JP5653028B2 - Solidified composite material for vegetation greening and solid sand construction method for vegetation greening - Google Patents

Description

  The present invention is applied to a desert, for example, used to solidify a surface sand layer, prevent sand flow, and improve and secure water retention of the solidified sand layer surface when performing vegetation greening in a desert, etc. The present invention relates to a solidified composite material for vegetation greening and a solid sand construction method for vegetation greening.

  Currently, about 30% of the land in the world is desertified, and the area is still increasing. On the other hand, the world's population is increasing year by year, and there is a risk of a food crisis in the future as this population increases. To avoid this situation, we will prevent desertification of land, It is necessary to revitalize vegetation.

  Desertification refers to land degradation caused by various factors such as climate change and human activities in arid, semi-arid and arid semi-humid zones. The wind blows throughout the year. Along with this strong wind, the sand particles on the surface become sand and are carried by the wind, filling up everything on the surface (this phenomenon is called wind erosion). This wind erosion hinders the growth of plants, and is therefore a major factor in inhibiting vegetation greening in the desert. Therefore, it is necessary to prevent wind erosion in order to plant vegetation in desertified land. In addition, the desertified land has high ultraviolet irradiance, high ground surface temperature, and extremely high transpiration of the sand surface. That is, in order to prevent desertification and vegetation greening, it is necessary to simultaneously prevent wind erosion and ensure water retention.

  As a method for preventing wind erosion and vegetation greening a desert, a method of forming a solidified porous sand layer by spraying a solidifying composite material containing a hydrophilic polyurethane resin on sand has been proposed. In this method, it is preferable that the thickness of the solidified porous sand layer is 5 to 50 mm and the porosity in the porous sand layer is about 20%. In addition, vegetation is also possible by adding a step of spraying a vegetation greening composition containing plant seeds onto sand (see Patent Document 1).

JP 2009-27933 A

  However, when trying to apply the above method to areas with outstanding UV radiation and significant dry areas, hydrophilic polyurethane decomposes to UV before the plant is fully rooted and weakens sand fixation in the porous sand layer. Or the porous sand layer may be damaged.

  The present invention has been made in view of the above points, and can be used to prevent wind erosion and ensure water retention on the sand surface even in areas with a large amount of ultraviolet radiation or in extremely dry areas, and can be used to plant vegetation in the desert. The purpose is to provide a solidified composite material and a solid sand construction method for vegetation greening.

The solidified composite material for vegetation greening of the present invention comprises (a) a hydrophilic polyurethane resin, (b) water, and (c) a benzotriazole-based ultraviolet absorber having a benzotriazole group , and a hindered amine-based light stabilizer having a hindered amine group. The concentration of the hydrophilic polyurethane resin is in the range of 2 to 7% by weight, and the concentration of the ultraviolet absorber is in the range of 0.1 to 1% by weight. The concentration of the light stabilizer is in the range of 0.005 to 0.2% by weight, and is used for spraying on the desert surface.

  By spreading the solidified composite material for vegetation greening of the present invention onto, for example, the surface of sand, sand or fluid sand (dune) from the surface to a certain depth is combined and solidified in a porous form in a short time, A solidified porous sand layer can be formed. This solidified porous sand layer has high strength, durability and frost resistance, and prevents the movement of sand or dunes. In addition, the solidified porous sand layer is a porous structure (for example, laminated mat, net laminated, rubber laminated), so that vegetation for greening can be stably rooted (seed germination and seed germination). It also has functions for enabling initial vegetation), that is, water permeability, water retention, fertilizer retention, and moisture evaporation suppression.

  Therefore, if the solidified composite material for vegetation greening of the present invention is used, for example, there is no abundant groundwater, wind erosion is significant, and transpiration from the sand surface is large. Can be realized functionally and economically. Moreover, since the solidified composite material for vegetation greening of the present invention can be sprayed over a wide area and is excellent in economic efficiency, it can be applied to a vast desert area.

Moreover, since the solidification composite material for vegetation greening of this invention has high permeability with respect to sand, workability is good.
Furthermore, since the solidified composite material for vegetation greening of the present invention contains the component (c), the ultraviolet decomposition rate of the hydrophilic polyurethane can be controlled, the water retention can be improved, and vegetation can be more reliably performed. .

