Fabric waterproof agent without containing organic fluorine and preparation method of fabric waterproof agent

Abstract

The invention belongs to the field of organosilicon waterproofing, and discloses an organic fluorine-free fabric waterproofing agent and a preparation method thereof. The preparation method comprises the following steps: (1) carrying out hydrolytic condensation reaction on silicate ester, an epoxy silane coupling agent, tetramethyl dihydrodisiloxane and a long-chain alkyl silane coupling agent under an acidic condition to obtain a prepolymer I; (2) carrying out telomerization on a methyl siloxane ring body, a methyl vinyl siloxane ring body and pentamethyl-vinyl disiloxane in the presence of a catalyst to obtain end-side vinyl silicone oil; (3) carrying out addition reaction on the prepolymer I and end-side vinyl silicone oil under catalysis to obtain a prepolymer II; (4) reacting the prepolymer II with an amine compound to obtain a prepolymer III; and (5) reacting the prepolymer III with polyurethane to obtain the waterproof agent. According to the invention, a polyurethane material is combined on the basis of an organic silicon material, the non-fluorine fabric waterproof agent is obtained by using silicon teflon, and the prepared waterproof agent does not contain fluoride, has excellent waterproof performance, is green and environment-friendly, and is suitable for large-scale application.

Description

Technical Field

[0001] The present invention belongs to the field of silicone waterproofing, and more specifically relates to a fabric waterproofing agent without organic fluorine and a preparation method thereof. Background Art

[0002] At present, the waterproofing agents on the market are mainly perfluorooctyl (C8) organic fluorine waterproofing agents and perfluorohexyl (C6) organic fluorine waterproofing agents. In particular, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) substances may be generated during the production and use of C8 waterproofing agents, and perfluorohexanoic acid (PFHxA) and perfluorohexane sulfonic acid (PFHxS) may be generated during the production and use of C6 waterproofing agents. This trend indicates that the requirements for the environmental protection and safety of fabric waterproofing agents are increasing day by day, and the defluorination of waterproofing agents has become an irresistible trend.

[0003] However, the waterproofing agents prepared by the prior art have many problems. The technology described in Patent CN117700749A is long-chain alkyl silicone oil. Such silicone oil is linear silicone oil and can only adhere to the surface layer of the fabric, making it difficult to achieve a long-term waterproof effect. The technology described in Patent CN108997928A is a mixture of methyl silicone oil and methyl silicone resin. Although there will be a waterproof effect by virtue of the spatial structure of the silicone resin, it is still a linear methyl silicone oil system, and the waterproof effect is also greatly reduced. The technologies described in Patent CN115595795A and CN118165268A are silicone-modified acrylate. The final emulsification process is difficult, and precise control of the initiator is required for emulsion stability, which is not conducive to long-term product storage.

[0004] Therefore, how to provide a fabric waterproofing agent without organic fluorine and a preparation method thereof is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0005] In order to overcome the disadvantages and deficiencies in the prior art, the present invention provides a fabric waterproofing agent without organic fluorine and a preparation method thereof. Based on silicone materials, polyurethane materials are combined, and "replacing fluorine with silicone" to obtain a non-fluorinated fabric waterproofing agent. The manufactured waterproofing agent does not contain fluorides and has excellent waterproof performance.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A fabric waterproofing agent without organic fluorine, the chemical structure of the waterproofing agent is shown as follows:

[0008]

[0009] Wherein: R 1Selected from one of H, a polyether chain segment with a molecular weight of 1 - 2000, and a silanyloxy chain segment with a molecular weight of 120 - 1000; R 2 Selected from one of H, a polyether chain segment with a molecular weight of 1 - 2000, and a silanyloxy chain segment with a molecular weight of 120 - 1000; x is 8 - 130; y is 1 - 20; n is 2 - 16.

[0010] Preferably, R 1 Selected from H or a polyether chain segment with a molecular weight of 1 - 2000, and the EO / PO of the polyether chain segment is 1:1 - 2.

