Fluorine-free oil repellent fabric finishing agent and preparation method thereof

Abstract

The present application belongs to the technical field of textile auxiliaries, and particularly relates to a fluorine-free oil-repellent fabric finishing agent and a preparation method thereof.The fluorine-free oil-repellent fabric finishing agent comprises the following components in mass fractions: POSS / PDMS side chain modified acrylate copolymer 10-25 parts, reactive re-entrant microgel 3-10 parts, crosslinking agent 2-15 parts, and water 20-120 parts; wherein the reactive re-entrant microgel comprises a crosslinked microgel soft core and nano-silicon dioxide combined on the surface of the crosslinked microgel soft core; wherein the combination comprises covalent combination through a beta-hydroxyl amine connecting bond.The finishing agent of the present application shows synergistic effects in terms of oil contact angle, oil-repellent grade and wash fastness retention rate.

Description

Technical Field

[0001] This invention belongs to the field of textile auxiliary technology, and in particular relates to a fluorine-free oil-repellent fabric finishing agent and its preparation method. Background Technology

[0002] Fluorinated acrylate finishing agents and fluorinated polyurethane finishing agents can significantly reduce the surface energy of fabrics, giving them water-repellent, oil-repellent, and stain-resistant properties. However, some fluorinated compounds have poor environmental durability and face regulatory pressure. Therefore, developing fluorine-free oil-repellent finishing systems has become an important direction in the field of textile finishing.

[0003] Existing fluorine-free fabric finishing agents typically employ paraffin wax, long-chain alkyl acrylates, silicone, polyurethane, or nano-silica to construct low surface energy and rough surface structures. These systems readily achieve high water contact angles, but their resistance to wetting by vegetable oils, sebum, and low-surface-tension oils remains limited. While ordinary silicone oils or PDMS coatings possess low adhesion properties, their surfaces are typically quite smooth, making it difficult to provide stable support for oil droplets. Although ordinary nano-silica can increase roughness, the particles are easily detached during washing, friction, and bending. Summary of the Invention

[0004] The present invention aims to solve at least one of the above-mentioned technical problems existing in the prior art. To this end, the present invention proposes a fluorine-free oil-repellent fabric finishing agent to solve the problems of insufficient oil-repellent performance of ordinary fluorine-free finishing agents and poor durability of ordinary inorganic particles.

[0005] The present invention also provides a method for preparing a fluorine-free oil-repellent fabric finishing agent.

[0006] According to a first aspect of the present invention, a fluorine-free oil-repellent fabric finishing agent comprises, by weight, the following components: 10-25 parts of POSS / PDMS side-chain modified acrylate copolymer; 3-10 parts of reactive re-entrapment microgel; 2-15 parts of crosslinking agent; 20-120 parts water; The reactive reentry microgel includes a cross-linked microgel soft core and nano-silica bonded to the surface of the cross-linked microgel soft core; the bonding includes covalent bonding via β-hydroxyamine linkages.

[0007] The fluorine-free oil-repellent fabric finishing agent of the present invention mainly forms a stable multi-component aqueous dispersion system at room temperature. When it is applied to the fabric and baked at 145~160 °C, the crosslinking agent (preferably blocked isocyanate) is unblocked, and the isocyanate groups react with the hydroxyl groups in the POSS / PDMS side-chain modified acrylate copolymer and the reactive re-entry microgel to form urethane crosslinking bonds. At the same time, the residual epoxy, amino and silanol groups on the surface of the reactive re-entry microgel can participate in the interfacial reaction or form a strong interfacial interaction, so that the low surface energy POSS / PDMS side-chain modified acrylate copolymer and the reactive re-entry microgel are jointly fixed on the fiber surface to form a continuous-particulate composite crosslinked oil-repellent layer.

[0008] According to some embodiments of the present invention, the finishing agent comprises the following components in parts by weight: 10 to 20 parts of POSS / PDMS side-chain modified acrylate copolymer (e.g., any value from 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or any range between two). 3 to 8 parts of reactive re-introduced microgel (e.g., any value of 3, 4, 5, 6, 7, 8 or any range between two). 2 to 10 parts of crosslinking agent (for example, any value of 2, 3, 4, 5, 6, 7, 8, 9, 10 or any range between two). Water 20 to 120 parts (for example, any value from 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120 or any range between two).

[0009] According to some embodiments of the present invention, the POSS / PDMS side-chain modified acrylate copolymer is prepared by the following steps: The monofunctional (meth)acrylate esterified silsesquioxane, (meth)acrylate monoterminated polydimethylsiloxane, the first (meth)acrylate monomer, and the first emulsifier are mixed and pre-emulsified. An initiator is then added under a protective atmosphere to carry out the first polymerization reaction, thus obtaining the product.

