Ultraviolet curing reaction type wool anti-felting finishing agent, preparation method and finishing process

Abstract

The application discloses an ultraviolet curing reaction type wool anti-felting finishing agent, a preparation method and a finishing process, which is a water-based polyurethane containing polyoxyalkylene and alpha-olefin functional groups. The application can achieve the purpose of anti-felting, greatly improves the affinity to wool, and enables the wool to obtain excellent size stability after physical coating and chemical bonding double action, and meets the machine washable requirement. In addition to imparting the wool with the anti-felting performance, the application can obviously improve the wear resistance and anti-pilling performance of the wool. Moreover, high-temperature baking is not needed, the amount of the finishing agent is small, and the influence on the hand feeling is small.

Description

Technical Field

[0001] This invention belongs to the fields of polymers and textile auxiliaries, and particularly relates to the composition and structure of a UV-curable reactive wool anti-felting and shrinkage finishing agent, as well as the preparation method of the UV-curable reactive wool anti-felting and shrinkage finishing agent, and the finishing process of the UV-curable reactive wool anti-felting and shrinkage finishing agent. Background Technology

[0002] Wool is a textile fiber with a typical scaly structure. Wool consists of a scale layer and a cortex layer. The scale layer of wool is composed of a surface scale, an outer scale, and an inner scale. The scale structure on the surface of wool leads to anisotropic friction effects in the fiber. The scale structure is the main factor that causes the fiber to feel. Eliminating the feeling of wool fabrics is of great significance for pure wool worsted fabrics and knitted fabrics. It can not only enable the fabric to obtain true dimensional stability, but also reduce pilling and fuzzing.

[0003] Currently, in actual production, the relatively mature anti-felting finishing process for pure wool fabrics mainly involves altering the morphology of the scales on the surface of wool fibers, limiting the entanglement of wool fibers, and modifying the surface scales to change the directional friction effect, thereby giving the wool fabric anti-shrinkage properties. Broadly speaking, anti-shrinkage technologies can be divided into three categories: physical and chemical subtractive treatments; resin additive treatments; and two-step treatments combining additive and subtractive methods. Specific methods include chlorination, oxidation, resin anti-shrinkage technology, and bio-enzyme technology. The chlorination method typically uses sodium dichloroisocyanurate (DCCA), which can achieve good anti-felting properties and a good hand feel, but the treated fabric is prone to yellowing, significantly affecting the fabric's color and brightness, and the treatment uniformity is poor. Oxidation methods generally employ harsh processing conditions, which can damage the cortex and cause significant harm to the wool. Enzymatic treatments also cause considerable damage to the wool. Resin finishing utilizes polymer deposition on the surface of wool fibers. After drying and setting, it coats the fiber's scale layer, bonding the fibers together. This reduces directional friction on the fiber surface and prevents fiber movement, greatly improving the fabric's dimensional stability and thus preventing felting and shrinkage. Simultaneously, resin finishing also significantly improves the fabric's abrasion resistance and pilling resistance. Thermally reactive polyurethane is the most commonly used resin finishing agent; other types include polyamide-epoxychloropropane resin, polyether, and modified silicone anti-shrinkage resins, among others.

[0004] Chinese patent CN104878604A discloses a method for preparing a cationic waterborne polyurethane wool anti-felting finishing agent. This method involves synthesizing a reactive cationic waterborne polyurethane capped with methyl ethyl ketone oxime or sodium bisulfite and applying it to wool finishing. This significantly improves felting properties, while also enhancing bursting strength, dyeing depth, and color fastness. Overall, the resin finishing effect is good, but only high dosages can meet the anti-felting requirements. However, high dosages often increase wool weight by 5% to 10%, severely affecting the hand feel of the finished product. Summary of the Invention

[0005] The first objective of this invention is to provide a UV-cured reactive wool anti-felting finishing agent that has good anti-felting effect, can significantly improve wool's abrasion resistance and anti-pilling properties, and requires a small dosage.

