An acid and alkali resistant organosilicon surfactant and its preparation method
By preparing acid and alkali resistant organosilicon surfactants, the problem of easy hydrolysis of organosilicon surfactants in acid and alkali environments was solved, achieving stability and industrial production under acid and alkali environments, and reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- 浙江润禾有机硅新材料有限公司
- Filing Date
- 2022-12-19
- Publication Date
- 2026-05-26
AI Technical Summary
Existing organosilicon surfactants are easily hydrolyzed in acidic or alkaline environments, resulting in the loss of their surface activity. Furthermore, the raw materials are not readily available and the processes are cumbersome, which is not conducive to industrial applications.
An acid- and alkali-resistant organosilicon surfactant was prepared by hydrosilylation reaction of hydrogen-containing polysiloxane and unsaturated polyether in the presence of a catalyst. The process was simplified by increasing the Si-CH3 density and using readily available raw materials, and a hydrophilic-hydrophobic structure was formed.
It improves the stability of silicone surfactants in acidic and alkaline environments, extends shelf life, reduces production costs, and facilitates industrial application.
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Figure CN116199886B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of organosilicon surfactant technology, and more particularly to an acid and alkali resistant organosilicon surfactant and its preparation method. Background Technology
[0002] Organosilicon surfactants are widely used in textiles, coatings, daily chemicals, agrochemicals, and other fields due to their extremely low surface tension. Among them, trisiloxane-based organosilicon surfactants exhibit the most outstanding surface activity, with surface tensions as low as 21 mN / m. They possess excellent wetting, spreading, and penetrating properties, making them widely used in agrochemicals, daily chemicals, coatings, and inks. However, trisiloxane surfactants are highly susceptible to hydrolysis. Although the Si-O bond energy (452 kJ / mol) provides excellent thermal stability, the relatively long Si-O bond length allows for partial ionization, making them prone to hydrolysis and breakage by protic acids, protic bases, water, or alcohols. After breakage, the resulting organosilicon surfactant loses its excellent surface activity, leading to a decline in the quality of formulated products.
[0003] Chinese invention patent CN103585926B provides an acid and alkali resistant polyether modified trisiloxane surfactant. It mainly modifies the polyether by replacing the conventional allyl group with an unsaturated acyl group and connecting the unsaturated acyl group and the polyether segment through ether bonds or N. Although this method can improve the acid and alkali resistance to a certain extent, the special structure of the unsaturated acyl polyether is relatively complicated and rare in the market, which is not conducive to industrialization. Moreover, its acid and alkali resistance is short-lived, about one month at pH 3-9, while the shelf life is 24 months under the conventional application conditions of pH 3-12, which is difficult to meet the requirements of long-term stability of formulations.
[0004] US patents US2007088091A1 and US2007184005A1 disclose hydrolysis-resistant organosilicon surfactants, which mainly increase the difficulty for water molecules to attack silicon atoms by attaching larger alkyl groups (relative to methyl groups) to silicon atoms in the hydrophobic chain. However, the siloxane, one of the raw materials for synthesizing such hydrolysis-resistant organosilicon surfactants, has a special structure. Only expensive reagent-grade siloxanes are available, and there are no industrially available raw materials. The high cost and scarcity of these raw materials hinder industrialization. Summary of the Invention
[0005] To address the problems of existing technologies, such as the scarcity of raw materials, cumbersome processes, difficulty in industrialization, and insufficient acid and alkali resistance, this invention aims to provide an acid and alkali resistant organosilicon surfactant. This surfactant exhibits excellent acid and alkali resistance, readily available raw materials, simple processing, environmental friendliness, and ease of industrialization.
[0006] To achieve the above objectives, the present invention adopts the following technical solution:
[0007] An acid- and alkali-resistant silicone surfactant, comprising a hydrophilic portion and a hydrophobic portion; the hydrophilic portion is provided by a polyether, and its structure is shown below:
[0008]
[0009] R is the saturated hydrocarbon group corresponding to a straight-chain or branched unsaturated olefin of C2-C5 after addition, a = 0-20, b = 0-20, and a and b are both positive integers;
[0010] The hydrophobic portion is provided by a polysiloxane with an MDT' or MDD'T structure, where M is a monofunctional (CH3)Si chain segment. 1 / 2 D is a difunctional chain segment (CH3)2Si 2 / 2 D' represents a difunctional repeating unit (HCH3)Si 2 / 2 T represents the trifunctional chain segment HSiO 3 / 2 T' is a trifunctional chain segment HSiO 3 / 2 The structure is as follows:
[0011]
[0012] Where P and Q are either H or CH3, and are not both H or CH3 at the same time, m = 1-20, n = 0-20, o = 0-20, and m, n, and o are all positive integers.