[0010] This invention uses commercially available monofunctional (meth)acrylated POSS and (meth)acrylate monoterminated PDMS as reactive organosilicon monomers, and performs emulsion copolymerization with long-chain alkyl monomers and conventional acrylate monomers to obtain POSS / PDMS side-chain modified acrylate copolymers.

[0011] According to some embodiments of the present invention, the monofunctional (meth)acrylated silsesquioxane has a mass ratio of the (meth)acrylate monoterminated polydimethylsiloxane to the first (meth)acrylate monomer of 8~25:10~30:35~80, for example, 8~20:10~25:40~80, 10~20:15~25:50~80, 12~18:18~24:60~80, or 1:1.2~1.5:4~5.

[0012] According to some embodiments of the present invention, the monofunctional (meth)acrylated silsesquioxane is isobutyl methacrylate (POSS).

[0013] According to some embodiments of the present invention, the (meth)acrylate-terminated polydimethylsiloxane is a methacryloyloxypropyl-terminated polydimethylsiloxane. Preferably, the number-average molecular weight of the (meth)acrylate-terminated polydimethylsiloxane is 800-1200 g / mol.

[0014] According to some embodiments of the present invention, the first (meth)acrylic monomer includes C12-C22 long-chain alkyl methacrylate, hydroxyethyl methacrylate, glycidyl methacrylate, butyl acrylate, methyl methacrylate, and (meth)acrylic acid, in a mass ratio of 10-30:3-12:2-10:10-30:10-30:0.5-4, for example, 10-25:3-10:3-10:10-20:10-25:1-4, 10-20:5-10:5-10:15-20:10-20:1-3, 15-20:6-8:5-8:15-20:12-18:1-3, or about 18:7:6:17:15:2.

[0015] Preferably, the C12~C22 long-chain alkyl methacrylate is stearyl methacrylate.

[0016] According to some embodiments of the present invention, the first emulsifier includes at least one of nonionic emulsifiers (e.g., fatty alcohol polyoxyethylene ether AEO-7, AEO-9; alkylphenol polyoxyethylene ether APEO, such as nonylphenol polyoxyethylene ether) and anionic emulsifiers (e.g., sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, sodium lauryl sulfate, sodium stearate).

[0017] According to some embodiments of the present invention, the initiator includes ammonium persulfate.

[0018] According to some embodiments of the present invention, the reaction temperature of the first polymerization reaction is 60~90 °C (e.g., 70~90 °C, 70~80 °C, about 75 °C), and the reaction time is 1~4 h (e.g., 1~3 h, about 2 h).

[0019] According to some embodiments of the present invention, the POSS / PDMS side-chain modified acrylate copolymer exists in solution form, and the solid content of the POSS / PDMS side-chain modified acrylate copolymer solution is 30wt%~40wt%, and the pH is 6~7.

[0020] According to some embodiments of the present invention, the mass ratio of the cross-linked microgel soft core to the nano-silica is 1:(0.2~0.6), for example 1:(0.2~0.5) or 1:(0.3~0.4).

[0021] According to some embodiments of the present invention, the particle size of the reactive reentry microgel is 150~350 nm.

[0022] According to some embodiments of the present invention, the average particle size of the nano-silica is 40-70 nm. The nano-silica is distributed on the surface of the cross-linked microgel soft core, forming hard protrusions.

[0023] According to some embodiments of the present invention, the reactive reentry microgel is prepared by the following steps: The second (meth)acrylic acid monomer is mixed with the second emulsifier and pre-emulsified. An initiator is added under a protective atmosphere to carry out a second polymerization reaction to obtain an epoxy-containing crosslinked microgel soft core. The epoxy-containing crosslinked microgel soft core is then subjected to a ring-opening reaction with aminated nano-silica to covalently bond the nano-silica to the surface of the crosslinked microgel soft core, thus obtaining the final product.

[0024] This invention uses epoxy-containing cross-linked microgels as flexible soft cores. Through the ring-opening reaction between epoxy groups and amino groups on the surface of amino-modified nano-silica, nano-silica is fixed on the surface of the cross-linked microgels, forming a reactive reentry microgel with a soft core and hard protrusions.

[0025] According to some embodiments of the present invention, the second (meth)acrylate monomer comprises glycidyl methacrylate, butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, and ethylene glycol dimethacrylate in a mass ratio of 15~35:20~45:20~45:2~10:0.5~5 (e.g., 15~30:20~40:20~40:2~8:0.5~4, 20~30:25~40:2~8:0.5~3, 20~30:30~40:30~40:2~6:1~3, or about 10~12:15~18:15~18:1~3:1).

[0026] According to some embodiments of the present invention, the second emulsifier includes at least one of nonionic emulsifiers (e.g., fatty alcohol polyoxyethylene ether AEO-7, AEO-9; alkylphenol polyoxyethylene ether APEO, such as nonylphenol polyoxyethylene ether) and anionic emulsifiers (e.g., sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, sodium lauryl sulfate, sodium stearate).

