JP5415686B2 - Soil surface layer modification silicone composition and production method thereof, surface modified soil and silicone-coated soil aggregate, soil modification method, and soil modification material construction method - Google Patents

Description

  The present invention relates to a silicone composition for soil surface layer modification, a method for producing the same, a surface-modified soil, a soil modification method, and a soil modification method. A silicone composition for soil surface layer modification that exhibits soil strengthening and plant germination inhibiting action by forming a silicone cured coating on the surface, and a method for producing the same, surface-modified soil and silicone-coated soil aggregate using the same, and The present invention relates to a soil improvement method.

For example, the harm caused by weeds in public places such as parks and golf courses, gardens of ordinary households, road dividers and sidebands, not only exacerbates aesthetics and discomfort, but also The effort spent to remove it is enormous. Especially on roads, the removal of weeds on the shoulders and side walls of highways is a prime example where a great deal of labor and cost is expended due to its large work area. For this reason, a drug is generally used to solve the problem, but the use of the drug may cause environmental pollution in some cases.
As this environmental pollution, for example, in the case of a herbicidal method using a herbicide of a root wiping system, the roots rooted in the soil are depleted or reduced, so the herbicidal effect is high, but on the other hand, it was stretched in the soil The loss of roots causes the soil to become less sticky, causing problems such as sediment runoff and sediment disasters caused by rainfall.
As another important issue, various pesticide preparations have been developed in recent years for the purpose of weed removal. Continual use is required, which not only increases the total cost, but also causes the problem of excessive use, which may cause destruction of biological systems and groundwater contamination.

As countermeasures for solving such problems, reactive silicone-based herbicidal materials having a herbicidal action have been proposed based on a soil modification technique using the hydrophobicity of silicone. For example, a polyalkylene glycol-added silicone compound (PGS) or a silicone-based curable composition is used as a method for controlling weeds in lawn vegetation, which has a long-lasting weed control effect and is prevented from being washed out by soil rainwater or water spray. The technique of spreading on the surface of lawn vegetation by using together is proposed (patent document 1). This is a method in which a silicone-based curable composition is added to prevent PGS having a weed control effect from flowing out due to rain water or water spray. The silicone-based curable composition can be selected from a silane material, a condensation reaction type silicone material, or an addition reaction type silicone material, and has an action of forming a cured film to prevent sediment discharge.
A composition containing 100 parts by weight of a specific Si-H bond-containing organopolysiloxane and 0.1 to 50 parts by weight of (B) a curing catalyst as a silicone-based herbicidal material having weed selectivity. Has been proposed for spraying 10 to 500 g / m ² on the lawn surface (Patent Document 2).
Furthermore, water solubility obtained by hydrolyzing 1 to 30 parts by weight of trialkoxysilane, 70 to 90 parts by weight of alkoxy group-containing siloxane and 1 to 20 parts by weight of amino group-containing alkoxysilane in the presence of an organic acid or an inorganic acid. A germination inhibitor comprising an organosilicon compound is disclosed (Patent Document 3).
Any of these can easily penetrate into the soil when sprayed on the surface of the soil, and then the soil is made hydrophobic so that the water supply necessary for germination of the plant seeds is cut off and the germination prevention effect is exhibited. It is.
In addition, a modified soil that has been subjected to silicone-based water repellent treatment has been proposed in which the soil is coated with a water-repellent treatment agent containing a water-based alkyd resin or a water-based silane resin (Patent Document 4).

However, in any of the above-mentioned measures, due to the water-based or emulsion-based structure, the problem of being easily washed away by rainwater after spraying is not considered enough. For this reason, it does not eliminate the continuation of regular use, which is another important issue, and has not yet solved the problem of causing the destruction of biological systems and contamination of groundwater.
In addition, these compositions have a viscosity increase if priority is given to the solution of environmental pollution problems such as groundwater contamination due to excessive penetration into the soil, even from the viewpoint of the spraying workability and environmental conservation. When spraying workability is prioritized, the spraying workability is significantly reduced. On the other hand, low viscosity increases the permeability, which, as described above, impairs consideration for environmental contamination, and is compatible with practical requirements. However, the technical idea does not solve the problem of improving the performance.
Reflecting these problems, all of the above-mentioned issues, including water-insoluble, moderate permeability and quick-drying spraying workability, and consideration of environmental pollution by maintaining the effect over a long period after spraying are all combined. The countermeasure was desired.
Furthermore, since the liquid herbicidal composition for soil application in the prior art has almost no permeability to clayey soil, there is a common problem that even if sprayed on an inclined surface, it flows immediately. Therefore, an effective measure for suppressing germination of plants that germinate quickly has been desired.
Furthermore, in the solution of the above-mentioned problems, there is an adverse effect of the application cost of applying for a drug when the herbicide is used and the extremely long acquisition period until market launch, and the competitiveness of the herbicide in a limited market is obtained. Considering this difficulty, it is also required to develop a new soil modifying material (composition) different from the herbicide.

