JP2003221576A - Water absorption-preventing material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water absorption-preventing material capable of maintaining the water absorption-preventing properties over a long period. <P>SOLUTION: This water absorption-preventing material comprises (A) an alkylalkoxysilane and/or a condensate thereof, (B) at least one kind of an inorganic mineral, a water-soluble polymer and a water-absorbing resin, and (C) a polar solvent. Preferably, the water absorption-preventing material comprises (A) 60-95 wt.% alkylalkoxysilane and/or condensate thereof, (B) 0.01-20 wt.% at least one kind of the inorganic mineral, the water-soluble polymer and the water-absorbing resin, and (C) 4-30 wt.% polar solvent, and has 100-10,000 mPas viscosity at 25°C. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a water absorption preventive material. More specifically, it relates to a water absorption preventive material which is mainly applied to a porous civil engineering building material to prevent water absorption of the material for a long period of time and protects the material for a long period of time.

[0002]

2. Description of the Related Art It has been widely known that an alkylalkoxysilane or a condensate thereof is useful as a water absorption preventing material for porous civil engineering and construction materials. In general,
Organic solvent-type water absorption preventive materials obtained by diluting these alkylalkoxysilanes or condensates thereof with various organic solvents, and emulsion type water absorption preventive materials obtained by emulsifying the alkylalkoxysilanes or condensates thereof in water are used. However, when such an organic solvent-type or emulsion-type water-absorption preventing material is applied to a substrate, the alkylalkoxysilane or its condensate penetrates into the substrate and volatilizes out of the substrate. Since the total amount of the applied alkylalkoxysilane or its condensate cannot penetrate into the base material, there is a problem that a deep permeation layer of the alkylalkoxysilane or its condensate cannot be formed on the base material.

For this reason, it has been attempted to permeate the alkylalkoxysilane or its condensate deep inside the substrate by increasing the coating amount, but in the state where permeation and volatilization occur at the same time, a certain amount is obtained. It is difficult to penetrate the above-mentioned alkylalkoxysilane or its condensate deep inside the substrate. As a result, there is a drawback that a deep permeation layer of the alkylalkoxysilane or its condensate cannot be formed, and the water absorption preventing property of the substrate cannot be maintained for a long period of time.

[0004]

The object of the present invention is to provide an alkylalkoxysilane and / or
Alternatively, volatilization of the condensate is suppressed, and almost the entire amount of the condensate permeates into the base material, and a deep permeation layer of the alkylalkoxysilane and / or its condensate is formed on the surface layer of the base material.
It is to provide a water absorption preventing material capable of maintaining the water absorption preventing performance for a long period of time.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that at least an alkylalkoxysilane and / or a condensate thereof, an inorganic mineral, a water-soluble polymer and a water-absorbent resin. When a water absorption inhibitor composed of one type and a polar solvent is used, the alkylalkoxysilane and / or its condensate can be prevented from volatilizing, and almost the entire amount penetrates into the inside of the substrate, and the alkylalkoxysilane is present on the surface layer of the substrate. The present invention has been completed by finding that a deep permeation layer of a condensate thereof and / or a condensate thereof is formed and the water absorption preventing performance can be maintained for a long period of time.

That is, the present invention provides (A) an alkylalkoxysilane and / or a condensate thereof, (B) an inorganic mineral, at least one of a water-soluble polymer and a water-absorbent resin,
And (C) a water absorption preventing material comprising a polar solvent.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The water-absorption preventing material of the present invention comprises (A) an alkylalkoxysilane and / or a condensate thereof,
(B) an inorganic mineral, at least one of a water-soluble polymer and a water-absorbent resin, and (C) a polar solvent. Hereinafter, the above-mentioned (A), (B) and (C) constituting the water absorption preventing material of the present invention will be described.

(A) Alkylalkoxysilane and /
Or its condensate The alkylalkoxysilane used in the present invention is not particularly limited, but a compound represented by the following general formula (1) is preferably used.

[0009]

[Chemical 2]

In the formula, R ¹ represents an alkyl group having 1 to 20 carbon atoms and R ² represents an alkyl group having 1 to 4 carbon atoms. n is 1 or 2.

Examples of the alkyl group having 1 to 20 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group. Etc.

The alkyl group having 1 to 4 carbon atoms includes
Examples thereof include a methyl group, an ethyl group, a propyl group and a butyl group.

