A viscosity-reducing water-reducing agent for promoting concrete flow and a preparation method thereof

Abstract

The invention discloses a viscosity-reducing water reducer for promoting concrete flow and a preparation method thereof, which belongs to the technical field of water reducers. First, the preparation method of the water reducer comprises the following steps: mixing isopentanol polyoxyethylene ether and deionized water, stirring and heating until the solid components are completely dissolved, then stirring and adding aqueous hydrogen peroxide solution, acrylic acid, methacrylic acid and branched monomers thereto, then stirring and adding ammonium persulfate, mercaptoethanol and a reducing agent, after the addition is completed, stirring and reacting for 3 to 4 hours, cooling to room temperature, and obtaining a viscosity-reducing water reducer for promoting concrete flow. The present invention adopts isopentanol polyoxyethylene ether, acrylic acid, methacrylic acid and homemade branched monomers for multi-component copolymerization to prepare a viscosity-reducing water reducer for promoting concrete flow. After testing, the water reducer prepared by the present invention has excellent viscosity-reducing effect and the effect of promoting concrete flow while ensuring excellent water-reducing effect, and the effect is more durable.

Description

Technical Field

[0001] The invention belongs to the technical field of water reducing agents, and in particular relates to a viscosity-reducing water reducing agent for promoting concrete flow and a preparation method thereof. Background Art

[0002] Traditional water reducers improve the fluidity and construction performance of concrete through dispersion, lubrication and steric hindrance. Water reducer molecules are directionally adsorbed on the surface of cement particles, releasing the enclosed water and increasing the fluidity of the concrete mixture. Although traditional water reducers can improve the fluidity of concrete, as the requirements for concrete strength increase, the water-cement ratio of concrete gradually decreases. In the process of preparing low water-cement ratio concrete, the viscosity of the concrete produced by traditional water reducers is high, making construction more difficult. Many improvements have been made in the existing technology:

[0003] The Chinese invention patent with application publication number CN117820631A discloses a branched viscosity-reducing monomer and a branched viscosity-reducing polycarboxylic acid water-reducing agent and a preparation method thereof. The invention patent achieves a viscosity-reducing effect by introducing a side chain with a branched structure, and enhances the adsorption capacity of the water-reducing agent on cement by introducing a phosphate group, thereby finally achieving a viscosity-reducing effect. Summary of the invention

[0004] On the basis of the prior art, the present invention further improves the structure of the water reducing agent, further enhances the setting point reducing effect and concrete flow promoting effect of the water reducing agent, and enhances the durability of the effect.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A method for preparing a viscosity-reducing water-reducing agent for promoting concrete flow comprises the following steps:

[0007] The isopentanol polyoxyethylene ether and deionized water are mixed, stirred, and heated to 50-60°C, and the stirring is continued until the solid component is completely dissolved, and then a 30% by mass fraction of hydrogen peroxide aqueous solution is added thereto, stirred for 10 minutes, and then acrylic acid, methacrylic acid and branched monomers are added thereto, stirred for 20-30 minutes, and then ammonium persulfate, mercaptoethanol and reducing agent are added thereto, and after the addition is completed, the reaction is stirred for 3-4 hours. After the stirring reaction is completed, it is cooled to room temperature to obtain a viscosity-reducing water reducer for promoting the flow of concrete.

[0008] Furthermore, the dosage ratio of the isopentanol polyoxyethylene ether, deionized water, 30% hydrogen peroxide aqueous solution by mass, acrylic acid, methacrylic acid, branched monomer, ammonium persulfate, mercaptoethanol and reducing agent is 100 g: 100 g: 1.5-2.0 g: 18-19 g: 21.5-22.0 g: 37-40 g: 0.5 g: 1.0-1.1 g: 0.4-0.5 g.

[0009] Furthermore, the isopentanol polyoxyethylene ether is TPEG-1200.

[0010] Furthermore, the reducing agent is reducing agent E51.