Japanese Patent Laid-Open No. 05-025010 (Japanese Patent Publication No. 07-039326) JP 09-157117 A Japanese Patent Laid-Open No. 10-0455503 (Patent No. 3173383) Japanese Patent Laid-Open No. 2000-023559

  In view of the above problems, the object of the present invention is a non-aqueous and simple structure, can form a hardened film quickly after spraying, can exhibit excellent soil fixation and plant growth inhibitory action, A safe and environmentally friendly soil surface layer modifying silicone composition that is extremely low in load components and does not permeate or flow out into the ground, its production method, surface modified soil and silicone-coated soil aggregate, and soil modification method Another object of the present invention is to provide a method for constructing a soil modifying material for allowing the soil surface layer modifying silicone composition and the soil modifying method to function effectively in clay soil.

  As a result of intensive studies to solve the above problems, the present inventor contains a liquid room temperature curable polysiloxane having condensation reactivity, silicone oil, and filler in a specific ratio, and a viscosity at 25 ° C. in a specific range. When the prepared silicone composition is used as a fixing agent for soil surface treatment, a water-repellent film is formed on the soil surface, and a unique silicone-covered soil aggregate structure is formed on the soil surface while fixing the soil and entering the ground. It has been found that not only is it possible to prevent the infiltration of water into the soil and prevent the outflow of earth and sand due to rainwater, etc., but also it is effective in preventing the growth of weeds, as well as adding shock buffering and walking sensation. The present invention has been completed based on these findings.

  That is, according to the first aspect of the present invention, there is provided a silicone composition containing liquid room temperature curable polysiloxane (A) having condensation reactivity, silicone oil (B) and filler (C) as constituent components. The content of the constituent components is 20 to 80 parts by weight of the silicone oil (B) and 1 to 20 parts by weight of the filler (C) with respect to 100 parts by weight of the room temperature curable polysiloxane (A). And a viscosity of 50 to 2000 mPa · s at 25 ° C. is provided.

According to a second invention of the present invention, there is provided the soil surface layer modifying silicone composition according to the first invention, wherein the condensation functional group of the room temperature curable polysiloxane (A) is an oxime group. Provided.
According to a third aspect of the present invention, the silicone oil (B) has a kinematic viscosity at 25 ° C. of 50 mm ² / s or less, according to any one of the first and second aspects of the present invention. A silicone composition for surface layer modification is provided.
Furthermore, according to a fourth invention of the present invention, any one of the first to third inventions, wherein the filler (C) is silica having a specific surface area of 30 to 500 m ² / g by BET method. A silicone composition for modifying the soil surface layer is provided.

On the other hand, according to the fifth aspect of the present invention, after mixing the silicone oil (B) and the filler (C), the liquid room temperature curable polysiloxane (A) is mixed. A method for producing a silicone composition for surface layer modification is provided.
According to a sixth aspect of the present invention, the liquid room temperature curable polysiloxane (A) is mixed with the filler (C), and then the silicone oil (B) is added and mixed. A method for producing a silicone composition for modifying a soil surface layer is provided.
Further, according to a seventh invention of the present invention, the liquid room temperature curable polysiloxane (A) has a viscosity at 25 ° C. of 0.5 Pa · s or more, and is a fifth to sixth invention. A method for producing a silicone composition for modifying the soil surface layer is provided.

Moreover, according to the 8th invention of this invention, the hardening of the silicone composition for soil surface layer part modification | reformation of any one of Claims 1-4 coat | covered closely to the surface of earth and sand particles and the said earth and sand particles The surface-modified earth and sand characterized by comprising with a thing is provided.
Furthermore, according to the ninth invention of the present invention, a plurality of earth and sand particles are coated with a cured product of the silicone composition for soil surface layer modification according to any one of claims 1 to 4, and the earth and sand There is provided a silicone-coated earth and sand aggregate characterized in that particles are connected via the cured product.
Moreover, according to the tenth invention of the present invention, the soil surface layer modifying silicone composition of any one of the first to fourth inventions is sprayed on the soil surface to penetrate into the soil surface layer, and condensed and cured. There is provided a soil modification method characterized in that a surface modified soil layer is formed by connecting the structure of the soil surface layer with a cured product of the silicone composition.

Moreover, according to the eleventh aspect of the present invention, in any one of the first to fourth aspects, the ground to be subjected to soil modification is covered with the surface-modified soil of the eighth aspect, and then covered with the surface. A soil modifying material characterized in that the silicone composition for soil surface treatment according to claim 1 is sprayed and permeated to the ground to be condensed and hardened, and the surface-modified soil and the ground are connected with a cured product of the silicone composition. A construction method is provided.
Furthermore, according to the twelfth aspect of the present invention, pebbles (a) having a plurality of angular protrusions are spread on a clayey ground for soil modification, and then a part of the pebbles (a) is laid down. pressed to bite into the ground of the clay, and then on the ground in front Symbol clay and spread to fill the gap small gravel (b) the pebbles in diameter than the pebbles (a) (a) The soil covering material is formed by forming a soil covering layer and then spraying and curing the soil surface layer reforming silicone composition according to any one of claims 1 to 4 on the soil covering layer. A method is provided.

