Preparation method and application of machine-washable pure silk finishing agent

Abstract

The invention provides a preparation method and application of a machine-washable silk broadcloth finishing agent, epoxy-terminated block polyether silicone oil and hexamethylenediamine are mixed, a solvent with the same mass as the epoxy-terminated block polyether silicone oil and the hexamethylenediamine is added, the mixture is heated to react for a period of time, and a first mixed solution in which a first compound is dissolved is obtained; slowly adding the first mixed solution into a cyanuric fluoride solution, adjusting the pH value of a reaction system to 4-6, and stirring for 2-8 hours to obtain a second mixed solution; the temperature of the reaction system is reduced by 30-50 DEG C, a para-ester solution containing para-ester is slowly added into the second mixed solution, the pH is adjusted to 3-7, then stirring is conducted for 2-8 h, and the machine-washable silk broadcloth finishing agent is prepared and contains two fluorine active and vinyl sulfone active groups, and the machine-washable effect of the silk broadcloth is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of real silk, and in particular to a preparation method and application of a machine-washable real silk finishing agent. Background Art

[0002] Silk has a soft luster and a skin-friendly and soft texture. It is a high-end textile fabric that is deeply favored by consumers. In the cleaning and maintenance process of silk, some small silk products such as scarves and underwear are convenient to wash by hand, but large silk products such as home textiles can only be washed by hand, which is not only time-consuming and labor-intensive, but also easy to cause overall unclean cleaning, which greatly reduces consumers' desire to buy. However, during the machine washing process of silk, the silk fibroin will be fibrillated and damaged due to the friction between the fabrics, between the fabrics and the water flow, and between the fabrics and the tube wall, thereby affecting the color, luster and surface morphology of the silk surface, causing fading, gray damage, wrinkles and other phenomena. Silk that has not been specially treated is not suitable for machine washing, which greatly limits the application of silk in large silk fields such as home textiles.

[0003] At present, the research on machine washability of silk mainly focuses on two aspects: On the one hand, by improving the washing machine program or washing method, the cleaning conditions of silk fabrics can be adapted, but it cannot solve the problem from the root; for example, some studies have proposed using ultrasound instead of traditional washing machines to wash silk fabrics. This method can achieve better cleaning effects and a lasting ironing appearance, while reducing the degree of damage to the fabric surface. However, compared with traditional washing machines, ultrasonic washing has a greater impact on the color of the fabric and there is currently no ultrasonic equipment specifically for home washing. Other studies have explored the effect of drum washing parameters on the gloss of silk fabrics by changing washing parameters and analyzing the action rules of different influencing factors. It provides reference suggestions for home washing and home appliance manufacturers in the care of silk fabrics. Improvements to washing machine programs can reduce problems such as damage or color changes caused by washing silk fabrics, but at the same time, the cleaning effect of the fabric is also reduced accordingly, and the machine washability of silk cannot be solved from the root.

[0004] On the other hand, silk fabrics are treated with anti-dust finishing. This method has low equipment requirements and good feasibility, but the difficulty lies in how to achieve better anti-dust effect and keep the color and gloss of silk unchanged as much as possible. At present, the anti-ash damage finishing agent is mainly a chemical cross-linking agent, such as cyanuric chloride and its derivatives, glutaraldehyde and its derivatives, polycarboxylic acids and epoxy compounds. Among them, cyanuric chloride is the main raw material for synthetic silk wool reactive dyes. Its active groups can be combined with amino or hydroxyl groups on silk in the form of covalent cross-linking, which can play a good fixation role and prevent the silk fibers from fibrillating during machine washing, such as breakage and slippage, thereby playing an anti-ash damage effect; for example, patents with publication numbers CN113463386A and CN117188150A both mention the use of cyanuric chloride derivatives as anti-ash damage finishing agents for silk, but they lack the preparation method of the cyanuric chloride derivatives, and may have the disadvantages of high chemical activity, low solubility in water, and easy hydrolysis; although the patent with publication number CN115897233A mentions the synthesis method of cyanuric chloride cross-linking agents, it has few active groups and cannot play a good cross-linking effect on silk. Although these cross-linking agents can have a certain anti-wrinkle and anti-dust effect on silk, the anti-dust effect is not obvious, and the feel and gloss of silk are reduced after finishing. On the other hand, although a double-active group finishing agent can be synthesized using cyanuric chloride and vinyl sulfone, the reaction of vinyl sulfone starts at 60°C, while the reaction temperature of monochlorotriazine is above 90°C. The difference in reaction activity makes the final reaction rate of the mixed double-active group dye low. Summary of the invention

[0005] The object of the present invention is to provide a preparation method and application of a machine-washable silk finishing agent, which contains two fluorine-active groups and vinyl sulfone-active groups, respectively, can react with silk at a high rate at 60°C, and can form a machine-washable silk finishing liquid with a synergistic effect on silk in combination with a bridging agent, thereby achieving a machine-washable effect of silk.

