KR102001032B1 - Durability improvement method for water treatment structure using eco-friendly composition - Google Patents

Abstract

The present invention relates to a durability increasing method for repairing and reinforcing a water treatment structure and increasing waterproof and anticorrosive performance by using an environmentally-friendly composition. According to the present invention, the durability increasing method comprises: a step (S10) of treating a surface of an object to be repaired and reinforced of a structure; a step (S20) of restoring the cross section of the object to be repaired and reinforced of a structure by a polymer mortar composition including cement, ethylene vinyl acetate (EVA)-based polymer, phenoxy resin, calcium sulfonate aluminate, a shrinkage prevention agent, a defoaming agent, a silicone water repellent, and an antirust agent; and a step (S30) of finishing the cross section of the object to be repaired and reinforced of a structure by using a finishing composition including resin, a curing agent, pigment with an average particle size of 1 to 40 μm, metal oxide nanoparticles with an average particle size of 40 to 250 μm, a dispersing agent, a thickener, non-silicone hybrid copolymer, a filler, and an anti-sagging agent.

Description

[0001] The present invention relates to a durability improvement method for water treatment structure using eco-friendly composition,

The present invention relates to an eco-friendly method for improving the durability of a structure. More specifically, the present invention relates to a method for repairing a cross-section of a water treatment structure, It is applied to structures exposed to severe corrosive environment such as direct flooding or exposure to various chemicals, and is widely applied regardless of the type and size of the structure such as waterproofing and function development, thereby improving the durability of the structure, And thus is environmentally friendly.

In general, concrete structures are structurally problematic due to deterioration over time despite high durability. Although these deterioration phenomena appear in various ways, cracks occur due to the drying shrinkage and thermal contraction of the concrete itself, and the neutralization of the concrete is promoted at cracks of such a structure, and a deterioration phenomenon occurs in the concrete portion in a complex manner There is a problem that the surface of the structure shows peeling and peeling phenomenon.

Therefore, maintenance and reinforcement are inevitable in these concrete structures due to structural problems such as deterioration and changes in external load with time, and various mortars have been proposed as repair / reinforcement mortars.

Korean Patent No. 635464 discloses that 10 to 39.5% by weight of cement; 30 to 35 wt% of fine aggregate; 10 to 15% by weight of fly ash; Light beads having a specific gravity of 0.8 to 1 and a particle size of 60 to 150 占 퐉; 3-5 wt% CSA expanding material; 2 to 5% by weight of silica fume; 0.2 to 0.5% by weight of a fluidizing agent; 10 to 19.5% by weight of water; And PVA reinforcing fibers having a length of 8 to 12 mm, each of 1 to 3% of the total volume.

However, although the above-mentioned technology solves the cracking problem due to the stiffening by reinforcing fibers, resistance to various deteriorating factors such as acid resistance and flame retardancy may be required depending on the type of the structure, which may limit its application.

Korean Patent No. 635464

In order to solve the above problems, the present invention provides a structure durability enhancement method that exhibits resistance to various deteriorating factors such as corrosion resistance, acid resistance, and salt resistance.

The durability enhancement method (hereinafter referred to as "the method of the present invention") for repairing, reinforcing and waterproofing / improving the performance of a water treatment structure using the environmentally friendly composition of the present invention for solving the above- Treating the surface with respect to the object (SlO); (S20) restoring a cross section of a structure to be repaired or reinforced by a polymer mortar composition comprising cement, an EVA polymer, a phenoxy resin, calcium sulphoaluminate, a shrinkage inhibitor, a defoamer, a silicone water repellent, and a rust inhibitor; A finishing composition comprising a resin, a curing agent, a pigment having an average particle diameter of 1 to 40 μm, a metal nanoparticle oxide having an average particle diameter of 40 to 250 nm, a dispersant, a thickener, a non-silicone based copolymer, a filler, (S30) of finishing the cross section of the object to be repaired and reinforced by the structure.

As one example, the filler includes graphite and a butyl rubber having a carbon component.

As an example, in step S10, chipping and high-pressure cleaning of the object to be repaired / reinforced (S11); (S12) applying a pretreatment composition containing Teflon resin, calcium nitrite, a viscous agent and a viscous stabilizer to the object to be repaired and reinforced by the structure.

In one example, the viscosifier is a mixture of beta carotene and triisooctyl phosphate.

The method of the present invention has the following advantages.

First, there is an advantage in that the durability of the structure is improved by performing maintenance and reinforcement to improve physical properties such as waterproofing and rustproofing property in degraded and damaged parts of various structures.