The silicone composition for soil surface layer modification according to the present invention is composed of a liquid room temperature curable polysiloxane (A), silicone oil (B) and filler (C) having condensation reactivity, and each component is specified. Since the composition has a specific viscosity, the composition can be easily sprayed and cured in a short time to form a cured film on the soil surface and surface layer. Prevents moisture from penetrating into the ground, not only preventing the collapse and loss of soil on slopes, but also effective in preventing the growth of weeds. Can greatly reduce the conventional labor and work costs.
In addition, it has a very low environmental impact component and does not permeate or flow into the basement, making it safe and environmentally friendly, so it can be used in a wide range of applications.
In addition, since the method for producing the silicone composition for modifying the soil surface layer of the present invention is adjusted to an appropriate viscosity, it can be produced without using a device such as a high-pressure homogenizer. A method for producing a silicone composition for soil surface treatment with high productivity and high productivity can be provided.
In addition, the surface-modified soil using the silicone composition for modifying the soil surface layer of the present invention can provide a weeding effect when used as a laying soil so as to cover the weeded soil, so that the exterior of a house or a park can be laid. It can be provided as a sand application member.
Furthermore, the effect of the silicone composition for modifying the soil surface layer portion can be obtained even in clay soil by the method for applying the silicone composition for modifying the soil surface layer of the present invention and the surface modified soil using the same. .

Below, the component of the silicone composition for soil surface layer modification | reformation of this invention, its manufacturing method, a use, etc. are demonstrated in detail.
The silicone composition for soil surface layer modification of the present invention is a silicone composition containing a liquid room temperature curable silicone rubber (A) having condensation reactivity, a silicone oil (B) and a filler (C), The content ratio thereof is 20 to 80 parts by weight of the silicone oil (B) and 1 to 5 parts by weight of the filler (C) with respect to 100 parts by weight of the room temperature curable silicone rubber (A). The viscosity at 50 ° C. is 50 to 2000 mPa · s.
The viscosity and kinematic viscosity were obtained in accordance with a viscosity measurement method using a coaxial double cylindrical rotational viscometer and Ubbelohde viscometer defined in JIS Z-8803-1991.

1. Component (i) Room Temperature Curing Polysiloxane (A) of Silicone Composition for Soil Surface Layer Modification
The room temperature curable polysiloxane (A) used in the present invention is a liquid room temperature curable polysiloxane having condensation reactivity, and the hydrolyzable functional group undergoes a hydrolysis condensation reaction by reacting with moisture in the atmosphere. It is raised and crosslinked to form a cured product having rubber-like elasticity (hereinafter referred to as a rubber elastic body). Examples of the hydrolysis functional group include a methyl ethyl ketoxime group (deoxime type), an acetoxy group (deacetic acid type), an alkoxy group (dealcohol type), and an isopropenoxy group (deacetone type), which are released. Dealcohol type or deoxime type with less corrosive and odorous substances are preferred, especially deoxime type, that is, room temperature of oxime type from the viewpoint of improving the action of preventing soil loss due to rainwater with high adhesion to soil. A curable polysiloxane is preferred.

Condensation-type reactive polysiloxane has, for example, a composition as follows:
(A) α, ω-dihydroxyorganopolysiloxane represented by the following general formula;

（式中、Ｒは、置換または非置換の１価の有機基、ｎは、３００〜３０００を示す。）

(In the formula, R represents a substituted or unsubstituted monovalent organic group, and n represents 300 to 3000.)

(B) an oxime silane represented by the following general formula:

（式中、Ｒ_１、Ｒ_２、Ｒ_３は、置換または非置換の１価の有機基を示す。）

(Wherein R ₁ , R ₂ and R ₃ represent a substituted or unsubstituted monovalent organic group.)

(C) a reinforcing filler such as silica, (d) a curing catalyst such as an organic metal, (e) an adhesion improver,
In some cases, the mixture is diluted with an organic solvent and applied to the surface of the substrate, and after drying and curing, an elastic film is formed.
The substituted or unsubstituted monovalent organic group in the above formula is preferably those having 10 or less carbon atoms, and particularly preferred are compounds such as methyl, ethyl, and vinyl.

The said oxime silane is a crosslinking agent or a hardening | curing agent, and forms a rubber elastic body by carrying out a hydrolysis condensation reaction with (a). By using oxime silane, the rubber elastic body exhibits excellent adhesion to soil.
As the oxime silane, for example, methyl-tris (methylethylketoxime) silane, vinyl-tris (methylethylketoxime) silane and the like are preferable.

  Examples of the liquid room temperature curable polysiloxane (A) having condensation reactivity include, for example, commercially available one-pack RTV rubber materials. Specifically, when the curing mechanism is a condensation type oxime type, Toray Dow Product name “SE5070” manufactured by Corning Co., Ltd., product name “TSE382” manufactured by GE Toshiba Silicone Co., Ltd., product names “KE45”, “KE44”, “KE441”, “KE445” manufactured by Shin-Etsu Chemical Co., Ltd. ”,“ KE4525 ”,“ KE402 ”, or the like.

