Self-corresponding targeted fixed-point selective non-phosphorus decolorization method for yakwool

Abstract

The invention relates to the technical field of yakwool decoloring, in particular to a self-corresponding targeted fixed-point selective non-phosphorus decoloring method for yakwool. According to the method, a self-corresponding targeted fixed-point selective phosphorus-free decolorization process is adopted, and the process comprises the following steps: wool washing and degreasing, self-corresponding targeted fixed-point activation pretreatment, phosphorus-free selective oxidation decolorization, reduction decolorization and softening treatment. The natural pigment in the yakwool fiber is well removed, the whiteness of the yakwool fiber is improved, the decolorization temperature is greatly reduced, the risk of oxidative damage of the yakwool fiber is reduced, and the mechanical property of the decolorized yakwool fiber is improved. Meanwhile, a non-phosphorus substance is used as a stabilizer for oxydol oxidation decoloration, so that the problem of water pollution caused by decoloration of a phosphorus-containing stabilizer is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of yak wool decolorization, in particular to a method for self-targeted, point-selective, phosphorus-free decolorization of yak wool. Background Art

[0002] my country has abundant yak wool resources. Yak wool fiber boasts excellent properties such as lightness, softness, smoothness, elasticity, warmth retention, and good moisture absorption. Yak wool fiber is also relatively affordable compared to cashmere fiber, making it an effective alternative to cashmere and an important textile material. However, most yak wool fibers contain natural pigments such as melanin and tan pigments, which are unevenly distributed. This makes it difficult to produce light or vibrant colors, significantly limiting the development of solid-color yak wool products. To increase the color diversity of yak wool, expand its applications, and enhance its added value, bleaching treatment is necessary. To enrich yak wool with color diversity, expand its applications, and increase its added value, bleaching treatment is necessary. Existing decolorization technologies mostly use phosphorus-containing substances as stabilizers and adopt high-temperature oxidation decolorization with hydrogen peroxide, which can easily destroy the scales on the surface of yak wool fibers and cause serious fiber damage, bringing difficulties to subsequent dyeing and spinning processing. In addition, the use of phosphorus-containing substances as stabilizers leads to high phosphorus content in the wastewater, which can easily cause eutrophication of water bodies, pollute the environment, and cause serious environmental pollution. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a method for self-targeted, selective, phosphorus-free decolorization of yak wool. The present invention analyzes the uneven distribution of natural pigments on yak wool fibers, uses self-targeted, targeted activation and selective oxidative decolorization to remove natural pigments from yak wool fibers, improve the whiteness of yak wool fibers, greatly reduce the decolorization temperature, reduce the risk of oxidative damage to yak wool fibers, and improve the mechanical properties of decolorized yak wool fibers. At the same time, a phosphorus-free substance is used as a stabilizer for hydrogen peroxide oxidative decolorization, avoiding the water pollution problem caused by decolorization with phosphorus-containing stabilizers, and providing an effective, simple, efficient, environmentally friendly, green and sustainable processing technology and method for the decolorization and bleaching of other naturally colored animal fibers. This self-targeted, selective, phosphorus-free optimized decolorization method is simple, easy to implement, environmentally friendly and energy-saving, highly reproducible, and has a long-lasting effect. It provides a new solution for the high-value utilization of yak wool and has good market application prospects.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] The present invention provides a method for selective phosphorus-free decolorization of yak wool by self-targeting and fixed-point selection, comprising the following steps:

[0006] 1) performing a degreasing pretreatment on yak wool and washing the wool with water to obtain defatted yak wool;

[0007] 2) soaking the defatted yak wool obtained in step 1) in a targeted activation treatment solution for targeted activation, and washing the yak wool with water to obtain activated pretreated yak wool;

[0008] The self-targeted activation treatment solution comprises a mixed reagent of isomeric tridecanol polyoxyethylene ether, a mixed reagent of citric acid, a mixed reagent of sodium sulfate, a mixed reagent of ferrous sulfate and a hydrosulfite powder;

[0009] The isomeric tridecanol polyoxyethylene ether mixed reagent contains the following components by weight: 15-20 parts of isomeric tridecanol polyoxyethylene ether, 10-15 parts of isomeric decanol polyoxyethylene ether, 5-10 parts of sodium alkylbenzene sulfonate, 3-5 parts of diethylene glycol monobutyl ether, and 15-20 parts of deionized water;

[0010] The citric acid mixed reagent contains the following components by weight: 5-10 parts of citric acid, 5-10 parts of acetic acid, 10-15 parts of sodium sulfate, and 40-50 parts of deionized water;

[0011] The sodium sulfate mixed reagent contains the following components by weight: 20-30 parts of sodium sulfate, 5-10 parts of sodium alkylbenzene sulfonate, 5-8 parts of ethanol, and 40-50 parts of deionized water;

[0012] The ferrous sulfate mixed reagent contains the following components by weight: 90-95 parts of ferrous sulfate, 2-5 parts of thiourea dioxide, and 3-5 parts of sodium sulfate;

[0013] 3) soaking the activated pretreated yak wool obtained in step 2) in a selective oxidation decolorization solution for selective oxygen bleaching and bleaching, and washing with water to obtain oxygen bleached yak wool;