[0006] To achieve the above objectives, the present technical solution provides a method for preparing a machine washable silk finishing agent, comprising the following steps: S1: mixing the terminal epoxy block polyether silicone oil and hexamethylenediamine in a molar ratio of 1:(2-2.1), adding a solvent having the same mass as the terminal epoxy block polyether silicone oil and the hexamethylenediamine, and heating to react for a period of time to obtain a first mixed solution in which the first compound is dissolved; S2: adding cyanuric fluoride to a solvent and maintaining the temperature of the reaction system at 0-5°C to obtain a cyanuric fluoride solution, slowly adding the first mixed solution to the cyanuric fluoride solution, adjusting the pH of the reaction system to 4-6 and stirring for 2-8 hours to obtain a second mixed solution in which the second compound is dissolved, wherein the molar ratio of cyanuric fluoride to the first compound is (2-2.1):1; S3: lowering the temperature of the reaction system by 30-50°C, slowly adding the para-ester solution including the para-ester into the second mixed solution, adjusting the pH to 3-7 and stirring for 2-8 hours to obtain a machine washable silk finishing agent, wherein the molar ratio of the second compound to the para-ester is 1:(2-2.1).

[0007] The structural formula of the machine washable silk finishing agent synthesized in this scheme is: The specific reaction equation for the preparation method of the machine washable silk finishing agent is as follows: Figure 1 shown.

[0008] In step S1, the epoxy group in the terminal epoxy block polyether silicone oil undergoes a ring-opening reaction with the amino group in the hexamethylenediamine. The epoxy group has a high reactivity and can undergo a nucleophilic addition reaction with the amino group, thereby connecting the hexamethylenediamine to the terminal epoxy block polyether silicone oil molecule to form a first compound; in step S2, the fluorine atom in cyanuric fluoride has a high activity and can undergo a substitution reaction with the first compound in the first mixed solution. By controlling the pH and temperature of the reaction system, cyanuric fluoride and the first compound react in a certain proportion and manner to form a second mixed solution; in step S3, the active group in the para-ester reacts with the components in the second mixed solution, and further introduces a vinyl sulfone active group, and finally obtains a machine washable silk finishing agent containing two fluorine active groups and vinyl sulfone active groups. This scheme gradually introduces different chemical groups into the molecular structure through the design of steps S1 to S3, and finally obtains a machine washable silk finishing agent with specific active groups and properties.

[0009] Specifically, in step S1, the solvent is one or more of water, acetone or isopropanol, and the role of the solvent is to provide a uniform reaction environment so that the reactants can fully contact each other.

[0010] In some embodiments, after adding a solvent having the same mass as the terminal epoxy block polyether silicone oil and hexamethylenediamine, the temperature is raised to 70-100° C. and reacted for 3-7 hours. Heating can accelerate the reaction rate and complete the reaction within a reasonable time. After the reaction is completed, a first mixed solution in which the first compound is dissolved is obtained.

[0011] In step S2, the solvent for dissolving cyanuric fluoride is one or more of water, acetone or isopropanol. In addition, the low temperature condition is set in this scheme to control the reactivity of cyanuric fluoride and avoid unnecessary side reactions.

[0012] In some embodiments, the first mixed solution is slowly added to the cyanuric fluoride solution, and the pH of the reaction system is adjusted to 4-6 using an acid binding agent and stirred for 2-8 hours to obtain a second mixed solution, wherein the acid binding agent is one or more of sodium hydroxide, sodium carbonate or sodium bicarbonate. Slowly adding the first mixed solution can make the reaction more stable and avoid excessive local reaction. The pH is adjusted to create an acid-base environment suitable for the reaction and promote the substitution reaction.