(Ii) Silicone oil (B)
The silicone composition for modifying the soil surface layer of the present invention contains silicone oil (B) as an essential component.
The structure of the silicone oil (B) is not particularly limited, and is known as a silicone oil, for example, polydimethylsiloxane (dimethyl) having all methyl groups at the side chains and terminals of polysiloxane represented by the following general formula: Silicone oil), methylphenyl silicone in which part of the side chain of the polysiloxane is a phenyl group, and methyl hydrogen silicone oil in which part of the side chain of the polysiloxane is hydrogen.

The fast reactivity characteristic of the silicone composition for soil surface layer modification of the present invention depends on the volatility of the silicone oil (B), and the silicone oil (B) increases the volatility (boiling point). Low) from the viewpoint, low viscosity is good, specifically, the kinematic viscosity at 25 ° C. is preferably 50 mm ² / s or less, and as a commercially available product, the kinematic viscosity at 25 ° C. is from 0.65 mm ² / s to The thing of 50 mm < ² > / s can be used. When the kinematic viscosity exceeds 50 mm ² / s, the volatility is too low and the curing rate of the room temperature curable polysiloxane (A) becomes slow, the silicone oil (B) remains, the cured product swells, and the adhesive strength becomes weak. This causes a problem that the strength and water repellency of the cured film become weak.
Specific examples of the silicone oil (B) include, for example, a trade name “TSF451” series manufactured by GE Toshiba Silicone Co., Ltd., “TSF451-0.65”, “TSF451-10”, “TSF451-20”. “TSF451-30”, “TSF451-50”, “KF-96L-0.65cs” manufactured by Shin-Etsu Chemical Co., Ltd., and the like can be used.

(Iii) Filler (C)
In order to improve the adhesiveness with soil and the strength of the cured film of the silicone composition for soil surface layer modification, the silicone composition for soil surface layer modification of the present invention contains a filler (C). . Moreover, since thixotropy can be provided to the silicone composition for soil surface layer modification | reformation by adding a filler, it functions also as a viscosity modifier of the silicone composition for soil surface layer modification | reformation.
As the filler (filler or filler), known fillers such as fumed silica, surface-treated fumed silica, precipitated silica, diatomaceous earth, quartz powder, calcium carbonate, carbon black, magnesium oxide, titanium oxide, In addition to silicates (or complex oxides thereof) such as iron oxide, iron or aluminum, silane coupling agents can be used as adhesion improvers. Of these, silica-based silica having excellent dispersibility in polysiloxane is preferable, and hydrophobic fumed silica (hydrophobic fumed silica) is particularly preferable from the viewpoints of dispersibility and improvement in mechanical strength of the cured polysiloxane.
Moreover, as a specific surface area of a filler, it is preferable that it is 30-500 m < ² > / g. When the specific surface area of the filler is less than 30 m ² / g, the particle size becomes coarse and the mechanical strength of the cured product of the silicone composition becomes weak. Moreover, when the specific surface area of a filler exceeds 500 m < ² > / g, it will aggregate and a dispersibility will worsen.

As the filler (C), specifically, in the case of hydrophobic fumed silica, trade names “AEROSIL R972” and “AEROSIL R202” manufactured by Nippon Aerosil (or Degussa) may be mentioned. For example, “AEROSIL R972” Is a surface treatment of hydrophilic fumed silica with dimethyldichlorosilane, and the specific surface area by the BET method is approximately 110 m ² / g.

(Iv) Silicone composition for modifying the soil surface layer part The silicone composition for modifying the soil surface part of the present invention includes the liquid room temperature-curable polysiloxane (A) and silicone oil (B) having the condensation reactivity described above. And filler (C) are contained, and the content ratio thereof is 20 to 80 parts by weight, preferably 40 to 60 parts by weight of the silicone oil (B) with respect to 100 parts by weight of the room temperature curable polysiloxane (A). The filler (C) is 1 to 20 parts by weight, preferably 5 to 15 parts by weight. When the proportion of the silicone oil (B) is less than 20 parts by weight, the soil surface layer modifying silicone composition becomes highly viscous and the spraying workability is deteriorated, and when it exceeds 80 parts by weight, the volatilization time of the silicone oil (B) is reduced. Since it becomes long, a good cured film cannot be obtained because the mechanical strength is lowered after condensation curing. If the filler (C) is less than 1 part by weight, the soil surface layer modifying silicone composition will have poor adhesion to the soil and the cured strength after curing. The silicone composition thickens and the spraying workability deteriorates.
The silicone composition for modifying the soil surface layer of the present invention has a viscosity at 25 ° C. of 50 to 2000 mPa · s, preferably 300 to 700 mPa · s. When the viscosity at 25 ° C. is less than 50 mPa · s, since the amount of the silicone composition for modifying the soil surface layer adhering to the surface of the soil particles constituting the soil is too low, the adhesiveness is poor, and the viscosity is low. On the other hand, there is a problem that underground runoff occurs due to excessive viscosity. On the other hand, if it exceeds 2000 mPa · s, it is difficult to spread evenly due to high viscosity, and it is difficult to penetrate into the soil and it stays in a thick liquid pool on the soil surface. There is a risk that problems such as a considerably long curing time may occur.
What is necessary is just to adjust suitably the method of adjusting to predetermined viscosity within the range of said compounding conditions, such as the viscosity of said room temperature curable polysiloxane (A) and said silicone oil (B), and the specific surface area of a filler (C).