[0014] The selective oxidation decolorization solution comprises a polymethylaminosiloxane mixed reagent, a diethylenetriamine pentaacetic acid sodium salt mixed reagent, a sodium silicate mixed reagent and hydrogen peroxide;

[0015] The polymethylaminosiloxane mixed reagent contains the following components by weight: 10-15 parts of polymethylaminosiloxane, 3-5 parts of isopropyl alcohol, 5-10 parts of sorbitol, and 20-25 parts of deionized water;

[0016] The diethylenetriamine pentaacetic acid sodium salt mixed reagent contains the following components by weight: 40-50 parts of diethylenetriamine pentaacetic acid sodium salt, 30-40 parts of glutamic acid diacetic acid tetrasodium salt, 5-10 parts of aspartic acid diacetic acid tetrasodium salt, 5-10 parts of sodium polyaspartate, and 10-20 parts of deionized water;

[0017] The sodium silicate mixed reagent contains the following components by weight: 1-5 parts of sodium silicate, 40-50 parts of ethylenediaminetetraacetic acid sodium salt, 30-35 parts of ethylenediaminetetraacetic acid disodium salt, 10-15 parts of sodium citrate, and 1-5 parts of magnesium chloride;

[0018] 4) soaking the oxygen-bleached yak wool in step 3) in a reduction bleaching solution for reduction bleaching, and washing with water to obtain reduction-bleached yak wool;

[0019] 5) Softening the reduction-bleached yak wool obtained in step 4).

[0020] Preferably, the reagent used in the degreasing pretreatment in step 1) is a mixed reagent of isomeric tridecanol polyoxyethylene ether, and the mixed reagent contains the following components by weight: 15-20 parts of isomeric tridecanol polyoxyethylene ether, 10-15 parts of isomeric decanol polyoxyethylene ether, 5-10 parts of sodium alkylbenzene sulfonate, 3-5 parts of diethylene glycol monobutyl ether, and 15-20 parts of deionized water;

[0021] The mass ratio of the yak wool to the isomeric tridecanol polyoxyethylene ether mixed reagent is 100:2.

[0022] Preferably, the conditions for the degreasing pretreatment in step 1) include: temperature of 55° C., time of 30 min, and bath ratio of 1:15.

[0023] Preferably, the conditions for the pretreatment of the site-specific activation from the corresponding target site in step 2) include: soaking for 10 minutes, treating at a temperature of 55° C. for 120 minutes, and a bath ratio of 1:15.

[0024] Preferably, the mass ratio of the defatted yak wool and the mixed reagent of isomeric tridecyl alcohol polyoxyethylene ether in step 2) is 100:1;

[0025] The mass ratio of the defatted yak wool to the citric acid mixed reagent is 100:2;

[0026] The mass ratio of the defatted yak wool to the sodium sulfate mixed reagent is 100:2;

[0027] The mass ratio of the defatted yak wool to the ferrous sulfate mixed reagent is 100:12;

[0028] The mass ratio of the defatted yak wool to the hydrosulfite is 100:3, and the hydrosulfite includes sodium dithionite.

[0029] Preferably, the conditions for the selective oxygen bleaching in step 3) include: soaking for 20 minutes, treating at a temperature of 50-65° C. for 80-140 minutes, and a bath ratio of 1:15.

[0030] Preferably, in step 3), the mass ratio of the activated pretreated yak wool to the polymethylaminosiloxane mixed reagent is 100:2;

[0031] The mass ratio of the activated pretreated yak wool to the diethylenetriamine pentaacetic acid sodium salt mixed reagent is 100:14-20;

[0032] The mass ratio of the activated pretreated yak wool to the sodium silicate mixed reagent is 100:14-20;

[0033] The mass ratio of the activated pretreated yak wool to hydrogen peroxide is 100:100-130.

[0034] Preferably, the reduction decolorization conditions in step 4) include: temperature of 45° C., time of 30 min, and bath ratio of 1:15.

[0035] Preferably, the reducing bleaching solution in step 4) comprises a mixed reagent of polymethylaminosiloxane, a mixed reagent of sodium alkylbenzene sulfonate and hydrosulfite;

[0036] The polymethylaminosiloxane mixed reagent contains the following components by weight: 10-15 parts of polymethylaminosiloxane, 3-5 parts of isopropyl alcohol, 5-10 parts of sorbitol, and 20-25 parts of deionized water;

[0037] The sodium alkylbenzene sulfonate mixed reagent contains the following components by weight: 5-10 parts of sodium alkylbenzene sulfonate, 20-35 parts of isomeric alcohol polyoxyethylene ether, 5-10 parts of ethylene glycol monobutyl ether, and 10-15 parts of deionized water;

[0038] The hydrosulfite includes sodium dithionite;

[0039] The mass ratio of the oxygen bleached yak wool and the polymethylaminosiloxane mixed reagent is 100:2;

[0040] The mass ratio of the oxygen bleaching yak wool and the sodium alkylbenzene sulfonate mixed reagent is 100:2;

[0041] The mass ratio of the oxygen-bleached yak wool to the hydrosulfite is 100:2.