[0027] According to some embodiments of the present invention, the initiator includes ammonium persulfate.

[0028] According to some embodiments of the present invention, the reaction temperature of the second polymerization reaction is 60~90 °C (e.g., 70~90 °C, 70~80 °C, about 75 °C), and the reaction time is 1~4 h (e.g., 1~3 h, about 2 h).

[0029] According to some embodiments of the present invention, the epoxy-containing cross-linked microgel soft core exists in solution form; preferably, the solid content of the epoxy-containing cross-linked microgel soft core solution is 30wt%~40wt%.

[0030] According to some embodiments of the present invention, the aminated nano-silica is prepared by the following steps: Prepare an alcohol-water dispersion of nano-silica, add an aminosilane coupling agent, adjust the pH of the system to 8.5-11.0, and react at 55-65 °C for 3-5 h to obtain the final product; The molar mass ratio of the amino group in the aminosilane coupling agent to the silica in the nano-silica is 0.8~1.0 mmol / g.

[0031] Preferably, the average particle size of the nano-silica is 10~100 nm, and more preferably 30~70 nm.

[0032] Preferably, the alcohol-water mixed solvent is a mixture of C1-C4 monohydric alcohol and water, wherein the mass ratio of monohydric alcohol to water is (8-10):1; preferably, the alcohol-water mixed solvent is composed of 90 parts by mass of anhydrous ethanol and 10 parts by mass of deionized water.

[0033] Preferably, the nano-silica is dispersed by ultrasonic treatment for 10-60 min, preferably 20 min.

[0034] Preferably, the aminosilane coupling agent is selected from at least one of 3-aminopropyltriethoxysilane (APTES), 3-aminopropyltrimethoxysilane (APTMS), and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane; more preferably, it is 3-aminopropyltriethoxysilane.

[0035] Preferably, ammonia is used to adjust the pH of the system to 9.0~10.0.

[0036] Preferably, the aminated nano-silica exists in solution form, and preferably, the solid content of the aminated nano-silica solution is 15wt%~25wt%.

[0037] According to some embodiments of the present invention, the ring-opening reaction is carried out at a pH of 7.5 to 8.5 (preferably 8), at a temperature of 40 to 60°C (preferably 45°C), and for a time of 3 to 5 h (preferably 4 h).

[0038] According to some embodiments of the present invention, the reactive reentrant microgel exists in solution form, preferably, the solid content of the reactive reentrant microgel solution is 20wt%~30wt%.

[0039] According to some embodiments of the present invention, the fluorine-free oil-repellent fabric finishing agent comprises, by weight, 0.2 to 4 parts (e.g., 0.4 to 3, 0.4 to 2, 0.5 to 1, 0.6 to 0.8) of wetting and dispersing agent.

[0040] Preferably, the wetting and dispersing agent is a polyether-modified polysiloxane nonionic wetting and dispersing agent.

[0041] A method for preparing a fluorine-free oil-repellent fabric finishing agent according to a second aspect of the present invention includes the following steps: The POSS / PDMS side-chain modified acrylate copolymer, the reactive re-entrant microgel, the crosslinking agent, and water are mixed and the pH is adjusted to 6.0-7.0 to obtain the final product.

[0042] According to some embodiments of the present invention, the mixing is carried out by stirring at 20~30 °C for 0.5~1 h.

[0043] A method of using a fluorine-free oil-repellent fabric finishing agent according to a third aspect embodiment of the present invention includes the following steps: The finishing agent working solution is applied to the fabric, and the crosslinking agent is desealed and crosslinked and cured by pre-drying and baking to obtain a fluorine-free oil-repellent fabric.

[0044] According to some embodiments of the present invention, the pre-baking temperature is 90~110 ℃ and the time is 1~5 min.

[0045] According to some embodiments of the present invention, the baking temperature is 145~160 ℃ and the time is 1~5 min.

[0046] According to some embodiments of the present invention, at least the following beneficial effects are achieved: This invention reacts an epoxy-containing microgel soft core with aminated nano-silica to form a soft core / hard protrusion structure, which combines flexible deformation and micro / nano rough support. Furthermore, the nano-silica is fixed through a chemical reaction, resulting in superior wash and abrasion resistance compared to a physically dispersed nano-silica system.

[0047] POSS cage-like side groups, PDMS flexible side chains, long-chain alkyl segments, and reentry microgels can synergistically reduce oil adhesion and oil penetration tendency, and can improve the anti-wetting ability of fabrics against vegetable oil and sebum contaminants under fluorine-free conditions.

[0048] The finishing agent of the present invention is an aqueous emulsion system, which can be used in conventional two-dip two-nip, pre-drying and baking processes, and is suitable for cotton, polyester, nylon and their blended fabrics.