[0011] The present invention also provides a preparation method of the above - mentioned fabric waterproofing agent without organic fluorine, including the following steps:

[0012] (1) Add tetramethyldihydrodisiloxane, epoxy - group silane coupling agent, long - chain alkyl silane coupling agent, and silicate ester into a reaction vessel, then continue to add xylene and absolute ethanol to form a reaction system, stir evenly, dropwise add an acid solution, adjust the pH to 1 - 3, raise the temperature to 40 - 65 °C for hydrolysis and condensation reaction for 6 - 12 h. After the reaction, retain the oil phase, wash with water until neutral, filter to obtain a filtrate, and the solute content is 55 - 70%, and the solute is prepolymer I;

[0013] (2) Weigh methylsiloxane cyclics, methylvinylsiloxane cyclics, and pentamethyldivinyldisiloxane, and carry out telomerization reaction at 30 - 110 °C for 8 - 18 h under the action of a catalyst to obtain end - side vinyl silicone oil;

[0014] (3) Mix prepolymer I and end - side vinyl silicone oil, using xylene as a solvent, and carry out addition reaction at 120 - 160 °C for 0.5 - 1.5 h under the action of a catalyst. After the reaction, keep the reaction temperature and remove xylene under negative pressure to obtain a light - yellow liquid, which is prepolymer II;

[0015] (4) Mix prepolymer II and an amine compound, using isopropanol as a solvent, and carry out reaction at 30 - 90 °C for 2 - 6 h. After the reaction, keep the reaction temperature and remove isopropanol under negative pressure to obtain prepolymer III;

[0016] (5) Mix prepolymer III and polyurethane, and carry out reaction at 30 - 110 °C for 2 - 10 h to obtain the waterproofing agent.

[0017] Preferably, in step (1):

[0018] The molar ratio of the tetramethyldihydrodisiloxane, epoxy - group silane coupling agent, long - chain alkyl silane coupling agent, and silicate ester is 0.6 - 0.9:0.4 - 0.7:0.3 - 0.6:0.5 - 1.8;

[0019] The xylene accounts for 30 - 50% of the total volume of the reaction system, and the absolute ethanol accounts for 5 - 10% of the total volume of the reaction system;

[0020] The mass fraction of the acid solution is 0.8 - 2%.

[0021] Preferably, in step (1):

[0022] The epoxy group silane coupling agent is selected from one of KH-560, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-3-glycidyletheroxypropyltriethoxysilane, and 3-glycidyletheroxypropylmethyldimethoxysilane;

[0023] The long-chain alkyl silane coupling agent is selected from one of n-dodecyltrimethoxysilane, n-hexyltriethoxysilane, n-octyltriethoxysilane, n-hexadecyltrimethoxysilane, and n-octadecyltrimethoxysilane;

[0024] The silicate ester is selected from one of methyl silicate, ethyl silicate, propyl silicate, butyl silicate, and ethyl silicate oligomer Si40;

[0025] The acid is selected from one of hydrochloric acid, sulfuric acid, and trifluoromethylsulfonic acid.

[0026] Preferably, in step (2):

[0027] The methyl siloxane cyclic body is selected from one of tetramethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, decamethylcyclopentasiloxane, and octamethylcyclotetrasiloxane;

[0028] The methyl vinyl siloxane cyclic body is selected from one of tetramethyltetravinyltetrasiloxane, pentamethylpentavinylcyclopentasiloxane, and trimethyltrivinylcyclotrisiloxane;

[0029] The catalyst is selected from one of tetramethylammonium hydroxide, acidic activated clay, trifluoromethylsulfonic acid, concentrated sulfuric acid, and potassium hydroxide.

[0030] Preferably, in step (2), the mass ratio of the methyl siloxane cyclic body, the methyl vinyl siloxane cyclic body, and pentamethylvinyl disiloxane is 200 - 2000:30 - 150:10 - 30;

[0031] The molecular weight of the terminal vinyl silicone oil is 500 - 10000.

