Algae-inhibiting solid water-reducing agent and preparation method therefor

Abstract

The present invention relates to an algae-inhibiting solid water-reducing agent and a preparation method therefor. The algae-inhibiting solid water-reducing agent is prepared from the following raw materials in parts by weight: 5-12 parts of a small monomer having algae-killing and anti-corrosion functions, 260-320 parts of a polyether macromonomer, 10-16 parts of an unsaturated ester small monomer, 32-40 parts of an unsaturated acid small monomer, 0.8-1.6 parts of a chain transfer agent, 2.4-3.0 parts of an initiator, and xylene. The algae-inhibiting solid water-reducing agent prepared in the present invention has good algae-inhibiting performance, certain slump-retaining performance and good water-reducing performance, can ensure that a polycarboxylic acid water-reducing agent does not deteriorate for a long time without the need to add an additional preservative, can be used alone, and can also be compounded with other water-reducing agents for use.

Description

An anti-algae solid water reducer and its preparation method

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the Chinese patent application with application number 202311819487.1 filed with the Chinese Patent Office on December 27, 2023, entitled "An anti-algae solid water reducer and its preparation method", the entire contents of which are incorporated by reference into this application. Technical Field

[0003] The present invention relates to the technical field of concrete, in particular to an algae-inhibiting solid water reducing agent and a preparation method thereof. Background Art

[0004] Polycarboxylate superplasticizers offer broad development prospects due to their key advantages, including low dosage, high water reduction rate, high slump retention, and environmentally friendly production and use. Polycarboxylate superplasticizers are often combined with functional components such as retarding components, early strength components, defoaming components, and air-entraining components to enhance the performance of concrete in various areas. These components are mostly organic and can provide nutrients for the growth of bacteria, yeasts, molds, and algae. Sodium gluconate, a widely used retarding component, is mostly produced through microbial fermentation, which may harbor traces of Aspergillus niger.

[0005] In addition, unclean production, storage and transportation containers or pipelines with bacteria, production water or storage tanks with algae, and other auxiliary small materials will bring microorganisms such as fungi and bacteria into the polycarboxylate water reducer. In such an environment, microorganisms multiply rapidly, causing the polycarboxylate water reducer to mold.

[0006] Mildew problems with polycarboxylate superplasticizers are particularly common during high summer temperatures, during seaborne exports, and during extended shutdowns. These problems can lead to deterioration and odor, swelling or even rupture of sealed containers, stratification or precipitation, and the appearance of flocculent or slimy floating materials on the liquid surface. These factors not only cause financial losses but also degrade product performance and pose a risk to concrete quality.

[0007] Summary of the Invention

[0008] Based on this, it is necessary to provide an algaecide-type solid water reducer with algaecide and antiseptic effect and its preparation method.

[0009] To achieve the above object, the present invention provides a technical solution:

[0010] An algae-inhibiting solid water reducer, wherein the raw materials for preparing the algae-inhibiting solid water reducer include, in parts by weight:

[0011] Preferably, the raw materials for preparing the algaecide and antiseptic functional small monomer include, by weight:

[0012] Preferably, the dehalogenating agent comprises at least one of diisopropylethylamine and triethylamine.

[0013] Preferably, the polymerization inhibitor includes at least one of p-hydroxyanisole and hydroquinone.

[0014] Preferably, the polyether macromonomer comprises at least one of ethylene glycol monovinyl polyethylene glycol ether and methyl allyl alcohol polyoxyethylene ether having a molecular weight of 2000-4000.

[0015] Preferably, the unsaturated ester small monomer includes at least one of methyl methacrylate, ethyl methacrylate and hydroxyethyl methacrylate.

[0016] Preferably, the unsaturated acid small monomer is one or more of acrylic acid, methacrylic acid, maleic anhydride, and fumaric acid.

[0017] Preferably, the chain transfer agent comprises at least one of thioglycolic acid and thioethanol.

[0018] The present invention also provides a method for preparing an algae-inhibiting solid water-reducing agent, comprising the steps of:

[0019] Mixing the polyether macromonomer and xylene to obtain component A;

[0020] Mixing the unsaturated ester small monomer, the unsaturated acid small monomer and xylene to obtain component B;

[0021] Ultrasonic dissolution of the algaecide and antiseptic functional small monomer, the chain transfer agent, and xylene to obtain component C;

[0022] The initiator, the component B and the component C are added dropwise to the component A. After the addition is completed, the mixture is kept warm for 1 to 3 hours to complete the reaction and obtain a reaction product. Specifically, the reaction temperature is 80° C. to 95° C.

