A cationic modification method of cotton-ramie blended fiber, cationic modified cotton-ramie blended fiber and a dyeing method thereof

Abstract

This invention provides a method for cationic modification of cotton-linen blended fibers, a method for dyeing cationically modified cotton-linen blended fibers, and the field of textile chemical modification and dyeing technology. This invention uses quaternary ammonium salt compounds containing active groups (epoxy groups, halool groups, or ethyleneimine groups) as cationic modifiers and employs an impregnation-pressing process to chemically modify cotton-linen blended fibers. Quaternary ammonium salt cationic groups are covalently grafted onto the molecular chain, causing the surface potential of the modified blended fibers to change from negative to positive. This reduces the charge repulsion between the fibers and anionic dyes, transforming it into attraction, significantly improving the dyeing depth (K / S value). This provides a universal and efficient solution for environmentally friendly dyeing of cotton-linen blended fabrics.

Description

Technical Field

[0001] This invention relates to the field of textile chemical modification and dyeing technology, and in particular to a method for cationic modification of cotton-linen blended fibers, a method for dyeing cationic modified cotton-linen blended fibers, and the dyeing method thereof. Background Technology

[0002] Currently, cationic modification processes are mostly used for pure cotton fabrics, with commonly used cationic modifiers including quaternary ammonium salts and epoxy groups. However, for cotton-linen blends with denser structures and stronger chemical inertness (especially when linen accounts for a high proportion), conventional physical adsorption cationic agents are unstable and easily washed away. Applying the aforementioned quaternary ammonium salt and epoxy group active cationic modifiers to cotton-linen blends still faces the following technical challenges: First, the significant differences in crystallinity and accessibility between cotton and linen fibers lead to uneven modification, easily resulting in color differences during dyeing; second, existing impregnation processes are time-consuming and require high amounts of modifiers, and are mainly designed for pure cotton or jute / cotton systems. Systematic research on efficient impregnation processes for linen / cotton blends is still lacking. Therefore, developing an efficient active cationic modification method suitable for cotton-linen blends has significant technical value. Summary of the Invention

[0003] The purpose of this invention is to provide a cationic modification method for cotton-linen blended fibers, a cationic modified cotton-linen blended fibers and a dyeing method thereof. By improving the dyeing performance of cotton-linen blended fibers through active cationic modification, the dyeing depth (K / S value) can be significantly improved, solving the problem that cellulose fibers such as flax have difficulty dyeing with anionic dyes due to the lack of ionization groups.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for cationic modification of cotton-linen blended fibers, comprising the following steps: The cationic modifier and emulsifier are mixed with water to obtain a modified solution; The cotton-linen blended fibers are placed in the modified liquid and subjected to impregnation and pressing modification treatment to obtain impregnated and pressed fibers. The impregnated fibers are cured to obtain cationic modified cotton-linen blended fibers; The cationic modifier includes at least one of epoxy-containing quaternary ammonium salt compounds, halool-containing quaternary ammonium salt compounds, and ethyleneimine-containing quaternary ammonium salt compounds.

[0005] Preferably, the cationic modifier includes 2,3-epoxypropyltrimethylammonium chloride or 3-chloro-2-hydroxypropyltrimethylammonium chloride.

[0006] Preferably, the concentration of the cationic modifier in the modified solution is 3~24 g / L.

[0007] Preferably, the emulsifier includes at least one of anionic emulsifiers, nonionic emulsifiers, cationic emulsifiers, and amphoteric emulsifiers; the concentration of the emulsifier in the modified solution is 0.05~2.0 g / L.

[0008] Preferably, the ratio of the cotton-linen blended fiber to the modified liquid is 1:40 to 1:60.

[0009] Preferably, the impregnation modification treatment is a three-impregnation and three-press method, and the conditions for each impregnation and press are independent, including: impregnation time of 30 to 120 seconds, rolling mill pressure of 0.2 to 0.6 MPa, and pressure roller linear speed of 5 to 20 m / min; the residual rate after the three impregnations and three presses is 70 to 90%.

[0010] Preferably, the curing temperature is 100~220℃ and the time is 1~10min.

[0011] This invention provides cationic modified cotton and linen blended fibers obtained by the cationic modification method described in the above technical solution.

[0012] This invention provides a dyeing method for cationic modified cotton-linen blended fibers as described in the above technical solution, comprising the following steps: Cationic modified cotton-linen blended fibers were placed in an aqueous solution containing anionic dyes for dyeing to obtain dyed cotton-linen blended fibers.