[0049] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0050] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is the infrared spectrum of the POSS / PDMS side-chain modified acrylate copolymer obtained in step (1) of Example 1; Figure 2 This is a TEM image of the reactive reentrant microgel obtained in step (2) of Example 1; Figure 3 This is a SEM image of the reactive reentrant microgel obtained in step (2) of Example 1; Figure 4 These are SEM images of cotton fabrics before and after treatment with the finishing agent in Example 1, where a) corresponds to before treatment and b) corresponds to after treatment. Detailed Implementation

[0051] The following will describe the concept and technical effects of the present invention clearly and completely with reference to embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.

[0052] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0053] "And / or" is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0054] Unless otherwise specified, "room temperature" in this invention means (25±5)℃.

[0055] Unless otherwise specified, “about” in this invention means ±2%.

[0056] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0057] Example 1 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is as follows: (1) Preparation of POSS / PDMS side-chain modified acrylate copolymer emulsion: 15 parts by weight of isobutyl methacrylate POSS (T8 cage structure, monomethacrylate functionalized, purchased from Hybrid Plastics, MA0702 or equivalent, CAS 307531-94-8), 20 parts by weight of monomethacryloxypropylterminated polydimethylsiloxane (purchased from Gelest MCR-M11 or equivalent, CAS 146632-07-7, number average molecular weight approximately 1000 g / mol), 18 parts by weight of stearyl methacrylate (CAS 32360-05-7), 7 parts by weight of hydroxyethyl methacrylate (CAS 868-77-9), 6 parts by weight of glycidyl methacrylate (CAS 106-91-2), and 17 parts by weight of butyl acrylate (CAS 307531-94-8) were prepared. 141-32-2), 15 parts by weight of methyl methacrylate (CAS 80-62-6), 2 parts by weight of methacrylic acid (CAS 79-41-4), 2.2 parts by weight of fatty alcohol polyoxyethylene ether AEO-9, and 0.8 parts by weight of sodium dodecyl sulfate were mixed with 120 parts by weight of deionized water and subjected to high-speed shearing for 20 min to obtain a homogeneous pre-emulsion. Separately, 66 parts by weight of deionized water were added to the reactor, and nitrogen gas was purged for 30 min before the temperature was raised to 75 °C. The obtained pre-emulsion and a 10 wt% aqueous solution prepared from 0.6 parts by weight of ammonium persulfate (CAS 7727-54-0) were added dropwise to the reactor over 3 h. After the addition was complete, the reaction was continued at this temperature for 2 h. The mixture was cooled to room temperature, the pH was adjusted to 6.5 with ammonia, and filtered to obtain a POSS / PDMS side-chain modified acrylate copolymer emulsion.

[0058] The solid content of the obtained copolymer emulsion was determined by oven constant weight method: about 2.0 g of emulsion was weighed and dried at (105±2)℃ to constant weight. The solid content of the copolymer emulsion in this example was controlled at about 35 wt% by calculating the residual mass after drying / sample mass × 100%.

[0059] The infrared spectrum of the POSS / PDMS side-chain modified acrylate copolymer is shown below. Figure 1 The image shows approximately 2950–2850 cm. -1 The absorption peak at this point is the CH stretching vibration of aliphatic molecules, approximately 1720–1730 cm⁻¹. -1 The absorption peak at approximately 1260 cm⁻¹ corresponds to the C=O stretching vibration of acrylate. -1 Characteristic absorption of Si-CH3 can be observed at approximately 1090–1020 cm⁻¹. -1 Absorption occurs at approximately 910 cm⁻¹ due to the Si-O-Si stretching vibration.-1 Characteristic absorptions of GMA side group epoxy groups can still be observed nearby; meanwhile, at approximately 1635 cm⁻¹ in the monomer... -1 The C=C characteristic peaks nearby were significantly weakened, indicating that the monomers containing double bonds underwent free radical polymerization.

[0060] Combining raw material structure, free radical polymerization pathway and Figure 1 The characteristic absorption indicates that the resulting copolymer has an acrylate backbone, with POSS and PDMS introduced into the side chains as polymerizable macromonomers.

[0061] (2) Preparation of reactive reentry microgels: 25 parts by weight of glycidyl methacrylate (CAS 106-91-2), 34 parts by weight of butyl acrylate (CAS 141-32-2), 35 parts by weight of methyl methacrylate (CAS 80-62-6), 4 parts by weight of hydroxyethyl methacrylate (CAS 868-77-9), and 2 parts by weight of ethylene glycol dimethacrylate (CAS 97-90-5) were mixed with 2.2 parts by weight of AEO-9, 0.8 parts by weight of sodium dodecyl sulfate, and 150 parts by weight of deionized water, and pre-emulsified for 20 min to obtain a pre-emulsion. Add 40 parts by mass of deionized water to the reactor, heat to 75 °C and purge with nitrogen for 30 min. Simultaneously add the obtained pre-emulsion and 0.6 parts by mass of ammonium persulfate to the reactor dropwise over 3 h. After the addition is complete, continue to keep the reactor at the temperature for 2 h to obtain a dispersion of epoxy-crosslinked microgel soft core with a solid content of about 34 wt%.