[0023] The xylene in the reaction product is removed by distillation under reduced pressure to obtain the algae-inhibiting solid water-reducing agent.

[0024] Preferably, the steps of preparing the algaecide and antiseptic functional small monomer include:

[0025] Mixing the 2-n-octyl-4-isothiazoline-3-one and toluene to obtain a first mixture;

[0026] adding the dehalogenating agent and the polymerization inhibitor to the first mixture to obtain a second mixture, stirring the second mixture and heating it to reflux;

[0027] The mixed solution of allyl chloroformate and toluene is added dropwise to the second mixture in a reflux state. After the addition is completed, the reflux reaction is continued for 4 to 6 hours. After the reaction is completed, the mixture is washed with water, dried, concentrated, and crystallized to obtain the algaecide and antiseptic functional small monomer.

[0028] Beneficial effects of the present invention:

[0029] The algae-inhibiting solid water-reducing agent prepared by the invention is in a solid state, can be stored for a long time without deterioration, and is convenient to package and transport.

[0030] The preparation method of the present invention is simple and easy to industrialize; the organic solvent used can be recycled and reused, thus avoiding waste of resources and being environmentally friendly.

[0031] The algae-inhibiting solid water reducer prepared by the present invention has good algae-inhibiting performance, certain collapse-preserving performance and good water-reducing performance, and can keep the polycarboxylate water reducer from deteriorating for a long time without the need for adding preservatives. The invention can be used alone or in combination with other water reducers. DETAILED DESCRIPTION

[0032] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below with reference to specific embodiments.

[0033] In the examples, the test methods used are conventional methods unless otherwise specified, and the materials, reagents, etc. used are all commercially available unless otherwise specified.

[0034] An algae-inhibiting solid water reducer, wherein the raw materials for preparing the algae-inhibiting solid water reducer include, in parts by weight:

[0035] Specifically, the structural formula of the small monomer with algaecide and antiseptic functions is as follows:

[0036] The structural formula of the algae-inhibiting solid water reducer is as follows:

[0037] More specifically, the molecular weight of the algae-inhibiting solid water reducer is 20,000 to 60,000.

[0038] In one embodiment, the raw materials for preparing the algaecide and antiseptic functional small monomer include, by weight:

[0039] Specifically, the algae-inhibiting solid water reducer will gradually release BIT (2-n-octyl-4-isothiazoline-3-one) molecules in water. The NS bond in the BIT molecule will destroy the protein thiol in the algae, thus having good algae-inhibiting properties.

[0040] In one embodiment, the dehalogenating agent comprises at least one of diisopropylethylamine and triethylamine.

[0041] In one embodiment, the polymerization inhibitor includes at least one of p-hydroxyanisole and hydroquinone.

[0042] In one embodiment, the polyether macromonomer includes at least one of ethylene glycol monovinyl polyethylene glycol ether and methyl allyl alcohol polyoxyethylene ether with a molecular weight of 2000-4000.

[0043] In one embodiment, the unsaturated ester small monomer includes at least one of methyl methacrylate, ethyl methacrylate, and hydroxyethyl methacrylate.

[0044] In one embodiment, the unsaturated acid monomer is one or more of acrylic acid, methacrylic acid, maleic anhydride, and fumaric acid, preferably hydroxyethyl methacrylate and acrylic acid.

[0045] In one embodiment, the chain transfer agent includes at least one of thioglycolic acid and thioethanol.

[0046] In one embodiment, the initiator includes azobisisobutyronitrile.

[0047] The present invention also provides a method for preparing an algae-inhibiting solid water-reducing agent, comprising the steps of:

[0048] Mixing the polyether macromonomer and xylene to obtain component A;

[0049] Mixing the unsaturated ester small monomer, the unsaturated acid small monomer and xylene to obtain component B;

[0050] Ultrasonic dissolution of the algaecide and antiseptic functional small monomer, the chain transfer agent, and xylene to obtain component C;

[0051] Add the initiator, the B component and the C component dropwise to the A component, and keep the mixture warm for 1 to 3 hours after the addition is complete. The reaction is completed to obtain a reaction product.

[0052] The xylene in the reaction product is removed by distillation under reduced pressure to obtain the algae-inhibiting solid water-reducing agent.

[0053] In one embodiment, the steps of preparing the algaecide and antiseptic functional small monomer include:

[0054] Mixing the 2-n-octyl-4-isothiazoline-3-one and toluene to obtain a first mixture;

[0055] adding the dehalogenating agent and the polymerization inhibitor to the first mixture to obtain a second mixture, stirring the second mixture and heating it to reflux;

[0056] The mixed solution of allyl chloroformate and toluene is added dropwise to the second mixture in a reflux state. After the addition is completed, the reflux reaction is continued for 4 to 6 hours. After the reaction is completed, the mixture is washed with water, dried, concentrated, and crystallized to obtain the algaecide and antiseptic functional small monomer.

