Carboxyl silicone oil microemulsion as well as preparation method and application thereof

Abstract

The invention relates to a carboxyl silicone oil microemulsion and a preparation method and application thereof, and the carboxyl silicone oil microemulsion is prepared by emulsifying the following components in parts by mass: (A) 15-25 parts of carboxyl silicone oil with the number-average molecular weight of 2000-10000; (B) 5 to 10 parts of a fatty alcohol-polyoxyethylene ether nonionic surfactant, wherein the hydrophilic-lipophilic balance value (HLB) of the fatty alcohol-polyoxyethylene ether nonionic surfactant is 12.0 to 14.5; (C) 60 to 80 parts of water; (D) an alkaline conditioning agent, wherein the dosage of the alkaline conditioning agent enables the pH value of the obtained microemulsion system to be 7.5 or above; the turbidity of the carboxyl silicone oil micro-emulsion at the temperature of 25 DEG C is 20-60 NTU. The specific fatty alcohol-polyoxyethylene ether nonionic surfactant with the HLB value of 12.0-14.5 is selected, the pH value of the system is controlled to be 7.5 or above, and the carboxyl silicone oil microemulsion is prepared in cooperation with the optimized raw material ratio, has excellent stability and is suitable for fabric finishing and high-temperature and strong-alkali fabric refining procedures.

Description

Technical Field

[0001] This invention belongs to the field of organosilicon emulsion technology, specifically relating to a carboxyl silicone oil microemulsion, its preparation method, and its application. Background Technology

[0002] Carboxylated silicone oil, as an important organosilicon finishing agent, offers multiple advantages in fabric finishing. It improves the softness, elasticity, and smoothness of the fiber matrix, while also imparting good hydrophilicity and antistatic properties to fabrics. Furthermore, light-colored or white fabrics treated with it exhibit excellent whiteness, thus holding a unique position in the style and functional finishing of high-end fabrics. However, carboxylated silicone oil itself is an oily substance and cannot be directly applied to water-based textile processing; it must be emulsified to form a stable aqueous emulsion before use. Therefore, the preparation technology of carboxylated silicone oil emulsions is crucial for its successful application.

[0003] Currently, reports on carboxylated silicone oil emulsification mostly focus on the preparation of ordinary emulsions. Ordinary emulsions typically have a particle size ranging from 1 to 100 μm, appearing milky white and turbid. They generally suffer from difficulties in precisely controlling particle size, wide particle distribution, and poor stability, which to some extent limits the application of carboxylated silicone oil emulsions under harsh process conditions. Modern textile dyeing and finishing processes are developing towards high efficiency and shorter processes, with refining processes involving small liquor ratios, high temperatures, and strong alkalis becoming increasingly common. In such harsh environments, friction between fibers and between fibers and equipment intensifies, easily leading to persistent defects in fabrics such as warp threads and creases. Conventional carboxylated silicone oil emulsions are prone to demulsification, oil shedding, or failure in this high-temperature, strong-alkali, and high-friction environment, making it difficult for them to function continuously as effective finishing agents. In contrast, reports on emulsifying carboxylated silicone oil into microemulsions are rare. Microemulsions generally have a particle size of 10–100 nm, appearing transparent or translucent, and exhibiting better stability. Patent CN1613893A discloses a method for preparing a carboxyl silicone oil emulsion. This method involves reacting ester-modified silicone oil, small-molecule siloxanes, emulsifiers, catalysts, and water at 70-95°C for 5-15 hours to obtain the carboxyl silicone oil emulsion. The resulting emulsion has a milky white appearance with a slight bluish tint, and is a typical macroscopic emulsion with a wide particle size distribution, which directly affects its storage stability and application performance.