[0062] In the above emulsion polymerization process, butyl acrylate and methyl methacrylate constitute the main acrylate segments, glycidyl methacrylate and hydroxyethyl methacrylate introduce epoxy and hydroxyl side groups respectively, and ethylene glycol dimethacrylate forms trace crosslinking points through two polymerizable double bonds, thereby obtaining a microgel soft core with a three-dimensional slightly crosslinked structure.

[0063] Aminated nano-silica was prepared using a silanization method: 10 parts by mass of nano-silica with an average particle size of approximately 50 nm were dispersed in 90 parts by mass of anhydrous ethanol and 10 parts by mass of deionized water, and ultrasonically dispersed for 20 min. Then, 2.0 parts by mass of 3-aminopropyltriethoxysilane (APTES) were added, and the pH was adjusted to 9.0–10.0 with ammonia. The mixture was stirred at 60 °C for 4 h. After the reaction, the mixture was centrifuged and washed three times with ethanol, then dispersed again in deionized water to prepare a 20 wt% aminated nano-silica dispersion. Based on the APTES dosage, the theoretical amino dosage is approximately 0.90 mmol / g SiO2.

[0064] The above-mentioned aminated nano-silica dispersion was added to the epoxy-crosslinked microgel core dispersion, making the solid mass ratio of aminated nano-silica to microgel core 0.35:1. The pH was adjusted to 8.0 with sodium bicarbonate, and the reaction was carried out at 45°C with stirring for 4 h. The amino groups on the silica surface and the epoxy groups on the microgel core surface underwent a nucleophilic ring-opening reaction to form a β-hydroxyamine linkage structure, thereby fixing the nano-silica to the surface of the microgel core in a chemical bond manner, resulting in a reactive re-injection microgel dispersion; before use, its solid content was adjusted to approximately 25 wt% with deionized water.

[0065] The morphology of the reactive reentrant microgels is shown in the figure. Figure 2 and Figure 3 .Depend on Figure 2 TEM images show that the microgel particles have a diameter of 150–350 nm, are nearly spherical or clustered, and have small, high-electron-density inorganic particle protrusions distributed on the surface. The hard protrusions have a diameter of approximately 40–70 nm. Magnified local images show that the nanoparticles are concentrated around the soft core, forming a distinctly rough outer contour. Figure 3 The SEM images show that there are discrete granular protrusions on the particle surface, and the surface roughness is significantly improved compared with ordinary smooth microspheres, which is consistent with the characteristics of soft core / hard protrusion type reentry structure.

[0066] (3) Preparation of fluorine-free oil-repellent and stain-resistant finishing agent: 52 parts by mass of the POSS / PDMS side-chain modified acrylate copolymer emulsion obtained in step (1), 20 parts by mass of the reactive re-entrant microgel dispersion obtained in step (2), 6 parts by mass of caprolactam-blocked hexamethylene diisocyanate (HDI) trimer water-dispersing crosslinking agent, 0.8 parts by mass of polyether-modified polysiloxane nonionic wetting and dispersing agent, and 40 parts by mass of deionized water were added sequentially to a reaction vessel. The mixture was stirred at room temperature for 45 min, and the pH was adjusted to 6.0~7.0 with ammonia water. After filtration, the working solution of the fluorine-free oil-repellent and stain-resistant fabric finishing agent was obtained.

[0067] Example 2 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is the same as in Example 1, the only difference being: step (3) is: 42 parts by mass of the POSS / PDMS side-chain modified acrylate copolymer emulsion obtained in step (1), 12 parts by mass of the reactive re-entrant microgel dispersion obtained in step (2), 4 parts by mass of caprolactam-blocked HDI trimer water-dispersible crosslinking agent, 0.8 parts by mass of polyether-modified polysiloxane nonionic wetting and dispersing agent, and 40 parts by mass of deionized water were added sequentially into a reaction vessel. The mixture was stirred at room temperature for 45 min, and the pH was adjusted to 6.0~7.0 with ammonia water. After filtration, the working solution of the fluorine-free oil-repellent and stain-resistant fabric finishing agent was obtained.