[0057] Example

[0058] 1. Preparation of small monomers with algaecide and antiseptic functions

[0059] The preparation steps are as follows:

[0060] Mixing the 2-n-octyl-4-isothiazoline-3-one and toluene to obtain a first mixture;

[0061] adding the dehalogenating agent and the polymerization inhibitor to the first mixture to obtain a second mixture, stirring the second mixture and heating it to reflux;

[0062] The mixed solution of allyl chloroformate and toluene is added dropwise to the second mixture in a reflux state. After the addition is completed, the reflux reaction is continued for 4 hours. After the reaction is completed, the heating is turned off and the mixture is naturally cooled. The reaction solution is washed with deionized water and dried, concentrated, and crystallized to obtain the algaecide and antiseptic functional small monomer.

[0063] The raw materials for preparing the small monomers with algaecide and antiseptic functions in Examples 1 to 7 are shown in Table 1.

[0064] Table 1 Raw materials for preparing small monomers with algaecide and antiseptic functions in Examples 1 to 7

[0065] 2. Preparation of algae-inhibiting solid water reducer

[0066] The preparation steps are as follows:

[0067] Mix 260-320 parts of a polyether macromonomer and 90-120 parts of xylene to obtain component A;

[0068] Mix 10-16 parts of unsaturated ester small monomer, 32-40 parts of unsaturated acid small monomer and 25-30 parts of xylene to obtain component B;

[0069] Ultrasonic dissolution of 5-12 parts of a small monomer with algaecide and antiseptic function, 0.8-1.6 parts of a chain transfer agent, and 38-42 parts of xylene is performed to obtain component C;

[0070] The initiator, the component B and the component C are added dropwise to the component A. After the addition is completed, the mixture is kept warm for 1 to 3 hours to complete the reaction and obtain a reaction product. The reaction temperature is 80° C. to 95° C.

[0071] The xylene in the reaction product is removed by distillation under reduced pressure to obtain the algae-inhibiting solid water-reducing agent.

[0072] The raw materials and reaction conditions for preparing algae-inhibiting solid water-reducing agents in Examples 1 to 7 are shown in Table 2.

[0073] Table 2 Raw materials and reaction conditions for preparing algae-inhibiting solid water reducer

[0074] Comparative Example 1

[0075] The other conditions are the same as those in Example 1. When preparing the algaecide-type solid water reducer, no algaecide-preservative monomer is added.

[0076] Comparative Example 2

[0077] The rest is the same as in Example 1. When preparing the small monomer with algaecide and antiseptic function, 2-n-octyl-4-isothiazoline-3-one is replaced with 2-methyl-4-isothiazoline-3-one.

[0078] Performance testing:

[0079] 1. Water reducing performance

[0080] Water reduction rate tests were conducted using the algaecide and anticorrosive polycarboxylate water-reducers obtained in Examples 1-7, compared with a commercially available polycarboxylate water-reducer Point-400 without an added preservative and a commercially available polycarboxylate water-reducer with a Kasson preservative. The test method was based on the GB 8076-2008 standard, "Concrete Admixtures." The water reduction rate test results are shown in Table 3.

[0081] Table 3 Concrete performance test results

[0082] From the data in Table 3 above, it can be seen that the water-reducing performance of the algaecide and antiseptic polycarboxylic acid of the present invention is above 25% within 270 days. In the commercial polycarboxylic acid water-reducing agent without preservatives, the water-reducing rate drops due to spoilage at 28 days, and drops to 21.7% at 270 days. When the commercial polycarboxylic acid water-reducing agent with the addition of the preservative Kasson does not show a drop in water-reducing rate until 180 days, and drops to 22.5% at 270 days. This shows that the algaecide and antiseptic polycarboxylic acid of the present invention can maintain excellent water-reducing performance for 270 days.

[0083] 2. Algaecide and antiseptic properties

[0084] Test method: Equal amounts of the fungus suspension were added to the algaecide and preservative polycarboxylate water reducer obtained in Examples 1 to 7, a commercial polycarboxylate water reducer without preservatives, and a commercial polycarboxylate water reducer with a kason preservative, and the mixture was cultured at a constant temperature of 28°C.

[0085] The initial colony count was recorded before the sample was placed in the culture dish. Samples were taken at 28 days, 90 days, 180 days, and 270 days, and the sample conditions were observed. The test results were recorded as shown in Table 4.