  That is, since the solidified composite material for vegetation greening of the present invention contains one or more selected from the group consisting of an ultraviolet absorber and a light stabilizer, the ultraviolet degradation of the hydrophilic polyurethane can be prevented. Therefore, even if the porous sand layer formed using the solidified composite material for vegetation greening of the present invention is irradiated with ultraviolet rays, the fixation of the sand is weakened or hardly damaged. As a result, water permeability, water retention, fertilizer retention, and moisture evaporation suppression can be maintained even in areas with a large amount of ultraviolet radiation.

In the solidified composite material for vegetation greening of the present invention, the concentration of the hydrophilic polyurethane resin is in the range of 2 to 7% by weight . By being 2% by weight or more, the reaction solidification time of the hydrophilic polyurethane resin can be shortened, the strength of the solidified porous sand layer is further increased, and the movement of sand or dunes is prevented even in a region where wind erosion is extremely remarkable. be able to. In addition, since it is 7% by weight or less, the solidified porous sand layer can secure voids (vegetation growth environment (house)) necessary for vegetation greening, and the effect of promoting vegetation greening is more remarkable. Become.

Dosage form of vegetation planting for solidifying the composite material of the present invention, Ru liquid form der. The hydrophilic polyurethane resin reacts with water in a short time to form a porous sand layer in which sand particles or other solid particles are bonded and solidified in the form of mesh fibers.

  The hydrophilic polyurethane resin can be produced, for example, as follows. That is, a compound having a molecular weight of 1000 to 20000 having two or more hydroxyl groups at the end and having a polyoxyethylene chain (also referred to as a polyethylene oxide compound), and a polyisocyanate compound having the same number of moles or more as the number of hydroxyl groups, Is produced by introducing isocyanate groups at both ends of the polyethylene oxide compound by reacting with a catalyst such as dibutyltin dilaurate or triethylenediamine as necessary at a temperature of 30 to 120 ° C. for 30 minutes to 7 days. Can do. The hydrophilic polyurethane resin thus obtained is liquid to paste at normal temperature and dissolves in 98 to 85% by weight of water with respect to 100 parts by weight of the hydrophilic polyurethane resin. This aqueous solution becomes a water-insoluble hydrated plastic with strong elasticity in 20 seconds to 2 hours.

The ultraviolet absorber absorbs harmful ultraviolet rays and improves the long-term weather resistance and stability of the plastic. Ultraviolet absorbers are benzotriazole-based ultraviolet absorber having a base benzotriazole group. The density | concentration of the ultraviolet absorber in the solidification composite material for vegetation greening of this invention exists in the range of 0.1 to 1 weight% . When the concentration of the ultraviolet absorber is 0.1% by weight or more, ultraviolet decomposition can be further reduced, and sand movement in the desert can be further prevented. Moreover, by being 1 weight% or less, the solidified porous sand layer can be decomposed | disassembled after several decades, and the influence which it has on vegetation greening and the surrounding environment can be suppressed. Moreover, since it is excellent in economical efficiency by suppressing the use amount of the benzotriazole ultraviolet absorber, it can be applied to a vast desert area.

The UV stabilizer protects the plastic from UV rays and does not absorb UV rays, but stabilizes it by efficiently capturing harmful free radicals generated by UV energy. Light stabilizers are hindered amine light stabilizer having a hindered amine group. The concentration of the UV stabilizer in the solidified composite material for vegetation greening of the present invention is 0.005 to 0.00. It is in the range of 2 % by weight. By being 0.005% by weight or more, ultraviolet decomposition can be further reduced, and sand movement in the desert can be further prevented. In addition, 0. By being 2 % by weight or less, the solidified porous sand layer can be decomposed after several decades, and the influence on vegetation greening and the surrounding environment can be suppressed. Moreover, since it is excellent also in economical efficiency by suppressing the usage-amount of a hindered amine light stabilizer, it can apply to a vast desert area.

The solid sand construction method for vegetation greening of the present invention is characterized by forming a solidified porous sand layer by spraying the above-mentioned solidified composite material for vegetation greening on the surface of sand.
According to the solid sand construction method for vegetation greening of the present invention, sand or fluid sand (dune) from a surface to a certain depth is shortened by spraying a solidified composite material for vegetation greening containing a hydrophilic polyurethane resin on the surface of the sand. Bonds and solidifies in a porous form over time, forming a solidified porous sand layer. This solidified porous sand layer has high strength, durability and frost resistance, and prevents the movement of sand or dunes. In addition, the solidified porous sand layer is a porous structure (for example, laminated mat, net laminated, rubber laminated), so that vegetation for greening can be stably rooted (seed germination and seed germination). It also has functions for enabling initial vegetation), that is, water permeability, water retention, fertilizer retention, and moisture evaporation suppression.