[0011] Furthermore, the branched monomer is prepared by the following steps:

[0012] S1. Add 2-carboxyphenyl phosphate, diethanolamine and p-toluenesulfonic acid to toluene with stirring, heat to 80-90°C, stir and react for 4-5 hours. After the reaction is completed, remove toluene by rotary evaporation, cool to room temperature, and obtain an intermediate. The intermediate is prepared by esterification reaction between the carboxyl group of 2-carboxyphenyl phosphate and the hydroxyl group of diethanolamine. The preparation process of the intermediate is as follows:

[0013] .

[0014] S2, adding methanol to the reactor, and then filling nitrogen to replace the air in the reactor, and then adding the intermediate prepared above, after the addition is completed, stirring and mixing for 30 minutes, and then stirring and dropping allyl acrylate therein, after the dropwise addition is completed, stirring and heating the reactor to 40-50° C., stirring and reacting at a constant temperature for 3-4 hours, after the reaction is completed, removing methanol by rotary evaporation, cooling to room temperature, and obtaining a branched monomer, which is prepared by Michael addition reaction of the secondary amine group in the intermediate and the unsaturated double bond of allyl acrylate, and the branched monomer includes two structures, namely branched monomer one and branched monomer two, and the preparation process of the branched monomer is as follows:

[0015] ;

[0016] .

[0017] Furthermore, the usage ratio of toluene, 2-carboxyphenyl phosphate, diethanolamine and p-toluenesulfonic acid in S1 is 200 mL: 0.2 mol: 0.1 mol: 0.5-1.0 g.

[0018] Furthermore, the usage ratio of methanol, intermediate and allyl acrylate in S2 is 100 mL:30.5-31.0 g:0.1 mol.

[0019] Furthermore, a viscosity-reducing water-reducing agent for promoting concrete flow is prepared by the above steps.

[0020] Beneficial effects of the present invention:

[0021] The present invention adopts isopentanol polyoxyethylene ether, acrylic acid, methacrylic acid and self-made branched monomer for multi-component copolymerization to prepare a viscosity-reducing water reducer for promoting concrete flow. According to the test, the water reducer prepared by the present invention has excellent viscosity-reducing effect and the effect of promoting concrete flow while ensuring excellent water-reducing effect (water-reducing rate is 27.0% to 27.4%), and the effect is more durable.

[0022] The branched monomer prepared by the present invention has a terminal phosphate group, a tertiary amino group, an ester group, a hydroxyl group and a carbon-carbon double bond structure participating in copolymerization. At the same time, the branched monomer is a macromolecular segment structure as a whole. The present invention finally achieves the enhancement of viscosity reduction and promotion of concrete flow by performing the above-mentioned structural design on the branched monomer. The specific principle is as follows:

[0023] The macromolecular segment structure can increase the steric hindrance of the water reducer. The extended part of the water reducer molecule forms a space barrier between concrete particles (cement, standard sand, fly ash and other common components), preventing the close aggregation of concrete particles and maintaining the high fluidity of concrete. However, simply improving the segment structure of the water reducer has a poor durability in promoting the fluidity of concrete. Therefore, the present invention further introduces terminal phosphate groups, tertiary amino groups, ester groups and hydroxyl groups to improve the durability of the high fluidity of concrete. At the same time, the presence of the above groups helps to achieve viscosity reduction performance. The specific principle is as follows:

[0024] The terminal phosphate group is negatively charged and can coordinate with metal ions (calcium ions, etc.) in concrete. Its complexing and adsorption capabilities are stronger than those of the carboxyl group, which makes the surface of concrete particles carry an electric charge. The electrostatic effect can prevent the concrete particles from agglomerating, thereby directly reducing the viscosity between concrete particles. The reduction in viscosity between concrete particles can further improve the fluidity of concrete. At the same time, tertiary amino, ester and hydroxyl groups also have the ability to form coordination bonds with metal ions in concrete. Moreover, tertiary amino, ester and hydroxyl groups are easily combined with water molecules by hydrogen bonds to form a solvated water film, which also plays a steric hindrance role. Moreover, the solvated water film can provide lubrication for concrete particles, reduce friction between them, and thus help maintain the fluidity of concrete, thereby comprehensively improving the viscosity reduction effect and the durability of the concrete fluidity enhancement effect. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0026] Example 1