[0013] In step S3, an acid-binding agent is used to adjust the pH to 3-7 and then stirred for 2-8 hours, wherein the acid-binding agent is one or more of sodium hydroxide, sodium carbonate or sodium bicarbonate, to obtain a machine-washable silk finishing agent. The pH is adjusted to meet the acid-base conditions of the para-ester reaction, and the reaction is stirred to fully proceed, and finally a machine-washable silk finishing agent is obtained.

[0014] In a second aspect, the present invention provides an application method of a machine washable silk finishing agent, comprising the following steps: The machine washable silk finishing agent and bridging agent prepared in the first aspect are added into water and stirred evenly to obtain a finishing solution, the silk to be treated is added into the finishing solution, wherein the mass ratio of the silk to the finishing solution is 1:(5-30), the temperature is slowly raised to 40-60°C and the pH value is adjusted to 6-10, the temperature is further raised to 60-90°C and reacted for 20-40 min, the silk is washed and dried to obtain machine washable silk.

[0015] In some embodiments, the temperature is raised to 40-60°C at a rate of 1-2°C / min. In this temperature range, the thermal motion of molecules gradually intensifies. For the machine washable silk finishing agent and bridging agent molecules in the finishing liquid, the appropriate temperature can make them diffuse more freely in the water, so as to better contact with the silk fibers. The silk fibers will also expand to a certain extent at this temperature, and the gaps between the fibers will increase, which is conducive to the finishing agent molecules entering the fiber interior, laying the foundation for subsequent reactions. If the temperature is raised too high at the beginning, the finishing agent and bridging agent may react quickly with the surface of the silk, but this reaction may be uneven, and may cause the surface of the silk to overreact, while the inside is not fully treated. The temperature of 40-60°C can start the reaction more gently and ensure the uniformity of the reaction.

[0016] When the temperature rises to 60-90℃, the reaction rate between the fluorine-active and vinyl sulfone-active groups in the machine-washable silk finishing agent and the protein molecules in the silk will be significantly accelerated. The increase in temperature provides enough energy for the reactant molecules to overcome the activation energy barrier of the reaction, thereby promoting the formation of covalent bonds, allowing the finishing agent and bridging agent to be more firmly bound to the silk fiber, achieving the improvement of the performance of the silk and achieving the effect of machine washability.

[0017] In some embodiments, the bridging agent is propylene glycol triglycidyl ether. The addition of triepoxy compounds in the bridging agent propylene glycol triglycidyl ether can further strengthen the cross-linking effect of silk, and synergize with the machine washable finishing agent to better prevent the silk from being damaged by dust during machine washing.

[0018] In some embodiments, the amount of the machine washable finishing agent in the finishing liquid is 2-10% of the mass of the silk, and the amount of the bridging agent glycerol triglycidyl ether is 0.1-5% of the mass of the silk.

[0019] In some embodiments, the silk includes white silk that has been degummed, natural colored silk that has not been degummed, and dyed silk.

[0020] Furthermore, the dyed silk includes silk dyed with reactive dyes, acid dyes and natural dyes.

[0021] Compared with the prior art, this technical solution has the following characteristics and beneficial effects: The machine-washable silk finishing agent synthesized by the present invention contains two fluorine-active and vinylsulfone-active groups, respectively, which can react with silk at a high rate at 60°C. A small amount of use can well cross-link with silk. In addition, more active groups can also react with amino and hydroxyl groups on certain dyes to form a highly diversified cross-linking system, so that the dye and the fiber are more tightly fixed together, preventing the fiber from fibrillating during washing and friction of the silk, and preventing the dye from falling off the fiber. Further, the present invention introduces the end epoxy block polyether silicone oil with soft properties into the structure of the machine-washable silk finishing agent, which reduces the friction between the silk and the machine and each other during the machine washing process, and finally achieves the machine-washable effect of silk through the triple effects of preventing the fibrillation of silk, preventing the dye from falling off, and reducing the friction of silk.