[0004] In summary, the existing technology lacks a method for effectively preparing carboxylated silicone oil microemulsions with high stability, fine particle size, and uniform distribution. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention provides a highly stable, fine-particle-size carboxylated silicone oil microemulsion, its preparation method, and its application in textile finishing.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A carboxyl silicone oil microemulsion is prepared by emulsification of the following components in parts by weight:

[0008] (A) 15-25 parts of carboxylated silicone oil with a number average molecular weight of 2000-10000;

[0009] (B) 5-10 parts of fatty alcohol polyoxyethylene ether nonionic surfactant with a hydrophilic-lipophilic balance (HLB) of 12.0-14.5;

[0010] (C) 60-80 parts water;

[0011] (D) An alkaline regulator, the amount of which is used to make the pH of the resulting microemulsion above 7.5;

[0012] The turbidity of the carboxylated silicone oil microemulsion at 25°C is 20~60 NTU.

[0013] The microemulsion described in this invention, due to its small particle size, reduces the scattering of visible light and macroscopically appears transparent or translucent. This characteristic can be specifically quantified by turbidity.

[0014] The carboxylated silicone oil described in this invention refers to a polysiloxane with one or more carboxyl groups (-COOH) on its molecular chain. These carboxyl groups can be located at the end of the molecular chain or on the side chain. Under conditions above pH 7.5, the carboxyl groups in the carboxylated silicone oil provide hydrophilicity and ionize into anionic charges, which is the basis for its ability to be emulsified into stable microemulsions.

[0015] Furthermore, the number-average molecular weight of the carboxyl silicone oil is 2000-5000, and the carboxyl content is 30-60 mg KOH / g. The number-average molecular weight of the carboxyl silicone oil is an important parameter for the formation of a stable microemulsion. The higher the molecular weight of the carboxyl silicone oil, the more difficult it is to emulsify into a microemulsion; while a low molecular weight makes emulsification easier, the resulting droplet interfacial film has insufficient strength, affecting the durability of the fabric finishing process. Controlling the molecular weight within the range of 2000-10000 (preferably 2000-5000) effectively balances the difficulty of emulsification with the application performance of the product. Furthermore, the fatty alcohol polyoxyethylene ether nonionic surfactant is selected from at least one of C12-C14 secondary alcohol polyoxyethylene ether, C12-C14 linear polyoxyethylene ether, and isomeric C12-C14 alcohol polyoxyethylene ether. The inventors have discovered that not all nonionic surfactants with HLB values ​​in the range of 12.0-14.5 can successfully prepare stable carboxyl silicone oil microemulsions. This invention selects a nonionic surfactant of fatty alcohol polyoxyethylene ether, whose fatty chain structure has good compatibility with carboxyl silicone oil, and whose ether bond is not easily hydrolyzed in a high temperature and strong alkaline environment, which is beneficial to maintaining the stability of the emulsion.

[0016] Preferably, the hydrophilic-lipophilic balance (HLB) of the fatty alcohol polyoxyethylene ether nonionic surfactant is 13.0 to 14.5. Within this preferred range, the resulting carboxylated silicone oil microemulsion has lower turbidity and higher transparency.

[0017] Furthermore, the water is pure water or deionized water; the alkalinity regulator is an organic amine, preferably triethanolamine. The function of the alkalinity regulator is to adjust the pH of the microemulsion within the above-mentioned range.

[0018] Preferably, the pH of the microemulsion is 8.0 to 9.0. pH is an important factor affecting the state of the microemulsion. When the pH is below 7.5, emulsification is difficult, and it is hard to form a stable microemulsion. As the pH increases, the stability of the system improves. However, a higher pH is not always better. An excessively high pH will significantly increase the viscosity of the microemulsion, which will cause inconvenience to subsequent application operations. Therefore, considering the balance between stability and ease of use, the pH should preferably be within the above-mentioned preferred range.

[0019] Secondly, the present invention provides a method for preparing the carboxylated silicone oil microemulsion, comprising the following steps:

[0020] (1) Premixing: Mix carboxylated silicone oil, fatty alcohol polyoxyethylene ether nonionic surfactant and alkaline regulator, and stir to form a mixture;

[0021] (2) Phase inversion emulsification: Under continuous stirring, control the system temperature at 20~60℃, add the prescribed amount of water dropwise to the mixture, and control the addition to be completed within 0.5~1h; after all the water is added, continue stirring at 20~60℃ for 1~2h to obtain crude microemulsion;

[0022] (3) Post-processing: The crude microemulsion was filtered to obtain carboxylated silicone oil microemulsion.