[0027] Preparation of branched monomers:

[0028] S1. Add 200 mL of toluene (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) into reactor A, and then add 0.2 mol of 2-carboxyphenyl phosphate (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 0.1 mol of diethanolamine (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) and 0.5 g of p-toluenesulfonic acid (CP; purchased from Sinopharm Chemical Reagent Co., Ltd.) into the reactor A with stirring, heat the reactor A to 80°C, stir and react for 4 h, after the reaction is completed, remove toluene by rotary evaporation, and cool to room temperature to obtain an intermediate;

[0029] S2. Add 100 mL of methanol (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) into reactor B, then fill with nitrogen to replace the air in reactor B, then add 30.5 g of the intermediate into reactor B, after the addition is complete, stir and mix for 30 minutes, then add 0.1 mol of allyl acrylate (95%; purchased from Sinopharm Chemical Reagent Co., Ltd.) dropwise therein with stirring, after the addition is complete, stir and heat reactor B to 40°C, stir and react at constant temperature for 3 hours, after the reaction is complete, remove methanol by rotary evaporation, and cool to room temperature to obtain a branched monomer.

[0030] Example 2

[0031] Preparation of branched monomers:

[0032] S1. Add 200 mL of toluene (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) into reactor A, and then add 0.2 mol of 2-carboxyphenyl phosphate (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 0.1 mol of diethanolamine (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) and 0.8 g of p-toluenesulfonic acid (CP; purchased from Sinopharm Chemical Reagent Co., Ltd.) into the reactor A with stirring. Heat the reactor A to 85°C and stir for 5 h. After the reaction is completed, remove the toluene by rotary evaporation and cool to room temperature to obtain an intermediate.

[0033] S2. Add 100 mL of methanol (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) into reactor B, then fill with nitrogen to replace the air in reactor B, then add 31.0 g of the intermediate into reactor B, after the addition is complete, stir and mix for 30 minutes, then add 0.1 mol of allyl acrylate (95%; purchased from Sinopharm Chemical Reagent Co., Ltd.) dropwise therein with stirring, after the addition is complete, stir and heat reactor B to 45°C, stir and react at constant temperature for 4 hours, after the reaction is complete, remove methanol by rotary evaporation, and cool to room temperature to obtain a branched monomer.

[0034] Example 3

[0035] Preparation of branched monomers:

[0036] S1. Add 200 mL of toluene (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) into reactor A, and then add 0.2 mol of 2-carboxyphenyl phosphate (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 0.1 mol of diethanolamine (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) and 1.0 g of p-toluenesulfonic acid (CP; purchased from Sinopharm Chemical Reagent Co., Ltd.) into the reactor A with stirring. Heat the reactor A to 90°C and stir for 5 h. After the reaction is completed, remove the toluene by rotary evaporation and cool to room temperature to obtain an intermediate.

[0037] S2. Add 100 mL of methanol (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) into reactor B, then fill with nitrogen to replace the air in reactor B, then add 31.0 g of the intermediate into reactor B, after the addition is complete, stir and mix for 30 minutes, then add 0.1 mol of allyl acrylate (95%; purchased from Sinopharm Chemical Reagent Co., Ltd.) dropwise therein with stirring, after the addition is complete, stir and heat reactor B to 50°C, stir and react at constant temperature for 4 hours, after the reaction is complete, remove methanol by rotary evaporation, and cool to room temperature to obtain a branched monomer.

