that it can be used as an inorganic binder without any pretreatment for improving the reactivity of the reactor ash. The present invention also provides a concrete structure exposed to the outside air such as a repair channel. For structures exposed to the open air environment, it is possible to use the purified ash and the AE water reducing agent together or an inorganic binder having a low unburned carbon content.

Another advantage of the concrete composition according to the present invention in making sewage pipes, conduits and the like is related to the polymer emulsion. In general, polymer emulsions are often used to package facets. It is aimed at ensuring the strength of the salt. In case of pavement pavement, the curing time of the concrete composition is very important because it is done by the field construction method. Addition of polymer shortens the curing time, so it is necessary to add a hydration retarder or an anti-aggregation agent and keep the processing time precisely. However, when a polymer binder is used for a sewer pipe or a conduit pipe as in the present invention, it is very advantageous because it is not limited by the curing time because the work is carried out in a factory.

The scope of protection of the present invention is not limited to the description and the expression of the embodiments explicitly described in the foregoing. It is again to be understood that the present invention is not limited by the modifications or substitutions that are obvious to those skilled in the art.

Claims (14)

An inorganic binder forming a geopolymer;
An alkali activator which causes a geopolymer reaction of the inorganic binder; And
An organic polymer for improving the flexural strength of the geopolymer; And
A surfactant for improving the workability of the inorganic polymer,
The inorganic binder includes a rejected ash containing 5% or more of unburned carbon content and a powder degree of 2,000 cm ² / g or more. The airbag includes an air entraining agent AEA) in an amount of 0.01 to 10% by weight relative to the inorganic binder,
The organic polymer includes vinyl acetate ethylene (Vinyl Acetate-Ethylene) as the water dispersion polymer,
Wherein the inorganic binder is mixed with 100 parts by weight of the inorganic binder and 20 to 80 parts by weight of the alkali activator and 1 to 20 parts by weight of the organic polymer with respect to 100 parts by weight of the inorganic binder. The method according to claim 1,
Wherein the inorganic binder comprises at least one of fly ash, slag and meta kaolin, fine powder obtained by pulverizing bottom ash, silica fume, and CA (OH) ₂ . delete delete delete delete delete The method according to claim 1,
Wherein the alkali activator comprises sodium silicate and sodium hydroxide. 9. The method of claim 8,
The molar ratio of Na ₂ O to SiO ₂ in the inorganic binder and an alkaline activator is mixed state (Na ₂ O / SiO ₂₎ is a hybrid polymeric binder composition, characterized in that 0.5 to 3.0. delete 1. A concrete composition comprising an aggregate and a binder composition for interconnecting the aggregate,
Wherein the binder composition is the hybrid polymer binder composition according to claim 1. 12. The method of claim 11,
Wherein the aggregate is blended in an amount of 100 to 300 parts by weight based on 100 parts by weight of the inorganic binder. The concrete structure according to claim 11, wherein the concrete structure is made of the concrete composition according to claim 11 so that chemical resistance and bending strength are improved. 14. The method of claim 13,
Wherein the concrete structure is any one of a sewer pipe, a water pipe, and a conduit pipe.

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