A kind of polyamino acid macromolecule and its preparation method and application

Abstract

The application discloses a kind of polyamino acid macromolecule and its preparation method and application, belong to functional polymer material technical field, polyamino acid macromolecule is obtained by unsaturated polyether macromonomer and p-chloromethyl styrene (p-CMS) occur polymerization reaction to obtain polymer intermediate (PTCS) after, then using polymer intermediate (PTCS) branch chain end chloromethyl group and amino acid class monomer occur grafting reaction, with similar polycarboxylic acid water reducing agent Molecular structure, structure contains carboxyl, amino and ethoxy group and benzene ring hydrophobic group, etc. Hydrophilic group, in aqueous solution with aggregate morphology exists further increases steric hindrance effect, so it shows excellent water reducing dispersion and anti mud sensitive performance.In addition, the production cost is significantly reduced by using commercially available unsaturated polyether macromonomer as the main raw material for this kind of polyamino acid macromolecule, so it has wide application prospect.

Description

Technical Field

[0001] This invention belongs to the field of functional polymer materials technology, and particularly relates to a polyamino acid-like macromolecule, its preparation method and application. Background Technology

[0002] Carboxylic acid copolymers are polymers copolymerized from unsaturated monomers containing carboxyl groups, unsaturated polyether macromonomers, and other functional monomers. When used in cement concrete, they can enhance the concrete's performance in terms of water reduction, slump retention, and mechanical properties, and are therefore known in the industry as high-performance polycarboxylate superplasticizers (PCEs). Compared to traditional lignin sulfonate, naphthalene sulfonate, melamine-formaldehyde condensate, and aminosulfonate-formaldehyde condensate superplasticizers, which have weaker water-reducing properties and involve large amounts of formaldehyde and environmental issues in their production processes, high-performance polycarboxylate superplasticizers (PCEs) are considered the third generation of high-performance superplasticizers due to their advantages such as low dosage, high water reduction rate, environmental friendliness, and strong adaptability. They have been widely used in engineering construction across various fields.

[0003] Although polycarboxylate superplasticizers possess significant water-reducing properties, their widespread application, extending from high-end to mid-to-low-end products, has revealed shortcomings and deficiencies. These primarily manifest in poor adaptability, sensitivity to aggregate mud content, and poor workability, posing challenges to their further widespread use. Currently, researchers both domestically and internationally have conducted extensive research on improving polycarboxylate superplasticizers, mainly focusing on enhancing their performance by introducing a third functional monomer. Invention patents CN201910140420.2 and CN202111094415.6 propose and prepare a series of polyamino acid macromolecules and their preparation methods. These not only exhibit excellent water-reducing and dispersing properties but also demonstrate excellent resistance to mud sensitivity. However, the high cost of raw materials for polyamino acid macromolecules hinders industrial application and promotion. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention proposes a novel polyamino acid macromolecule, its preparation method, and its applications. These macromolecules can be applied in fields such as building materials, waterproofing, gypsum board, and ceramic sanitary ware, significantly improving and enhancing the water-reducing dispersion and mud-sensitivity resistance of the cement concrete systems involved.

[0005] To achieve the above objectives, the present invention provides a polyamino acid-like macromolecule with the structural formula shown in (I):

[0006]

[0007] Where m = 1 to 4; n = 15 to 230; a = 1 to 3; x is an unsaturated polyether macromonomer; y is p-chloromethylstyrene; and the molar ratio of x to y is 1:5 to 50.

[0008] R1, R2 and R3 are all H or -CH3;

[0009] R4 is

[0010] This invention, starting from polymer molecular structure design, designs and prepares a novel polyamino acid-like macromolecule that can significantly improve and enhance the water-reducing, dispersion, and anti-mud sensitivity properties of the cement concrete system involved. In formula (I), the novel polyamino acid-like macromolecule is obtained by polymerizing an unsaturated polyether macromonomer with p-chloromethylstyrene (p-CMS) to obtain a polymer intermediate (PTCS), followed by grafting the chloromethyl groups at the branch ends of the PTCS with an amino acid monomer. In formula (I), R1, R2, and R3 are substituents of hydrogen (H) or methyl (-CH3), and R4 is the molecular backbone portion after the reaction of the amino acid monomer with the chloromethyl group. In formula (I), the m value of the methylene (-CH2-) repeating unit is 1 to 4, preferably 1, 2, 3, or 4; the n value of the ethoxy (-CH2CH2O-) repeating unit is 15 to 230.