Specific examples of such alkylalkoxysilanes include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, butyltrimethoxysilane,
Butyltriethoxysilane, Pentyltrimethoxysilane, Pentyltriethoxysilane, Hexyltrimethoxysilane, Hexyltriethoxysilane, Heptyltrimethoxysilane, Heptyltriethoxysilane, Octyltrimethoxysilane, Octyltriethoxysilane,
Nonyltrimethoxysilane, nonyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, undecyltrimethoxysilane, undecyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, tridecyltrimethoxysilane, tridecyl Triethoxysilane, tetradecyltrimethoxysilane, tetradecyltriethoxysilane, pentadecyltrimethoxysilane, pentadecyltriethoxysilane, hexadecyltrimethoxysilane, hexamethyltriethoxysilane, heptadecyltrimethoxysilane, heptadecyltriethoxy Silane, octadecyltrimethoxysilane, octadecyltriethoxysilane, dimethyldimethoxysilane, octylmethyldimethoxysilane, octade Methyl dimethoxysilane and the like.

Among them, hexyltrimethoxysilane, hexyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane in which the alkyl group represented by R ¹ in the general formula (1) has 6 or more carbon atoms. Is preferably used. These alkylalkoxysilanes can also be used as a partial condensate or a mixture.

The proportion of the alkylalkoxysilane and / or its condensate is from 60 to 95 of the total weight of the water absorption inhibitor.
It is desirable that the content is wt%, preferably 70 to 93 wt%. If the proportion is less than 60% by weight, the effect of preventing water absorption of the substrate may not be obtained. On the other hand, if the proportion exceeds 95% by weight, the viscosity of the resulting water-absorption preventing material may be too high, and it may not be possible to uniformly apply it to the substrate.

(B) Inorganic Mineral, Water-Soluble Polymer, and Water-Absorbent Resin The inorganic mineral used in the present invention is not particularly limited, but includes montmorillonite, bentonite, beidellite, nontronite, saponite, hectorite, leuconite, and volcon. Examples thereof include scorate, permiculite, and kuromomo. Among them, montmorillonite or bentonite is preferably used.

The water-soluble polymer used in the present invention is not particularly limited, but hydroxyethyl cellulose, carboxymethyl cellulose, polyethylene oxide, sodium polyacrylate, methyl cellulose,
Examples thereof include polyvinyl alcohol, polyacrylamide, polyvinyl pyridine, polyethylene imine, guar gum, starch, gelatin and chitosan.

Among them, hydroxyethyl cellulose, carboxymethyl cellulose, polyethylene oxide,
Sodium polyacrylate is preferably used, and hydroxyethyl cellulose is more preferably used.

As the water-absorbent resin used in the present invention,
Although not particularly limited, polyalkylene oxide modified products,
Acrylate polymer cross-linked product, starch-acrylic acid salt graft copolymer cross-linked product, isobutylene-maleic anhydride copolymer, vinyl alcohol-acrylic acid salt copolymer cross-linked product, maleic anhydride grafted polyvinyl alcohol Crosslinked product, crosslinked product of acrylic acid-methacrylic acid copolymer, crosslinked product of saponified product of methyl acrylate-vinyl acetate copolymer, crosslinked product of saponified product of starch-ethyl acrylate graft copolymer, Examples include carboxymethyl cellulose crosslinked products and polyethylene oxide crosslinked products.

Among them, polyalkylene oxide modified products,
A cross-linked product of an acrylate polymer and a cross-linked product of a starch-acrylate graft copolymer are preferably used, and a cross-linked product of an acrylate polymer is more preferably used.

In the present invention, the inorganic mineral, the water-soluble polymer and the water absorbent resin may be used alone or in combination of two or more kinds. The combination method in this case is not particularly limited and is arbitrarily selected from the above.

The proportion of at least one of the inorganic mineral, water-soluble polymer and water-absorbent resin is 0.01 to 20% by weight, preferably 0.1 to 15% by weight, based on the total weight of the water-absorption preventing material.
Is desirable. If the proportion is less than 0.01% by weight, even if the resulting water absorption inhibitor is applied to the substrate, the alkylalkoxysilane or its condensate cannot volatilize and penetrate deeply into the substrate, There is a possibility that the water absorption preventing performance cannot be maintained for a long period of time. On the other hand, if the proportion exceeds 20% by weight, the viscosity of the resulting water-absorption preventing material may be too high, and it may not be possible to uniformly apply it to the substrate.

(C) Polar Solvent The polar solvent used in the present invention is not particularly limited, but alcohols such as methanol, ethanol and isopropyl alcohol; acetone, methyl ethyl ketone,
Examples thereof include ketones such as methyl isobutyl ketone, nitriles such as acetonitrile, and water. Among them, ethanol, isopropyl alcohol and water are preferably used.