[0023] Further, the stirring in step (1) is: stirring at 200~500 rpm for 5~15 min; the filtration in step (3) is filtration using a 100~200 mesh sieve.

[0024] Thirdly, the present invention provides the application of the carboxylated silicone oil microemulsion in textile processing, wherein the microemulsion is used in the finishing process of fabrics or in the refining process of fabrics.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. This invention uses specific fatty alcohol polyoxyethylene ether nonionic surfactants with HLB values ​​of 12.0~14.5 and controls the system pH above 7.5. Combined with optimized raw material ratios, a carboxylated silicone oil microemulsion with a turbidity of 20~60 NTU at 25℃ is prepared, exhibiting a transparent or translucent appearance. This carboxylated silicone oil microemulsion demonstrates excellent stability; it remains transparent or translucent and homogeneous after 30 days at room temperature (25℃) and 14 days at 50℃, without stratification, demulsification, or oil shedding. In particular, the microemulsion prepared in the examples also remains stable and does not stratify after 30 days of storage at 50℃.

[0027] 2. The microemulsion remains stable in the high-temperature (98℃) and strong-alkali (sodium hydroxide) refining working solution that simulates actual textile processing, without breaking the emulsion or floating oil.

[0028] 3. When the microemulsion of the present invention is applied to the finishing of nylon fabrics, the hydrophilicity of the fabric is greatly improved, and the yellowing phenomenon of nylon fibers during high-temperature processing can be effectively inhibited. At the same time, when the microemulsion is used in the refining process of the fabric, it can effectively reduce defects such as warp marks, creases, and wrinkles generated during the refining process. Attached Figure Description

[0029] Figure 1 The images show actual photographs of the carboxylated silicone oil microemulsion prepared in Example 1 and the carboxylated silicone oil emulsions prepared in Comparative Examples 1 and 2. Detailed Implementation

[0030] The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to the following embodiments.

[0031] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are commercially available.

[0032] The carboxylated silicone oil, from Jiangxi Lanxing Xinghuo Organosilicon Co., Ltd., model BLUESIL FLD 1669, has a number-average molecular weight of approximately 2500 and a carboxyl content of approximately 45 mg KOH / g.

[0033] C12~C14 secondary alcohol polyoxyethylene ethers, purchased from Jiangsu SECCO Chemical, with specific models and HLB values ​​shown below:

[0034]

[0035] C12~C14 linear polyoxyethylene ether, purchased from Sasol, model AEO-9, HLB value 13.3.

[0036] Isotridecyl alcohol polyoxyethylene ether, purchased from Sasol (China) Chemical Co., Ltd., model MULTISO 1390, HLB value 13.3.

[0037] Octylphenol polyoxyethylene ether OP-10, purchased from Wanhua (Guangzhou) Supply Chain Service Co., Ltd., with an HLB value of 13.5.

[0038] Example 1

[0039]

[0040] Carboxylated silicone oil microemulsions were prepared according to the following steps based on the amounts of each raw material listed in the table above:

[0041] (1) Premixing: The above carboxylated silicone oil (BLUESIL FLD 1669), C12~C14 secondary alcohol polyoxyethylene ether (SECOL-90) and triethanolamine are mixed and stirred at 300 rpm for 10 min to form a mixture;

[0042] (2) Phase inversion emulsification: Under continuous stirring, the system temperature is controlled at 40℃, and the amount of pure water of the formula is added dropwise to the mixture, and the addition is completed within 1 hour; after all the pure water is added, the mixture is stirred continuously at 40℃ for 2 hours to obtain a transparent crude microemulsion (pH 8.4).

[0043] (3) Post-processing: The crude microemulsion was filtered using a 200-mesh filter to obtain carboxylated silicone oil microemulsion.