[0032] Preferably, in step (3):

[0033] The molar ratio of the active hydrogen in the prepolymer I to the vinyl group in the terminal vinyl silicone oil is 1:1.2 - 1.4;

[0034] The catalyst is selected from one of Kaster catalyst and chloroplatinic acid hexahydrate, and the dosage of the catalyst is 1000 - 5000 ppm;

[0035] Preferably, in step (4):

[0036] The isopropanol accounts for 40 - 50% of the total volume of the reaction system;

[0037] The molar ratio of the epoxy group in prepolymer II to the amino group in the amine compound is 1:1.3 - 2.3;

[0038] The amine compound is selected from one of amino silane coupling agents and polyetheramines;

[0039] The amino silane coupling agent is selected from one of KH550, γ - piperazinylpropylmethyldimethoxysilane, and N - cyclohexyl - γ - aminopropylmethyldimethoxysilane;

[0040] The polyetheramine is selected from one of diamines and triamines.

[0041] Preferably, in step (4):

[0042] The structural formula of the diamine is as follows:

[0043]

[0044] Wherein, x 1 +y 1 +z 1 = a natural number from 1 to 60;

[0045] The structural formula of the triamine is as follows:

[0046]

[0047] Wherein, x 2 +y 2 +z 2 = a natural number from 5 to 6.

[0048] Preferably, in step (5):

[0049] The mass ratio of prepolymer III to polyurethane is 100 - 400:10 - 35;

[0050] The polyurethane is selected from one of hexamethylene diisocyanate, isophorone diisocyanate, and diphenylmethane diisocyanate.

[0051] The synthesis route of the waterproof agent of the present invention is as follows:

[0052] (1) A prepolymer I is obtained after the hydrolysis and condensation reaction of silicate, epoxy group-containing silane coupling agent, tetramethyldihydrodisiloxane, and long-chain alkyl silane coupling agent under acidic conditions;

[0053]

[0054] (2) An end- and side-vinyl silicone oil is obtained after telomerization of methyl siloxane cyclic body, methyl vinyl siloxane cyclic body, and pentamethyl-1-vinyl disiloxane with a catalyst;

[0055]

[0056] (3) A prepolymer II is obtained by the addition reaction of prepolymer I and end- and side-vinyl silicone oil under catalysis;

[0057]

[0058] (4) A prepolymer III is obtained by the reaction of prepolymer II with an amine compound;

[0059]

[0060] (5) A product waterproofing agent is obtained by the reaction of prepolymer III with polyurethane;

[0061]

[0062] As can be seen from the above technical solutions, compared with the prior art, the present invention provides a fabric waterproofing agent without organic fluorine and its preparation method, which has the following beneficial effects:

[0063] 1. Based on the silicone material and combined with the polyurethane material, a non-fluorine fabric waterproofing agent is obtained by "replacing fluorine with silicon". The manufactured waterproofing agent does not contain fluorides, has excellent waterproof performance, is green and environmentally friendly, and is suitable for large-scale applications. The monomers containing alkoxy groups in step (1) can form a network structure macromolecule after hydrolysis and polycondensation, and the long-chain alkyl group has a waterproof effect. The combination of the two can improve the waterproof ability. Tetramethyldihydrodisiloxane is used as a capping agent, and its dosage can adjust the molecular size. The introduced reactive functional groups such as epoxy and active hydrogen lay the foundation for subsequent reactions. The key lies in finding the ratio between various reactants. In step (2), vinyl silicone oil is synthesized, and the vinyl groups are distributed at the end and side positions, increasing the reaction points. In step (3), a Kast catalyst is used to make the addition of hydrogen and double bonds, resulting in an increase in the molecular weight of the product, thereby further improving the waterproof effect. Step (4) is to lay the foundation for the polyurethane reaction in step (5). Adding polyurethane can make the waterproofing agent more persistent.

[0064] 2. The waterproofing agent prepared by the present invention, after being emulsified by a non-ionic surfactant, obtains a waterproofing agent emulsion, whose waterproof performance has been comparable to that of fluorine-containing waterproofing agents and has exceeded that of commercially available silicone-based waterproofing agents. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to the provided drawings.

[0066] Figure 1 It is the process flow chart of the present invention.