[0042] Preferably, the softening agent used in the softening treatment in step 5) contains the following components by weight: 5-8 parts of polymethylhydrogensiloxane, 5-7 parts of polymethylaminosiloxane, 5-10 parts of sorbitol, and 10-15 parts of deionized water;

[0043] The mass ratio of the reduction-bleached yak wool to the softening agent is 100:2;

[0044] The softening treatment conditions include: temperature of 40° C., time of 20 min, and bath ratio of 1:15.

[0045] Beneficial effects of the present invention:

[0046] The present invention analyzes the uneven distribution of natural pigments on yak wool fibers, adopts auto-targeted fixed-point activation and selective oxidative decolorization to remove natural pigments from yak wool fibers, improve the whiteness of yak wool fibers, greatly reduce the decolorization temperature, reduce the risk of oxidative damage to yak wool fibers, and improve the mechanical properties of decolorized yak wool fibers. At the same time, a phosphorus-free substance is used as a stabilizer for hydrogen peroxide oxidative decolorization, avoiding the water pollution problem caused by decolorization with phosphorus-containing stabilizers, and providing an effective, simple, efficient, environmentally friendly, green and sustainable processing technology and method for the decolorization and bleaching of other natural colored animal fibers. The auto-targeted fixed-point selective phosphorus-free optimized decolorization method is simple, easy to implement, environmentally friendly and energy-saving, highly reproducible, and has a long-lasting effect. It provides a new solution for the high-value utilization of yak wool and has good market application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below.

[0048] Figure 1 The principle of yak wool self-targeted site-selective phosphorus-free oxidation decolorization;

[0049] Figure 2 It is the samples of each stage of yak wool self-targeted selective phosphorus-free decolorization;

[0050] Figure 3 The performance index of yak wool self-targeted site-selective phosphorus-free decolorization sample under optimized conditions;

[0051] Figure 4 SEM images of samples at various stages of yak wool self-targeted, selective, phosphorus-free decolorization;

[0052] Figure 5 Surface element analysis of samples at each stage of yak wool autochromatographic targeted site-selective phosphorus-free decolorization;

[0053] Figure 6 Fourier transform infrared spectra of samples at each stage of yak wool self-targeted site-selective phosphorus-free decolorization;

[0054] Figure 7 XRD patterns of samples at different stages of yak wool self-targeted site-selective phosphorus-free decolorization. DETAILED DESCRIPTION

[0055] The present invention provides a method for selective phosphorus-free decolorization of yak wool by self-targeting and fixed-point selection, comprising the following steps:

[0056] 1) performing a degreasing pretreatment on yak wool and washing the wool with water to obtain defatted yak wool;

[0057] 2) soaking the defatted yak wool obtained in step 1) in a targeted activation treatment solution for targeted activation, and washing the yak wool with water to obtain activated pretreated yak wool;

[0058] The self-targeted activation treatment solution comprises a mixed reagent of isomeric tridecanol polyoxyethylene ether, a mixed reagent of citric acid, a mixed reagent of sodium sulfate, a mixed reagent of ferrous sulfate and a hydrosulfite powder;

[0059] The isomeric tridecanol polyoxyethylene ether mixed reagent contains the following components by weight: 15-20 parts of isomeric tridecanol polyoxyethylene ether, 10-15 parts of isomeric decanol polyoxyethylene ether, 5-10 parts of sodium alkylbenzene sulfonate, 3-5 parts of diethylene glycol monobutyl ether, and 15-20 parts of deionized water;

[0060] The citric acid mixed reagent contains the following components by weight: 5-10 parts of citric acid, 5-10 parts of acetic acid, 10-15 parts of sodium sulfate, and 40-50 parts of deionized water;

[0061] The sodium sulfate mixed reagent contains the following components by weight: 20-30 parts of sodium sulfate, 5-10 parts of sodium alkylbenzene sulfonate, 5-8 parts of ethanol, and 40-50 parts of deionized water;

[0062] The ferrous sulfate mixed reagent contains the following components by weight: 90-95 parts of ferrous sulfate, 2-5% of thiourea dioxide, and 3-5 parts of sodium sulfate;

[0063] 3) soaking the activated pretreated yak wool obtained in step 2) in a selective oxidation decolorization solution for selective oxygen bleaching and bleaching, and washing with water to obtain oxygen bleached yak wool;

[0064] The selective oxidation decolorization solution comprises a polymethylaminosiloxane mixed reagent, a diethylenetriamine pentaacetic acid sodium salt mixed reagent, a sodium silicate mixed reagent and hydrogen peroxide;

[0065] The polymethylaminosiloxane mixed reagent contains the following components by weight: 10-15 parts of polymethylaminosiloxane, 3-5 parts of isopropyl alcohol, 5-10 parts of sorbitol, and 20-25 parts of deionized water;

[0066] The diethylenetriamine pentaacetic acid sodium salt mixed reagent contains the following components by weight: 40-50 parts of diethylenetriamine pentaacetic acid sodium salt, 30-40 parts of glutamic acid diacetic acid tetrasodium salt, 5-10 parts of aspartic acid diacetic acid tetrasodium salt, 5-10 parts of sodium polyaspartate, and 10-20 parts of deionized water;

[0067] The sodium silicate mixed reagent contains the following components by weight: 1-5 parts of sodium silicate, 40-50 parts of ethylenediaminetetraacetic acid sodium salt, 30-35 parts of ethylenediaminetetraacetic acid disodium salt, 10-25% of sodium citrate, and 1-5 parts of magnesium chloride;

[0068] 4) soaking the oxygen-bleached yak wool in step 3) in a reduction bleaching solution for reduction bleaching, and washing with water to obtain reduction-bleached yak wool;

[0069] 5) Softening the reduction-bleached yak wool obtained in step 4).