[0013] Preferably, the anionic dye includes at least one of acid dyes, reactive dyes, and direct dyes; The dyeing conditions include: using 0.5-5% owf of anionic dye, a liquor ratio of 1:10-1:30, adjusting the pH value to 4-11 according to the type of anionic dye; starting dyeing at 30-50℃, increasing the temperature to 70-95℃ at a rate of 1-3℃ / min, and maintaining the temperature for dyeing for 30-90min.

[0014] This invention provides a cationic modification method for cotton-linen blended fibers. Using a quaternary ammonium salt compound containing active groups (epoxy, halool, or ethyleneimine groups) as a cationic modifier, the cotton-linen blended fibers are chemically modified using an impregnation process. This process causes the active groups in the cationic modifier to covalently bond with the hydroxyl groups on the cellulose molecules, thereby covalently grafting quaternary ammonium salt cationic groups onto the molecular chain. This results in a change in the surface potential of the modified blended fiber from negative to positive, reducing the charge repulsion between the fiber and anionic dyes and converting it into attraction, significantly improving the dyeing depth (K / S value). The method provided by this invention, which uses quaternary ammonium salt compounds containing active groups to modify cotton-linen blended fibers, achieves persistent fixation of cationic groups, with significantly better results than traditional unmodified processes, providing a stable and reliable technical approach for high-quality dyeing of textiles.

[0015] This invention addresses the characteristics of dense and chemically inert cotton-linen blended fibers by using an active quaternary ammonium salt compound to modify their covalent bonds. By controlling the concentration of the modifier, baking temperature, and time, the invention achieves the long-term fixation of cationic groups on cotton-linen fibers, thus solving the technical bottleneck of the difficulty in dyeing anionic dyes onto flax components.

[0016] Compared with the prior art, the present invention has the following advantages: Excellent dyeing performance: After modification, the K / S value of cotton and linen blended fibers for anionic dyes is increased by 63.5%, effectively solving the problem of difficult dyeing of linen.

[0017] Significant environmental benefits: The cotton and linen blended fibers modified by this invention have a strong electrostatic adsorption effect on anionic dyes due to the positive charge on their surface, eliminating the need to add alkali agents during the dyeing process (as shown in Examples 1-4), thus reducing the pollutant load on wastewater. Detailed Implementation

[0018] In this invention, unless otherwise specified, the raw materials or reagents required for preparation are all commercially available products well known to those skilled in the art.

[0019] This invention provides a method for cationic modification of cotton-linen blended fibers, comprising the following steps: The cationic modifier and emulsifier are mixed with water to obtain a modified solution; The cotton-linen blended fibers are placed in the modified liquid and subjected to impregnation and pressing modification treatment to obtain impregnated and pressed fibers. The impregnated fibers are cured to obtain cationic modified cotton-linen blended fibers; The cationic modifier includes at least one of epoxy-containing quaternary ammonium salt compounds, halool-containing quaternary ammonium salt compounds, and ethyleneimine-containing quaternary ammonium salt compounds.

[0020] In this invention, the cationic modifier includes at least one of epoxy-containing quaternary ammonium salt compounds, halool-containing quaternary ammonium salt compounds, and ethyleneimine-containing quaternary ammonium salt compounds; when the cationic modifier is two or more of the above, this invention does not have a special limitation on the ratio of different types of cationic modifiers, and any ratio is acceptable.

[0021] In this invention, the epoxy-containing quaternary ammonium salt compound preferably includes 2,3-epoxypropyltrimethylammonium chloride; the halool-containing quaternary ammonium salt compound preferably includes 3-chloro-2-hydroxypropyltrimethylammonium chloride; and the ethyleneimine-containing quaternary ammonium salt compound preferably includes at least one of quaternized polyethyleneimine and polyethyleneimine alkyl salt.

[0022] In this invention, the concentration of the cationic modifier in the modified solution is preferably 3~24 g / L, more preferably 5~20 g / L, and even more preferably 10~15 g / L.

[0023] In this invention, the emulsifier preferably includes at least one of anionic emulsifiers, nonionic emulsifiers, cationic emulsifiers, and amphoteric emulsifiers; the anionic emulsifier is preferably sodium dodecyl sulfate; the nonionic emulsifier is preferably alkylphenol polyoxyethylene ether (OP-10); the cationic emulsifier is preferably hexadecyltrimethylammonium chloride; and the amphoteric emulsifier is preferably dodecyl dimethyl betaine.

[0024] In this invention, the concentration of the emulsifier in the modified liquid is preferably 0.05~2.0 g / L, more preferably 0.1~1.0 g / L, and even more preferably 0.1~0.5 g / L.