[0067] Figure 2 They are the effect diagrams of different water repellency levels. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0068] The following will clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0069] Example 1

[0070] A fabric waterproofing agent without organofluorine, the chemical structure of the waterproofing agent is shown as follows:

[0071]

[0072] Among them: x = 8.4, y = 1.32, n = 3.

[0073] The preparation method of the above fabric waterproofing agent without organofluorine includes the following steps:

[0074] (1) Tetramethyldihydrodisiloxane: KH-560: n-dodecyltrimethoxysilane: tetramethoxysilane are added to a flask according to a molar ratio of 0.6:0.6:0.3:1.3. Then xylene and absolute ethanol are further added to form a reaction system, where xylene accounts for 40% of the total volume of the reaction system and absolute ethanol accounts for 8%. After stirring evenly, a 1.0% hydrochloric acid aqueous solution is added dropwise to adjust the pH to 2, and the temperature is raised to 45 °C for hydrolysis and condensation reaction for 12 h. After the reaction, the oil phase is retained, washed with water until neutral, and filtered to obtain a filtrate with a solute content of 59%. The solute is prepolymer I;

[0075] (2) Weigh octamethylcyclotetrasiloxane, tetramethyltetravinyltetrasiloxane, and pentamethylethenyldisiloxane in a mass ratio of 430:80:12 to synthesize terminal vinyl silicone oil. The catalyst is tetramethylammonium hydroxide, the reaction temperature is 110 °C, and the reaction time is 10 h. The molecular weight of the obtained terminal vinyl silicone oil is 630;

[0076] (3) Add prepolymer I and terminal vinyl silicone oil to a flask according to a molar ratio of active hydrogen to vinyl of 1:1.2. The solvent is xylene, and 3000 ppm of Karstedt catalyst is used. The reaction temperature is 140 °C, and the reaction lasts for 30 min. After the reaction, keep the reaction temperature and evacuate the solvent under negative pressure to obtain a light yellow liquid substance, which is prepolymer II;

[0077] (4) React polyetheramine ED600 with prepolymer II. The molar ratio of amino group to epoxy group is 1.4:1. Isopropanol is used as the solvent in the reaction system, and the solvent accounts for 40% of the total volume of the reaction system. The reaction temperature is 80 °C, and there should be obvious reflux of isopropanol during the reaction. The reaction time is 6 h. After the reaction, keep the reaction temperature and evacuate isopropanol under negative pressure to obtain prepolymer III;

[0078] (5) Add prepolymer III and hexamethylene diisocyanate in a weight ratio of 100:20 to a flask. The reaction temperature is 70 °C, and the reaction time is 6 h to obtain the waterproofing agent product.

[0079] Example 2

[0080] A fabric waterproofing agent without organofluorine, the chemical structure of the waterproofing agent is as follows:

[0081]

[0082] Among them: x = 54, y = 1, n = 3.

[0083] A preparation method of a fabric waterproofing agent without organofluorine, comprising the following steps:

[0084] (1) Add tetramethyldihydrodisiloxane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: n-hexyltriethoxysilane: tetraethyl orthosilicate in a molar ratio of 0.7:0.7:0.5:0.8 to a flask, and then add xylene and absolute ethanol to form a reaction system. Xylene accounts for 45% of the total volume of the reaction system, and absolute ethanol accounts for 8% of the total volume of the reaction system. After stirring evenly, add a 0.8% sulfuric acid aqueous solution to adjust the pH to 2, heat up to 58 °C, and react for 12 h. After the reaction, retain the oil phase, wash it with water until neutral, filter it to obtain a filtrate, and the solute content is 59%. The solute is prepolymer I;

[0085] (2) Weigh hexamethylcyclotrisiloxane, pentamethylpentavinylcyclopentasiloxane, and pentamethyldivinyldisiloxane with a mass ratio of 200:80:10 to synthesize a terminal and side vinyl silicone oil. The catalyst is acidic activated clay, the reaction temperature is 80 °C, the reaction time is 8 h, and after filtration, the molecular weight of the terminal and side vinyl silicone oil obtained is 4100;