[0011] A method for preparing the aforementioned polyamino acid macromolecule involves polymerizing an unsaturated polyether macromonomer with p-chloromethylstyrene (p-CMS) to obtain a polymer intermediate (PTCS), followed by grafting the chloromethyl groups at the branch ends of the polymer intermediate (PTCS) with an amino acid monomer.

[0012] Furthermore, in the method for preparing the polyamino acid macromolecule, the unsaturated polyether macromonomer has the structure of formula (Ⅲ):

[0013]

[0014] In formula (Ⅲ), the substituents R4, R2, and R3 in the unsaturated polyether macromonomer are hydrogen (H) or methyl (-CH3), the m value of the m repeating unit (-CH2-) is 1 to 4, n = 15 to 230, and R1, R2, and R3 are all H or -CH3.

[0015] In formula (Ⅲ), the molecular weight Mw of the unsaturated polyether macromonomer is 800 to 10000.

[0016] Furthermore, in the method for preparing the polyamino acid macromolecule, the molecular weight Mw of the unsaturated polyether macromonomer is 1000 to 6000.

[0017] Furthermore, in the method for preparing the polyamino acid macromolecule, the unsaturated polyether macromonomer is one of allyl polyethylene glycol ether (APEG), isobutylene polyethylene glycol ether (HPEG), isopentenyl polyethylene glycol ether (TPEG), and monoethylene-terminated diethylene glycol polyethylene glycol ether (GPEG).

[0018] Furthermore, in the method for preparing the polyamino acid macromolecule, the amino acid monomer is one of glycine, nitroglycerin, triacetic acid, aspartic acid, glutamic acid, and serine.

[0019] Furthermore, in the method for preparing the polyamino acid macromolecule, the molar ratio (x:y) of the unsaturated polyether macromonomer to p-chloromethylstyrene (p-CMS) is 1:5 to 50, preferably 1:5 to 30, and the molar ratio of the amino acid monomer to the chloromethyl group in the polymer intermediate (PTCS) is 1.0 to 1.2:1.

[0020] Furthermore, in the method for preparing the polyamino acid macromolecule, the polymer intermediate (PTCS) is prepared by polymerization of unsaturated polyether macromonomers with p-chloromethylstyrene (p-CMS), and has the structure of formula (II):

[0021]

[0022] Where m = 1 to 4; n = 15 to 230; R1, R2 and R3 are all H or -CH3; x:y (molar ratio) is 1:5 to 50.

[0023] Further, the preparation method of the polyamino acid macromolecule specifically includes the following steps: dissolving unsaturated polyether macromonomers and p-chloromethylstyrene (p-CMS) in tetrahydrofuran (THF), adding an azo initiator and heating to 70-75°C, refluxing and maintaining the temperature for 4-5 hours, then distilling to remove the tetrahydrofuran, adding amino acid monomers and deionized water, adjusting the pH of the system to 9-10 with sodium hydroxide, heating to 40-45°C, reacting for 3-4 hours and then stopping the reaction, cooling to room temperature to obtain the polyamino acid macromolecule.

[0024] Furthermore, in the preparation method of the polyamino acid macromolecule, the initiator is an azo initiator, specifically azobisisobutyronitrile (AIBN) or azobisisoheptanenitrile (ABVN), and the amount used is 0.5 to 1.5% of the total mass of the unsaturated polyether macromonomer and p-chloromethylstyrene (p-CMS).

[0025] Applications of the aforementioned polyamino acid macromolecules in building materials, waterproofing, gypsum board, and ceramic sanitary ware.

[0026] Application of the aforementioned polyamino acid macromolecules in cement concrete systems.

[0027] Compared with the prior art, the present invention has the following advantages and technical effects:

[0028] (1) The novel polyamino acid macromolecule involved in this invention uses unsaturated polyether macromonomers commonly used in the preparation of commercially available polycarboxylate superplasticizers as the main raw materials. By using a small amount of amino acid monomers, a novel polyamino acid macromolecule with a molecular structure similar to polycarboxylate superplasticizers is prepared, which significantly reduces the production cost and is very beneficial for industrial application and promotion. At the same time, when used in cement concrete systems, it exhibits excellent water-reducing, dispersing and anti-mud sensitivity properties.

[0029] (2) The novel polyamino acid macromolecules involved in this invention can be applied to building materials, waterproofing, gypsum board and ceramic sanitary ware by optimizing and controlling the ratio and composition of raw materials. Attached Figure Description

[0030] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0031] Figure 1 This invention provides a synthetic route for the polymeric amino acid macromolecules.