[0086] Table 4 Algaecide and antiseptic test results

[0087] Note: “-” means the liquid is clear and no bacteria grows, “+” means there is slight corruption, and “+++++” means there is serious corruption. The more + the number, the more serious the corruption.

[0088] The data in Table 4 above show that, as can be seen from the comparison, the algaecide and antiseptic polycarboxylic acid of the present invention showed almost no signs of corruption within 270 days. However, the commercially available polycarboxylic acid water-reducing agent without preservatives showed significant corruption at 28 days, with floccules appearing in the liquid and very few molds on the liquid surface. By 90 days, corruption had become severe, with the liquid becoming dark red and a large area of ​​mold covering the surface. When the commercially available polycarboxylic acid water-reducing agent with the addition of the Kasson preservative did not show corruption until 180 days, with floccules precipitating. At 270 days, corruption was more severe. Comparative Example 1, because the algaecide and antiseptic small monomer was not introduced during synthesis, the synthesized product lacked algaecide and antiseptic properties and showed corruption at 28 days. In Comparative Example 2, 2-n-octyl-4-isothiazoline-3-one was replaced with 2-methyl-4-isothiazoline-3-one during the synthesis. Since 2-methyl-4-isothiazoline-3-one decomposed at high temperature during the reaction, the synthesized product did not have algaecide and antiseptic properties, and corruption occurred after 28 days.

[0089] It can be seen that the algaecide and antiseptic polycarboxylic acid in the present invention has excellent algaecide and antiseptic performance.

[0090] It should be noted that the specific parameters or some reagents in the above embodiments are specific embodiments or preferred embodiments under the concept of the present invention, and are not intended to limit the present invention; those skilled in the art can make adaptive adjustments within the concept and protection scope of the present invention.

Claims

1. An algae-inhibiting solid water reducing agent, characterized in that: The raw materials for preparing the algae-inhibiting solid water reducing agent include, by weight:

2. The algae-inhibiting solid water reducing agent according to claim 1, characterized in that: The raw materials for preparing the algaecide and antiseptic functional small monomer include, by weight:

3. The algae-inhibiting solid water reducing agent according to claim 2, characterized in that: The dehalogenating agent includes at least one of diisopropylethylamine and triethylamine.

4. The algae-inhibiting solid water reducing agent according to claim 2, characterized in that: The polymerization inhibitor includes at least one of p-hydroxyanisole and hydroquinone.

5. The algae-inhibiting solid water reducing agent according to claim 1, characterized in that: The polyether macromonomer includes at least one of ethylene glycol monovinyl polyethylene glycol ether and methyl allyl alcohol polyoxyethylene ether with a molecular weight of 2000-4000.

6. The algae-inhibiting solid water reducing agent according to claim 1, characterized in that: The unsaturated ester small monomer includes at least one of methyl methacrylate, ethyl methacrylate and hydroxyethyl methacrylate.

7. The algae-inhibiting solid water reducing agent according to claim 1, characterized in that: The unsaturated acid monomer is one or more of acrylic acid, methacrylic acid, maleic anhydride, and fumaric acid, preferably hydroxyethyl methacrylate and acrylic acid.

8. The algae-inhibiting solid water reducing agent according to claim 1, characterized in that: The chain transfer agent includes at least one of thioglycolic acid and thioethanol.

9. A method for preparing the algae-inhibiting solid water reducing agent according to any one of claims 1 to 8, characterized in that: Includes steps: Mixing the polyether macromonomer and xylene to obtain component A; The unsaturated ester small monomer, the unsaturated acid small monomer and xylene are mixed to obtain a B component; Ultrasonic dissolving the algaecide and antiseptic functional small monomer, the chain transfer agent and xylene to obtain component C; Add the initiator, the B component and the C component dropwise to the A component, and keep the temperature for 1 to 3 hours after the addition is completed, and the reaction is completed to obtain a reaction product; The xylene in the reaction product is removed by distillation under reduced pressure to obtain the algae-inhibiting solid water-reducing agent.

10. The method for preparing the algae-inhibiting solid water reducing agent according to claim 9, characterized in that: The steps of preparing the algaecide and antiseptic functional small monomer include: Mixing the 2-n-octyl-4-isothiazoline-3-one and toluene to obtain a first mixture; adding the dehalogenating agent and the polymerization inhibitor to the first mixture to obtain a second mixture, stirring the second mixture and heating it to reflux; The mixed solution of allyl chloroformate and toluene is added dropwise to the second mixture in a reflux state. After the addition is completed, the reflux reaction is continued for 4 to 6 hours. After the reaction is completed, the small monomer with algaecide and antiseptic function is obtained by washing with water, drying, concentrating and crystallizing.

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