In the present invention, the polar solvents may be used alone or in combination of two or more kinds.

It is desirable that the proportion of the polar solvent is 4 to 30% by weight, preferably 6 to 25% by weight based on the total weight of the water absorption inhibitor. If the proportion is less than 4% by weight, the viscosity of the resulting water-absorption preventing material may be too high, and it may not be possible to apply it uniformly to the substrate. If the proportion exceeds 30% by weight, the alkylalkoxysilane or its condensate cannot penetrate deeply into the base material even if it is applied to the base material, so that the water absorption preventing performance should be maintained for a long time. I can't.

The water-absorption preventing material of the present invention is, for example, at least one of (A) an alkylalkoxysilane or a condensate thereof, (B) an inorganic mineral, a water-soluble polymer or a water-absorbing resin.
Seeds and (C) polar solvent at room temperature with a homomixer,
It can be produced by stirring and mixing using a stirrer such as an ultra disperser or a high pressure homogenizer.

In the present invention, when only water is used as the polar solvent, it is preferable to stir and mix in the presence of an emulsifier.

As the emulsifier, any of nonionic emulsifiers, cationic emulsifiers and anionic emulsifiers can be used, and nonionic emulsifiers are preferably used. As a nonionic emulsifier,
For example, ether type nonionic emulsifiers such as polyoxyethylene lauryl ether; alkylphenol type nonionic emulsifiers such as polyoxyethylene nonylphenyl ether and polyoxyethylene octylphenol ether;
Ester type nonionic emulsifiers such as polyoxyethylene monooleate; sorbitan ester type nonionic emulsifiers such as sorbitan monolaurate; sorbitan ester ether type nonionic emulsifiers such as polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan monostearate Is mentioned. The above emulsifiers may be used alone or in combination of two or more.

The amount of the emulsifier used is 1 to 2 of the polar solvent.
It is desirable that the content is 0% by weight, preferably 5 to 15% by weight. If the emulsifier is used in an amount of less than 1% by weight, it may be difficult to uniformly mix it. Further, when the amount of the emulsifier used exceeds 20% by weight, there is no effect corresponding to the amount used and it is not economical.

The water absorption preventive material of the present invention has a viscosity at 25 ° C. of 100 to 10,000 mPa · s, preferably 200 to 3,000 mPa · s. If the viscosity is less than 100 mPa · s, there will be a problem with stability such as separation of the water absorption preventive material into two layers, and if the water absorption prevention material is applied to a vertical wall surface, the water absorption prevention material will drip down, resulting in a uniform coating. May not be possible. Also, the viscosity is 1000
If it exceeds 0 mPa · s, the fluidity of the water-absorption preventing material may be extremely reduced, and it may not be possible to coat with a roller, a brush, a spray or the like.

The viscosity in the present invention means a value measured using a B type viscometer (manufactured by Tokyo Keiki) under the conditions of a measuring temperature of 25 ° C., a rotor No. 4 and 30 rpm.

When the water absorption inhibitor of the present invention is prepared, a preservative, an antifungal agent, an algae inhibitor, a termite inhibitor, an ultraviolet absorber, etc. may be added as a secondary agent.

To apply the water-absorption preventing material of the present invention to a porous civil engineering building material, a roller, a brush, a spray or the like is used. As a drying method, it may be left standing at room temperature for drying, or may be sun drying or heat drying.

Examples of the porous civil engineering building materials to which the water absorption inhibitor of the present invention is applied include exposed concrete, lightweight concrete, precast concrete, lightweight expanded concrete (ALC), mortar, joint mortar, asbestos cement board, pulp cement board. , Wood wool cement board, cement-based extrusion board, glass fiber cement board (GR
C), carbon fiber cement board, calcium silicate board, gypsum board, hard board, plaster, plaster plaster, dolomite plaster, block, brick, tile, roof tile, natural stone, artificial stone, glass wool, rock wool, ceramic fiber, etc. A material containing a material as a main component; a material containing an organic material as a main component such as wood, plywood, and particle board.

When the water-absorption preventing material of the present invention is applied to a substrate, the alkylalkoxysilane or its condensate penetrates into the inside of the substrate, while the inorganic mineral, the water-soluble polymer and the water-absorbing resin are It remains on the material surface. As a result, the inorganic minerals, the water-soluble polymer and the water-absorbent resin play a so-called lid-like role and suppress volatilization of the alkylalkoxysilane or its condensate that is penetrating into the inside of the base material.
Almost the entire amount can be infiltrated into the substrate. Therefore, a deep permeation layer of an alkylalkoxysilane or a condensate thereof is formed on the surface layer of the base material, and the water absorption prevention properties such as water repellency, water absorption prevention property and salt shielding property can be maintained for a long period of time.