[0068] Example 3 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is the same as in Example 1, the only difference being: step (3) is: 48 parts by mass of the POSS / PDMS side-chain modified acrylate copolymer emulsion obtained in step (1), 16 parts by mass of the reactive re-entrant microgel dispersion obtained in step (2), 5 parts by mass of caprolactam-blocked HDI trimer water-dispersible crosslinking agent, 0.8 parts by mass of polyether-modified polysiloxane nonionic wetting and dispersing agent, and 40 parts by mass of deionized water were added sequentially into a reaction vessel. The mixture was stirred at room temperature for 45 min, and the pH was adjusted to 6.0~7.0 with ammonia water. After filtration, the working solution of the fluorine-free oil-repellent and stain-resistant fabric finishing agent was obtained.

[0069] Example 4 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is the same as in Example 1, the only difference being: step (3) is: 55 parts by mass of the POSS / PDMS side-chain modified acrylate copolymer emulsion obtained in step (1), 22 parts by mass of the reactive re-entrant microgel dispersion obtained in step (2), 8 parts by mass of caprolactam-blocked HDI trimer water-dispersible crosslinking agent, 0.8 parts by mass of polyether-modified polysiloxane nonionic wetting and dispersing agent, and 40 parts by mass of deionized water were added sequentially to a reaction vessel. The mixture was stirred at room temperature for 45 min, and the pH was adjusted to 6.0~7.0 with ammonia water. After filtration, the working solution of the fluorine-free oil-repellent and stain-resistant fabric finishing agent was obtained.

[0070] Example 5 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is the same as in Example 1, the only difference being: step (3) is: 60 parts by mass of the POSS / PDMS side-chain modified acrylate copolymer emulsion obtained in step (1), 25 parts by mass of the reactive re-entrant microgel dispersion obtained in step (2), 9 parts by mass of caprolactam-blocked HDI trimer water-dispersible crosslinking agent, 0.8 parts by mass of polyether-modified polysiloxane nonionic wetting and dispersing agent, and 40 parts by mass of deionized water were added sequentially into a reaction vessel. The mixture was stirred at room temperature for 45 min, and the pH was adjusted to 6.0~7.0 with ammonia water. After filtration, the working solution of the fluorine-free oil-repellent and stain-resistant fabric finishing agent was obtained.

[0071] Comparative Example 1 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, which is prepared in accordance with Example 1, except that isobutyl methacrylate (POSS) in step (1) is replaced with an equal amount of methyl methacrylate.

[0072] Comparative Example 2 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, which is prepared in accordance with Example 1, except that the methacryloyloxypropyl mono-terminated polydimethylsiloxane in step (1) is replaced with an equal amount of stearyl methacrylate.

[0073] Comparative Example 3 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is the same as in Example 1, the only difference being: step (2) is omitted, and step (3) is: 52 parts by mass of the POSS / PDMS side-chain modified acrylate copolymer emulsion obtained in step (1), 6 parts by mass of caprolactam blocked HDI trimer water-dispersible crosslinking agent, 0.8 parts by mass of polyether modified polysiloxane nonionic wetting and dispersing agent, and 60 parts by mass of deionized water were added sequentially into a reaction vessel. The mixture was stirred at room temperature for 45 min, and the pH was adjusted to 6.0~7.0 with ammonia water. After filtration, the working solution of the fluorine-free oil-repellent and stain-resistant fabric finishing agent was obtained.

[0074] Comparative Example 4 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is the same as in Example 1, the only difference being: step (2) is omitted, and step (3) is: 52 parts by weight of the POSS / PDMS side-chain modified acrylate copolymer emulsion obtained in step (1), 25 parts by weight of a common nano-SiO2 aqueous dispersion with a solid content of 20 wt% (average particle size of about 50 nm), 6 parts by weight of caprolactam-blocked HDI trimer aqueous dispersion crosslinking agent, 0.8 parts by weight of polyether-modified polysiloxane nonionic wetting and dispersing agent, and 35 parts by weight of deionized water were sequentially added to a reaction vessel. The mixture was stirred at room temperature for 45 min, and the pH was adjusted to 6.0-7.0 with ammonia. After filtration, a fluorine-free oil-repellent and stain-resistant fabric finishing agent working solution was obtained. The inorganic solids of common nano-SiO2 added in this example are approximately equal in amount to the inorganic particles contained in the reactive re-entrant microgel in Example 1.

[0075] Comparative Example 5 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is the same as in Example 1, the only difference being: step (3) is: 52 parts by mass of the POSS / PDMS side-chain modified acrylate copolymer emulsion obtained in step (1), 20 parts by mass of the reactive re-entrant microgel dispersion obtained in step (2), 0.8 parts by mass of the polyether modified polysiloxane nonionic wetting and dispersing agent, and 46 parts by mass of deionized water were added sequentially into a reaction vessel. The mixture was stirred at room temperature for 45 min, and the pH was adjusted to 6.0~7.0 with ammonia. The mixture was then filtered to obtain a comparative finishing working solution without crosslinking agent.