Second, since the present invention does not include lead, cadmium, mercury, arsenic, antimony and their compounds and hexavalent chromium compounds in the coating, it has an advantage of being environmentally friendly.

1 is a block diagram showing a method of the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples. The embodiments according to the present invention can be modified into various other forms, and thus the scope of the present invention is not limited to the embodiments described below.

As shown in FIG. 1, the method of the present invention includes the steps of: (S10) treating a surface to be treated or reinforced by a structure; (S20) restoring a cross section of a structure to be repaired or reinforced by a polymer mortar composition comprising cement, an EVA polymer, a phenoxy resin, calcium sulphoaluminate, a shrinkage inhibitor, a defoamer, a silicone water repellent, and a rust inhibitor; A finishing composition comprising a resin, a curing agent, a pigment having an average particle diameter of 1 to 40 μm, a metal nanoparticle oxide having an average particle diameter of 40 to 250 nm, a dispersant, a thickener, a non-silicone based copolymer, a filler, (S30) of finishing the cross section of the object to be repaired and reinforced by the structure.

First, the method of the present invention has a step (S10) of treating a surface to be treated and reinforced by a structure. Here, the term "structure" may be a concrete structure or the like.

In step S10, the surface of the structure is treated to remove impurities to be treated or reinforced by chipping and high-pressure washing.

Next, the step of restoring the section to the object to be repaired / reinforced (S20) is performed. In the structure, the section is restored to the object to be repaired / reinforced, and the base is adjusted.

In step S20 of the present invention, an example of recovering a cross section by a polymer mortar composition including cement, EVA polymer, phenoxy resin, calcium sulfur aluminate, shrinkage inhibitor, defoamer, silicone water repellent, and rust inhibitor is suggested.

Preferably, the polymer mortar composition comprises 5 to 20 parts by weight of an EVA polymer, 5 to 10 parts by weight of a phenoxy resin, 3 to 8 parts by weight of calcium sulfurized aluminate, 0.5 to 2 parts by weight of a shrinkage inhibitor, 0.5 to 2 parts by weight of a defoaming agent, 0.5 to 2 parts by weight of a silicone water repellent, and 0.5 to 2 parts by weight of an antirust agent.

In the present invention, the cement may include a quick-curing cement, and the cement may be partially replaced by using fly ash or blast furnace slag or the like as a mixing material in order to exhibit rapid curing.

The quick-setting cement is preferably one of a calcium sulfoaluminate-based (CSA-based), alumina cement-based, calcium aluminate-based (C12A7-based) or a mixture thereof for exhibiting ultra fastness.

The EVA (ethylene vinyl acetate) polymer is intended to exhibit the cohesive force and waterproof property of the paste.

The calcium sulfuric aluminate is used as a swelling agent for controlling cracks such as temperature cracks that may occur in a curing process and the like. In the case of the shrinkage preventing agent, the shrinkage of the paste such as drying shrinkage is controlled to control cracks.

The rust inhibitor is one of calcium nitrate, benzoate, orthophosphate and silicate or a mixture thereof.

In the prior art, silica fume is added for strength reinforcement and the like, but when silica fume is added, the strength is reinforced but the workability is lowered. In the present invention, a water-soluble phenoxy resin is added.

The water-soluble phenoxy resin is preferably a water-soluble or water-dispersible, water-stabilized polymer having a number average molecular weight of about 20,000 to 60,000. The above-mentioned phenoxy resin having a molecular weight can be obtained by increasing the molecular weight to the above range using an epoxy resin and bisphenol A.

To obtain a phenoxy resin, the obtained phenoxy resin was neutralized with a tertiary amine having a hydroxyl group to give an acid neutralization group, neutralized by adding phosphoric acid as a neutralizing agent for the water, Can be used by preparing a water-soluble phenoxy resin solution.

Such a water-soluble phenoxy resin is added as a water-soluble polymer, and a coating function is imparted through a polymer emulsion of an aqueous component.

That is, the water-soluble phenoxy resin is dispersed in water to form a polymer film by evaporation of water by coating or the like, thereby suppressing moisture evaporation from the particle surface. That is, water evaporation is prevented by such a water-soluble phenoxy resin, so that cracks due to capillary phenomenon can be controlled. Also, the problem of lowering the fluidity due to evaporation of water is also solved.

According to the present invention, the step (S11) includes chipping and cleaning the object to be repaired / reinforced by the structure at step S10. (S12) applying a pretreatment composition containing Teflon resin, calcium nitrite, a viscous agent and a viscous stabilizer to the object to be repaired and reinforced by the structure.