[0013] As a specific implementation method, when P is H and Q is CH3, the structure of the acid and alkali resistant organosilicon surfactant is as follows:
[0014]
[0015] Where m = 1-20, n = 0-20, a = 0-20, b = 0-20, and R is a C2-C5 straight-chain or straight-chain saturated hydrocarbon group; preferably m = 1-10, n = 0-10; more preferably m = 1-5, n = 0-5.
[0016] As a specific implementation method, when Q is H and P is CH3, the structure of the acid and alkali resistant organosilicon surfactant is as follows:
[0017]
[0018] Where m = 1-20, n = 0-20, o = 1-20, a = 0-20, b = 0-20, and R is a C2-C5 straight-chain or straight-chain saturated hydrocarbon group; preferably m = 1-10, n = 0-10, o = 1-10; more preferably m = 1-5, n = 0-5, o = 1-5.
[0019] Furthermore, the present invention also discloses a method for preparing an acid and alkali resistant organosilicon surfactant, the method comprising the following steps: a hydrogen-containing polysiloxane and an unsaturated polyether undergo a hydrosilylation reaction in the presence of a catalyst, wherein the molar ratio of the hydrogen-containing polysiloxane to the di-terminated alkenyl polyether is (0.8-2):(0.8-2), and the reaction is carried out under nitrogen protection at 60-130°C for 2-10 hours by stirring to obtain an acid and alkali resistant organosilicon surfactant;
[0020] The structural formula of hydrogen-containing polysiloxanes is as follows:
[0021]
[0022] The structural formula of unsaturated polyether is as follows:
[0023]
[0024] Preferably, the catalyst is a noble metal catalyst, specifically a platinum, rhodium, or cesium catalyst, and more preferably a chloroplatinic acid or platinum-vinyldisilazane complex, used in an amount of 1-50 ppm of the total amount.
[0025] As a preferred option, the hydrogen-containing polysiloxane is an MDT' structured hydrogen-containing polysiloxane, which is prepared by mixing MM or MDM, polydimethyl mixed cyclosiloxane (DMC) and trialkoxy hydrogen-containing silane in a molar ratio of (1-5):(1-20):(0-20) in the presence of a catalyst, first undergoing a polymerization reaction at atmospheric pressure and 10-60℃ for 1-10 hours, and then undergoing acid removal treatment.
[0026] As a further preferred embodiment, the trialkoxyhydrosilane is a C1-C4 alkoxyhydrosilane, preferably at least one of trimethoxyhydrosilane, triethoxyhydrosilane, tripropoxyhydrosilane, or tributoxyhydrosilane; the catalyst is an acidic catalyst, preferably at least one of sulfuric acid, hydrochloric acid, trifluoromethanesulfonic acid, acidic resin, or acidic clay, and is used in an amount of 1%-5% wt of the total raw materials.
[0027] As a preferred option, the hydrogen-containing polysiloxane is an MDD'T structure hydrogen-containing polysiloxane, which is produced by mixing MM or MDM, polydimethyl mixed cyclosiloxane (DMC), trialkoxy hydrogen-containing silane, and methylhydrosiloxane in a raw material molar ratio of (1-5):(1-20):(0-20):(1-20) in the presence of a catalyst, first undergoing a polymerization reaction at atmospheric pressure and 10-60℃ for 1-10 hours, and then undergoing acid removal treatment.
[0028] As a further preferred embodiment, the trialkoxyhydrosilane is a C1-C4 alkoxyhydrosilane, preferably at least one of trimethoxyhydrosilane, triethoxyhydrosilane, tripropoxyhydrosilane, and tributoxyhydrosilane.
[0029] The methylhydrosiloxane is at least one of methylhydrosiloxane, methylhydrodimethoxysilane, and methylhydrodiethoxysilane;
[0030] The catalyst is an acidic catalyst, preferably at least one of the following: sulfuric acid, hydrochloric acid, trifluoromethanesulfonic acid, acidic resin, acidic clay, etc., and the amount used is 1%-5% wt of the total raw materials.
[0031] Preferably, the unsaturated polyether is a C2-C5 dual-terminated unsaturated alkenyl polyether, and more preferably, it is at least one of dual-terminated vinyl polyether, dual-terminated allyl polyether, dual-terminated butenyl polyether, dual-terminated methpropylene polyether, and dual-terminated pentene polyether.