  Therefore, according to the solid sand construction method for vegetation greening of the present invention, vegetation greening is realized stably, functionally and economically even in a special environment peculiar to deserts, such as lack of abundant groundwater and remarkable wind erosion. can do. Further, the present invention can be applied over a large area (good workability) and is excellent in economic efficiency, and therefore can be applied to a vast desert area.

  Further, the solid sand construction method for vegetation greening of the present invention uses a hydrophilic polyurethane resin that is easily dissolved in water (which may be salt-containing water), and the solidified composite material for vegetation greening containing the hydrophilic polyurethane resin is sand. Because of its high permeability, the workability is good.

  Furthermore, since the solid sand construction method for vegetation greening of the present invention uses a solidified composite material for vegetation greening including at least one selected from the group consisting of an ultraviolet absorber and a light stabilizer, ultraviolet degradation of hydrophilic polyurethane is prevented. can do. Therefore, even if the porous sand layer formed using the solid sand construction method for vegetation greening of the present invention is irradiated with ultraviolet rays, the fixation of the sand is not weakened or damaged easily. As a result, water permeability, water retention, fertilizer retention, and moisture evaporation suppression can be maintained even in areas with a large amount of ultraviolet radiation.

  In the solid sand construction method for vegetation greening of the present invention, it is preferable to have a step of spraying a vegetation greening composition containing plant seeds on the sand before and / or after spraying the solidified composite material for vegetation greening. The vegetation greening composition preferably includes, for example, an appropriate amount of chemical fertilizer. In this way, seed germination and initial vegetation can be promoted. Moreover, it is preferable that a vegetation greening composition contains a lot of water. By carrying out like this, a vegetation greening composition can be penetrated deeply in sand. The permeated water is retained by the solidified porous sand layer having water retention, and can contribute to the initial growth of the plant. Examples of the fertilizer contained in the vegetation greening composition include animal (cow, sheep, etc.) feces, chemical fertilizer and the like. Moreover, as seeds contained in the vegetation greening composition, for example, 2-3 kinds of seeds having weather resistance, salt resistance, and drought resistance (for example, oil candy, silkworm, artemisia, carragana, etc.) can be mentioned.

  The vegetation greening composition may contain a water retention agent having water retention, for example. Examples of water retention agents include water retention polymers such as PVA (polyvinyl alcohol), MC (methyl cellulose), and CMC (carboxymethyl cellulose), water-absorbing polymers of acrylic polymers, inorganic perlite, montmorillonite, vermiculite. In addition, local ocher and clay can be listed. The water retention agent may be a polymer compound having water retention. The polymer compound may be a natural polymer or a synthetic polymer, but preferably does not destroy the desert environment to be used. Particularly in a desert region where drought is severe, it is preferable to use a so-called water-absorbing polymer as a water retention agent that has good water retention and can absorb water more than several hundred times its own weight.

  The vegetation greening composition preferably includes, for example, a material having fertilizer (fertilizer). Such materials include, for example, loosened animal (cow, sheep) feces produced and distributed locally to make them liquid, and ocher. Cow dung is particularly rich in fiber and is effective for solid sand or vegetation.

  The thickness of the solidified porous sand layer is preferably in the range of 5 to 50 mm. By being 5 mm or more, even in areas where wind erosion is significant, the effect of preventing the movement of sand or dunes is higher, and by being 50 mm or less, the amount of hydrophilic polyurethane resin to be used can be reduced, Excellent in workability and economy.

The compressive strength of the solidified porous sand layer is, for example, preferably in the range of 0.5 to 1.5 Kg / cm ² , and the tensile strength is preferably in the range of 0.2 to 0.5 Kg / cm ² , The porosity is preferably in the range of 25 to 10%. By being in these ranges, the effect of promoting vegetation greening is even higher. Each of the above characteristic values can be changed by adjusting the concentration of the hydrophilic polyurethane resin in the solidified composite material for vegetation greening.

  The solidified composite material for vegetation greening and the vegetation greening composition can be spread and infiltrated into the desert surface using, for example, a machine used for ordinary civil engineering (for example, a mortar sprayer, seed or water spreader). . Moreover, it can be sprayed and sprayed on the surface of sand by a machine with a special nozzle of Y-shaped tube system. Alternatively, a suction port with a needle valve (flow rate control valve) may be attached to the nozzle of an agricultural sprinkler, and the water may be mixed with the nozzle and sprayed while sucking at a constant rate.

  An embodiment of the present invention will be described.