[0032] Figure 2 The fluidity properties of the paste prepared by the typical embodiment of the polyamino acid macromolecules under different montmorillonite dosages;

[0033] Figure 3 The fluidity properties of the slurry prepared as a typical example of a polyamino acid macromolecule under montmorillonite dosage over time. Detailed Implementation

[0034] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0035] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0036] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0037] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0038] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0039] The synthetic route for the polyamino acid macromolecules of this invention is shown below. Figure 1 .

[0040] The room temperature in this invention refers to 25±2℃.

[0041] Example 1

[0042] A polyamino acid-like macromolecule and its preparation method are as follows:

[0043] Weigh 2.4 kg of allyl polyethylene glycol ether (APEG, Mw≈2400) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then, distill to remove the tetrahydrofuran. Add 0.45 kg of glycine and 4 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h. Stop the reaction and cool to room temperature to obtain a polyamino acid macromolecule with a solid content of approximately 40%.

[0044] Example 2

[0045] A polyamino acid-like macromolecule and its preparation method are as follows:

[0046] Weigh 2.4 kg of isobutylene polyethylene glycol ether (HPEG, Mw≈2400) and 0.77 kg of p-chloromethylstyrene (p-CMS, 153) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then distill to remove the tetrahydrofuran. Add 0.45 kg of glycine and 5 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid-like macromolecule.

[0047] Example 3

[0048] A polyamino acid-like macromolecule and its preparation method are as follows:

[0049] Weigh 2.4 kg of isopentenyl polyethylene glycol ether (TPEG, Mw≈2400) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then distill to remove the tetrahydrofuran. Add 0.45 kg of glycine and 5 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid-like macromolecule.

[0050] Example 4

[0051] A polyamino acid-like macromolecule and its preparation method are as follows:

[0052] Weigh 3.0 kg of monoethylene-terminated diethylene glycol polyethylene glycol ether (GPEG, Mw≈3000) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.03 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 4–5 h. Then, distill to remove the tetrahydrofuran. Add 0.45 kg of glycine and 5 kg of deionized water, and adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid-like macromolecule.

[0053] Example 5

[0054] A polyamino acid-like macromolecule and its preparation method are as follows:

[0055] Weigh 2.4 kg of allyl polyethylene glycol ether (APEG, Mw≈2400) and 1.5 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.03 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then distill to remove the tetrahydrofuran. Add 0.9 kg of aminoacetic acid and 7 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h. Stop the reaction and cool to room temperature to obtain the polyamino acid macromolecule.

[0056] Example 6

[0057] A polyamino acid-like macromolecule and its preparation method are as follows:

[0058] Weigh 2.4 kg of isobutylene polyethylene glycol ether (HPEG, Mw≈2400) and 1.5 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.03 kg of AIBN initiator and heat to 70 °C. Reflux and maintain the temperature for 4 h. Then distill to remove the tetrahydrofuran. Add 0.9 kg of glycine and 4 kg of deionized water and adjust the pH of the system to 10 with sodium hydroxide. Heat to 45 °C and react for 3 h to stop the reaction. Cool to room temperature to obtain the polyamino acid macromolecule.

[0059] Example 7

[0060] A polyamino acid-like macromolecule and its preparation method are as follows:

[0061] Weigh 2.4 kg of isopentenyl polyethylene glycol ether (TPEG, Mw≈2400) and 1.5 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.03 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then, distill to remove the tetrahydrofuran solvent. Add 0.9 kg of aminoacetic acid and 7 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid-like macromolecule.

[0062] Example 8

[0063] A polyamino acid-like macromolecule and its preparation method are as follows:

[0064] Weigh 3.0 kg of monoethylene-terminated diethylene glycol polyethylene glycol ether (GPEG, Mw≈3000) and 1.5 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.036 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then, distill to remove the tetrahydrofuran. Add 0.9 kg of glycine and 7 kg of deionized water, and adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid-like macromolecule.

[0065] Example 9

[0066] A polyamino acid-like macromolecule and its preparation method are as follows:

[0067] Weigh 2.4 kg of allyl polyethylene glycol ether (APEG, Mw≈2400) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then, distill to remove the tetrahydrofuran solvent. Add 0.8 kg of aspartic acid and 6 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid macromolecule.