[0032] Compared with existing technologies, the advantages of this invention are:
[0033] ① Increasing the Si-CH3 density leads to increased enrichment density at the interface, reducing the chain-breaking attack of water on Si-O-Si.
[0034] ② It has excellent acid and alkali resistance. A 0.1% aqueous solution at pH=3 and pH=12 can withstand 54℃ heat storage for 2 months.
[0035] ③ The raw materials are readily available, and there are already commercialized products;
[0036] ④ The process is simple and easy to industrialize;
[0037] ⑤ It is a non-ionic surfactant with strong compatibility and wide applicability. Attached Figure Description
[0038] Figure 1 This is a schematic diagram of the structure of the acid and alkali resistant organosilicon surfactant of the present invention.
[0039] Figure 2 The reaction process equation for the acid and alkali resistant organosilicon surfactant of the present invention is shown below. Detailed Implementation
[0040] The present invention will be further explained and illustrated below through embodiments, the purpose of which is to better understand the content of the present invention and not to limit the scope of protection of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0041] Example 1:
[0042] (1) Preparation of hydrogen-containing polysiloxane
[0043] In a three-necked flask, the air was replaced with nitrogen for 5 minutes. Then, 162 g (1 mol) of MM and 132 g (1 mol) of hydrogen-containing trimethoxysilane were added to the dry three-necked flask. With stirring, 2% wt sulfuric acid was added and the reaction was carried out at 20-40℃ for 6-8 hours. The hydrogen-containing polysiloxane with the MT'M structure was then neutralized with sulfuric acid.
[0044] (2) Preparation of acid and alkali resistant organosilicon surfactant A
[0045] In a four-necked flask, the air was purged with nitrogen for 5 minutes. Then, MT'M-structured hydrogen-containing polysiloxane and di-terminated allyl polyether (EO / PO = 8 / 0) were added to the flask at a molar ratio of 2.4:1. Under nitrogen protection, the mixture was heated to 50°C with stirring. 5 ppm of chloroplatinic acid catalyst was added, and the reaction was carried out at 130°C for 5 hours. The hydrogen conversion rate was measured to be 99%, yielding product A with a viscosity of 40.38 mm. 2 / s, the surface tension of a 0.1% wt aqueous solution is 21.03 mN / m.
[0046] Example 2:
[0047] (1) Preparation of hydrogen-containing polysiloxane
[0048] In a three-necked flask, the air was replaced with nitrogen for 5 minutes. Then, 162 g (1 mol) of MM, 264 g (2 mol) of hydrogen-containing trimethoxysilane, and 148 g (2 mol) of octamethylcyclotetrasiloxane D4 were added to the dry three-necked flask. With stirring, 2% wt of acidic resin was added, and the reaction was carried out at 20-40℃ for 6-8 hours. Then, the hydrogen-containing polysiloxane with the MT2'D2M structure was neutralized with sulfuric acid.
[0049] (2) Preparation of acid and alkali resistant organosilicon surfactant B
[0050] In a four-necked flask, the air was purged with nitrogen for 5 minutes. Then, hydrogen-containing polysiloxane with the MT2'D2M structure and dimethyl allyl polyether (EO / PO = 10 / 2) were added to the flask at a molar ratio of 1.2:1. Under nitrogen protection, the mixture was heated to 50°C with stirring. 10 ppm of chloroplatinic acid catalyst was added, and the reaction was carried out at 120°C for 5 hours. The hydrogen conversion rate was measured to be 99.2%, yielding product B with a viscosity of 120.89 mm. 2 / s, the surface tension of a 0.1% wt aqueous solution is 23.50 N / m.
[0051] Example 3:
[0052] (1) Preparation of hydrogen-containing polysiloxane
[0053] In a three-necked flask, the air was replaced with nitrogen for 5 minutes. Then, 162 g (1 mol) of MM, 132 g (1 mol) of methyltrimethoxysilane, and 60 g (1 mol) of tetramethylcyclotetrasiloxane were added to the dry three-necked flask. Sulfuric acid was added while stirring, and the reaction was carried out at 20-40℃ for 6-8 hours. The hydrogen-containing polysiloxane with the MTD'M structure was then neutralized with sulfuric acid.