[0006] The first objective of this invention is achieved by the following technical measures: a UV-curable reactive wool anti-felting finishing agent, characterized in that it is a waterborne polyurethane containing polyoxyalkylene ether and α-ene functional groups.

[0007] Waterborne polyurethane exhibits good adhesion to wool fiber substrates, forming a network of cross-linked polyurethane film on the fiber surface during setting. This effectively limits the interaction between scales, reducing wool felting, while simultaneously improving fiber strength and abrasion resistance. Wool At Protein fibers are chemically composed of more than 20 α-amino acids linked by peptide bonds, hydrogen bonds, and ionic bonds. Disulfide bonds in these amino acids form cross-links between protein molecular chains, creating the different structures of wool. Tricarboxyethylphosphine can form a coordinated covalent bond with an oxygen atom through the lone pair of electrons on the central phosphorus atom, exhibiting selective reducing properties. The disulfide bonds in the structure containing the most cysteine ​​groups in the scales can be reduced to thiol groups by tricarboxyethylphosphine.

[0008] This invention utilizes the aforementioned principles, employing waterborne polyurethane to coat wool, reducing the directional friction effect on the fiber surface and preventing fiber movement, thus achieving anti-felting. Simultaneously, unsaturated α-ene functional groups are introduced into the polyurethane structure. Tricarboxyethylphosphine is used for reduction pretreatment of the wool, reducing disulfide bonds in the wool to thiol groups. The pretreated wool is then cured with UV light using polyurethane containing unsaturated α-ene functional groups, initiating a thiol-ene double bond free radical reaction. This allows the α-ene functional group polyurethane anti-felting agent to chemically bond to the wool fibers, significantly improving the affinity of the polyurethane anti-felting agent for wool. The wool, after both physical coating and chemical bonding, exhibits excellent dimensional stability, meeting machine-washable requirements. In addition to imparting anti-felting properties, this invention also significantly improves wool's abrasion resistance and anti-pilling properties. Furthermore, it eliminates the need for high-temperature baking, requires a small amount of finishing agent, and has minimal impact on the feel of the wool.

[0009] The UV-curable reactive wool anti-felting and shrinkage finishing agent of the present invention is prepared by polyether with two or more functional groups, monomer containing α-ene functional groups, functional small molecule monomer and polyisocyanate through condensation reaction to obtain an aqueous polymer compound, which is then dispersed in water.

[0010] The polyether with two or more functional groups described in this invention is one or a combination of two or more of the following: ethylene glycol, glycerol, or trimethylolpropane with ethylene oxide (EO) and propylene oxide (PO).

[0011] The polyether with two or more functional groups described in this invention has a molecular weight of 1,000-10,000, and the mass fraction of propylene oxide therein is 0-80%.

[0012] The monomer containing the α-ene functional group described in this invention is one or a combination of two of trimethylolpropane monoallyl ether and 3-allyloxy-1,2-propanediol.

[0013] The functional small molecule monomers described in this invention are polyol compounds having two or more hydroxyl groups, or polyamines having two amino groups; or one or more of the following compounds having a single active hydrogen functional group: phenols, oximes, imidazoles, etc.

[0014] The functional small molecule monomers described in this invention are one or more of the following: 1,4-butanediol, ethylene glycol, diethylene glycol, 1,6-hexanediol, glycerol, trimethylolpropane, bis(trimethylolpropane), dimethylolpropionic acid, dimethylolbutyric acid, tartaric acid, diethanolamine, triethanolamine, methyldiethanolamine, and other polyhydroxy compounds; or ethylenediamine, hexamethylenediamine, isofluranediamine, diamine, diethylenetriamine, triethylenetetramine; or phenols, sodium bisulfite, caprolactam, acetone oxime, methyl ethyl ketone oxime, 3,5-dimethylpyrazole, and other compounds containing a single active hydrogen atom.

[0015] The polyisocyanate described in this invention is one or a combination of two or more substances containing two or more isocyanate groups.