  In addition, the silicone composition for soil surface layer modification of the present invention does not interfere with the effects of the present invention, and the viscosity at 25 ° C. does not deviate from 10 to 2000 mPa · s. Auxiliaries and / or additives can be added, such as weathering stabilizers, dyes, pigments, antifouling agents, fungicides and bactericides, flame retardants and the like.

As the application rate of the soil surface layer portion modified silicone composition of the present invention, as appropriate, but are set, is preferably in the range of ^{0.1~6.0kg / m 2, 2~5kg / m} 2 Gayori preferable. When the application amount is less than 0.1 kg / m ² , a sufficient fixing effect cannot be given to the soil, and when it is more than 6 kg / m ² , it is economically disadvantageous.

2. Method for Producing Silicone Composition for Soil Surface Layer Modification As a method for producing a silicone composition for soil surface layer modification according to the present invention, specifically, it can take two modes and is a liquid having condensation reactivity. Depending on the appearance and viscosity properties of the room temperature curable polysiloxane (A), either one of the embodiments can be taken as appropriate.
As a first aspect, first, the silicone oil (B) and the filler (C) are mixed, and then the room temperature curable polysiloxane (A) is mixed. According to the production method of the first aspect, a soil surface layer modifying silicone composition that can be easily and uniformly dispersed regardless of the properties and blending ratios of the respective mixed components and has little variation in quality can be obtained.

  In a second embodiment, the filler (C) is mixed with the liquid room temperature curable polysiloxane (A), and then the silicone oil (B) is added and mixed. The production method of the second embodiment is effective when the filler (C) is precipitated and separated when the specific gravity of the filler (C) is large and mixed with the silicone oil (B). That is, by separating the filler (C) in the liquid room temperature curable polysiloxane (A) having a viscosity higher than that of the silicone oil (B), sedimentation and separation of the filler (C) is suppressed. As a result, a uniformly dispersed silicone composition for modifying the soil surface layer is obtained.

  The liquid room temperature curable polysiloxane (A) of the first and second embodiments preferably has a viscosity at 25 ° C. of 0.5 Pa · s or more. When the viscosity is less than 0.5 Pa · s, the effect of the present invention cannot be obtained by deviating (lowering) from the preferred viscosity range of the silicone composition for modifying the soil surface layer of the present invention. Since both the first and second aspects can be produced without using a device such as a high-pressure homogenizer, the silicone composition for modifying the soil surface layer is simple, efficient and highly productive. It becomes a manufacturing method of a thing.

3. Surface-modified soil coated with a silicone composition for soil surface layer modification The silicone composition for soil surface layer modification of the present invention can also be used as a surface treatment agent for soil particles, and the surface of soil particles is modified on the surface of the soil particles. By forming a cured film of the quality silicone composition, a surface-modified soil having water repellency is obtained. The earth and sand particles are composed of hard stone grains such as sand, gravel and pebbles constituting the earth and sand, fine powders and aggregates thereof, or composite aggregates thereof, and are aggregated in a natural state. It means a fixed granular material (or irregular shape).
The method for forming a cured film on the earth and sand particles is not particularly limited, but the silicone composition for soil surface treatment is dropped or sprayed while stirring the earth and sand with a mixing device such as a Henschel mixer, and water for hydrolysis is used as necessary. After adding a dry treatment method or adding soil to the silicone composition for modifying the soil surface layer, removing excess surplus silicone composition for modifying the soil surface layer and then subjecting the granulation to a condensation reaction in a wet atmosphere Alternatively, a wet processing method of stirring and granulating can be applied. Furthermore, a particle size adjustment or a disassembling process may be provided. In any step, it is desirable to perform a heat cure that completes the condensation reaction in the final step.

The form of the surface modified earth and sand is the form α in which a cured film of the silicone composition for modifying the soil surface layer is formed on the surface of the earth and sand particles, and the soil surface layer modification to a part or the whole of the internal voids of the earth and sand particles. There is a form β in which the silicone composition for use penetrates and a cured film is formed. Form α has impact shock-absorbing properties because it is easy for the sand particles to be released inside the hardened coating by an external force except in the case of stone grains, and is lighter than Form β because it has voids inside the sand particles. . Form β has high water repellency because a hardened film is formed up to the inside of the earth and sand particles and the surface modified surface area is large. Form β can also be solved somewhat by external force, but has a firm feel because it is firmly bonded to the cured coating. As described above, the surface-modified earth and sand of the present invention has different functions and feels depending on the form, and can be used alone or in combination depending on the application.
The form of the surface-modified earth and sand can be adjusted by the viscosity of the soil surface layer reforming silicone composition for treating the surface of the earth and sand particles. When the viscosity is high, form α tends to be obtained, and when the viscosity is low, form β is obtained.