[0054] (2) Preparation of acid and alkali resistant organosilicon surfactant C
[0055] In a four-necked flask, the air was purged with nitrogen for 5 minutes. Then, hydrogen-containing polysiloxane with MTD'M structure and divinyl-terminated polyether (EO / PO = 8 / 0) were added to the flask at a molar ratio of 2.4:1. Under nitrogen protection, the mixture was heated to 50°C with stirring. 5 ppm of chloroplatinic acid catalyst was added, and the reaction was carried out at 130°C for 5 hours. The hydrogen conversion rate was measured to be 99.2%, yielding product C with a viscosity of 50.2 mm. 2 / s, the surface tension of a 0.1% wt aqueous solution is 22.21 mN / m.
[0056] Example 4:
[0057] (1) Preparation of hydrogen-containing polysiloxane
[0058] In a three-necked flask, the air was replaced with nitrogen for 5 minutes. Then, 162 g (1 mol) of MM, 264 g (2 mol) of methyltrimethoxysilane, and 120 g (2 mol) of methylhydrogen mixed cyclosiloxane were added to the dry three-necked flask. With stirring, 2% wt of acidic resin was added and the reaction was carried out at 20-40℃ for 6-8 hours. Then, the hydrogen-containing polysiloxane with the MT2D2'M structure was neutralized with sulfuric acid.
[0059] (2) Preparation of acid and alkali resistant organosilicon surfactant D
[0060] In a four-necked flask, the air was purged with nitrogen for 5 minutes. Then, hydrogen-containing polysiloxane with the MT2D2'M structure and di-terminated allyl polyether (EO / PO = 10 / 2) were added to the flask at a molar ratio of 1.2:1. Under nitrogen protection, the mixture was heated to 50°C with stirring. 10 ppm of chloroplatinic acid catalyst was added, and the reaction was carried out at 120°C for 5 hours. The hydrogen conversion rate was measured to be 98.9%, yielding product D with a viscosity of 100.78 mm. 2 / s, the surface tension of a 0.1% wt aqueous solution is 22.80 mN / m.
[0061] Comparative Example 1:
[0062] (1) Preparation of hydrogen-containing polysiloxane
[0063] In a three-necked flask, the air was replaced with nitrogen for 5 minutes. Then, 162 g (1 mol) of MM and 74 g (1 mol) of tetramethylcyclotetrasiloxane were added to the dry three-necked flask. Sulfuric acid was added while stirring, and the reaction was carried out at 20-40℃ for 6-8 hours. The hydrogen-containing polysiloxane with the MD'M structure was then neutralized with sulfuric acid.
[0064] (2) Preparation of acid and alkali resistant organosilicon surfactant G
[0065] In a four-necked flask, the air was purged with nitrogen for 5 minutes. Then, MD'M-structured hydrogen-containing polysiloxane and di-terminated allyl polyether (EO / PO = 8 / O) were added to the flask at a molar ratio of 2.4:1. Under nitrogen protection, the mixture was heated to 50°C with stirring. 5 ppm of chloroplatinic acid catalyst was added, and the reaction was carried out at 130°C for 5 hours. The hydrogen conversion rate was measured to be 99.8%, yielding product G with a viscosity of 37.8 mm. 2 / s, the surface tension of a 0.1% wt aqueous solution is 20.50 mN / m.
[0066] Comparative Example 2:
[0067] (1) Preparation of hydrogen-containing polysiloxane
[0068] In a three-necked flask, the air was replaced with nitrogen for 5 minutes. Then, 162 g (1 mol) of MM and 74 g (1 mol) of tetramethylcyclotetrasiloxane were added to the dry three-necked flask. Sulfuric acid was added while stirring, and the reaction was carried out at 20-40℃ for 6-8 hours. The hydrogen-containing polysiloxane with the MD'M structure was then neutralized with sulfuric acid.
[0069] (2) Preparation of acid and alkali resistant organosilicon surfactant H
[0070] In a four-necked flask, air was purged with nitrogen for 5 minutes. Then, MT'M-structured hydrogen-containing polysiloxane and single-terminated allyl polyether (EO / PO = 8 / 0), with hydroxyl end capping, were added to the flask at a molar ratio of 1.2:1. Under nitrogen protection, the mixture was heated to 50°C with stirring. 5 ppm of chloroplatinic acid catalyst was added, and the reaction was carried out at 130°C for 5 hours. The hydrogen conversion rate was measured to be 99%, yielding product H with a viscosity of 35.5 mm. 2 / s, the surface tension of a 0.1% wt aqueous solution is 20.30 mN / m.