[0022] In addition, the present invention mixes the synthesized machine-washable silk finishing agent and the bridging agent propylene glycol triglycidyl ether into the finishing liquid, and uses them on the silk at the same time. The addition of the triepoxy compound in the bridging agent propylene glycol triglycidyl ether can continue to strengthen the cross-linking effect of the silk, and has a synergistic effect with the machine-washable silk finishing agent, so as to better prevent the silk from being damaged by dust during the machine washing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is the specific reaction equation of the preparation method of the machine washable silk finishing agent of the present scheme. DETAILED DESCRIPTION

[0024] The specific embodiments listed in the present invention are only for the purpose of clearly demonstrating the technical solutions and implementation processes of the invention, and do not constitute a limitation on the implementation methods of the present invention. The practical application and implementation methods of the present invention are not limited to the above contents. Without departing from the core technical concept of the present invention, any equivalent replacement, improvement, change or other implementation methods made according to the disclosure of the present invention shall be covered within the protection scope of the present invention.

[0025] The specific embodiments presented above are for the purpose of facilitating the understanding of the technical solutions and innovations of the present invention. It should be clear that the implementation of the present invention is not limited to the above content, and any other implementation methods obtained by reasonable adjustment, optimization, expansion, etc. based on the principles of the present invention fall within the scope of patent protection of the present invention.

[0026] Embodiment 1 21.6 g of terminal epoxy block polyether silicone oil and 2.32 g of hexamethylenediamine were added to a reactor, and a mixed solution of acetone and water with the same mass as the terminal epoxy block polyether silicone oil and hexamethylenediamine was added, and then the temperature was raised to 80°C for reaction for 5 hours to obtain a first mixed solution containing the first compound; further, 2.7 g of cyanuric fluoride was added to acetone for dissolution, the system temperature was maintained at 0-5°C, cyanuric fluoride was slowly added to the reactor, and then the pH was adjusted to 5 with sodium carbonate, and the reaction mixture was stirred for 6 hours; then the system temperature was lowered to 40°C, 5.62 g of the dissolved para-ester was slowly added, and then the pH was adjusted to 5 with sodium carbonate, and the reaction mixture was stirred for 6 hours to obtain the machine washable finishing agent.

[0027] At room temperature, 0.5 g of a machine washable finishing agent and 0.2 g of a bridging agent, propylene glycol triglycidyl ether, were weighed and added into water and stirred evenly to obtain a finishing solution. Then, 10 g of the silk to be treated was added. The finishing solution was then heated to 50°C at a rate of 1-2°C / min, sodium carbonate was added to adjust the pH value to 8, and then the temperature was raised to 70°C. The reaction was carried out for 30 min, and finally the silk was washed and dried to obtain machine washable silk.

[0028] Blank example Silk raw material dyed with red reactive dyes to be finished.

[0029] Comparative Example 1 The other steps are the same as those in Example 1, except that the bridging agent glycerol triglycidyl ether is not added.

[0030] Comparative Example 2 The other steps are the same as those in Example 1, except that no epoxy-terminated block polyether silicone oil is added to the reaction system.

[0031] Comparative Example 3 The other steps are the same as those in Example 1, except that no para-ester is added to the reaction system.

[0032] Comparative Example 4 The other steps are the same as those in Example 1, except that cyanuric fluoride and para-ester are not added to the reaction system.

[0033] Test example: The silk of the blank example, Example 1, and Comparative Examples 1 to 4 were washed according to the national standard GB / T 3921-2008 "Textiles - Tests for Color Fastness - Color Fastness to Soaping": 5 g / L soap solution, bath ratio 1:50, washing temperature 40°C, washing time 30 min. The silk was washed 10 times, dried, and ironed for subsequent testing.

[0034] Color index test: During machine washing, friction and the use of detergents will affect the color of silk, so the color index before and after washing is used to evaluate the degree of silk dust damage. The color index uses the colorimeter Datacolor 800 to test the K / S value of silk; the YG524 fabric gloss tester is used to test the gloss change of silk according to FZ / T 01097-2006 "Fabric Gloss Test Method"; the visual evaluation of dust damage is carried out in the standard light source color matching light box. The D65 international standard light source is selected and the sample is placed under the light. There are 10 evaluators with normal vision and color vision. Through the initial visual evaluation experimental training, all evaluators are guaranteed to have the same cognition of the sample gloss. During the experiment, the evaluators are in a room with suitable temperature and humidity and no ambient light interference. The eyes are above the sample, the position distance is consistent, and the evaluation is repeated under the same conditions in different time periods. The test data is shown in Table 1 below.

[0035] Table 1 K / S value, glossiness and visual ash damage of silk before and after washing .