[0025] The present invention does not impose any special limitations on the blending ratio and other specifications of the cotton-linen blended fiber; any cotton-linen blended fiber well known in the art can be used.

[0026] In this invention, the preferred liquor ratio of the cotton-linen blended fiber to the modifying solution is 1:40 to 1:60, more preferably 1:45 to 1:50. The liquor ratio described in this invention is the ratio of the total mass of the modifying solution to the mass of the cotton-linen blended fiber.

[0027] In this invention, the preferred method for the impregnation and pressing modification treatment is three-immersion and three-press, with each impregnation and pressing condition independently including: an impregnation time of 30-120 seconds, more preferably 60-100 seconds; a rolling mill pressure of 0.2-0.6 MPa, more preferably 0.4-0.5 MPa; and a roller speed of 5-20 m / min, more preferably 10-15 m / min. The rolled residue after the three-immersion and three-press treatment is preferably 70-90%, more preferably 80-85%. This invention does not impose any special limitations on the specific operation process of the three-immersion and three-press treatment; it can be carried out according to processes and parameters well known in the art.

[0028] In this invention, the curing temperature is preferably 100~220℃, more preferably 120~170℃, and even more preferably 150~160℃, and the curing time is preferably 1~10 min, more preferably 2~3 min. This invention achieves covalent bonding between the active groups in the cationic modifier and the hydroxyl groups on the cellulose molecules through curing.

[0029] This invention provides cationic modified cotton and linen blended fibers obtained by the cationic modification method described in the above technical solution.

[0030] This invention provides a dyeing method for cationic modified cotton-linen blended fibers as described in the above technical solution, comprising the following steps: Cationic modified cotton-linen blended fibers were placed in an aqueous solution containing anionic dyes for dyeing to obtain dyed cotton-linen blended fibers.

[0031] In this invention, the anionic dye preferably includes at least one of acid dyes, reactive dyes, and direct dyes; when the anionic dye is two or more of the above, this invention does not have a special limitation on the ratio of different types of anionic dyes, and can be adjusted according to needs.

[0032] The present invention does not specifically limit the types of acid dyes, reactive dyes and direct dyes, and any corresponding dyes well known in the art can be used; in the embodiments of the present invention, the anionic dye is preferably acid orange.

[0033] In this invention, the preferred dyeing conditions include: an anionic dye dosage of 0.5-5% owf, a liquor ratio of 1:10-1:30, and adjusting the pH value to 4-11 according to the type of anionic dye; starting dyeing at 30-50°C, increasing the temperature to 70-95°C at a rate of 1-3°C / min, and maintaining the temperature for dyeing for 30-90 minutes; this invention preferably uses acetic acid to adjust the pH value.

[0034] In this invention, the dyeing conditions are more preferably as follows: the amount of anionic dye is 2.5~3% owf, the liquor ratio is 1:15~1:25, the pH value is adjusted to 6~10; dyeing starts at 35~45℃, the temperature is increased to 70~85℃ at a heating rate of 2~3℃ / min, and the dyeing is maintained at this temperature for 50~80min.

[0035] This invention provides a complete range of parameters and preferred intervals for dyeing, including detailed parameters such as dyeing start temperature and heating rate, demonstrating the systematic nature and operability of the process.

[0036] This invention extends the dyeing pH range to 4-11, covering the dyeing needs of acid dyes, reactive dyes and direct dyes, demonstrating its versatility for different anionic dyes.

[0037] The present invention uses a smaller bath ratio of 1:10 to 30, which helps to reduce water consumption and wastewater discharge and meets the requirements of clean production.

[0038] The specific embodiments of the present invention are described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0039] Unless otherwise specified, the experimental methods described in the various embodiments of this invention are conventional methods; unless otherwise specified, the raw materials used are all commercially available products, and the proportions are all by mass percentage.

[0040] In the following examples, the cotton / linen blended yarn is sourced from Fuyang Zhongjing (Anhui) New Material Technology Co., Ltd., with a blend ratio of 55% cotton and 45% linen, a yarn count of 30S, and a spinning process of ring spinning.

[0041] Example 1

[0042] Take 5g of 2,3-epoxypropyltrimethylammonium chloride (GTAC) and 0.1g of alkylphenol polyoxyethylene ether (OP-10) emulsifier, dissolve them in deionized water and bring the volume to 1 L, stir evenly to obtain the modified solution; Take cotton / linen blended yarn, control the liquor ratio at 1:45, and immerse the blended yarn in the modified solution three times and press it three times. The conditions for each immersion and press are: immersion time of 60 seconds, press pressure of 0.4 MPa, press roller linear speed of 10 m / min, and the roll-off rate is controlled at 85% to obtain impregnated fiber. The modified fiber was cured in an oven at 150°C for 1 minute to obtain the modified blended fiber.