[0070] The method comprises soaking the obtained defatted yak wool in a self-targeted activation treatment solution for pre-activation at the corresponding target, and washing the pre-activated yak wool with water, wherein the self-targeted activation treatment solution comprises an isomeric tridecanol polyoxyethylene ether mixed reagent, a citric acid mixed reagent, a sodium sulfate mixed reagent, a ferrous sulfate mixed reagent, and a hydrosulfite powder; the isomeric tridecanol polyoxyethylene ether mixed reagent comprises the following components by weight: 15-20 parts of isomeric tridecanol polyoxyethylene ether, 10-15 parts of isomeric decanol polyoxyethylene ether, 5-10 parts of sodium alkylbenzene sulfonate, 3-5 parts of diethylene glycol monobutyl ether, and 15-20 parts of deionized water;

[0071] The citric acid reagent mixture contains the following components by weight: 5-10 parts citric acid, 5-10 parts acetic acid, 10-15 parts sodium sulfate, and 40-50 parts deionized water; the sodium sulfate reagent mixture contains the following components by weight: 20-30 parts sodium sulfate, 5-10 parts sodium alkylbenzene sulfonate, 5-8 parts ethanol, and 40-50 parts deionized water; and the ferrous sulfate reagent mixture contains the following components by weight: 90-95 parts ferrous sulfate, 1-5 parts thiourea dioxide, and 3-5 parts sodium sulfate. In the present invention, the isomeric tridecanol polyoxyethylene ether reagent mixture is preferably sourced from Anhui Yuanqi New Materials Technology Co., Ltd. and is designated Delijing FDL. In the present invention, the citric acid reagent mixture is preferably sourced from Anhui Yuanqi New Materials Technology Co., Ltd. and is designated Deyasu CP. In the present invention, the sodium sulfate reagent mixture is preferably sourced from Anhui Yuanqi New Materials Technology Co., Ltd. and is designated Deliqing FN. In the present invention, the ferrous sulfate reagent mixture is preferably sourced from Anhui Yuanqi New Materials Technology Co., Ltd. and is designated Delisu FS. In the present invention, the conditions for the site-specific activation pretreatment from the corresponding target preferably include: soaking for 10 minutes, then treating at a temperature of 55°C for 120 minutes, with a bath ratio of 1:15. In the present invention, the mass ratio of the defatted yak wool to the isomeric tridecanol polyoxyethylene ether mixed reagent is preferably 100:1; the mass ratio of the defatted yak wool to the citric acid mixed reagent is preferably 100:2; the mass ratio of the defatted yak wool to the sodium sulfate mixed reagent is preferably 100:2; the mass ratio of the defatted yak wool to the ferrous sulfate mixed reagent is preferably 100:12; the mass ratio of the defatted yak wool to the hydrosulfite is 100:3, and the hydrosulfite preferably includes sodium dithionite.

[0072] The invention soaks the activated pretreated yak wool obtained in a selective sample decolorizing solution for selective oxygen bleaching and bleaching, and then washes the yak wool with water to obtain oxygen bleached yak wool; the selective sample decolorizing solution comprises a polymethylaminosiloxane mixed reagent, a diethylenetriamine pentaacetic acid sodium salt mixed reagent, a sodium silicate mixed reagent and hydrogen peroxide; the polymethylaminosiloxane mixed reagent contains the following components by weight: 10-15 parts of polymethylaminosiloxane, 3-5 parts of isopropyl alcohol, 5-10 parts of sorbitol and 20-25 parts of deionized water; The sodium salt mixture of diethylenetriamine pentaacetic acid contains the following components by weight: 40-50 parts sodium salt of diethylenetriamine pentaacetic acid, 30-40 parts tetrasodium salt of glutamic acid diacetic acid, 5-10 parts tetrasodium salt of aspartic acid diacetic acid, 5-10 parts sodium polyaspartate, and 10-20 parts deionized water. The sodium silicate mixture contains the following components by weight: 1-5 parts sodium silicate, 40-50 parts sodium salt of ethylenediaminetetraacetic acid, 35-35 parts disodium salt of ethylenediaminetetraacetic acid, 10-15 parts sodium citrate, and 1-5 parts magnesium chloride. In the present invention, the polymethylaminosiloxane mixture is preferably sourced from Anhui Yuanqi New Materials Technology Co., Ltd., with the model number Dezhu HR. In the present invention, the sodium salt mixture of diethylenetriamine pentaacetic acid is preferably sourced from Anhui Yuanqi New Materials Technology Co., Ltd., with the model number Deliwen SP. In the present invention, the sodium silicate mixture is preferably sourced from Anhui Yuanqi New Materials Technology Co., Ltd., with the model number Deliwen WD-A. In the present invention, the selective oxygen bleaching conditions include: soaking for 20 minutes, then treating at a temperature of 50-65°C for 80-140 minutes, with a bath ratio of 1:15. In the present invention, the mass ratio of the activated pretreated yak wool to the polymethylaminosiloxane mixed reagent is preferably 100:2; the mass ratio of the activated pretreated yak wool to the diethylenetriamine pentaacetic acid sodium salt mixed reagent is preferably 100:14-20; the mass ratio of the activated pretreated yak wool to the sodium silicate mixed reagent is preferably 100:14-20; and the mass ratio of the activated pretreated yak wool to hydrogen peroxide is preferably 100:100-130.