Preferably, the pretreatment composition comprises 1 to 5 parts by weight of calcium nitrite, 1 to 5 parts by weight of a viscous agent, and 1 to 3 parts by weight of a viscous stabilizer based on 100 parts by weight of the Teflon resin.

The pretreatment material composition is applied to the exposed section and the reinforcing bar after the chipping and deformation of the reinforcing bar are removed in the previous step (S11), thereby improving the adhesion between the polymer mortar for the restoration of the section, To prevent the corrosion point, moisture and the like which may remain by the polymer mortar from being directly exposed to the deterioration of the restoration section.

The preprocessing composition is mainly composed of Teflon resin. In general, epoxy resin or the like is used as a main component of the primer to show strong alkalinity of the cross section of the concrete. Also, the polymer mortar for restoration shows strong alkalinity, , The existing primer has a problem of deteriorating the function as a primer in a strong alkaline environment. In the case of Teflon resin, the viscosity is maintained even under a strong alkaline environment, and the adhesion between the object to be treated and the polymer and the mortar Is maintained.

The above-mentioned calcium nitrite is intended to prevent the corrosion from expanding due to the fine rust remaining in the reinforcing bar despite the cross-sectional arrangement.

However, when calcium nitrite alone is added, the corrosion resistance to the fine rust remaining in the reinforcing bar can be improved. However, there is a problem that the physical properties may be lowered due to the excessive addition of calcium nitrite. And there exist moisture in the micropores. In such a case, the water present in the reinforcing pores may eventually cause corrosion of the reinforcing bars.

The limestone powder may be further added to the pretreatment composition of the present invention.

The reason for adding the limestone powder is that the limestone powder absorbs the water present in the reinforcing bar cavity to improve the rust prevention property in the reinforcing bar and at the same time the limestone powder in which the moisture is absorbed expands and cracks due to shrinkage during the curing process of the pretreatment material .

The limestone powder is calcined at 1000 to 1300 ° C. The calcined limestone is used to hydrate the calcium oxide to cause calcium hydroxide to be formed, thereby expanding the paste during mixing. When the limestone powder is mixed with moisture contained in the pores of the reinforcing bar It is known that calcium hydroxide is absorbed and hydrated and calcium hydroxide is formed. This expansion is known to cause apparent expansion of volume while leaving pores. The expansion is known to be due to the expansion of two stages. First, calcium hydroxide It is known that it first grows at the time of generation and continues to grow into a hexagonal plate-like crystal of great anisotropy even after it is completely terminated.

Therefore, the limestone powder absorbs the water present in the pores of the reinforcing bar and expands itself, and this expansion expands the paste to improve the crack resistance.

The viscosifying agent is for enhancing the adherence, and the viscous agent is not limited in its kind.

However, if only the viscous agent is used, there is a problem that when the polymer mortar is applied, the viscosity of the polymer mortar tends to decrease due to the heat of the polymer mortar. As a result, the function of improving the adhesive force as a function of the pretreatment material is degraded. .

Preferably, the present invention provides an example wherein the viscous stabilizer comprises a mixture of beta carotene and triisooctyl phosphate.

The beta-carotene is advantageous in that it has excellent water-holding ability and does not cause a change in viscosity over time. However, in the case of a curing process, especially in a hot summer, the viscosity may decrease due to a rise in temperature during the curing process.

Accordingly, the present invention provides an example in which a mixture in which triisooctyl phosphate is further added in addition to beta-carotene as a viscous stabilizer.

That is, triisooctyl phosphate is added in addition to beta carotene as a viscous stabilizer. Triisooctyl phosphate is excellent in heat resistance so that the gel network is not destroyed even when the temperature rises. As a result, the temperature rise of beta carotene So that the problem of the viscosity decrease according to the present invention can be controlled.

Preferably, beta carotene and triisooctyl phosphate are mixed in a ratio of (3 to 7): (4 to 6) by weight.

After step S10 and step S20 described above, that is, coating the finish composition on the surface of the structure having the section resurfaced (step S30).

In particular, the finishing composition comprises a resin, a curing agent, a pigment having an average particle size of 1 to 40 μm, a metal nanoparticle oxide having an average particle size of 40 to 250 nm, a dispersant, a thickener, a non-silicone based copolymer, a filler, .

The finishing composition preferably contains 10 to 20 parts by weight of a curing agent per 100 parts by weight of the resin, 30 to 80 parts by weight of pigment having an average particle diameter of 1 to 40 탆, metal nanoparticle oxide having an average particle diameter of 40 to 250 nm, 2 to 5 parts by weight of a dispersing agent, 2 to 5 parts by weight of a thickening agent, 2 to 5 parts by weight of a non-silicon based copolymer, 5 to 10 parts by weight of a filler and 2 to 5 parts by weight of a flow inhibitor.