[0038] Example 4

[0039] Preparation of viscosity-reducing water-reducing agent to promote concrete flow:

[0040] 100 g of isopentanol polyoxyethylene ether (TPEG-1200; weight average molecular weight of 1200; purchased from Liaoning Fushun Dongke Fine Chemical Co., Ltd.) and 100 g of deionized water were added to the reactor. After the addition was completed, the reactor was stirred and heated to 50°C at a heating rate of 5°C / min, and continued to stir until the solid component was completely dissolved. Then, 1.5 g of a 30% mass fraction of hydrogen peroxide aqueous solution (CP; purchased from Sinopharm Chemical Reagent Co., Ltd.) was added to the reactor and stirred for 10 min. Then, 18 g of acrylic acid (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 21.5 g of methacrylic acid (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) and 37 g of the branched monomer prepared in Example 1 were added to the reactor and stirred for 20 min. Then, 0.5 g of ammonium persulfate (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 1.0 g of mercaptoethanol (purchased from Guangdong Zhonghe High-tech Co., Ltd.) and 0.4 g of reducing agent E51 (purchased from Brüggemann Chemical Co., Ltd., Germany) was added, stirred and reacted for 3 h. After the stirring reaction was completed, it was cooled to room temperature to obtain a viscosity-reducing water-reducing agent that promotes the flow of concrete.

[0041] Example 5

[0042] Preparation of viscosity-reducing water-reducing agent to promote concrete flow:

[0043] 100 g of isopentanol polyoxyethylene ether (TPEG-1200; weight average molecular weight of 1200; purchased from Liaoning Fushun Dongke Fine Chemical Co., Ltd.) and 100 g of deionized water were added to the reactor. After the addition was completed, the reactor was stirred and heated to 56°C at a heating rate of 8°C / min, and the stirring was continued until the solid component was completely dissolved. Then, 2.0 g of a 30% mass fraction of hydrogen peroxide aqueous solution (CP; purchased from Sinopharm Chemical Reagent Co., Ltd.) was added to the reactor and stirred for 10 min. Then, 18.5 g of acrylic acid (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 22.0 g of methacrylic acid (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) and 40 g of the branched monomer prepared in Example 2 were added to the reactor and stirred for 30 min. Then, 0.5 g of ammonium persulfate (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 1.1 g of mercaptoethanol (purchased from Guangdong Zhonghe High-tech Co., Ltd.) and 0.5 g of reducing agent E51 (purchased from Brüggemann Chemical Co., Ltd., Germany) was added, stirred and reacted for 4 h. After the stirring reaction was completed, it was cooled to room temperature to obtain a viscosity-reducing water-reducing agent that promotes the flow of concrete.

[0044] Example 6

[0045] Preparation of viscosity-reducing water-reducing agent to promote concrete flow:

[0046] 100 g of isopentanol polyoxyethylene ether (TPEG-1200; weight average molecular weight of 1200; purchased from Liaoning Fushun Dongke Fine Chemical Co., Ltd.) and 100 g of deionized water were added to the reactor. After the addition was completed, the reactor was stirred and heated to 60°C at a heating rate of 10°C / min, and continued to stir until the solid component was completely dissolved. Then, 2.0 g of a 30% mass fraction of hydrogen peroxide aqueous solution (CP; purchased from Sinopharm Chemical Reagent Co., Ltd.) was added to the reactor and stirred for 10 min. Then, 19 g of acrylic acid (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 22.0 g of methacrylic acid (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.) and 40 g of the branched monomer prepared in Example 3 were added to the reactor and stirred for 30 min. Then, 0.5 g of ammonium persulfate (AR; purchased from Sinopharm Chemical Reagent Co., Ltd.), 1.1 g of mercaptoethanol (purchased from Guangdong Zhonghe High-tech Co., Ltd.) and 0.5 g of reducing agent E51 (purchased from Brüggemann Chemical Co., Ltd., Germany) was added, stirred and reacted for 4 h. After the stirring reaction was completed, it was cooled to room temperature to obtain a viscosity-reducing water-reducing agent that promotes the flow of concrete.