Therefore, the water-absorption preventive material of the present invention is characterized by leakage of rainwater due to severe wind and rain, deterioration of material due to acid rain, penetration of dirt, salt damage due to seawater, freezing damage in cold regions,
Various problems caused by water such as white sinter due to elution of salt in the material can be solved for a long period of time.

[0037]

The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

Example 1 80 parts by weight of hexyltrimethoxysilane, 10 parts by weight of bentonite (trade name; Organite, manufactured by Toyojun Yoko), 8 parts by weight of ethanol, and 2 parts by weight of water were stirred at high speed using a homomixer. By mixing, the water absorption preventive material of the present invention was obtained. The viscosity of the obtained water absorption preventing material was 650 mPa · s.

Example 2 80 parts by weight of octyltrimethoxysilane, 11 parts by weight of bentonite (trade name; manufactured by Sven, Toyojun Yoko), and 9 parts by weight of isopropyl alcohol were stirred and mixed at a high speed with a homomixer to prepare the present invention. A water absorption preventive material was obtained. The viscosity of the obtained water absorption preventive material was 820 mPa · s.

Example 3 20 parts by weight of water, sorbitan monolaurate (trade name: L
2 parts by weight (P-20R, manufactured by NOF CORPORATION) were mixed by stirring at high speed using a homomixer. Next, while gradually adding 72 parts by weight of hexyltriethoxysilane and 8 parts by weight of bentonite (trade name; Wenger, manufactured by Toyojun Yoko), the mixture was stirred and mixed at a high speed with a homomixer to obtain the water absorption inhibitor of the present invention. Obtained. The viscosity of the obtained water absorption inhibitor is 560 mPas.
・ It was s.

Example 4 75 parts by weight of octyltrimethoxysilane, hydroxyethyl cellulose (trade name; Fujichemi HEC SY-2)
(5, manufactured by Sumitomo Seika) 5 parts by weight, 10 parts by weight of ethanol, and 10 parts by weight of water were stirred and mixed at a high speed using a homomixer to obtain the water absorption inhibitor of the present invention. The viscosity of the obtained water-absorption preventing material was 450 mPa · s.

Example 5 20 parts by weight of water, sorbitan monolaurate (trade name: L
2 parts by weight (P-20R, manufactured by NOF CORPORATION) were mixed by stirring at high speed using a homomixer. Next, 75 parts by weight of hexyltriethoxysilane, hydroxyethyl cellulose (trade name; Fujichemi HEC SY-25, manufactured by Sumitomo Seika)
Using a homomixer while gradually adding 4 parts by weight,
The mixture was agitated and mixed at a high speed to obtain the water absorption inhibitor of the present invention. The viscosity of the obtained water absorption preventing material was 400 mPa · s.

Example 6 79 parts by weight of decyltrimethoxysilane, 1 part by weight of a cross-linked product of an acrylate polymer (trade name: Aquakeep 10SH-P, manufactured by Sumitomo Seika), 10 parts by weight of ethanol, 10 parts by weight of water Using a homomixer, the mixture was stirred and mixed at high speed to obtain the water absorption inhibitor of the present invention. The viscosity of the obtained water absorption inhibitor is
It was 1140 mPa · s.

Example 7 20 parts by weight of water, sorbitan monolaurate (trade name: L
2 parts by weight (P-20R, manufactured by NOF CORPORATION) were mixed by stirring at high speed using a homomixer. Then, 77 parts by weight of octyltriethoxysilane and 3 parts by weight of a cross-linked product of an acrylate polymer (trade name: Aquakeep SA60S, manufactured by Sumitomo Seika) are gradually added while stirring and mixing at high speed using a homomixer. Thus, the water absorption preventive material of the present invention was obtained. The viscosity of the obtained water absorption preventing material was 1850 mPa · s.

Comparative Example 1 90 parts by weight of hexyltrimethoxysilane, 1 part of ethanol
Using a homomixer, 0 parts by weight was stirred and mixed at a high speed to obtain a water absorption inhibitor. The viscosity of the obtained water-absorption preventing material is 10
It was mPa · s.

Comparative Example 2 20 parts by weight of water, sorbitan monolaurate (trade name: L
2 parts by weight (P-20R, manufactured by NOF CORPORATION) were mixed by stirring at high speed using a homomixer. Next, while gradually adding 80 parts by weight of hexyltriethoxysilane, a homomixer was used to stir and mix at high speed to obtain a water absorption inhibitor. The viscosity of the obtained water absorption inhibitor was 60 mPa · s.