[0076] Comparative Example 6 This example provides a fluorine-free oil-repellent and stain-resistant finishing agent, the preparation method of which is the same as in Example 1, except that POSS and PDMS reactive monomers are not involved in copolymerization, but are instead prepared by physical blending. Specifically: First, 18 parts by weight of stearyl methacrylate, 7 parts by weight of hydroxyethyl methacrylate, 6 parts by weight of glycidyl methacrylate, 17 parts by weight of butyl acrylate, 15 parts by weight of methyl methacrylate, 2 parts by weight of methacrylic acid, 2.2 parts by weight of AEO-9, 0.8 parts by weight of sodium dodecyl sulfate, and 120 parts by weight of deionized water were mixed and pre-emulsified. Then, 66 parts by weight of deionized water were added to the reactor, nitrogen was purged for 30 min, and the temperature was raised to 75 °C. The pre-emulsion and a 10 wt% aqueous solution prepared with 0.6 parts by weight of ammonium persulfate were simultaneously added dropwise to the reactor over 3 h. After the addition was completed, the temperature was maintained for another 2 h to obtain a common acrylate emulsion without POSS and PDMS reactive monomers. After cooling to room temperature, 15 parts by weight of isobutyl methacrylate (POSS) and 20 parts by weight of methacryloyloxypropyl monocapped PDMS from Example 1 were added, and the mixture was subjected to high-speed shearing for 20 min without the addition of an initiator to obtain a physical blend emulsion of POSS / PDMS / acrylate.

[0077] Subsequently, 52 parts by mass of the obtained physical blend emulsion, 20 parts by mass of the reactive re-entrant microgel dispersion obtained in step (2) of Example 1, 6 parts by mass of caprolactam-blocked HDI trimer water-dispersible crosslinking agent, 0.8 parts by mass of polyether-modified polysiloxane nonionic wetting and dispersing agent, and 40 parts by mass of deionized water were compounded according to step (3) of Example 1 to obtain the comparative finishing agent.

[0078] Test Example 1 100% cotton fabric was immersed in the working solution (effective solid content 45 g / L) obtained in Example 1, using a two-dip, two-nip process. It was then pre-dried at 100°C for 3 min, baked at 160°C for 2 min, and tested after equilibration at room temperature for 24 h.

[0079] After the polyester textile was subjected to a light alkali reduction treatment, it was subjected to two dips and two nips using the finishing agent working solution obtained in Example 1 with an effective solid content of 40 g / L, pre-dried at 100°C for 2 min, and baked at 155°C for 3 min.

[0080] The nylon fabric was immersed in the finishing agent working solution obtained in Example 1 with an effective solid content of 40 g / L, and then dipped and rubbed twice. It was pre-dried at 95°C for 3 min and then baked at 145°C for 4 min.

[0081] SEM images of cotton fabrics before and after treatment with the finishing agent of Example 1 are shown below. Figure 4 As shown. By Figure 4As shown in Figure a, the surface of unprocessed cotton fibers is generally smooth, with natural grooves visible along the fiber axis, but no obvious particle deposition is observed; Figure 4 As shown in Figure b, after treatment, relatively uniform granular / island-like deposits appear on the fiber surface, forming a micro-nano rough interface. Local particles are tightly bonded to the fiber surface, indicating that the POSS / PDMS copolymer and reactive reentry microgel can be co-deposited and fixed on the fiber surface.

[0082] In addition, the properties of three finished fabrics were tested, including: (1) Water contact angle: A contact angle tester was used. The droplet volume was 5 μL. Five different locations were tested for each sample, and the average value was taken.

[0083] (2) Oil contact angle: Olive oil, corn oil and artificial sebum were used as test solutions, with a droplet volume of 5 μL, and the contact angle was recorded after 30 s.

[0084] (3) Oil repellency rating: The fabric’s resistance to wetting of standard oily test solutions is tested according to AATCC TM118 or ISO 14419; “Oil repellency rating after washing” is still evaluated using the same standard oil system and does not refer to the olive oil contact angle rating.

[0085] (4) Spray water repellency: Spray test according to AATCC TM22 or ISO 4920.

[0086] (5) Wash resistance: Perform household washing or accelerated washing according to ISO 6330 or AATCC 61, and test the contact angle and oil repellency rating after washing.

[0087] (6) Friction resistance: The Martindale method was used to conduct dry friction and test the water contact angle, oil contact angle and oil repellency level after friction.

[0088] (7) Air permeability retention rate: The air permeability before and after finishing is tested using a fabric air permeability tester and calculated as air permeability after finishing / air permeability before finishing × 100%.

[0089] The test results are shown in Table 1 below.