[0047] Comparative Example 1

[0048] Comparative Example 1 is the control group of Example 5, in which the branched monomer prepared in Example 2 in Example 5 is replaced with vinyl acetate (99%; purchased from Sinopharm Chemical Reagent Co., Ltd.), and the rest of the preparation process remains unchanged, and finally a viscosity-reducing water reducer for promoting concrete flow is obtained.

[0049] Test Example 1

[0050] The performance test of the viscosity-reducing water-reducing agent for promoting concrete flow (hereinafter referred to as water-reducing agent) prepared in Examples 4 to 6 and Comparative Example 1 was carried out. The test process is as follows, and the results are shown in Table 1:

[0051] Fluidity of cement paste: The fluidity of cement paste (cement + water + water reducing agent) was tested with reference to GB / T 8077-2012 “Test method for homogeneity of concrete admixtures”. Cement P.042.5 (purchased from Yatai Group Yitong Cement Co., Ltd.) was used, the water-cement mass ratio was 0.29, the water reducing agent dosage was 1% of the cement mass, and the initial fluidity of the cement paste and the fluidity of the cement paste after standing for 30 minutes were tested.

[0052] Marsh time: Marsh time test was carried out in accordance with JC / T 1083-2008 “Test method for compatibility of cement and water reducing agent”, wherein P.042.5 cement (purchased from Yatai Group Yitong Cement Co., Ltd.) was used, the water-cement ratio was adjusted to 0.24, the water reducing agent dosage was 1% of the cement mass, and the time required for the cement paste to fill a 300 mL measuring cup was measured when the fluidity of the cement paste was 230 mm.

[0053] Expansion: The expansion test was carried out in accordance with GB / T 50080-2016 "Standard for Test Methods for Performance of Ordinary Concrete Mixtures". 450 g of cement (P.042.5; purchased from Yatai Group Yitong Cement Co., Ltd.), 200 g of fly ash (Grade II; purchased from Gansu Bocheng Microsilica Fume Co., Ltd.), 1350 g of standard sand (fineness modulus of 2.7%; purchased from Tongwei County Tianrun Sand Factory) and 450 g of water were put into a mixing pot, and then 40 g (cement + fly ash + standard sand total mass 2%) of water reducer was added to the mixing pot, and the mixing pot was turned on for stirring to obtain concrete mortar sand (cement + fly ash + standard sand + water + water reducer), and the initial expansion of the concrete mortar sand and the expansion after 30 min were tested.

[0054] Water reduction rate: refer to GB / T 8077-2012 "Test method for homogeneity of concrete admixtures" for water reduction rate test, wherein 450 g of cement (P.042.5; purchased from Yatai Group Yitong Cement Co., Ltd.), 200 g of fly ash (Grade II; purchased from Gansu Bocheng Microsilica Fume Co., Ltd.), 1350 g of standard sand (fineness modulus is 2.7%; purchased from Tongwei County Tianrun Sand Factory) and 100 g of water are put into a mixing pot, the mixing pot is turned on for stirring, and the expansion of the concrete mortar sand is tested, and water is continued to be added to the mixing pot until the expansion of the concrete mortar sand reaches 180 mm. The total water consumption is recorded as m0, and then 40 g (2% of the total mass of cement + fly ash + standard sand) of water reducer is added. After stirring and mixing, water is added to the mixing pot again until the expansion of the concrete mortar sand reaches 180 mm again. When the water consumption is mm, the total water consumption is recorded as m1, and the water reduction rate W of concrete mortar sand can be calculated by the following formula: W = (m1-m0) × 100% / m0.

[0055] Table 1 Performance test results

[0056]

[0057] It can be seen from the data in Table 1 that the water reducing agents prepared in Examples 4 to 6 of the present invention have excellent viscosity reducing effects and the effects of promoting concrete flow while ensuring excellent water reducing effects.