Test Example JIS mortar (70 ×) according to JIS R-5201
70 × 20 mm) was used as a test piece, and the water absorption preventing materials obtained in Examples and Comparative Examples were applied on the entire surface at a rate of 300 g / m ² . Note that the one to which nothing was applied served as a control. The test piece obtained is at a temperature of 20 ° C. and a relative humidity of 65%.
After curing for 7 days in a thermo-hygrostat of RH, it was subjected to a performance test of penetration depth and water absorption ratio. Next, Sunshine Weather Meter (Ducycle Sunshine Super Long Life Weather Meter WEL-SUN-DCH
Type, manufactured by Suga Test Instruments Co., Ltd., an accelerated weather resistance test was carried out under the following test conditions: black panel temperature: 63 ° C., humidity: 50%, rainfall condition: rain for 12 minutes out of 60 minutes. 4000
After the lapse of time and 8000 hours, the test piece was subjected to a performance test of water absorption ratio. The method of the performance test will be described below.

(1) Penetration depth The obtained coated specimen was cut into two pieces, and water was sprayed on the cut surface to measure the thickness of the portion where water did not penetrate. The results are shown in Table 1.

(2) Water Absorption Ratio The coated and uncoated specimens thus obtained were immersed in water with the maximum surface area facing down (immersion depth 5 mm), taken out after 24 hours, and excess water was dried to dry cloth. After wiping with, the weight (g) was measured, and the water absorption ratio was calculated by the following formula. The results are shown in Table 2. When the water absorption ratio is 0.1 or less, it can be judged that the water absorption prevention property is excellent.

[0050]

[Equation 1]

[0051]

[Table 1]

[0052]

[Table 2]

It can be seen from Tables 1 and 2 that the water-absorption preventing materials of Examples 1 to 7 can maintain the water-absorption preventing performance for a long period of time because of the deep penetration depth.

[0054]

EFFECT OF THE INVENTION The water-absorption preventing material of the present invention is very excellent in the permeability to the inside of a base material such as a porous civil engineering building material, and by forming a deep penetration layer in the surface layer of the base material, Water can be prevented from entering for a long period of time, and the base material can be protected for a long period of time without changing the base material and texture of the material.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C09K 3/00 C09K 3/00 RF term (reference) 4H017 AA04 AA27 AA31 AB01 AB15 AB17 AC04 AC05 AC19 AD06 AE03 4J002 AB01X AB03X AB04X AB05X AD01X BB18X BE02X BG01X BG13X BH02X BN01X BQ00X CH02X CM01X CP03W DE027 DJ006 DJ036 EC037 EE037 ET007 FD016 FD207 GL00

Claims (8)

[Claims] 1. (A) Alkylalkoxysilane and / or
Alternatively, a water absorption preventive material comprising a condensate thereof, (B) an inorganic mineral, at least one of a water-soluble polymer and a water absorbing resin, and (C) a polar solvent. 2. (A) alkylalkoxysilane and / or
Or 60 to 95% by weight of a condensate thereof, (B) an inorganic mineral,
At least one of water-soluble polymer and water-absorbent resin 0.0
1 to 20% by weight, and (C) polar solvent 4 to 30% by weight
2. The water absorption preventive material according to claim 1. 3. An alkylalkoxysilane is represented by the following general formula (1); (Wherein R ¹ represents an alkyl group having 1 to 20 carbon atoms, R ² represents an alkyl group having 1 to 4 carbon atoms, and n is 1 or 2). Alternatively, the water absorption preventive material described in 2. 4. The water absorption preventing material according to claim 1, wherein the inorganic mineral is montmorillonite or bentonite. 5. The water-soluble polymer is hydroxyethyl cellulose, carboxymethyl cellulose, polyethylene oxide or sodium polyacrylate.
5. The water absorption preventive material according to any one of 4 to 4. 6. The water absorbent resin is a polyalkylene oxide modified product, a cross-linked product of an acrylate polymer, a cross-linked product of a starch-acrylate graft copolymer or an isobutylene-maleic anhydride copolymer. 1 to 5
A material for preventing water absorption according to item. 7. The water absorption inhibitor according to claim 1, wherein the polar solvent is water or alcohols. 8. The viscosity at 25 ° C. is 100 to 1000.
The water absorption preventive material according to any one of claims 1 to 7, which has a viscosity of 0 mPa · s.