[0071] Acid and alkali resistance test:
[0072] Based on the experience of simulating 2 years of normal temperature by storing at 54℃ for 14 days, the acid and alkali resistant organosilicon surfactants prepared in the above examples and comparative examples were subjected to accelerated hydrolysis simulation by storing at 54℃ for 14 days. The stability data of the 0.1% aqueous solution at pH=3 and pH=12 were obtained by surface tension test, as shown in Tables 1 and 2 below.
[0073] Table 1. Stability data of surface tension test of 0.1% aqueous solution, pH=3, at 54℃ for thermal storage.
[0074] Surface tension mN / m Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 0 days 21.03 23.50 22.21 22.80 20.50 20.30 3 days 21.30 23.70 22.15 22.76 23.30 25.50 6 days 21.20 23.20 22.43 22.92 25.60 28.30 9 days 20.89 23.52 22.22 22.85 / / 12 days 21.05 23.60 22.53 23.01 / / 15 days 21.1 23.19 22.45 22.87 / /
[0075] Table 2. Stability data of surface tension test of 0.1% aqueous solution, pH=12, at 54℃ for thermal storage.
[0076] Surface tension mN / m Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 0 days 21.03 23.50 22.21 22.80 20.50 20.30 3 days 21.20 23.56 22.24 22.77 22.50 24.60 6 days 21.30 23.04 22.17 22.81 23.34 26.31 9 days 20.92 23.33 22.32 22.93 24.32 / 12 days 21.25 23.54 22.54 22.78 25.6 / 15 days 21.08 23.46 22.28 22.89 / /
[0077] The foregoing description of embodiments of the present invention, through which those skilled in the art are able to implement or use the present invention, will be readily apparent to those skilled in the art. Various modifications to these embodiments will be readily apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novelty disclosed herein.
Claims
1. An acid- and alkali-resistant organosilicon surfactant, the structure of which is as follows: ； Where m=1-20, n=0-20, a=0-20, b=0-20, and a+b>0, R is a C2-C5 straight-chain or branched saturated hydrocarbon group.
2. The acid and base resistant organosilicon surfactant of claim 1, wherein, m = 1-10, n = 0-10.
3. The acid and base resistant organosilicon surfactant of claim 1, wherein, m=1-5, n=0-5.
4. An acid- and alkali-resistant organosilicon surfactant, the structure of which is as follows: ； Where m=1-20, n=0-20, o=1-20, a=0-20, b=0-20, and a+b>0, and R is a C2-C5 straight-chain or branched saturated hydrocarbon group.
5. The acid and base resistant organosilicon surfactant of claim 4, wherein, m=1-10, n=0-10, o=1-10.
6. The acid and base resistant organosilicon surfactant of claim 5, wherein, m=1-5, n=0-5, o=1-5.
7. A method for preparing an acid- and alkali-resistant organosilicon surfactant according to any one of claims 4-6, characterized in that, The method includes the following steps: hydrogen-containing polysiloxane and unsaturated polyether undergo a hydrosilylation reaction in the presence of a catalyst, the molar ratio of hydrogen-containing polysiloxane to di-terminated alkenyl polyether is (0.8-2):(0.8-2), and the reaction is carried out under nitrogen protection at 60-130℃ for 2-10 hours with stirring to obtain an acid and alkali resistant organosilicon surfactant. The structural formula of hydrogen-containing polysiloxanes is as follows: ； The structural formula of the unsaturated polyether is as follows: ； Where P is CH3 and Q is H; Where m=1-20, n=0-20, o=1-20, a=0-20, b=0-20, and a+b>0, and R' is a C2-C5 straight-chain or branched unsaturated hydrocarbon group.
8. The method for preparing an acid and alkali resistant organosilicon surfactant according to claim 7, characterized in that, The catalyst is a platinum, rhodium, or cesium catalyst.
9. The method for preparing an acid and alkali resistant organosilicon surfactant according to claim 7, characterized in that, The catalyst is a chloroplatinic acid-platinum-vinyldisiloxane complex, used in an amount of 1-50 ppm of the total amount.
10. The method for preparing an acid- and alkali-resistant organosilicon surfactant according to claim 7, characterized in that, The unsaturated polyether is a double-ended C2-C5 unsaturated alkenyl polyether.
11. The method for preparing an acid- and alkali-resistant organosilicon surfactant according to claim 7, characterized in that, The unsaturated polyether is at least one of the following: divinyl polyether, diallyl polyether, dibutenyl polyether, dimethacryl polyether, and dipentene polyether.