4). Silicone-coated earth-and-sand aggregate The silicone-coated earth-and-sand aggregate is formed through a cured film having rubber elasticity by allowing the silicone composition for soil surface layer modification to permeate through the surface and voids of a plurality of earth-and-sand particles uniformly and condense and cure. A composite in which a plurality of earth and sand particles are connected. And since the earth and sand particles covered with the cured film of the above-mentioned silicone composition which has penetrated and hardened into the surface and the voids of the earth and sand particles are continuously connected via the adjacent earth and sand particles and the cured film, The encapsulated cell structure is an aggregate structure that is three-dimensionally connected, and the cured product that has penetrated and hardened into the gaps between the sediment particles becomes thicker than the sediment particle surface. The surface of the earth and sand particles is covered with a hardened film and a thick hardened material that is cured by filling the space between the particles, and is supported by a planar rubbery film and a thick rubber-like hardened material with dots or lines It can be used to provide shock buffering and haptic functions during walking.

In general, earth and sand particles are aggregates of fine particles other than one solid form such as gravel. Therefore, it is a well-known phenomenon that when treaded, agglomeration is broken and the shape is deformed. In addition, when this coagulation / disintegration is performed in a closed system, the volume of the aggregate tends to decrease, and in the case of wet earth and sand particles, a slight volume reduction and shape deformation accompanied by solid-liquid separation occurs. Since the surface-modified earth and sand structure of the present invention contains earth and sand particles in a substantially closed system, if physical force acts on the earth and sand particles, the particle cohesive failure also occurs in the three-dimensional cell structure in a substantially closed system. Occur. This earth and sand particle breakage consumes the applied stress (mechanical energy) in a state of cohesive breakage, and thus can be said to have a kind of impact absorbing effect. Further, since the above-mentioned silicone cured cell structure has an impact buffering effect due to the same elastic characteristics as the substantially closed foam also having an assembly in which the three-dimensionally connected cell structure is included, Due to the synergistic action of the earth and sand particles, a unique shock buffering and walking feel can be obtained. This silicone-coated earth and sand aggregate is laid like a weeding sheet when the silicone composition for soil surface layer modification cannot be sprayed, such as in places (agricultural land) where it cannot be used as herbicide applications regulated by the Agricultural Chemicals Control Law. By using it, the effect close | similar to the case where the silicone composition for soil surface layer modification | reformation is sprayed on soil is acquired. As an example of usage, it can be used as a weeding mat for farmland and bank, and in combination with the weeding effect, it has the effect of preventing shock and falling by improving the shock buffering and the feel of the scaffold during walking Is obtained.

5. Soil reforming method The soil reforming method of the present invention is a method of dispersing a silicone composition for soil surface layer reforming and infiltrating the inside of the soil surface to condense and harden the composition of the soil surface layer to cure the silicone composition. Connected with objects to form a surface-modified soil layer. Since the effect of soil modification depends on the degree of penetration of the silicone composition for modifying the soil surface layer into the soil, the composition of the silicone composition for modifying the soil surface layer of the present invention depends on the nature and type of the soil. Disperse the product with viscosity adjusted appropriately within the requirements. For soils with relatively large voids, adjust the viscosity to a high level, and for dense soils, adjust the viscosity to a low level. Moreover, what is necessary is just to adjust the viscosity and content rate of silicone oil (B) for adjustment of a cure rate.

6). Construction method of soil reforming material Any of the following construction methods can be applied as a soil reforming construction method using the silicone composition for soil surface layer modification of the present invention.
The first construction method is a construction method in which the silicone composition for soil surface layer modification according to the present invention is directly sprayed on soil, and is the simplest construction method.
The second construction method is to spread the surface-modified soil of the present invention on the ground on which soil modification is performed, and then spray the silicone composition for modifying the soil surface layer of the present invention on the covered soil. It is a construction method in which the surface-modified soil and the ground are connected with a cured product of the silicone composition by infiltrating to the ground and condensation-cured. In the second construction method, since the surface-modified soil has already been surface-modified with the silicone composition for modifying the soil surface layer portion, the soil surface layer modifying silicone is appropriately selected according to the preference of the voids of the surface-modified surface soil that has been spread. The composition may be sprayed and fixed, and the amount of spraying is small. Moreover, if the space | gap of the surface-modified earth and sand laid down is fully filled and hardened, an impact buffering effect and peculiar walk feeling can be obtained similarly to the silicone-coated earth and sand aggregate of the present invention. According to this construction method, the contact surface between the coating surface of the hardened surface-modified soil and the uncured soil surface layer reforming silicone composition to be dispersed later is the soil surface layer modifying silicone composition. Even if hardened, the adhesion between the surface-treated soil surface and the hardened surface of the soil surface layer modifying silicone composition is small, so that interfacial delamination occurs easily with a load during walking. Due to this phenomenon, unique walking feeling and impact buffering characteristics different from the silicone-coated earth and sand aggregate are developed.