[0086] (3) Add prepolymer I and terminal and side vinyl silicone oil to the flask according to a molar ratio of active hydrogen to vinyl of 1:1.3. The solvent is xylene, and 1000 ppm of Karstedt catalyst is used. The reaction temperature is 130 °C, and the reaction is carried out for 1.5 h. While maintaining the reaction temperature, the solvent is removed by negative pressure to obtain a light yellow liquid substance, which is prepolymer II;

[0087] (4) React γ-piperazinylpropylmethyldimethoxysilane with prepolymer II. The molar ratio of amino group to epoxy group is 2.3:1. Isopropanol is used as the solvent in the reaction system, and the solvent accounts for 50% of the total volume of the reaction system. The reaction temperature is 60 °C, and there should be obvious reflux of isopropanol during the reaction. The reaction time is 2.5 h. After the reaction, isopropanol is removed by negative pressure while maintaining the reaction temperature to obtain prepolymer III;

[0088] (5) Add prepolymer III and isophorone diisocyanate in a weight ratio of 200:10 to the flask, the reaction temperature is 70 °C, and the reaction time is 8 h to obtain a waterproofing agent product.

[0089] Example 3

[0090] A fabric waterproofing agent without organofluorine, the chemical structure of the waterproofing agent is as follows:

[0091]

[0092] Among them: x = 38.5, y = 3.51, n = 5.

[0093] The preparation method of the above fabric waterproofing agent without organofluorine includes the following steps:

[0094] (1) Add tetramethyldihydrodisiloxane: 3-3-glycidyletheroxypropyltriethoxysilane: n-octyltriethoxysilane: tetrapropyl orthosilicate in a molar ratio of 0.9:0.7:0.5:1.1 to the flask, and then add xylene and absolute ethanol to obtain a reaction system. Xylene accounts for 40% of the total volume of the reaction system, and absolute ethanol accounts for 10% of the total volume of the reaction system. After stirring evenly, add an aqueous solution of 1.5% trifluoromethanesulfonic acid to adjust the pH to 3, heat up to 65 °C, and react for 6 h. After the reaction, retain the oil phase, wash it with water until neutral, filter, and obtain a filtrate with a solute content of 67%. The solute is prepolymer I;

[0095] (2) Weigh decamethylcyclopentasiloxane, trimethyltrivinylcyclotrisiloxane, and pentamethylethenyldisiloxane in a mass ratio of 400:60:25 to synthesize terminal vinyl silicone oil. Using trifluoromethanesulfonic acid as a catalyst, the reaction temperature is 30 °C, the reaction time is 18 h, and after washing with water until neutral, the molecular weight of the terminal vinyl silicone oil obtained is 3500;

[0096] (3) Add prepolymer I and terminal vinyl silicone oil to a flask according to a molar ratio of active hydrogen to vinyl of 1:1.4. The reaction solvent is xylene, and the catalyst is 2000 ppm chloroplatinic acid hexahydrate. The reaction temperature is 160 °C, and the reaction is carried out for 1 h. While maintaining the reaction temperature, the solvent is removed by negative pressure to obtain a light yellow liquid substance, which is prepolymer II;

[0097] (4) React γ-piperazinylpropylmethyldimethoxysilane with prepolymer II. The molar ratio of amino group to epoxy group is 1.6:1. Isopropanol is used as the solvent in the reaction system, and the solvent accounts for 40% of the total volume. The reaction temperature is 90 °C, and there should be obvious reflux of isopropanol during the reaction. The reaction time is 3 h. After the reaction ends, isopropanol is removed by negative pressure while maintaining the reaction temperature to obtain prepolymer III;

[0098] (5) Add prepolymer III and isophorone diisocyanate in a weight ratio of 400:30 to a flask. The reaction temperature is 80 °C, and the reaction time is 8 h to obtain the waterproofing agent product.