[0073] The present invention soaks oxygen-bleached yak wool in a reduction bleaching solution for reduction bleaching, and then washes the yak wool to obtain reduction bleached yak wool. In the present invention, the reduction bleaching conditions preferably include: a temperature of 45°C, a time of 30 minutes, and a bath ratio of 1:15. In the present invention, the reducing bleaching solution preferably includes a polymethylaminosiloxane mixed reagent, a sodium alkylbenzene sulfonate mixed reagent and a sodium hydrosulfite; the polymethylaminosiloxane mixed reagent preferably contains the following components by mass: 10-15 parts of polymethylaminosiloxane, 3-5 parts of isopropyl alcohol, 5-10 parts of sorbitol, and 20-25 parts of deionized water; the sodium alkylbenzene sulfonate mixed reagent preferably contains the following components by mass: 5-10 parts of sodium alkylbenzene sulfonate, 20-35 parts of isomeric alcohol polyoxyethylene ether, 5-10 parts of ethylene glycol monobutyl ether, and 10-15 parts of deionized water; the sodium hydrosulfite preferably includes sodium dithionite; the mass ratio of the oxygen-bleached yak wool to the polymethylaminosiloxane mixed reagent is preferably 100:2; the mass ratio of the oxygen-bleached yak wool to the sodium alkylbenzene sulfonate mixed reagent is preferably 100:2; the mass ratio of the oxygen-bleached yak wool to the sodium hydrosulfite mixed reagent is preferably 100:2. In the present invention, the polymethylaminosiloxane mixed reagent is preferably derived from Anhui Yuanqi New Material Technology Co., Ltd., and the model is Dezhu HR. In the present invention, the sodium alkylbenzene sulfonate mixed reagent is preferably derived from Anhui Yuanqi New Material Technology Co., Ltd., and the model is Deliqing HW.

[0074] The present invention subjects the obtained reduction-bleached yak wool to a softening treatment. In the present invention, the softening agent used in the softening treatment preferably contains the following components by weight: 5-8 parts polymethylhydrogensiloxane, 5-7 parts polymethylaminosiloxane, 5-10 parts sorbitol, and 10-15 parts deionized water. In the present invention, the mass ratio of the reduction-bleached yak wool to the softening agent is preferably 100:2. In the present invention, the softening treatment conditions preferably include: a temperature of 40°C, a time of 20 minutes, and a bath ratio of 1:15. In the present invention, the softening agent is preferably sourced from Anhui Yuanqi New Materials Technology Co., Ltd., and the product model is Delirou WS.

[0075] In order to further illustrate the present invention, the present invention is described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0076] Example 1

[0077] 1. Experimental method for selective phosphorus-free decolorization of yak wool by self-targeting and fixed-point selective decolorization

[0078] (1) The principle of yak wool self-targeted selective phosphorus-free decolorization is shown in Figure 7 .

[0079] (2) The process of yak wool self-targeted selective phosphorus-free decolorization

[0080] Yak wool washing and degreasing pretreatment → washing (washing at 40°C until clean) → self-targeted fixed-point activation pretreatment (in the self-targeted fixed-point activation treatment solution, add yak wool and soak for 10 minutes, then start heating to 55°C and keep warm for 120 minutes) → washing (washing at 40°C for 6 times, bath ratio 1:50, until clean) → selective oxygen bleaching and decolorization (after yak wool is added to the selective sample decolorization solution and soaked for 20 minutes, start heating to the required temperature T°C and keep warm for tmin) → washing (washing at 40°C for 6 times, bath ratio 1:50, of which 1% (owf) Delisu KPT (biological deoxygenase, Anhui Yuanqi New Material Technology Co., Ltd.) is added to the second washing for 10 minutes, until clean) → reduction decolorization (yak wool is added to the reduction bleaching solution, and the temperature is started to rise to 45°C and kept warm for 30 minutes) → washing (washing at 40°C for 3 times, bath ratio 1:50)) → softening treatment.