[0016] The polyisocyanate described in this invention is one or more combinations of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), polymethylene polyphenyl isocyanate (PAPI), dicyclohexylmethane diisocyanate (H12MDI), phenyl diisocyanate (XDI), tetramethyl-m-phenylenediamine diisocyanate (TMXDI), and trimethyl-1,6-hexamethylene diisocyanate (TMHDI), as well as one or more combinations of the aforementioned diisocyanate dimers, trimers, biuret, carbodiimide-modified, propylene glycol-modified, and trimethylolpropane reaction products and other derivatives.

[0017] The second objective of this invention is to provide a method for preparing the above-mentioned UV-curable reactive wool anti-felting finishing agent.

[0018] The second objective of this invention is achieved through the following technical measures: a method for preparing the above-mentioned UV-curable reactive wool anti-felting finishing agent, characterized in that the polyether and polyisocyanate are reacted to synthesize a prepolymer, and then a monomer containing an α-ene functional group and a functional small molecule monomer are added to the prepolymer for reaction, and deionized water is added after the reaction is completed to obtain the final product.

[0019] To prevent the α-ene functional group from polymerizing during the reaction, a small amount of polymerization inhibitor is added during the synthesis of the prepolymer. The polymerization inhibitor includes, but is not limited to, phenol, p-hydroxyanisole, hydroquinone, or 2-tert-butylhydroquinone, etc.

[0020] The third objective of this invention is to provide a finishing process for the above-mentioned UV-curable reactive wool anti-felting finishing agent.

[0021] The third objective of this invention is achieved through the following technical measures: a finishing process for the above-mentioned UV-cured reactive wool anti-felting finishing agent, characterized by comprising the following steps:

[0022] S1. A pretreatment process is applied to wool fabrics to reduce the disulfide bonds in wool macromolecules to thiol groups.

[0023] S2. The anti-felting shrinkage finishing agent and photoinitiator are impregnated onto the pretreated wool fabric;

[0024] S3. Drying, followed by irradiation with ultraviolet light, triggers a mercapto-alkene double bond free radical reaction, allowing the anti-felting finishing agent to be fixed on the wool fiber through mercapto chemical bonds, thereby giving the wool anti-felting function.

[0025] In step S1 of this invention, tricarboxyethylphosphine is used to reduce the disulfide bonds in the wool macromolecules to mercapto groups. Tricarboxyethylphosphine can form a coordinated covalent bond with the oxygen atom through the lone pair of electrons carried by the central phosphorus atom, exhibiting selective reducing properties. Specifically, the pretreatment process involves adding the degreased and cleaned wool to a solution containing tricarboxyethylphosphine and a penetrant, treating it at 60°C for 2–5 hours, followed by washing and drying. The amount of tricarboxyethylphosphine used is 1–5%, and the amount of penetrant used is 0.5–2%.

[0026] The penetrant described in this invention is a polyoxyethylene ether of linear or isoalkyl alcohols, including but not limited to one or more combinations of isotridecyl polyoxyethylene ether, isoundecanyl polyoxyethylene ether, decanyl polyoxyethylene ether, and isooctyl polyoxyethylene ether.

[0027] In step S2 of this invention, the photoinitiator is benzoin dimethyl ether, and the amount of anti-felting finishing agent is 1-10%, while the amount of benzoin dimethyl ether is 0.1-5% of the anti-felting finishing agent; in step S3, ultraviolet light of 300-400 nm is used for irradiation for 0.5-3 hours.