[0099] Example 4

[0100] A fabric waterproofing agent without organic fluorine, the chemical structure of the waterproofing agent is shown as follows:

[0101]

[0102] The preparation method of the above fabric waterproofing agent without organic fluorine includes the following steps:

[0103] (1) Add tetramethyldihydrodisiloxane: 3-glycidoxypropylmethyldimethoxysilane: n-hexadecyltrimethoxysilane: tetrabutyl orthosilicate = 0.68:0.4:0.6:0.5 to a flask according to the molar ratio. Then add xylene and absolute ethanol to form a reaction system. Xylene accounts for 40% of the total volume of the reaction system, and absolute ethanol accounts for 10% of the total volume of the reaction system. After stirring evenly, add an aqueous solution of trifluoromethanesulfonic acid with a mass fraction of 0.8% to adjust the pH to 3, and heat up to 40 °C. React for 12 h. After the reaction ends, retain the oil phase, wash with water until neutral, filter, and obtain a filtrate with a solute content of 60%. The solute is prepolymer I;

[0104] (2) Weigh octamethylcyclotetrasiloxane, tetramethyltetravinylcyclotetrasiloxane, and pentamethylethenyldisiloxane in a mass ratio of 1000:90:20 to synthesize terminal vinyl silicone oil. Concentrated sulfuric acid is used as the catalyst, the reaction temperature is 60 °C, the reaction time is 12 h, and it is washed with water until neutral. The molecular weight of the obtained terminal vinyl silicone oil is 10,000;

[0105] (3) Add prepolymer I and terminal vinyl silicone oil to the flask according to a molar ratio of active hydrogen to vinyl of 1:1.4. The solvent is xylene, and 5000 ppm of Karstedt catalyst is used. The reaction temperature is 140 °C, and the reaction is carried out for 1 h. While maintaining the reaction temperature, the solvent is removed under negative pressure to obtain a light yellow liquid substance, which is prepolymer II;

[0106] (4) React γ-piperazinylpropylmethyldimethoxysilane with prepolymer II. The molar ratio of amino group to epoxy group is 2:1. Isopropanol is used as the solvent in the reaction system, and the solvent accounts for 40% of the total volume. The reaction temperature is 70 °C, and there should be obvious reflux of isopropanol during the reaction. The reaction time is 3 h. After the reaction is completed, isopropanol is removed under negative pressure while maintaining the reaction temperature to obtain prepolymer III;

[0107] (5) Add prepolymer III and isophorone diisocyanate in a weight ratio of 300:35 to the flask. The reaction temperature is 110 °C, and the reaction time is 10 h to obtain the waterproofing agent product.

[0108] Example 5

[0109] A fabric waterproofing agent without organic fluorine, the chemical structure of the waterproofing agent is shown as follows:

[0110]

[0111] Where: x = 46.72, y = 12.57, n = 15.

[0112] The preparation method of the above-mentioned fabric waterproofing agent without organic fluorine includes the following steps:

[0113] (1) Add tetramethyldihydrodisiloxane: 3-glycidoxypropylmethyldimethoxysilane: n-octadecyltrimethoxysilane: ethyl silicate oligomer Si40 in a molar ratio of 0.75:0.4:0.6:1.8 to the flask, and then add xylene and absolute ethanol to form a reaction system. Xylene accounts for 50% of the total volume of the reaction system, and absolute ethanol accounts for 8% of the total volume of the reaction system. After stirring evenly, add a 2.0% hydrochloric acid aqueous solution by mass fraction to adjust the pH to 2.5, and heat up to 45 °C. After the reaction for 12 h, the oil phase is retained, washed with water until neutral, filtered, and the filtrate is obtained. The solute content is 55%, and the solute is prepolymer I;

[0114] (2) Weigh octamethylcyclotetrasiloxane, trimethyltrivinylcyclotrisiloxane, and pentamethylethenyl disiloxane in a mass ratio of 200:60:10 to synthesize terminal vinyl silicone oil. Potassium hydroxide is used as a catalyst, the reaction temperature is 110 °C, the reaction time is 8 h, and the molecular weight of the obtained terminal vinyl silicone oil is 4,700;