[0044] Example 2

[0045] The difference from Example 1 is that C12~C14 linear polyoxyethylene ether (AEO-9, HLB value 13.3) is used in the raw materials to replace C12~C14 secondary alcohol polyoxyethylene ether by mass.

[0046] The preparation method is the same as in Example 1.

[0047] Example 3

[0048] The difference from Example 1 is that isomeric tridecyl alcohol polyoxyethylene ether (MULTISO 1390, HLB value 13.3) is used in the raw materials to replace C12~C14 secondary alcohol polyoxyethylene ether by mass.

[0049] The preparation method is the same as in Example 1.

[0050] Example 4

[0051] The difference from Example 1 is that the C12~C14 secondary alcohol polyoxyethylene ether in the raw materials is a blend of SECOL-50 and SECOL-90, that is, the HLB values ​​of the surfactants are different, specifically:

[0052]

[0053] Note: The HLB value of the compound surfactant obtained by mixing SECOL-50 and SECOL-90 at a mass ratio of 2.3:4.6 is 12.3.

[0054] The preparation method is the same as in Example 1.

[0055] Example 5

[0056] The difference from Example 1 is that the C12~C14 secondary alcohol polyoxyethylene ether in the raw material is SECOL-120 (HLB value is 14.5), that is, the HLB value of the surfactant is different.

[0057] The preparation method is the same as in Example 1.

[0058] Example 6

[0059] The difference from Example 1 is that the amount of triethanolamine used is 1 part, and the pH of the microemulsion obtained in step (2) is 7.7.

[0060] Example 7

[0061] The difference from Example 1 is that the amount of triethanolamine used is 6 parts, and the pH of the microemulsion obtained in step (2) is 9.0.

[0062] Example 8

[0063] The difference from Example 1 is that the amount of raw materials used is different, specifically:

[0064]

[0065] The preparation method is the same as in Example 1, and the pH value of the system is 8.5.

[0066] Example 9

[0067] The difference from Example 1 is that the amount of raw materials used is different, specifically:

[0068]

[0069] The preparation method is the same as in Example 1, and the pH value of the system is 8.5.

[0070] Comparative Example 1

[0071] The difference from Example 1 is that octylphenol polyoxyethylene ether OP-10 (HLB value 13.5) is used in the raw materials to replace C12~C14 secondary alcohol polyoxyethylene ether (SECOL-90) by mass.

[0072] A milky white, turbid emulsion (non-microemulsion) was obtained.

[0073] Comparative Example 2

[0074] The difference from Example 1 is that the C12~C14 secondary alcohol polyoxyethylene ether in the raw materials is SECOL-150, that is, the HLB value of the surfactant is different, and the HLB value of SECOL-150 is 15.3.

[0075] Finally, a milky white emulsion (non-microemulsion) was obtained.

[0076] Comparative Example 3

[0077] The difference from Example 1 is that the C12~C14 secondary alcohol polyoxyethylene ether in the raw materials is a combination of SECOL-50 and SECOL-90, that is, the HLB values ​​of the surfactants are different.

[0078]

[0079] Note: The HLB value of the compound surfactant obtained by mixing SECOL-50 and SECOL-90 at a mass ratio of 4.6:2.3 is 11.4.

[0080] The preparation method is the same as in Example 1, and a milky white, turbid emulsion (non-microemulsion) is finally obtained.

[0081] Comparative Example 4

[0082] The difference from Example 1 is that the amount of triethanolamine used is 0.6 parts, and the pH of the system in step (2) is 6.6.

[0083] Finally, a milky white emulsion (non-microemulsion) was obtained.

[0084] Comparative Example 5

[0085] The difference from Example 1 is that the amount of SECOL-90 used is 4 parts.

[0086] The preparation method is the same as in Example 1, and a milky white, turbid emulsion (non-microemulsion) is finally obtained.

[0087] The preparation information for the above embodiments and comparative examples is summarized in Table 1.

[0088] Table 1. Preparation information for each example and comparative example.

[0089]

[0090] Photos of the carboxylated silicone oil microemulsion prepared in Example 1 and the carboxylated silicone oil emulsions prepared in Comparative Examples 1 and 2 are shown below. Figure 1 As shown.