[0081] (3) Process formula for the self-targeted, selective, phosphorus-free decolorization of yak wool fibers

[0082] ① Pretreatment of yak wool washing and degreasing

[0083] Table 1 Yak wool washing and degreasing pretreatment reagents and dosage

[0084]

[0085] ②Self-targeted activation treatment

[0086] Table 2 Reagents and dosages for corresponding targeted site activation treatment

[0087]

[0088] ③Selective oxygen bleaching

[0089] Table 3 Selective oxygen bleaching reagents and dosage

[0090]

[0091] ④Reduction bleaching

[0092] Table 4 Reagents and dosages used for reduction bleaching

[0093]

[0094] ⑤Softening treatment

[0095] Table 5 Reagents and dosages for softening

[0096]

[0097] 2. Analysis and discussion of oxygen bleaching results

[0098] Whiteness Determination: According to GB / T17644.1-2008, "Test Methods for Whiteness and Color of Textile Fibers," bleached yak wool fiber samples were laid flat and combed to form a thin, flat, evenly thick, and opaque layer of yak wool fiber. Each sample was tested five times on a whiteness meter at different locations, and the average whiteness value was calculated.

[0099] Single Fiber Strength Measurement: Yak wool fibers, both before and after bleaching, were placed under constant temperature and humidity for 24 hours. The breaking strength of the yak wool fibers was measured using a single fiber strength tester according to the standard FZ T 98009-2011, "Electronic Single Fiber Strength Tester." Test conditions: a clamping distance of 10 mm, a tensile speed of 10 mm / min, and a preload of 0.2 cN. Each fiber was tested 50 times, and the average value was calculated.

[0100] Alkali solubility determination: Alkali solubility determination is performed according to IWTO test method 4-60E. Accurately weigh 2.0g of sample and place it in 100mL of 0.1M NaOH standard solution, and treat it at a constant temperature of 65±5℃ for 60min. Each sample is measured three times and the average value is obtained. Each batch of samples is processed under the same conditions. The sample is filtered using a domestic 2# sand core funnel, and the sand core funnel is subjected to constant weight treatment: first place the sand core funnel in a weighing bottle, then place it in an oven, and bake it at a temperature of 105℃ for 4 hours. The alkali solubility is calculated according to formula (1):

[0101]

[0102] Where: W is the mass of the residual sample (g), G is the moisture content of the sample before treatment (%).

[0103] Yellowing index determination: Take three parallel samples, each 2.0g, comb them evenly, and use Datacolor to test the tristimulus values X, Y, and Z of the samples. Take 8 points for each sample and take the average value. The yellowing index is calculated according to formula (2):

[0104]

[0105] (1) Effect of hydrogen peroxide dosage (corresponding to z in Table 3) on the effect of yak wool auto-targeted selective phosphorus-free oxidation decolorization

[0106] Table 6 shows the effect of hydrogen peroxide dosage z on the selective phosphorus-free oxidative decolorization of yak wool using auto-targeted activation. As shown in Table 6, the whiteness of yak wool significantly improved during selective phosphorus-free oxidative decolorization after auto-targeted activation pretreatment, as the hydrogen peroxide dosage increased. Both the yellowing index and breaking strength decreased, but the breaking strength remained high. Alkali solubility increased, indicating some damage to the yak wool fibers. A hydrogen peroxide dosage of 120% (owf) resulted in a whiteness of 47.76% and a breaking strength of 7.98 cm.

[0107] Table 6 Effect of hydrogen peroxide dosage on the effect of yak wool auto-responsive targeted site-selective phosphorus-free oxidation decolorization

[0108]

[0109]

[0110] (2) Effect of the dosage of phosphorus-free oxygen bleaching stabilizer SP (corresponding to x in Table 3) on the effect of yak wool autochromatographic targeted site-selective phosphorus-free oxidation decolorization

[0111] Table 7 shows the effect of the amount of SP stabilizer (x) on the targeted, site-selective, non-phosphorus-free oxidative decolorization of yak wool. Increasing the amount of SP stabilizer increases whiteness, reaching 47.62% at an 18% (owf) dosage. Even at this level, breaking strength remains high, meeting the requirements of subsequent dyeing and spinning processes.

[0112] Table 7 Effect of the amount of phosphorus-free oxygen bleaching stabilizer SP on the effect of yak wool autochromatographic targeted site-selective phosphorus-free oxidation decolorization

[0113]

[0114] (3) Effect of the amount of phosphorus-free oxygen bleaching stabilizer WD-A (corresponding to y in Table 3) on the effect of yak wool self-targeted selective phosphorus-free oxidation decolorization

[0115] Table 8 shows the effect of the amount of phosphorus-free oxygen bleaching stabilizer WD-A on the effect of yak wool self-targeted selective phosphorus-free oxidation decolorization. As the amount of stabilizer WD-A increases, the whiteness also increases. When the amount is 18% (owf), it reaches 45.44%, and the breaking strength is 7.34 cN, which also remains at a high level.

[0116] Table 8 Effect of the amount of phosphorus-free oxygen bleaching stabilizer WD-A on the effect of yak wool auto-responsive targeted site-selective phosphorus-free oxidation decolorization

[0117]

[0118] (4) Effect of oxygen bleaching temperature (corresponding to T in Table 3) on the effect of targeted site-selective phosphorus-free oxidation decolorization of yak wool

[0119] Table 9 shows the effect of phosphorus-free oxygen bleaching temperature T on the effect of yak wool self-targeted selective phosphorus-free oxidation decolorization. As the treatment temperature increases, the whiteness increases, but the breaking strength tends to decrease.