[0115] (3) Add prepolymer I and terminal vinyl silicone oil to a flask according to a molar ratio of active hydrogen to vinyl of 1:1.3. The reaction solvent is xylene, 1,500 ppm of Karstedt catalyst is used, the reaction temperature is 140 °C, and the reaction is carried out for 1 h. While maintaining the reaction temperature, the solvent is removed by negative pressure to obtain a light yellow liquid substance, namely prepolymer II;

[0116] (4) React N-cyclohexyl-γ-aminopropylmethyldimethoxysilane with prepolymer II. The molar ratio of amino group to epoxy group is 1.3:1. Isopropanol is used as the solvent in the reaction system, and the solvent accounts for 40% of the total volume. The reaction temperature is 70 °C, and there should be obvious reflux of isopropanol during the reaction. The reaction time is 2.5 h. After the reaction, isopropanol is removed by negative pressure while maintaining the reaction temperature to obtain prepolymer III;

[0117] (5) The weight ratio of prepolymer III to diphenylmethane diisocyanate is 200:15. Add them to a flask, the reaction temperature is 70 °C, and the reaction time is 8 h to obtain a waterproofing agent product.

[0118] Add the waterproofing agent products of each example to non-ionic emulsifiers TO-3 and TO-8 with different ratios. The HLB value of the emulsifier is 8.0 - 10.0, and emulsification is carried out simultaneously to obtain an emulsion waterproofing agent. The addition amount of the emulsifier is 6% of the emulsion waterproofing agent. The specific ratios and HLB values of the emulsifier are shown in Table 1.

[0119] Table 1

[0120] Example 1 Example 2 Example 3 Example 4 Example 5 Mass ratio of TO-3 to emulsifier 100％ 90％ 80％ 70％ 60％ Mass ratio of TO-8 to emulsifier 0 10％ 20％ 30％ 40％ HLB value of emulsifier 8 8.48 8.96 9.44 9.92

[0121] Compare the emulsion waterproofing agent with commercially available waterproofing agents. Among them, the commercially available fluorine-free emulsion waterproofing agent is purchased from Ningbo Runhe High-Tech Materials Technology Co., Ltd., RH-NB-SF16 polyurethane-modified acrylate fluorine-free waterproofing agent; the commercially available fluorinated emulsion waterproofing agent is purchased from Suzhou Zhiyuan Xinke Chemical Co., Ltd., FE-8610 octacarbon super waterproof finishing agent.

[0122] The test method refers to GB / T4745-2012 "Testing and Evaluation of Waterproof Performance of Textiles (Spray Test)". Select polyester fabrics for sample cutting; the contact angle measurement is carried out using a contact angle analyzer to measure the contact angle between the fabric and water. The amount of water is 5 μL, and the reading is taken 60 seconds after the water droplet contacts the fabric. Table 2 shows the waterproof performance evaluation criteria for different spray grades, and Table 3 shows the evaluation results. Figure 2Effect diagrams for different water-retaining levels.

[0123] Table 2

[0124]

[0125]

[0126] Table 3

[0127]

[0128] It can be seen that on the basis of silicone resin, the present invention grafts polyurethane material to form a brand-new silicon-carbon waterproof agent, and its waterproof performance is equivalent to that of fluorine-containing waterproof agents and is superior to commercially available silicone-based waterproof agents.

[0129] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A fabric waterproofing agent free of organic fluorine, characterized in that: The chemical structure of the waterproofing agent is shown below: Wherein: R1 is selected from one of H, a polyether segment with a molecular weight of 1-2000, and a siloxy segment with a molecular weight of 120-1000; R2 is selected from one of H, a polyether segment with a molecular weight of 1-2000, and a siloxy segment with a molecular weight of 120-1000; x is 8-130; y is 1-20; and n is 2-16.

2. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 1, characterized in that: The following steps are involved: (1) adding tetramethyldihydrogendisiloxane, epoxysilane coupling agent, long-chain alkylsilane coupling agent and silicate into a reaction vessel, and continuing to add xylene and anhydrous ethanol to form a reaction system, stirring evenly, dropping an acid solution, adjusting the pH to 1-3, heating to 40-65° C. to carry out a hydrolysis condensation reaction for 6-12 hours, retaining an oil phase after the reaction, washing with water until neutral, filtering and obtaining a filtrate having a solute content of 55-70%, wherein the solute is prepolymer I; (2) weighing methylsiloxane ring body, methylvinylsiloxane ring body, and pentamethylvinyldisiloxane, and carrying out a telomerization reaction at 30-110° C. for 8-18 hours under the action of a catalyst to obtain a terminal vinyl silicone oil; (3) Prepolymer I and end-side vinyl silicone oil are mixed, wherein xylene is used as a solvent, and an addition reaction is carried out at 120-160° C. for 0.5-1.5 h under the action of a catalyst. After the reaction is completed, the reaction temperature is maintained and the xylene is removed under negative pressure to obtain a light yellow liquid, i.e., prepolymer II; (4) Prepolymer II and an amine compound are mixed, and isopropanol is used as a solvent, and the reaction is carried out at 30-90° C. for 2-6 hours. After the reaction is completed, the isopropanol is removed by maintaining the reaction temperature under negative pressure to obtain prepolymer III; (5) Prepolymer III and polyurethane are mixed and reacted at 30-110° C. for 2-10 hours to obtain a waterproofing agent.

3. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 2, characterized in that: In step (1): The molar ratio of tetramethyldihydrogendisiloxane, epoxysilane coupling agent, long-chain alkylsilane coupling agent and silicate is 0.6-0.9: 0.4-0.7: 0.3-0.6: 0.5-1.

8.

4. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 2, characterized in that: In step (1): The epoxysilane coupling agent is selected from one of KH-560, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-3-glycidyloxypropyltriethoxysilane, and 3-glycidyloxypropylmethyldimethoxysilane; The long-chain alkyl silane coupling agent is selected from one of n-dodecyltrimethoxysilane, n-hexyltriethoxysilane, n-octyltriethoxysilane, n-hexadecyltrimethoxysilane and n-octadecyltrimethoxysilane; The silicate is selected from one of methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, butyl orthosilicate, and ethyl silicate oligomer Si40.

5. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 2, characterized in that: In step (2): The methylsiloxane ring body is selected from one of tetramethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, decamethylcyclopentasiloxane and octamethylcyclotetrasiloxane; The methylvinylsiloxane ring body is selected from one of tetramethyltetravinyltetrasiloxane, pentamethylpentavinylcyclopentasiloxane and trimethyltrivinylcyclotrisiloxane; The catalyst is selected from tetramethylammonium hydroxide, acidic activated clay, trifluoromethanesulfonic acid, concentrated sulfuric acid and potassium hydroxide.

6. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 2, characterized in that: The mass ratio of the methylsiloxane ring body, the methylvinylsiloxane ring body and the pentamethylmonovinyldisiloxane in step (2) is 200-2000:30-150:10-30.

7. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 2, characterized in that: In step (3): The molar ratio of active hydrogen in the prepolymer I to vinyl in the terminal vinyl silicone oil is 1:1.2-1.4; The catalyst is selected from one of a Custer catalyst and chloroplatinic acid hexahydrate, and the catalyst dosage is 1000-5000ppm.

8. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 2, characterized in that: In step (4): The molar ratio of the epoxy group in the prepolymer II to the amino group in the amine compound is 1:1.3-2.3; The amine compound is selected from one of aminosilane coupling agents and polyetheramines; The aminosilane coupling agent is selected from one of KH550, γ-piperazinepropylmethyldimethoxysilane, and N-cyclohexyl-γ-aminopropylmethyldimethoxysilane; The polyetheramine is selected from diamine and triamine.

9. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 8, characterized in that: In step (4): The diamine structural formula is shown below: Among them, x1+y1+z1=natural numbers from 1 to 60; The structural formula of the triamine is shown below: Among them, x2+y2+z2=5~6 is a natural number.

10. The method for preparing a fabric waterproofing agent free of organic fluorine according to claim 2, characterized in that: In step (5): The mass ratio of the prepolymer III to the polyurethane is 100-400:10-35; The polyurethane is selected from one of hexamethylene diisocyanate, isophorone diisocyanate and diphenylmethane diisocyanate.

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