[0068] Example 10

[0069] A polyamino acid-like macromolecule and its preparation method are as follows:

[0070] Weigh 2.4 kg of isobutylene polyethylene glycol ether (HPEG, Mw≈2400) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 70 °C. Reflux and maintain the temperature for 5 h. Then distill to remove the tetrahydrofuran. Add 0.8 kg of aspartic acid and 6 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h. Stop the reaction and cool to room temperature to obtain the polyamino acid macromolecule.

[0071] Example 11

[0072] A polyamino acid-like macromolecule and its preparation method are as follows:

[0073] Weigh 2.4 kg of isopentenyl polyethylene glycol ether (TPEG, Mw≈2400) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then, distill to remove the tetrahydrofuran solvent. Add 0.8 kg of aspartic acid and 6 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid macromolecule.

[0074] Example 12

[0075] A polyamino acid-like macromolecule and its preparation method are as follows:

[0076] Weigh 3.0 kg of monoethylene-terminated diethylene glycol polyethylene glycol ether (GPEG, Mw≈3000) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.03 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then distill to remove the tetrahydrofuran. Add 0.8 kg of aspartic acid and 6 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h. After the reaction is stopped, cool to room temperature to obtain the polyamino acid macromolecule.

[0077] Example 13

[0078] A polyamino acid-like macromolecule and its preparation method are as follows:

[0079] Weigh 2.4 kg of isopentenyl polyethylene glycol ether (TPEG, Mw≈2400) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then, distill to remove the tetrahydrofuran. Add 0.8 kg of nitrogen diacetic acid and 6 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid-like macromolecule.

[0080] Example 14

[0081] A polyamino acid-like macromolecule and its preparation method are as follows:

[0082] Weigh 3.0 kg of monoethylene-terminated diethylene glycol polyethylene glycol ether (GPEG, Mw≈3000) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.03 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then distill to remove the tetrahydrofuran. Add 0.8 kg of N-diacetic acid and 7 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h. Stop the reaction and cool to room temperature to obtain the polyamino acid-like macromolecule.

[0083] Example 15

[0084] A polyamino acid-like macromolecule and its preparation method are as follows:

[0085] Weigh 2.4 kg of isopentenyl polyethylene glycol ether (TPEG, Mw≈2400) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then distill to remove the tetrahydrofuran. Add 0.88 kg of glutamic acid and 6 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h. Stop the reaction and cool to room temperature to obtain the polyamino acid macromolecule.

[0086] Example 16

[0087] A polyamino acid-like macromolecule and its preparation method are as follows:

[0088] Weigh 2.4 kg of allyl polyethylene glycol ether (APEG, Mw≈2400) and 3.0 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then, distill to remove the tetrahydrofuran. Add 1.8 kg of glycine and 11 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h to stop the reaction. Cool to room temperature to obtain the polyamino acid-like macromolecule.

[0089] Example 17

[0090] A polyamino acid-like macromolecule and its preparation method are as follows:

[0091] Weigh 6.0 kg of monoethylene-terminated diethylene glycol polyethylene glycol ether (GPEG, Mw≈6000) and 3.0 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.03 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then distill to remove the tetrahydrofuran. Add 1.8 kg of N-diacetic acid and 16 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h. After the reaction is stopped, cool to room temperature to obtain the polyamino acid-like macromolecule.

[0092] Example 18

[0093] A polyamino acid-like macromolecule and its preparation method are as follows:

[0094] Weigh 1.0 kg of allyl polyethylene glycol ether (APEG, Mw≈1000) and 0.77 kg of p-chloromethylstyrene (p-CMS) and dissolve them in tetrahydrofuran. Add 0.025 kg of AIBN initiator and heat to 75 °C. Reflux and maintain the temperature for 5 h. Then, distill to remove the tetrahydrofuran. Add 0.45 kg of glycine and 3 kg of deionized water. Adjust the pH of the system to 9 with sodium hydroxide. Heat to 40 °C and react for 4 h. Stop the reaction and cool to room temperature to obtain the polyamino acid macromolecule.

[0095] Performance testing

[0096] First, a commercially available polycarboxylate superplasticizer (PCE0) was selected as a comparative example to determine and characterize the aggregation morphology of the polyamino acid-like macromolecules (40% solids content) prepared in each embodiment of the present invention in aqueous solution. Second, the initial and over-time flowability of cement paste containing the polyamino acid-like macromolecules of the present invention was determined according to the national standard GB / T8076-2008 "Concrete Admixtures". Furthermore, the initial and over-time flowability properties of cement paste were also determined under conditions of adding different amounts of montmorillonite (0–5.0%, by mass ratio to cement) and a fixed amount of montmorillonite (2.0% by mass ratio to cement). Specific results are shown in Table 1. Figure 2 and Figure 3 As shown.