[0028] Compared with the prior art, the present invention has the following significant effects:

[0029] This invention utilizes waterborne polyurethane to coat wool, reducing directional friction on the fiber surface and preventing fiber movement, thus achieving anti-felting. Simultaneously, this invention introduces unsaturated α-ene functional groups into the polyurethane structure. By pre-treating the wool with tricarboxyethylphosphine, disulfide bonds in the wool are reduced to thiol groups. The pre-treated wool is then cured under ultraviolet light with polyurethane containing unsaturated α-ene functional groups, initiating a thiol-ene double bond free radical reaction. This allows the α-ene functional group polyurethane anti-felting agent to chemically bond to the wool fibers, transforming the traditional physical resin coating into chemical bonding. The finishing process eliminates the need for high-temperature baking, requires less finishing agent, and has minimal impact on the feel. The thiol-ene double bond free radical chemical reaction utilized in this invention is a typical click chemistry reaction, characterized by high reaction rate and high conversion rate, simple and mild reaction conditions, no byproducts, and compliance with atom economy. The treated wool can achieve excellent dimensional stability and meet the requirements for machine washing. In addition to giving the wool anti-felting and anti-shrinkage properties, this invention can also significantly improve the wool's abrasion resistance and anti-pilling properties. Detailed Implementation

[0030] Example 1

[0031] In a three-necked flask equipped with a stirrer and a reflux condenser, 222.2 g of glycerol polyoxyethylene polyoxypropylene ether (molecular weight 3800, PO mass fraction 65%), 77.9 g of polyethylene glycol (molecular weight 2000), 33.65 g of hexamethylene diisocyanate (HDI), 125.6 g of methyl isobutyl ketone, and 0.1 g of dibutyltin dilaurate were added. The mixture was reacted at 70 °C for 4 h. After the free isocyanate content was measured and found to be within the required range, 8.8 g of trimethylolpropane monoallyl ether, 2.4 g of methyl diethanolamine, and 0.02 g of p-hydroxyanisole were added. The mixture was reacted at 70 °C for more than 2 h. After the system was determined to have no residual isocyanate using the di-n-butylamine method, the reaction was terminated. The solvent was removed by vacuum distillation, and deionized water was added to adjust the product solid content to 30%. The pH of the system was adjusted to 3-6 with acetic acid to obtain the waterborne polyurethane wool anti-felting shrinkage finishing agent product.

[0032] Example 2

[0033] In a three-necked flask equipped with a stirrer and a reflux condenser, 267.2 g of trimethylolpropane polyoxyethylene polyoxypropylene ether (molecular weight 5500, PO mass fraction 75%), 65.9 g of polyethylene glycol (molecular weight 2000), 27.6 g of hexamethylene diisocyanate (HDI), 136.6 g of methyl isobutyl ketone, and 0.1 g of dibutyltin dilaurate were added. The mixture was reacted at 70 °C for 4 h. After the free isocyanate content was measured and found to be within the required range, 5.8 g of 3-allyloxy-1,2-propanediol, 2.2 g of dimethylolpropionic acid, and 0.015 g of p-hydroxyanisole were added. The mixture was reacted at 70 °C for more than 2 h. After the system was determined to have no residual isocyanate using the di-n-butylamine method, the reaction was terminated. The solvent was removed by vacuum distillation, and deionized water was added to adjust the product solid content to 30%. The pH of the system was adjusted to 7-10 using triethylamine to obtain the waterborne polyurethane wool anti-felting shrinkage finishing agent product.

[0034] Example 3

[0035] In a three-necked flask equipped with a stirrer and a reflux condenser, 252.9 g of ethylene glycol polyoxyethylene polyoxypropylene ether (molecular weight 3500, PO mass fraction 55%), 48.2 g of polyethylene glycol (molecular weight 1500), 37.6 g of isophorone diisocyanate (IPDI), 128.9 g of methyl isobutyl ketone, and 0.1 g of dibutyltin dilaurate were added. The mixture was reacted at 70 °C for 4 h. After the free isocyanate content was measured and found to be within the required range, 5.6 g of trimethylolpropane monoallyl ether, 2.5 g of trimethylolpropane, and 0.015 g of p-hydroxyanisole were added. The mixture was reacted at 70 °C for more than 2 h. After the system was determined to have no residual isocyanate using the di-n-butylamine method, the reaction was terminated. The solvent was removed by vacuum distillation, and deionized water was added to adjust the solid content of the product to 30%, thus obtaining the waterborne polyurethane wool anti-felting shrinkage finishing agent.