[0036] As can be seen from Table 1, the blank example without anti-dust damage finishing and the comparative example 4 finished with a finishing agent without any active group have obvious color changes after 10 washes, the glossiness is significantly reduced, and a large amount of dust damage occurs; the comparative example 1 finished without adding a bridging agent propylene triglycidyl ether, the comparative example 2 without adding a terminal epoxy block polyether silicone oil reaction in the reaction system, and the comparative example 3 finished with a single fluorine-containing active group finishing agent have slight color changes after 10 washes, the glossiness is reduced, and a small amount of dust damage occurs; and the embodiment 1 of the present invention has no obvious color change after 10 washes, the glossiness change is very small, and no obvious dust damage occurs. Therefore, the preparation and application method of a machine washable silk finishing agent involved in the present invention can effectively protect the silk during the machine washing process of the silk to prevent the silk from generating dust damage, and the silk produced by the present invention can be used for machine washing without affecting the wearing performance of the silk.

[0037] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for preparing a machine washable silk finishing agent, characterized in that: The following steps are involved: S1: mixing the terminal epoxy block polyether silicone oil and hexamethylenediamine in a molar ratio of 1:(2-2.1), adding a solvent having the same mass as the terminal epoxy block polyether silicone oil and the hexamethylenediamine, and heating to react for a period of time to obtain a first mixed solution in which the first compound is dissolved; S2: adding cyanuric fluoride to a solvent and maintaining the temperature of the reaction system at 0-5°C to obtain a cyanuric fluoride solution, slowly adding the first mixed solution to the cyanuric fluoride solution, adjusting the pH of the reaction system to 4-6 and stirring for 2-8 hours to obtain a second mixed solution in which the second compound is dissolved, wherein the molar ratio of cyanuric fluoride to the first compound is (2-2.1):1; S3: lowering the temperature of the reaction system to 30-50°C, slowly adding the para-ester solution including the para-ester into the second mixed solution, adjusting the pH to 3-7 and stirring for 2-8 hours to obtain a machine washable silk finishing agent, wherein the molar ratio of the second compound to the para-ester is 1:(2-2.1).

2. The method for preparing the machine washable silk finishing agent according to claim 1, characterized in that: The structural formula of synthetic machine washable silk finishing agent is: 。 3. The method for preparing the machine washable silk finishing agent according to claim 1, characterized in that: In step S1 and step S2, the solvent is one or more of water, acetone or isopropanol.

4. The method for preparing the machine washable silk finishing agent according to claim 1, characterized in that: The acid binding agent is one or more of sodium hydroxide, sodium carbonate or sodium bicarbonate.

5. The method for preparing the machine washable silk finishing agent according to claim 1, characterized in that: In step S1, after adding a solvent having the same mass as the terminal epoxy block polyether silicone oil and hexamethylenediamine, the temperature is raised to 70-100° C. and reacted for 3-7 hours.

6. An application method of a machine washable silk finishing agent, characterized in that: The following steps are involved: The machine washable silk finishing agent and the bridging agent prepared by the preparation method of the machine washable silk finishing agent according to any one of claims 1 to 5 are added to water and stirred evenly to obtain a finishing liquid, the silk to be treated is added to the finishing liquid, wherein the mass ratio of the silk to the finishing liquid is 1: (5-30), the temperature is slowly raised to 40-60°C and the pH value is adjusted to 6-10, the temperature is further raised to 60-90°C and reacted for 20-40 min, the silk is washed and dried to obtain machine washable silk.

7. The application method of the machine washable silk finishing agent according to claim 6, characterized in that: Raise the temperature to 40~60℃ at a rate of 1~2℃ / min.

8. The application method of the machine washable silk finishing agent according to claim 6, characterized in that: The bridging agent is glycerol triglycidyl ether.

9. The application method of the machine washable silk finishing agent according to claim 6, characterized in that: The amount of the machine washable finishing agent in the finishing liquid is 2-10% of the mass of the silk, and the amount of the bridging agent propylene triglycidyl ether is 0.1-5% of the mass of the silk.

10. The application method of the machine washable silk finishing agent according to claim 6, characterized in that: Real silk includes degummed white silk, undegummed natural colored silk and dyed silk, among which the dyed silk includes silk dyed with reactive dyes, acid dyes and natural dyes.

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