[0091] Testing and Analysis

[0092] Turbidity and stability tests were performed on the samples prepared in the examples and comparative examples.

[0093] Turbidity Testing: The turbidity of the prepared microemulsions and emulsions at 25℃ was measured using a WGZ-50 portable turbidimeter from Shanghai Instrument & Electronics Co., Ltd. Generally, microemulsions, due to their extremely small particle size (typically less than 100 nm), exhibit reduced scattering of visible light, resulting in lower turbidity (typically below 100 NTU) and a macroscopically transparent or translucent appearance. Ordinary emulsions, on the other hand, have larger particle sizes, higher turbidity, and a milky white appearance. The smaller the particle size of the microemulsion or emulsion, the lower the measured turbidity value, the more transparent it appears, and generally, the better its stability.

[0094] Stability test: According to HG / T4920-2016 "Determination of storage stability of textile dyeing and finishing auxiliaries", the prepared microemulsion and emulsion were left to stand at room temperature of 25℃ and 50℃ respectively, and their appearance changes were observed periodically. Whether they became turbid or separated (such as oil stains or flocculation) was recorded.

[0095] The turbidity and stability test results of the microemulsions and emulsions prepared in each embodiment and comparative example are shown in Table 2.

[0096] Table 2 Turbidity and Stability Tests

[0097]

[0098] As shown in Table 2, all examples prepared microemulsions with a turbidity of 20-60 NTU at 25°C and a transparent or semi-transparent appearance. All microemulsions exhibited good storage stability at both 25°C and 50°C. In particular, the microemulsions of the preferred examples had even lower turbidity, not exceeding 40 NTU, and remained stable without stratification after 30 days of storage at 50°C.

[0099] In Comparative Example 1, octylphenol polyoxyethylene ether with an HLB value of 13.5 was used as the surfactant. Although the HLB value of octylphenol polyoxyethylene ether was within the range of this invention, a transparent microemulsion was not obtained, and it separated into layers after 20 days of storage at 25°C and after 5 days of storage at 50°C, indicating poor stability at both 25°C and 50°C. Comparative Examples 2 and 3 used surfactants with excessively high (15.3) and excessively low (11.4) HLB values, respectively, and neither formed a stable microemulsion. Both separated into layers after 14 days of storage at 50°C. The pH of the system in Comparative Example 4 was outside the range of this invention. Although the resulting emulsion did not separate macroscopically after 30 days of storage at 25°C, it separated into layers after 10 days of storage at 50°C. The amount of surfactant used in Comparative Example 5 was too low, resulting in insufficient emulsification and high turbidity of the resulting emulsion, with poor stability at both 25°C and 50°C.

[0100] To verify the practical application effect of the microemulsion prepared in the examples in textile processing, the following application performance tests were conducted:

[0101] 1) Application in the finishing of nylon fabrics

[0102] White nylon knitted fabric was selected as the test fabric, and the microemulsion prepared in the examples was formulated into working solutions of 40 g / L. The process used was: padding (one dip-one squeeze) → drying (drying at 130℃ for 2 minutes) → fixing (drying at 180℃ for 1 minute). The water absorption and whiteness values ​​of the fabrics treated with the above process were tested, with untreated blank fabric as a control. Water absorption was measured according to AATCC 79-2018 "Textiles - Test Method for Water Absorption", and the time (seconds) required for a water droplet to be completely absorbed was recorded. The shorter the time, the better the water absorption. Whiteness was measured according to GB / T 8424.2-2001 "Textiles - Test for Color Fastness - Determination of Whiteness", using a whiteness meter. The test results showed that after the nylon fabric was treated with the carboxylated silicone oil microemulsion prepared in the examples of this invention, its hydrophilicity was greatly improved, and the water absorption time was shortened from 22 seconds for the blank sample to less than 2 seconds. Meanwhile, the high-temperature yellowing of nylon was effectively suppressed, and its whiteness value did not decrease significantly after being fixed at 180℃.