The third construction method is a construction method for exerting the soil modifying action of the silicone composition for modifying the soil surface layer of the present invention even in clay soil. First, after laying pebbles (a) having a plurality of angular protrusions on a clay-like ground, the protrusions of the pebbles (a) are placed on the pebbles (a) with a known pressing means (for example, a pressing machine for civil engineering). so bite the ground argillaceous, then soil covering layer on the ground before Symbol clay and spread to fill the gap small gravel (b) the pebbles in diameter than the pebbles (a) (a) This is a construction method in which the silicone composition for modifying the soil surface layer portion is sprayed and cured on the soil covering layer. Since the silicone composition for modifying the soil surface layer portion is held while penetrating into the voids of the soil covering layer, the spread silicone composition for modifying the soil surface layer portion does not flow even on an inclined land. Further, the portion of the pebbles (a) encroached on the viscous ground has a spike action on the clay ground, and the covering layer is covered with the silicone composition for modifying the soil surface layer, and the slippage or slipping of the covering layer is carried out. To prevent. Moreover, as a structure of the said soil covering layer, it is good also as what forms the layer which spread | laid the surface modified earth and sand of this invention on the surface layer side from the pebbles (a), and the said surface modified earth and sand layer is installed internally. Thus, it is possible to impart a unique walking feeling to clayey soil.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not particularly limited to these examples.
[Example]
Silicone compositions having various viscosities were prepared with the compositions shown in Table 1. The adjustment method is shown below. Hydrophobic silica having a specific surface area of 110 m ² / g (“AEROSIL R972” manufactured by Degussa) and silicone oil having a kinematic viscosity at 25 ° C. of 0.65 mm ² / s [“KF-96L” manufactured by Shin-Etsu Chemical Co., Ltd. -0.65 cs "] was mixed and stirred to dissolve uniformly. A liquid room temperature-curing polysiloxane having a condensation reactivity with a viscosity at 25 ° C. of 5 Pa · s [“KE-445-T” manufactured by Shin-Etsu Chemical Co., Ltd.] is added to the mixture and stirred for 30 minutes. Example 1, 2, and 3 were obtained for 700 g of a milky white uniform dispersion, respectively.

(Evaluation results)
About the uncured liquid silicone composition obtained in Examples 1-3, performance evaluation was implemented with the following evaluation method.
(I) Germination suppression effect:
Commercial humus was put into a planter (30 cm × 13 cm × 13 cm) for 8 minutes, and 15 g of mizuna seeds were planted as grass in the soil about 1 cm deep from the surface. 200 mL of water was sprinkled with a joro from above. Four of these were prepared, three of which were sprayed with 200 g of the silicone compositions of Examples 1 to 3 (No. 1 to 3), and one was not sprayed with the silicone composition as a comparative example (No .4). After taking photographs of the grass generation after 10, 14, and 20 days, 200 mL of water was sprayed each time. The results are shown in Table 2.
In Nos. 1 to 3 sprayed with the silicone composition of the present invention, evaporation of the silicone oil started immediately after spraying, and then formation of a cured film was started by moisture in the air. When 24 hours had elapsed after spraying, a cured silicone film was completely formed. In these, no generation of grass was observed even after 20 days from spraying, but in No. 4 where the silicone composition was not sprayed, grass was generated after 10 days and grew smoothly until 20 days later. From the above results, it was found that the silicone composition of the present invention is effective in inhibiting plant germination.

(Ii) Water repellency:
About No. 1-3 which spread | dispersed the said silicone composition, the state in the soil was investigated after digging up soil 20 days later. As a result, the cured silicone formed a 3 to 5 mm thick film containing soil agglomerated particles on the soil surface, and no penetration of silicone into the soil or outflow from the bottom of the planter was observed. Moreover, the water | moisture content considered to be of the sprayed water and rain water collected on the surface of the silicone cured film, and there was almost no moisture in the soil. From the above results, it can be seen that the penetration of water into the soil is hindered by the formation of the water repellent film of the silicone composition on the soil surface. As a result, it is considered that the grass was not generated because the amount of water necessary for the germination of the grass was not supplied into the soil. In addition, when one side of the short side of the planter was lifted and tilted to about 45 °, water was sprayed at a rate of 2 liters / min with a watering can from the top for 5 minutes to confirm the soil runoff state of the soil. The surface soil was not caught and washed away.