[0120] Table 9 Effect of oxygen bleaching temperature on the effect of yak wool auto-targeted site-selective phosphorus-free oxidation decolorization

[0121]

[0122] (5) Effect of oxygen bleaching time (corresponding to t in Table 3) on the effect of yak wool autochromatographic targeted site-selective phosphorus-free oxidation decolorization

[0123] Table 10 shows the effect of phosphorus-free oxygen bleaching time t on the effect of yak wool self-targeted selective phosphorus-free oxidation decolorization. As the oxygen bleaching time increases, the whiteness of yak wool increases, but the breaking strength tends to decrease.

[0124] Table 10 Effect of oxygen bleaching time on the effect of yak wool auto-targeted site-selective phosphorus-free oxidation decolorization

[0125]

[0126] 3 Characterization of the effect of yak wool autophagy on targeted site-selective phosphorus-free decolorization

[0127] (1) Figure 1 The actual samples of yak wool raw wool, self-targeted site activation pretreatment sample, phosphorus-free oxygen bleaching sample (stabilizer SP dosage 18% (owf), stabilizer WD-A dosage 16% (owf), hydrogen peroxide dosage 120% (owf), oxygen bleaching temperature 60°C, oxygen bleaching time 120 min) and reduction bleaching sample are shown.

[0128] (2) Figure 2 The images show raw yak wool, a sample pretreated with auto-targeted site-specific activation, a phosphorus-free oxygen-bleached sample (Stabilizer SP dosage 18% (owf), Stabilizer WD-A dosage 16% (owf), hydrogen peroxide dosage 120% (owf), oxygen bleaching temperature 60°C, oxygen bleaching time 120 minutes), and a reduction-bleached sample. It can be seen that the samples bleached with auto-targeted site-specific phosphorus-free selective oxidation and the reduction-bleached sample based on the phosphorus-free selective oxidation bleaching achieved significantly higher whiteness than the original yak wool. Although the breaking strength and alkali solubility decreased slightly, the yellowness index decreased significantly, indicating that this method and process are effective in decolorizing yak wool.

[0129] The following results are also the results under the conditions of steps (1) and (2).

[0130] (3) Fiber length of yak wool fiber after selective phosphorus-free decolorization at the corresponding targeted site

[0131] Table 11 shows the changes in yak wool fiber length before and after bleaching. After selective phosphorus-free oxygen bleaching and reduction bleaching, the average length of yak wool decreased from 53.5 mm to 45.0 mm and 30.2 mm, respectively, with the shortness percentages of yak wool after selective phosphorus-free oxygen bleaching and reduction bleaching being 10.73% and 11.89%, respectively. This indicates that the fiber length of the bleached yak wool decreased and the shortness percentage increased.

[0132] Table 11 Length of yak wool at each stage of bleaching

[0133] sample Raw cashmere samples Activation pretreatment sample Oxidative decolorization samples Reduction of decolorized samples Average length / mm 53.50 50.00 45.00 30.20 Short fiber rate below 20mm / % 5.70 6.80 10.73 11.89

[0134] (4) Surface morphology of yak wool fibers after self-targeted, selective, phosphorus-free decolorization

[0135] Figure 4 The following SEM images of yak wool fibers before and after bleaching are shown. The edges of the original scale layer are relatively clear and smooth, with distinct layers. However, after targeted activation pretreatment, oxidative bleaching, and reduction bleaching, the edge clarity of the scale layer decreases. Etching marks of varying degrees are visible on the surface of both oxidative and reduction bleaching, and some scales show noticeable warping. This is more pronounced after reduction bleaching, indicating that the scales on the yak wool fiber surface have been damaged to varying degrees after oxidative and reduction bleaching.

[0136] (5) Surface element analysis of yak wool fibers at various stages

[0137] Figure 5 The results of elemental analysis on the surface of yak wool fibers are shown. The original, oxidatively bleached, and reduction-bleached yak wool samples all contained only carbon (C), oxygen (O), nitrogen (N), and sulfur (S). This indicates that the yak wool fibers are phosphorus-free after oxidative and reduction bleaching. This also verifies that no phosphorus-containing chemicals were used during the oxidative and reduction bleaching processes, achieving phosphorus-free and environmentally friendly bleaching.

[0138] (5) Infrared spectroscopy analysis of yak wool fibers

[0139] Figure 6 The infrared spectra of yak wool fiber are shown. The infrared spectra of yak wool original sample, self-targeted site activation pretreatment sample, oxidative decolorization sample and reduction decolorization sample have very similar bands, 3461cm -1 The absorption peaks are ν0H and νNH; 2371cm -1 The absorption peak is νCH2, 1647 cm -1The absorption peaks at positions are νC=O (amide I), 1539 cm -1 The absorption peak is νN-H (amide II), 1081 cm -1 The absorption peak at position is νSO3H, which shows the characteristic absorption peak of yak wool fiber protein. From the four infrared spectra, there is no significant change in the infrared spectrum of the fiber before and after bleaching. However, the oxidative bleaching sample and the reduction bleaching sample have a peak at 1081cm -1 ~3000cm -1 The absorption peak intensity between the two groups is weakened, which may be due to the removal of most of the melanin after bleaching, and the weakening of the absorption of the functional groups shared by protein and melanin.