[0043] The prepared modified blended fiber was placed in an aqueous solution containing acid orange, with a fixed amount of 2.5% owf of acid orange and a liquor ratio of 1:25. The pH was adjusted to 6 with acetic acid. The modified blended fiber was then dyed at 35 ℃, and the temperature was increased to 85 ℃ at a rate of 3 ℃ / min for 80 min. The fiber was then removed, washed with water, and air-dried at room temperature to obtain the dyed blended fiber.

[0044] K / S value test

[0045] Each sample was folded into 4 layers. Testing was performed using a Hunter Lab f spectrophotometer. A higher K / S value indicates better dyeing performance.

[0046] The dyeing K / S value of the dyed blended fiber in Example 1 was measured to be 3.7.

[0047] Example 2

[0048] Take 10g of 2,3-epoxypropyltrimethylammonium chloride (GTAC) and 0.1g of alkylphenol polyoxyethylene ether (OP-10) emulsifier, dissolve them in deionized water and bring the volume to 1 L, stir evenly to obtain the modified solution; Take cotton / linen (55 / 45) blended yarn, control the liquor ratio to 1:45, and immerse the blended yarn in the modified solution three times and press it three times. The conditions for each immersion and press are: immersion time is 60 seconds, padding pressure is 0.4 MPa, pressure roller speed is 10 m / min, and the residual rate is controlled at 85% to obtain impregnated fiber. The impregnated fibers were cured in an oven at 160°C for 2 minutes to obtain modified blended fibers.

[0049] The prepared modified blended fiber was placed in an aqueous solution containing Acid Orange, with a fixed Acid Orange dosage of 2.5% owf and a liquor ratio of 1:25. The pH was adjusted to 6 with acetic acid. The modified blended fiber was then dyed at 35 ℃, and the temperature was increased to 85 ℃ at a rate of 3 ℃ / min for 80 min. After dyeing, the fiber was removed, washed with water, and air-dried at room temperature to obtain the dyed blended fiber. The K / S value of the dyeing was measured and found to be 4.5.

[0050] Example 3

[0051] Take 15 g of 2,3-epoxypropyltrimethylammonium chloride (GTAC) and 0.1 g of alkylphenol polyoxyethylene ether (OP-10) emulsifier, dissolve them in deionized water and make up to 1 L, stir evenly to obtain the modified solution; Take cotton / linen (55 / 45) blended yarn, control the liquor ratio at 1:40, and immerse the blended yarn in the modified solution three times and press it three times. The conditions for each immersion and press are: immersion time is 60 seconds, press pressure is 0.4 MPa, press roller speed is 10 m / min, and the roll-off rate is controlled at 85% to obtain impregnated fiber. The impregnated fibers were cured in an oven at 170°C for 3 minutes to obtain modified blended fibers.

[0052] The prepared modified blended fiber was placed in an aqueous solution containing Acid Orange, with a fixed Acid Orange dosage of 2.5% owf and a liquor ratio of 1:25. The pH was adjusted to 6 with acetic acid. The modified blended fiber was then dyed at 35 ℃, and the temperature was increased to 85 ℃ at a rate of 3 ℃ / min for 80 min. After dyeing, the fiber was removed, washed with water, and air-dried at room temperature to obtain the dyed blended fiber. The K / S value of the dyeing was measured and found to be 5.1.

[0053] Example 4

[0054] Take 10 g of 3-chloro-2-hydroxypropyltrimethylammonium chloride and 0.1 g of alkylphenol polyoxyethylene ether (OP-10) emulsifier, dissolve them in deionized water and make up to 1 L, stir evenly to obtain the modified solution; Take cotton / linen (55 / 45) blended yarn, with a liquor ratio of 1:45, and immerse the blended yarn in the modified solution three times and press it three times. The conditions for each immersion and press are: immersion time of 60 seconds, roller pressure of 0.4 MPa, roller speed of 10 m / min, and the pick-up rate controlled at 85%, to obtain impregnated fiber. The impregnated fibers were cured in an oven at 160°C for 3 minutes to obtain modified blended fibers.