[0090] Table 1

[0091] Test Example 2 To illustrate the impact of various factors on the performance of the finishing agent, 100% cotton fabric was immersed in the working solutions (effective solid content 45 g / L) obtained in Examples 1-5 and Comparative Examples 1-6, using a two-dip, two-nip process. Subsequently, it was pre-dried at 100 °C for 3 min, baked at 160 °C for 2 min, and equilibrated at room temperature for 24 h. Then, the water contact angle, olive oil contact angle, oil repellency, and wash resistance were tested.

[0092] The test results are shown in Table 2.

[0093] Table 2

[0094] As shown in Table 2 above, the finishing agent of the present invention can simultaneously achieve oil repellency, wash resistance, good hand feel, and breathability. Comparison results between the comparative examples and the embodiments indicate that simply improving surface hydrophobicity is insufficient to achieve a stable oil repellency effect. In the finishing agent of the present invention, the reactive side chains of POSS and PDMS are mainly used to reduce surface adhesion, the reactive reentrant microgel is mainly used to construct the oil droplet support structure, and crosslinking with an aqueous crosslinking agent can improve wash fastness.

[0095] The above description, in conjunction with specific embodiments, provides a detailed explanation of the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A fluorine-free oil-repellent fabric finishing agent, characterized in that, The finishing agent comprises the following components in parts by weight: 10-25 parts of POSS / PDMS side-chain modified acrylate copolymer; 3-10 parts of reactive re-entrapment microgel; Crosslinking agent 2-15 parts; 20-120 parts water; The reactive reentry microgel includes a cross-linked microgel soft core and nano-silica bonded to the surface of the cross-linked microgel soft core; the bonding includes covalent bonding via β-hydroxyamine linkages.

2. The fluorine-free oil-repellent fabric finishing agent according to claim 1, characterized in that, The POSS / PDMS side-chain modified acrylate copolymer was prepared by the following steps: The monofunctional (meth)acrylate esterified silsesquioxane, (meth)acrylate monoterminated polydimethylsiloxane, the first (meth)acrylate monomer, and the first emulsifier are mixed and pre-emulsified. An initiator is then added under a protective atmosphere to carry out the first polymerization reaction, thus obtaining the product.

3. The fluorine-free oil-repellent fabric finishing agent according to claim 2, characterized in that, The first (meth)acrylic acid monomer includes C12~C22 long-chain alkyl methacrylates, hydroxyethyl methacrylates, glycidyl methacrylates, butyl acrylates, methyl methacrylates, and (meth)acrylic acid in a mass ratio of 10~30:3~12:2~10:10~30:10~30:0.5~4.

4. The fluorine-free oil-repellent fabric finishing agent according to claim 2, characterized in that, The monofunctional (meth)acrylate esterified silsesquioxane has a mass ratio of (meth)acrylate monoterminated polydimethylsiloxane to the first (meth)acrylate monomer of 8~25:10~30:35~80.

5. The fluorine-free oil-repellent fabric finishing agent according to claim 1, characterized in that, The reactive reentry microgel has a particle size of 150-350 nm; and / or the nano-silica has a particle size of 40-70 nm.

6. The fluorine-free oil-repellent fabric finishing agent according to claim 1, characterized in that, The mass ratio of the cross-linked microgel soft core to the nano-silica is 1:(0.2~0.6).

7. The fluorine-free oil-repellent fabric finishing agent according to claim 1, characterized in that, The reactive reentry microgel was prepared by the following steps: The second (meth)acrylic acid monomer is mixed with the second emulsifier and pre-emulsified. An initiator is added under a protective atmosphere to carry out a second polymerization reaction to obtain an epoxy-containing crosslinked microgel soft core. The epoxy-containing crosslinked microgel soft core is then subjected to a ring-opening reaction with aminated nano-silica to covalently bond the nano-silica to the surface of the crosslinked microgel soft core, thus obtaining the final product.

8. The fluorine-free oil-repellent fabric finishing agent according to claim 7, characterized in that, The second (meth)acrylic monomer includes glycidyl methacrylate, butyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, and ethylene glycol dimethacrylate in a mass ratio of 15~35:20~45:20~45:2~10:0.5~5.

9. The fluorine-free oil-repellent fabric finishing agent according to claim 7, characterized in that, The aminated nano-silica was prepared by the following steps: Prepare an alcohol-water dispersion of nano-silica, add an aminosilane coupling agent, adjust the pH of the system to 8.5-11.0, and react at 55-65 °C for 3-5 h to obtain the final product; The molar mass ratio of the amino group in the aminosilane coupling agent to the silica in the nano-silica is 0.8~1.0 mmol / g.

10. The method for preparing the fluorine-free oil-repellent fabric finishing agent according to any one of claims 1 to 9, characterized in that, Includes the following steps: The POSS / PDMS side-chain modified acrylate copolymer, the reactive re-entrant microgel, the crosslinking agent, and water are mixed and the pH is adjusted to 6.0-7.0 to obtain the final product.

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