[0097] Table 1. Particle size and distribution of polyamino acid macromolecules prepared in typical examples and the fluidity of cement paste.

[0098]

[0099] The results show that, compared with the comparative examples, the polyamino acid-like macromolecules prepared in this invention all exhibit excellent water-reducing, dispersing, and anti-mud-sensitivity properties. This is because the novel polyamino acid-like macromolecules of this invention use unsaturated polyether macromonomers commonly used in the preparation of commercially available polycarboxylate superplasticizers as the main raw material, and the novel polyamino acid-like macromolecules prepared by supplementing with a small amount of amino acid monomers have a molecular structure similar to polycarboxylate superplasticizers. Furthermore, the novel polyamino acid-like macromolecules of this invention not only contain hydrophilic groups such as carboxyl, amino, and ethoxy groups, but also hydrophobic benzene ring repeating units. Therefore, they self-assemble in aqueous solution to form nano-aggregates with a hydrophobic benzene ring as the core and a hydrophilic chain segment as the shell. It is precisely this aggregate morphology of the novel polyamino acid-like macromolecules in aqueous solution that further increases the steric hindrance effect of the system, enabling it to not only exhibit excellent water-reducing and dispersing performance, but also, the introduction of nitrogen-containing functional groups into the amino acid functional monomers further inhibits the intercalation and adsorption consumption of clay, thus also enabling it to exhibit excellent anti-mud-sensitivity properties.

[0100] The novel polyamino acid-like macromolecule involved in this invention uses unsaturated polyether macromonomers commonly used in the preparation of commercially available polycarboxylate superplasticizers as the main raw material. By supplementing with a small amount of amino acid monomers, a novel polyamino acid-like macromolecule with a molecular structure similar to polycarboxylate superplasticizers is prepared, which significantly reduces the production cost and is very beneficial for industrial application and promotion, thus having broad application prospects.

[0101] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A polyamino acid-like macromolecule, characterized in that, The structural formula is shown in (I): Where m = 1 to 4; n = 15 to 230; the molar ratio of x to y is 1:5 to 50; R1, R2 and R3 are all H or CH3; R4 is , , , or .

2. A method for preparing the polyamino acid macromolecule of claim 1, characterized in that, The polymer intermediate is obtained by polymerizing unsaturated polyether macromonomers with p-chloromethylstyrene, and then grafting amino acid monomers with the chloromethyl groups at the end of the side chains of the polymer intermediate.

3. The method for preparing polyamino acid macromolecules according to claim 2, characterized in that, The molecular weight (Mw) of the unsaturated polyether macromonomer is 800–10000.

4. The method for preparing the polyamino acid macromolecule according to claim 3, characterized in that, The unsaturated polyether macromonomer is one of allyl polyethylene glycol ether, isobutylene polyethylene glycol ether, isopentenyl polyethylene glycol ether, and monoethylene-terminated diethylene glycol polyethylene glycol ether.

5. The method for preparing polyamino acid macromolecules according to claim 2, characterized in that, The amino acid monomer is one of glycine, NADI, aspartic acid, glutamic acid, and serine.

6. The method for preparing the polyamino acid macromolecule according to claim 2, characterized in that, The molar ratio of unsaturated polyether macromonomer to p-chloromethylstyrene is 1:5 to 50, and the molar ratio of amino acid monomer to chloromethyl groups in polymer intermediates is 1.0 to 1.2:

1.

7. The method for preparing polyamino acid macromolecules according to claim 2, characterized in that, Includes the following steps: Unsaturated polyether macromonomers and p-chloromethylstyrene were dissolved in tetrahydrofuran, an azo initiator was added, and the temperature was raised to 70-75°C. The mixture was refluxed and kept at this temperature for 4-5 hours. Then, the tetrahydrofuran was removed, and amino acid monomers and deionized water were added. The pH of the system was adjusted to 9-10 with sodium hydroxide, and the temperature was raised to 40-45°C. The reaction was stopped after 3-4 hours and cooled to room temperature to obtain polyamino acid-like macromolecules.

8. The application of the polyamino acid macromolecules described in claim 1 in the fields of building materials and waterproofing.

9. The application according to claim 8, characterized in that, The building materials sector includes gypsum board and ceramic sanitary ware.

10. The application of the polyamino acid macromolecules described in claim 1 in cement concrete systems.

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