  In the blending ratios shown in Table 1 and Table 2, hydrophilic polyurethane resin, water, and hindered amine light stabilizer were mixed to produce solidified composite materials for vegetation greening in Examples 1A to 1G and 3A to 3G.

なお、表１および表２におけるＪＣＫ−Ｗ−ＵＳは、ＪＣＫ株式会社製のヒンダードアミン系光安定剤である。また、表１および表２におけるＪＣＫ−ＯＨ１Ａは、ＪＣＫ株式会社製の、水を硬化剤として固化する親水性ポリウレタン樹脂の商品名である。JＪＣＫ−Ｗ−ＵＳ及びＪＣＫ−ＯＨ１Ａの物性は、それぞれ、以下のとおりである。
（ＪＣＫ−Ｗ−ＵＳ）
外観：淡黄色液体
化学名：ビス（１，２，２，６，６−ペンタメチル−４−ピペリジル）セバケート
比重（２５℃）：０．９９１
屈折率（２５℃）：１．４４７
分子量：５０９
（ＪＣＫ−ＯＨ１Ａ）
外観：無色〜淡黄色液体
主成分：親水性ポリウレタン樹脂
粘度（２０℃ｍＰa・ｓ）：３００〜６００
比重（２０℃／４℃）：１．０８±０．０５
硬化時間（２０℃）：配合ＪＣＫ−ＯＨ１Ａ／水＝１０／９０、３〜６分

Note that JCK-W-US in Tables 1 and 2 is a hindered amine light stabilizer manufactured by JCK Corporation. Moreover, JCK-OH1A in Table 1 and Table 2 is a brand name of the hydrophilic polyurethane resin made from JCK Corporation and solidified by using water as a curing agent. The physical properties of JJCK-W-US and JCK-OH1A are as follows.
(JCK-W-US)
Appearance: Light yellow liquid Chemical name: Bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate Specific gravity (25 ° C.): 0.991
Refractive index (25 ° C.): 1.447
Molecular weight: 509
(JCK-OH1A)
Appearance: colorless to pale yellow liquid Main component: hydrophilic polyurethane resin Viscosity (20 ° C. mPa · s): 300 to 600
Specific gravity (20 ° C / 4 ° C): 1.08 ± 0.05
Curing time (20 ° C.): Formulation JCK-OH1A / water = 10/90, 3-6 minutes

  In the blending ratios shown in Table 3 and Table 4, hydrophilic polyurethane resins, water, and benzotriazole ultraviolet absorbers were mixed to produce solidified composite materials for vegetation greening in Examples 2A to 2E and 4A to 4E.

なお、表３および表４におけるＪＣＫ−Ｗ−ＵＡは、ＪＣＫ株式会社製のベンゾトリアゾール系紫外線吸収剤である。ＪＣＫ−Ｗ−ＵＡの物性は以下のとおりである。
（ＪＣＫ−Ｗ−ＵＡ）
外観：淡黄色結晶性粉末
化学名：2-（2'−ヒドロキシ−5’−メチルフェニル）ベンゾトリアゾール
融点：１２６〜１３２℃
分子量：２２５

In Tables 3 and 4, JCK-W-UA is a benzotriazole ultraviolet absorber manufactured by JCK Corporation. The physical properties of JCK-W-UA are as follows.
(JCK-W-UA)
Appearance: Pale yellow crystalline powder Chemical name: 2- (2′-hydroxy-5′-methylphenyl) benzotriazole Melting point: 126-132 ° C.
Molecular weight: 225

The solid sand construction method for vegetation greening was implemented as follows.
(1) Creation of a desert model A cylindrical mold (diameter 50 mm x depth 100 mm) is filled with Toyoura standard sand (produced by Toyoura Soseki Mining Co., Ltd., specific gravity d = 2.60), and the sand thickness is obtained by moderate compaction. A desert model was made with a gap ratio of 40%.
(2) Dispersion of solidified composite material for vegetation greening Solidified composite material for vegetation greening having the same composition as in Examples 1A to 1G, 2A to 2E, 3A to 3G, and 4A to 4E, respectively, on the sand surface in the desert model Scattered. Specifically, components other than water (hydrophilic polyurethane resin, hindered amine light stabilizer, benzotriazole ultraviolet absorber) in the solidified composite for vegetation greening are mixed in advance, and the mixture and water are Y-shaped. It was mixed by a machine with a pipe type special nozzle and sprayed on the sand surface in the desert model. The composition of the aqueous solution sprayed on the sand surface was the same as the solidified composite material for vegetation greening in Examples 1A to 1G, 2A to 2E, 3A to 3G, and 4A to 4E. The amount of application was 3.0 L per 1 m ^{2 of the} desert model surface.