(Iii) Impact buffering properties mulch is spread over a range of 100 cm × 200 cm with a layer thickness of 5 cm, and the silicone compositions of Examples 1 to 3 are sprayed in an amount three times as large as the above-described germination suppression effect verification test. Formed body. For comparison, a similar humus layer without spraying the silicone composition was used. The impact buffering test was evaluated based on the perceived impact when the subject naturally flew and landed on the surface of each silicone-coated earth and sand aggregate from a 50 cm height base. The test subjects were one female (45 kg, 55 kg) and four males (55 kg, 65 kg), and landed once in a separate place. As a result, when the silicone-coated earth and sand aggregate was formed, there was less body impact landing impact than when the silicone composition was not sprayed. In addition, after the test, the silicone-coated earth and sand aggregates of the landing portion and the non-landing portion were cut in the thickness direction and the cross section was observed. As a result, the soil particles were only finely broken.

(IV) Walking feel A silicone-coated earth and sand aggregate is formed in the same manner as in the shock-absorbing test described above, and is freely movable in the longitudinal direction (200 cm direction) with commercially available flat-bottomed athletic shoes for the same four subjects as in the test. We had you walk at walking speed and evaluated by sensory test to declare feeling when we walked. As a result, unlike the case of humus alone, the subject could feel as if he was walking on a sponge or long carpet.

  The silicone composition for modifying the soil surface layer of the present invention has a low environmental impact, is safe, can be easily applied, and can be cured in a short time to form a cured film with excellent water repellency on the soil surface and surface layer. Can be prevented, and the plant has excellent germination promoting action. Therefore, it can be suitably used for reinforcing shoulders and banks of highways and railway tracks and preventing germination. In addition, a silicone-coated soil aggregate is formed on the soil surface layer portion sprayed with the silicone composition for soil surface treatment of the present invention, and in addition to the prevention of sediment discharge and the suppression of plant germination, impact buffering and walking feeling Since it has, it can use suitably as a functional material of the civil engineering field | area of the walking path of a park, or a road shoulder.

Claims (12)

A silicone composition containing a liquid room temperature curable polysiloxane (A) having condensation reactivity, a silicone oil (B) and a filler (C) as constituent components,
The content of the component is 20 to 100 parts by weight of the silicone oil (B) and 1 to 20 parts by weight of the filler (C) with respect to 100 parts by weight of the room temperature curable polysiloxane (A). A soil surface layer modifying silicone composition characterized by having a viscosity at 25 ° C. of 10 to 2000 mPa · s. The silicone composition for soil surface layer modification according to claim 1, wherein the condensation functional group of the room temperature curable polysiloxane (A) is an oxime group. The silicone composition for soil surface treatment according to claim 1, wherein the silicone oil (B) has a kinematic viscosity at 25 ° C. of 50 mm ² / s or less. The silicone composition for soil surface treatment according to any one of claims 1 to 3, wherein the filler (C) is a silica having a specific surface area of 30 to 500 m ² / g by a BET method. A method for producing a silicone composition for soil surface treatment comprising a liquid room temperature curable polysiloxane (A) having condensation reactivity, a silicone oil (B) and a filler (C), the silicone oil (B) and After mixing the said filler (C), the said liquid room temperature curable polysiloxane (A) is added and mixed, The manufacturing method of the silicone composition for soil surface layer modification | reformation characterized by the above-mentioned. A method for producing a silicone composition for modifying a soil surface layer comprising a liquid room-temperature-curable polysiloxane (A) having condensation reactivity, a silicone oil (B) and a filler (C), wherein the liquid room-temperature curing is performed A method for producing a silicone composition for soil surface layer modification, comprising mixing the filler (C) with a polysiloxane (A) and then adding and mixing the silicone oil (B). The liquid room temperature curable polysiloxane (A) has a viscosity at 25 ° C of 0.5 Pa · s or more in a state before the start of the condensation reaction. Of producing a silicone composition for modifying the soil surface layer. A surface comprising the earth and sand particles and the cured product of the silicone composition for modifying the soil surface layer according to any one of claims 1 to 4, which is coated on the surface of the earth and sand particles. Modified earth and sand. A plurality of earth and sand particles are coated with the cured product of the silicone composition according to any one of claims 1 to 4, and the earth and sand particles are connected via the cured product. Earth and sand aggregate. The soil surface layer modification silicone composition according to any one of claims 1 to 4 is sprayed on the soil surface to infiltrate the inside of the soil surface layer to condense and harden the composition of the soil surface layer. A soil modification method comprising forming a surface-modified soil layer by connecting with a cured product. It is the construction method of a soil modifier, Comprising: The ground which constructs a soil modification is covered with the surface-modified soil according to claim 8, and then the place covered with the soil is any one of claims 1-4. The soil surface layer portion modification silicone composition is sprayed and infiltrated into the ground to be condensed and hardened, and the surface modified soil and the ground are connected with a cured product of the silicone composition. Material construction method. A method for constructing a soil modifying material, in which a pebble (a) having a plurality of angular protrusions is spread on a clayey ground on which soil modification is performed, and then a part of the pebble (a) is placed on the clay. pressed to bite into the ground quality, then soil covering layer on the ground before Symbol clay and spread to fill the gap small gravel (b) the pebbles in diameter than the pebbles (a) (a) And then curing the soil surface layer reforming silicone composition according to any one of claims 1 to 4 on the soil covering layer.