The above-mentioned finishing composition exhibits an effect that a pigment having an average particle diameter of 1 to 40 μm and a metal nanoparticle having a diameter of 40 to 250 nm are filled with voids of large particles due to a difference in particle size and density, and thus the resin and the pigment and metal nanoparticles have a dense square lattice By forming a passive coating in the form of a structure (cube structure, called "nanocube"), the functions such as abrasion resistance, salt resistance, corrosion resistance, and adhesion are improved to protect the surface of the substrate and prevent penetration of harmful factors. So that it can be increased.

It is appropriate that the pigment has an average particle diameter of 1 to 40 탆 and the metal nano-particle oxide has a particle diameter of 40 to 250 nm because the pigment has the same basic arrangement for each particle, The more the grain boundary per unit area is present, the stronger the mechanical properties are, the better the frame structure of the flake structure is, and the frame of the flake structure is filled with the fine metal nanoparticle oxide, So that the structure is formed.

Silicone Modified Epoxy Resin, Silicone Modified Acrylic Copolymer, etc. may be used as the resin.

The curing agent may be a polyamide room temperature curing type hardening agent or a polyisocyanate curing agent.

It is appropriate that the pigment does not contain lead, cadmium, mercury, arsenic, antimony and compounds thereof and hexavalent chromium compound, and is one or a mixture of titanium dioxide, talc, silicon dioxide, aluminum powder, ceramics.

The metal nanoparticle oxide may be at least one selected from the group consisting of titanium dioxide, silicon dioxide, manganese, magnesium, aluminum, zinc oxide, indium tin oxide, magnesium silicate, magnesium oxide, antimony tin oxide, kaolin, Niobium pentoxide, niobium pentoxide, vanadium pentoxide, and tungsten bronze.

As the dispersing agent, it is preferable to use a surfactant (Unsaturated Polymide acid Ester Salts).

It is also preferable to use an organic clay as the thickening agent.

It is also preferable that a non-silicon based copolymer, an anti-flow agent and an anti-settling agent are blended.

Also, in this embodiment, 20 to 50 parts by weight of a solvent is further included in 100 parts by weight of the resin. Preferably, the solvent is a mixture of one or more of an aromatic solvent (toluene, xylene), a ketone solvent, and an alcohol solvent, preferably a volatile organic compound content of 300 g / L or less, a volatile aromatic hydrocarbon content of 25 wt% By weight or less, and benzene in an amount of 0.1% by weight or less.

It is appropriate to limit the pigment to have an average particle diameter of 1 to 40 mu m. The reason for this limitation is that when the particle size is smaller than the above range, the function is insufficient as a sufficient frame. If the particle size exceeds the above range, the specific gravity becomes too large, and the dispersibility is lowered, resulting in non-uniform physical properties.

In addition, it is appropriate that the metal nanoparticle oxide has an average particle diameter of 40 to 250 nm. When the metal nano-particle oxide is less than 40 nm, the distribution of the average particle size is too low to be expensive, which is not economical. When the particle size exceeds 250 nm, the average particle size distribution is large, It is impossible to fill properly and it will hinder the closed structure.

On the other hand, the filler may include graphite and butyl rubber having a carbon component. This embodiment is particularly applicable when the environmentally friendly coating composition is used as the above-mentioned top layer or finish layer.

The graphite having the carbon component is for reinforcing strength and improves impact resistance against external impact. Graphite having a carbon component as a conductor is added to control the generation of static electricity so that foreign matter is deposited on the surface by static electricity . In other words, in case of accumulation of foreign matter, it is possible to cause corrosion on the surface.

The butyl rubber is a rubber obtained by ion-polymerizing isobutylene and a small amount of isoprene in a liquid state at a low temperature, and isobutylene having a purity of 99% or more is added to the graphite having a purity of at least 1.5% 4.5% of isoprene mixture and pure methyl chloride were added, and anhydrous aluminum chloride was added as a catalyst. The mixture was polymerized at a low temperature of -100 ° C in a polymerization reactor. The unsaturated polyester resin was polymerized with halogenated butyl rubber Polyisobutylene, and the like. Such butyl rubber absorbs impacts well and has elasticity at temperatures as low as -50 ° C, especially since the elastomer does not crystallize even at low temperatures.

The reason for adding the butyl rubber is not only to strengthen the impact resistance but also to suppress the impact on the stretch due to the property of the material which does not lose its elasticity even at low temperatures, So that the cold resistance can be improved.