The solidified composite material for vegetation greening penetrates from the surface of the sand to a predetermined depth, and the hydrophilic polyurethane resin contained therein binds the sand particles to solidify between the surface of the sand and the predetermined depth. A porous sand layer was formed. Water is retained in the voids in the solidified porous sand layer.
(3) Test for confirming the effect of the present invention A desert model (hereinafter referred to as a test body) after spraying the solidified composite material for greening of vegetation is a high energy type xenon weather manufactured by CO.FO.ME.GRA. It put into the meter (Solarbox1500e) (henceforth a test machine), and irradiated with the ultraviolet-ray with the average ultraviolet irradiation amount of 1000 W / m < ² >. At this time, the environmental setting temperature was 45 ° C., and the measured value during the test was 44 ± 1 ° C.
The test machine was stopped every 24 hours from the start of the test, (X) the weight measurement of the test specimen as it was, and (Y) the sand that was not fixed and accumulated on the test specimen surface was sucked with a dust suction machine The above test specimens were measured for receipt. The measurement result of (X) in the n-th stop of the testing machine is Wnx, and the measurement result of (Y) is Wny.
The amount of water evaporated from the n-th stop to the (n + 1) -th stop is calculated by Wny−W (n + 1) x. Tables 2 and 4 show the integrated values from the start of the test of the amount of transpiration moisture.
Further, the amount of sand released by ultraviolet irradiation from the n-th stop to the (n + 1) -th stop is calculated by W (n + 1) x-W (n + 1) y. Tables 1 and 3 show the integrated values from the start of the test for the amount of free sand (indicated as “weight reduction” in Tables 1 and 3).

  In addition, as a comparative example, for a test specimen sprayed with an aqueous solution consisting of only a hydrophilic polyurethane resin and water (the concentration of the hydrophilic polyurethane resin is the same as the solidified composite material for vegetation greening in each example) on a desert model, A similar test was conducted. The results are shown in Tables 1 to 4 above.

  As is clear from Tables 1 and 3, for the specimens sprayed with the solidified composite material for vegetation greening having the same composition as in Examples 1A to 1G and 2A to 2E, the decrease in weight before and after suction was small. On the other hand, in the test sample of the comparative example in which an aqueous solution composed only of a hydrophilic polyurethane resin and water was sprayed, the amount of weight reduction before and after suction was significantly large.

  Moreover, as Table 2 and Table 4 clearly, about the test body which sprayed the solidification composite material for vegetation greening of the composition similar to Example 3A-3G and 4A-4E, the amount of transpiration | moisture contents was small. On the other hand, the amount of transpiration water was remarkably large in the test sample of the comparative example in which an aqueous solution consisting only of the hydrophilic polyurethane resin and water was sprayed.

Needless to say, the present invention is not limited to the above-described embodiments, and can be implemented in various modes without departing from the scope of the present invention.
For example, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate instead of bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate as a hindered amine light stabilizer Even if it is used, substantially the same effect can be obtained.

  In addition, as a benzotriazole ultraviolet absorber, 2- (2′-hydroxy-3-t-butyl-5′-methylphenyl) instead of 2- (2′-hydroxy-5′-methylphenyl) benzotriazole -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-t-amylphenyl) -benzotriazole, 2- (2'-hydroxy-5'-t-octylphenyl) -benzo Even if triazole or the like is used, substantially the same effect can be obtained.

Claims (3)

1 or more types chosen from the group which consists of (a) hydrophilic polyurethane resin, (b) water, and (c) the benzotriazole type ultraviolet absorber which has a benzotriazole group , and the hindered amine type light stabilizer which has a hindered amine group are included. ,
The concentration of the hydrophilic polyurethane resin is in the range of 2 to 7% by weight,
The concentration of the ultraviolet absorber is in the range of 0.1 to 1% by weight;
The concentration of the light stabilizer is in the range of 0.005 to 0.2% by weight;
A solidified composite material for liquid vegetation planting, characterized by being applied to the surface of a desert. A solid sand construction method for vegetation greening, wherein the solidified porous sand layer is formed by spraying the solidified composite material for vegetation greening according to claim 1 on the surface of sand. The solid sand construction method for vegetation revegetation according to claim 2 , comprising a step of spreading a vegetation revegetation composition containing plant seeds on the sand before and / or after the application of the solidified composite material for vegetation revegetation. .