[0036] Example 4

[0037] In a three-necked flask equipped with a stirrer and a reflux condenser, 260.2 g of ethylene glycol polyoxyethylene polyoxypropylene ether (molecular weight 3500, PO mass fraction 81%), 35 g of polyethylene glycol (molecular weight 1000), 36.5 g of isophorone diisocyanate (IPDI), 125.6 g of methyl isobutyl ketone, and 0.1 g of dibutyltin dilaurate were added. The mixture was reacted at 70 °C for 4 h. After the free isocyanate content was measured and found to be within the required range, 5.7 g of 3-allyloxy-1,2-propanediol, 2.1 g of methyl diethanolamine, and 0.02 g of p-hydroxyanisole were added. The mixture was reacted at 70 °C for more than 2 h. After the system was determined to have no residual isocyanate using the di-n-butylamine method, the reaction was terminated. The solvent was removed by vacuum distillation, and deionized water was added to adjust the product solid content to 30%. The pH of the system was adjusted to 3-6 with acetic acid to obtain the waterborne polyurethane wool anti-felting shrinkage finishing agent product.

[0038] Comparative Example 1

[0039] In a three-necked flask equipped with a stirrer and a reflux condenser, 260.2 g of ethylene glycol polyoxyethylene polyoxypropylene ether (molecular weight 3800, PO mass fraction 67%), 35 g of polyethylene glycol (molecular weight 2000), 32.5 g of hexamethylene diisocyanate (HDI), 128.6 g of methyl isobutyl ketone, and 0.1 g of dibutyltin dilaurate were added. The mixture was reacted at 70 °C for 4 h. After the free isocyanate content was measured and found to be within the required range, 2.1 g of neopentyl glycol, 12.1 g of sodium bisulfite, and 0.02 g of p-hydroxyanisole were added. The mixture was reacted at 70 °C for at least 2 h. After the system was determined to have no residual isocyanate using the di-n-butylamine method, the reaction was terminated. The solvent was removed by vacuum distillation, and deionized water was added to adjust the solid content of the product to 30%, thus obtaining the waterborne polyurethane product.

[0040] Comparative Example 2

[0041] In a three-necked flask equipped with a stirrer and a reflux condenser, 266.2 g of trimethylolpropane polyoxyethylene polyoxypropylene ether (molecular weight 5500, PO mass fraction 75%), 65.8 g of polyethylene glycol (molecular weight 2000), 28.5 g of hexamethylene diisocyanate (HDI), 134.6 g of methyl isobutyl ketone, and 0.1 g of dibutyltin dilaurate were added. The mixture was reacted at 70 °C for 4 h. After the free isocyanate content was measured and found to be within the required range, 1.5 g of 1,3-propanediol, 8.2 g of sodium bisulfite, and 0.02 g of p-hydroxyanisole were added. The mixture was reacted at 70 °C for at least 2 h. After the system was determined to have no residual isocyanate using the di-n-butylamine method, the reaction was terminated. The solvent was removed by vacuum distillation, and deionized water was added to adjust the solid content of the product to 30%, thus obtaining the waterborne polyurethane product.

[0042] Application testing methods and results

[0043] Pre-treatment of wool: After degreasing and cleaning, wool is added to a solution containing tricarboxyethylphosphine and isooctanol polyoxyethylene 5 ether. The amount of tricarboxyethylphosphine is 4%, and the amount of isooctanol polyoxyethylene 5 ether is 0.5%. The bath ratio is 1:10. The wool is treated at 60°C for 2 hours, washed with water, dehydrated, and then dried at 60°C.

[0044] Take the above-mentioned pretreated wool sample, and prepare a 30g / L working solution with the water-based polyurethane wool anti-felting finishing agent of Examples 1-4 and benzoin dimethyl ether (2% of the anti-felting finishing agent). Apply the solution to the above-mentioned pretreated wool fabric using a two-dip and two-paste method, dry at 85°C, and then irradiate with 365nm ultraviolet light for 1 hour.