[0058] Among them, the viscosity reduction effect can be characterized by the fluidity of cement paste and Marsh time data. First, the greater the fluidity of cement paste, the better the flowability of cement paste (cement + water + water reducing agent) and the smaller the apparent viscosity; then, the longer the Marsh time, the worse the flowability of cement paste and the greater the apparent viscosity. From the data comparison of Example 5 and Comparative Example 1, it can be seen that the use of the water reducing agent prepared in Example 5 of the present invention can significantly reduce the apparent viscosity of cement paste, so it has excellent viscosity reduction effect, and the durability of the viscosity reduction effect is more excellent, belonging to a viscosity reduction type water reducing agent.

[0059] Among them, the effect of promoting the flow of concrete can be characterized by the expansion data. The larger the expansion of the concrete mortar sand (cement + fly ash + standard sand + water + water reducing agent), the better the flow performance of the concrete mortar sand. From the comparison of the data of Example 5 and Comparative Example 1, it can be obtained that the use of the water reducing agent prepared in Example 5 of the present invention can significantly promote the flow of concrete, and the durability of the concrete fluidity is stronger.

[0060] It should be noted that, in this article, terms such as "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or equipment that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment.

[0061] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a viscosity-reducing water-reducing agent for promoting concrete flow, characterized in that: The following steps are involved: Mix isopentanol polyoxyethylene ether and deionized water, stir and heat to 50-60°C, continue stirring until the solid component is completely dissolved, then stir and add 30% by mass fraction of hydrogen peroxide aqueous solution, stir for 10 min, then add acrylic acid, methacrylic acid and branched monomer, stir for 20-30 min, then stir and add ammonium persulfate, mercaptoethanol and reducing agent, stir and react for 3-4 h after the addition is complete, and cool to room temperature after the stirring reaction is complete to obtain a viscosity-reducing water-reducing agent for promoting concrete flow; The branched monomer is prepared by the following steps: S1. Add 2-carboxyphenyl phosphate, diethanolamine and p-toluenesulfonic acid to toluene with stirring, heat to 80-90° C., stir and react for 4-5 h. After the reaction is completed, remove toluene by rotary evaporation, and cool to room temperature to obtain an intermediate. S2, adding methanol to the reactor, and then filling nitrogen to replace the air in the reactor, and then adding the intermediate prepared above, after the addition is completed, stirring and mixing for 30 minutes, and then adding allyl acrylate dropwise thereto with stirring, after the dropwise addition is completed, stirring and heating the reactor to 40-50° C., stirring and reacting at a constant temperature for 3-4 hours, after the reaction is completed, removing methanol by rotary evaporation, and cooling to room temperature to obtain a branched monomer; The amount ratio of toluene, 2-carboxyphenyl phosphate, diethanolamine and p-toluenesulfonic acid in S1 is 200 mL: 0.2 mol: 0.1 mol: 0.5-1.0 g; The amount ratio of methanol, intermediate and allyl acrylate in S2 is 100 mL:30.5-31.0 g:0.1 mol; The dosage ratio of the isopentanol polyoxyethylene ether, deionized water, 30% hydrogen peroxide aqueous solution by mass, acrylic acid, methacrylic acid, branched monomer, ammonium persulfate, mercaptoethanol and reducing agent is 100 g: 100 g: 1.5-2.0 g: 18-19 g: 21.5-22.0 g: 37-40 g: 0.5 g: 1.0-1.1 g: 0.4-0.5 g.

2. The method for preparing a viscosity-reducing water-reducing agent for promoting concrete flow according to claim 1, characterized in that: The isopentanol polyoxyethylene ether is TPEG-1200.

3. The method for preparing a viscosity-reducing water-reducing agent for promoting concrete flow according to claim 1, characterized in that: The reducing agent is reducing agent E51.

4. A viscosity-reducing water-reducing agent for promoting concrete flow, characterized in that: The invention is prepared by the preparation method according to any one of claims 1 to 3.

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