That is, if the paste is repeatedly frozen and thawed at a low temperature, cracks may be generated in the paste due to repeated stretching and shrinkage. The butyl rubber can maintain elasticity even at low temperatures and can compensate for such expansion and contraction. It is possible to control the above.

As shown in the following Table 1, it can be seen that the content of the volatile organic compound is low and benzene, lead, cadmium, mercury and hexavalent chromium are not detected, and as a result, it is proved that the coating composition is environmentally friendly have.

Test Items unit Test result Test Methods VOCs Content (g / L) 40.8 KS M ISO 11890-2 VACs content(%) 4.13 ASTM D 3257 benzene Detection (mg / L) N.D (non-detection, below detection limit) ASTM D 3257 lead mg / kg N.D (non-detection, below detection limit) KS M ISO 3856-1 Cat mg / kg N.D (non-detection, below detection limit) KS M ISO 3856-1 Mercury mg / kg N.D (non-detection, below detection limit) KS M ISO 3856-1 Hexavalent chromium mg / kg N.D (non-detection, below detection limit) KS M ISO 3856-1

Test Items Exam conditions Test result Test Methods Acid resistance 50% sulfuric acid, 24h clear KSM ISO 2812-1: 2012 5% HCI, 168h clear KSM ISO 2812-1: 2012 Chemical resistance 5% citric acid, 24h clear KSM ISO 2812-1: 2012 2% sodium hypochlorite, 24h clear KSM ISO 2812-1: 2012 Water resistance Deionized water, 168h clear KSM ISO 2812-1: 2012 Oil resistance Diesel, 168h clear KSM ISO 2812-1: 2012 Abrasion resistance CS-17, 1000 g, 1000 times 79 mg ASTM D4060-10 Impact resistance 12.7 mm, 50 cm, 1000 g clear KSD 3520: 2008 Heat resistance 300 ± 5 ° C, 1h clear KSM 5000: 2009 Solvent resistance 98.5% Xylene, 8h clear KSM ISO 2812-1: 2012 Cold resistance -30 ± 2 ° C, 1h clear KSM 5000: 2009 Neutral salt spray test 10000h clear KSM 9502: 2009 Bond strength Pretreatment grade -A 7.0 N / mm < 2 & ASTM D4541-09e (*) Bond strength Pre-treatment grade-B 7.5 N / mm < 2 & ASTM D4541-09e (*) Bond strength Pretreatment grade -C 7.5 N / mm < 2 & ASTM D4541-09e (*)

Also, as shown in Table 2, it is seen that excellent results are obtained in terms of acid resistance, chemical resistance, water resistance, and adhesion strength. As mentioned above, the finishing composition has a pigment with an average particle diameter of 1 to 40 탆 and a pigment with an average particle diameter of 40 to 250 nm Of metal nanoparticles fill the pores of large particles by the difference in particle size and density, so that resin, pigment and metal nanoparticles form a dense square lattice structure (cube structure, referred to as "nanocube & It is believed that this is due to the formation of a film.

While the present invention has been described with reference to the particular embodiments and drawings, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Various modifications and changes may be made.

Claims (4)

A step (S10) of treating the surface of the object to be repaired / reinforced;
(S20) restoring a cross section of a structure to be repaired or reinforced by a polymer mortar composition comprising cement, an EVA polymer, a phenoxy resin, calcium sulphoaluminate, a shrinkage inhibitor, a defoamer, a silicone water repellent, and a rust inhibitor; And
A finishing composition comprising a resin, a curing agent, a pigment having an average particle diameter of 1 to 40 μm, a metal nanoparticle oxide having an average particle diameter of 40 to 250 nm, a dispersant, a thickener, a non-silicone based copolymer, a filler, (S30) of finishing a section of the structure to be subjected to maintenance and reinforcement,
Preferably,
Graphite and butyl rubber having a carbon component are contained so as to prevent the deposition of foreign matter by static electricity and to prevent cracking of the paste due to freezing and thawing by retraction and retention at a low temperature, · Reinforcement and waterproofing · Durability enhancement method to improve system performance.
delete The method according to claim 1,
In the step S10,
A step (S11) of chipping and high-pressure cleaning the object to be repaired / reinforced;
(S12) of applying a pretreatment composition containing Teflon resin, calcium nitrite, a viscous agent, and a viscous stabilizer to the object to be repaired / reinforced by the structure;
And a durability improving method for improving waterproofing and performance of a water treatment structure by using an environmentally friendly composition.
The method of claim 3,
Wherein the viscous stabilizer is a mixture of beta carotene and triisooctyl phosphate. The durability improving method for repairing, reinforcing, waterproofing, and improving the performance of a water treatment structure using an environmentally friendly composition.

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