[0045] Take a wool sample after degreasing and cleaning, prepare a working solution of 30 g / L with the water-based polyurethane wool anti-felting shrinkage finishing agent from Comparative Examples 1-2, apply it to the wool fabric using a two-dip and two-paste method, dry at 85°C, and set at 150°C for 3 min.

[0046] According to FZ / T 7009-2012 "Test Method for Dimensional Change Rate of Wool Textile Products after Washing and Feltification" and GB / T 8629—2017 "Home Washing and Drying Procedures for Textile Testing", the effects of blank samples, Examples 1-4 and Comparative Examples 1-2 with different finishing processes on the dimensional stability of wool were tested. The results are shown in Table 1.

[0047] Dimensional stability test results of wool fabrics - area felting shrinkage (%)

[0048]

[0049]

[0050] (Table 1)

[0051] According to GB / T 4802.2-2008 "Textiles - Martindale Method for Pilling Tests", the pilling resistance of wool was tested on blank samples, Examples 1-4 and Comparative Examples 1-2 with different finishing processes. The results are shown in Table 2.

[0052] Anti-pilling properties of wool fabrics

[0053] blank Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 2 4-5 4-5 4-5 4-5 3-4 3-4

[0054] (Table 2)

[0055] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A finishing process for a UV-curable reactive wool anti-felting finishing agent, wherein the UV-curable reactive wool anti-felting finishing agent is a waterborne polyurethane containing polyoxyalkylene ether and α-ene functional groups. The UV-curable reactive wool anti-felting finishing agent is prepared by polycondensation of a polyether with two or more functional groups, a monomer containing an α-ene functional group, a functional small molecule monomer, and a polyisocyanate to obtain an aqueous polymer compound, which is then dispersed in water; the polyether with two or more functional groups is one or a combination of two or more of ethylene glycol, glycerol, or the ring-opening addition product of trimethylolpropane with ethylene oxide and propylene oxide; the monomer containing an α-ene functional group is one or a combination of two of trimethylolpropane monoallyl ether and 3-allyloxy-1,2-propanediol; characterized by including the following steps: S1. A pretreatment process is applied to wool fabrics to reduce the disulfide bonds in wool macromolecules to thiol groups. S2. The anti-felting shrinkage finishing agent and photoinitiator are impregnated onto the pretreated wool fabric; S3. Drying, followed by irradiation with ultraviolet light, triggers a mercapto-alkene double bond free radical reaction, allowing the anti-felting finishing agent to be fixed onto the wool fiber through mercapto chemical bonds.

2. The finishing process according to claim 1, characterized in that: In step S1, tricarboxyethylphosphine is used to reduce the disulfide bonds in the wool macromolecules to mercapto groups. Specifically, the wool after degreasing and cleaning is added to a solution containing tricarboxyethylphosphine and a penetrant, treated at 60°C for 2-5 hours, and then washed and dried. The amount of tricarboxyethylphosphine used is 1-5%, and the amount of penetrant used is 0.5-2%.

3. The finishing process according to claim 1, characterized in that: In step S2, the amount of anti-felting agent is 1-10%, and the amount of photoinitiator is 0.1-5% of the amount of anti-felting agent.

4. The finishing process according to claim 1, characterized in that: In step S2, the photoinitiator is benzoin dimethyl ether.

5. The finishing process according to claim 1, characterized in that: In step S3, ultraviolet light with a wavelength of 300-400 nm is used for irradiation for 0.5-3 hours.

6. The finishing process according to claim 1, characterized in that: The polyether containing two or more functional groups has a molecular weight of 1,000-10,000, and the mass fraction of propylene oxide therein is 0-80%.

7. The finishing process according to claim 6, characterized in that: The functional small molecule monomer is a polyol compound having two or more hydroxyl groups, or a polyamine having two amino groups; or one or more combinations of phenols, oximes and imidazoles.

8. The finishing process according to claim 7, characterized in that: The polyisocyanate is one or a combination of two or more substances containing two or more isocyanate groups.

Images