[0055] The prepared modified blended fiber was placed in an aqueous solution containing Acid Orange, with a fixed Acid Orange dosage of 2.5% owf and a liquor ratio of 1:25. The pH was adjusted to 6 with acetic acid. The modified fiber was then dyed at 35 ℃, with the temperature increased to 85 ℃ at a rate of 3 ℃ / min for 80 min. After dyeing, the fiber was removed, washed with water, and air-dried at room temperature to obtain the dyed blended fiber. The K / S value of the dyeing was measured to be 4.7.

[0056] Comparative Example 1

[0057] The cotton-linen blended fabric of the same specifications as in Example 1, without any modification treatment: Dissolve 0.1 g of alkylphenol polyoxyethylene ether (OP-10) emulsifier in deionized water and bring the volume to 1 L. Stir well to obtain the working solution. Take cotton / linen (55 / 45) blended yarn, control the liquor ratio at 1:40, and immerse the yarn three times and press it three times in the working solution. The conditions for each immersion and pressing are: immersion time of 60 seconds, pressing pressure of 0.4 MPa, pressing roller linear speed of 10 m / min, and the residual rate controlled at 85%. The resulting fiber is cured in an oven at 170℃ for 3 minutes to obtain blended fiber.

[0058] The blended fiber was mixed with acid orange, the amount of acid orange was fixed at 2.5% owf, the liquor ratio was 1:25, and the pH was adjusted to 6 with acetic acid. The blended fiber was dyed at 35 ℃, and the temperature was increased to 85 ℃ at a rate of 3 ℃ / min for 80 min. After dyeing, it was removed, washed with water, and air-dried at room temperature to obtain the dyed blended fiber. The K / S value of the dyeing was measured and found to be 3.12.

[0059] As can be seen from the comparison of Examples 1-4 and Comparative Example 1 above, the method of modifying cotton and linen blended fibers with quaternary ammonium salt compounds containing active groups provided by the present invention can achieve the permanent fixation of cationic groups, thereby significantly and persistently improving its dyeing performance, and the effect is significantly better than the unmodified process.

[0060] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for cationic modification of cotton-linen blended fibers, characterized in that, Includes the following steps: The cationic modifier and emulsifier are mixed with water to obtain a modified solution; The cotton-linen blended fibers are placed in the modified liquid and subjected to impregnation and pressing modification treatment to obtain impregnated and pressed fibers. The impregnated fibers are cured to obtain cationic modified cotton-linen blended fibers; The cationic modifier includes at least one of epoxy-containing quaternary ammonium salt compounds, halool-containing quaternary ammonium salt compounds, and ethyleneimine-containing quaternary ammonium salt compounds.

2. The cationic modification method according to claim 1, characterized in that, The cationic modifier includes 2,3-epoxypropyltrimethylammonium chloride or 3-chloro-2-hydroxypropyltrimethylammonium chloride.

3. The cationic modification method according to claim 1, characterized in that, The concentration of the cationic modifier in the modified solution is 3~24 g / L.

4. The cationic modification method according to claim 1, characterized in that, The emulsifier includes at least one of anionic emulsifiers, nonionic emulsifiers, cationic emulsifiers, and amphoteric emulsifiers; the concentration of the emulsifier in the modified solution is 0.05~2.0 g / L.

5. The cationic modification method according to claim 1, characterized in that, The ratio of the cotton-linen blended fiber to the modified liquid is 1:40 to 1:

60.

6. The cationic modification method according to claim 1, characterized in that, The impregnation modification treatment is a three-impregnation and three-press process, with each impregnation and press condition being independent, including: impregnation time of 30 to 120 seconds, rolling mill pressure of 0.2 to 0.6 MPa, and pressure roller linear speed of 5 to 20 m / min; the residual rate after the three impregnations and three presses is 70 to 90%.

7. The cationic modification method according to claim 1, characterized in that, The curing temperature is 100~220℃ and the time is 1~10min.

8. The cationic modified cotton-linen blended fiber obtained by the cationic modification method according to any one of claims 1 to 7.

9. The dyeing method for cationic modified cotton-linen blended fibers according to claim 8, characterized in that, Includes the following steps: Cationic modified cotton-linen blended fibers were placed in an aqueous solution containing anionic dyes for dyeing to obtain dyed cotton-linen blended fibers.

10. The staining method according to claim 9, characterized in that, The anionic dye includes at least one of acid dyes, reactive dyes, and direct dyes; The dyeing conditions include: using 0.5-5% owf of anionic dye, a liquor ratio of 1:10-1:30, adjusting the pH value to 4-11 according to the type of anionic dye; starting dyeing at 30-50℃, increasing the temperature to 70-95℃ at a rate of 1-3℃ / min, and maintaining the temperature for dyeing for 30-90min.