[0103] 2) Application in fabric refining

[0104] Test method: Simulating actual high-temperature strong alkali refining conditions, a refining working solution was prepared: sodium hydroxide 2 g / L, refining agent SUNMORL BK-30 2 g / L, and the microemulsion prepared in the example was added to each solution. The refining working solution was heated to 98°C and held for 30 minutes, then allowed to cool naturally to room temperature. The appearance of the working solution after heating and cooling was observed and recorded.

[0105] Test results show that all refining working solutions containing the microemulsions of the embodiments of the present invention, after being heated at 98°C for 30 minutes and cooled to room temperature, maintained a clear, uniform, and stable appearance, without any demulsification, flocculation, oil floating, or stratification. This indicates that the carboxylated silicone oil microemulsion of the present invention has excellent alkali resistance and high-temperature stability, and can remain stable in harsh refining environments. Therefore, it can play a continuous lubricating role during the refining process, helping to reduce wrinkles, warp defects, and other defects caused by friction in fabrics, and improving the overall quality of the fabric.

Claims

1. A carboxyl silicone oil microemulsion characterized in that, Prepared by emulsification from components comprising the following parts by mass: (A) 15-25 parts of a carboxyl silicone oil having a number average molecular weight of 2000-10000; (B) 5-10 parts of a fatty alcohol polyoxyethylene ether nonionic surfactant having a hydrophilic-lipophilic balance (HLB) of 12.0-14.5; (C) 60-80 parts of water; (D) an alkaline adjusting agent in an amount such that the pH of the resulting microemulsion is above 7.5; The carboxyl silicone oil microemulsion has a turbidity of 20-60 NTU at 25°C.

2. The carboxyl silicone oil microemulsion according to claim 1, characterized by, The carboxyl silicone oil has a number average molecular weight of 2000-5000 and a carboxyl content of 30-60 mg KOH / g.

3. The carboxyl silicone oil microemulsion according to claim 1, characterized by, The fatty alcohol polyoxyethylene ether nonionic surfactant is selected from at least one of C12-C14 secondary alcohol polyoxyethylene ether, C12-C14 linear polyoxyethylene ether, and isomeric C12-C14 alcohol polyoxyethylene ether.

4. The carboxyl silicone oil microemulsion according to claim 1, characterized by, The fatty alcohol polyoxyethylene ether nonionic surfactant has a hydrophilic-lipophilic balance of 13.0-14.

5.

5. The carboxyl silicone oil microemulsion according to claim 1, characterized by, The water is pure water or deionized water; and the alkaline adjusting agent is an organic amine, preferably triethanolamine.

6. The carboxysilicone oil microemulsion according to claim 1, characterized in that, The pH of the microemulsion is 8.0-9.

0.

7. A process for the preparation of a carboxy silicone oil microemulsion according to any one of claims 1 to 6, characterized in that, Comprising the following steps: (1) Pre-mixing: mixing the carboxyl silicone oil, the fatty alcohol polyoxyethylene ether nonionic surfactant, and the alkaline adjusting agent, and stirring to form a mixture; (2) Phase inversion emulsification: under continuous stirring, controlling the system temperature to be 20-60°C, and adding the formula amount of water to the mixture dropwise, controlling the dropwise addition to be completed within 0.5-1 h; after all the water is added, continuously stirring at 20-60°C for 1-2 h to obtain a crude microemulsion; (3) Post-treatment: filtering the crude microemulsion to obtain the carboxyl silicone oil microemulsion.

8. The production method according to claim 7, characterized by, The stirring in step (1) is stirring at 200-500 rpm for 5-15 min; and the filtering in step (3) is filtering using a 100-200 mesh screen.

9. Use of the carboxylic silicone oil microemulsion according to any one of claims 1 to 6 in textile processing, characterized in that, The microemulsion is used in a finishing process of a fabric or in a refining process of a fabric.

10. A textile finishing agent, characterized in that, A fabric care product comprising the carboxyl silicone oil microemulsion of any one of claims 1-6.

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