[0140] (6) XRD analysis of yak wool fiber self-responsive targeted site-selective phosphorus-free decolorization

[0141] Figure 7 The XRD patterns of bleached yak wool are shown in Figures (a) and (b) , respectively. The XRD pattern of yak wool sampled after targeted activation of the corresponding yak wool sample was shown. The XRD pattern of yak wool sampled after oxidative bleaching was shown. The XRD pattern of yak wool sampled after reductive bleaching was also shown. The similar bands in the four samples indicate that while the bleaching treatment has sustained some damage to the yak wool fiber, the damage is minimal, and the bleaching treatment has little effect on the fiber's crystalline structure.

[0142] Table 12 shows the X-ray diffraction index and crystallinity index of bleached yak wool. The relative crystallinity indices of yak wool after selective phosphorus-free oxidative bleaching and reductive bleaching were 79.93% and 73.87%, respectively, significantly higher than the 66.13% relative crystallinity index of wool bleached by conventional methods (data source: Li Xiaoxi. Study on Decolorization and Dyeing Properties of Purple Wool [D]. 2014, Xi'an Polytechnic University). This indicates that the macromolecular regularity of yak wool after selective phosphorus-free oxidative bleaching is better than that of yak wool bleached by conventional methods, indicating that yak wool fiber damage is less than that of conventional methods, and that the selective phosphorus-free oxidative bleaching process for yak wool fibers is feasible.

[0143] Table 12 X-ray diffraction index and crystallinity index of yak wool fiber with targeted and site-selective phosphorus-free decolorization

[0144] sample <![CDATA[I9]]> <![CDATA[I 14 ]]> CI / % Relative crystallinity index / % As is 151 73 51.66 100 Activation pretreatment sample 197 98 50.25 97.27 Oxidative decolorization sample 201 118 41.29 79.93 Reduction decolorization sample 228 141 38.16 73.87

[0145] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A method for selective phosphorus-free decolorization of yak wool by self-targeting and fixed-point selection, characterized in that: The following steps are involved: 1) performing a degreasing pretreatment on yak wool and washing the wool with water to obtain defatted yak wool; 2) soaking the defatted yak wool obtained in step 1) in a targeted activation treatment solution for targeted activation, and washing the yak wool with water to obtain activated pretreated yak wool; The self-targeted activation treatment solution comprises a mixed reagent of isomeric tridecanol polyoxyethylene ether, a mixed reagent of citric acid, a mixed reagent of sodium sulfate, a mixed reagent of ferrous sulfate and a hydrosulfite powder; The isomeric tridecanol polyoxyethylene ether mixed reagent contains the following components by weight: 15-20 parts of isomeric tridecanol polyoxyethylene ether, 10-15 parts of isomeric decanol polyoxyethylene ether, 5-10 parts of sodium alkylbenzene sulfonate, 3-5 parts of diethylene glycol monobutyl ether, and 15-20 parts of deionized water; The citric acid mixed reagent contains the following components by weight: 5-10 parts of citric acid, 5-10 parts of acetic acid, 10-15 parts of sodium sulfate, and 40-50 parts of deionized water; The sodium sulfate mixed reagent contains the following components by weight: 20-30 parts of sodium sulfate, 5-10 parts of sodium alkylbenzene sulfonate, 5-8 parts of ethanol, and 40-50 parts of deionized water; The ferrous sulfate mixed reagent contains the following components by weight: 90-95 parts of ferrous sulfate, 1-5 parts of thiourea dioxide, and 3-5 parts of sodium sulfate; 3) soaking the activated pretreated yak wool obtained in step 2) in a selective oxidation decolorization solution for selective oxygen bleaching and bleaching, and washing with water to obtain oxygen bleached yak wool; The selective oxidation decolorization solution comprises a polymethylaminosiloxane mixed reagent, a diethylenetriamine pentaacetic acid sodium salt mixed reagent, a sodium silicate mixed reagent and hydrogen peroxide; The polymethylaminosiloxane mixed reagent contains the following components by weight: 10-15 parts of polymethylaminosiloxane, 3-5 parts of isopropyl alcohol, 5-10 parts of sorbitol, and 20-25 parts of deionized water; The diethylenetriamine pentaacetic acid sodium salt mixed reagent contains the following components by weight: 40-50 parts of diethylenetriamine pentaacetic acid sodium salt, 30-40 parts of glutamic acid diacetic acid tetrasodium salt, 5-10 parts of aspartic acid diacetic acid tetrasodium salt, 5-10 parts of sodium polyaspartate, and 10-20 parts of deionized water; The sodium silicate mixed reagent contains the following components by weight: 1-5 parts of sodium silicate, 40-50 parts of ethylenediaminetetraacetic acid sodium salt, 30-35 parts of ethylenediaminetetraacetic acid disodium salt, 10-15 parts of sodium citrate, and 1-5 parts of magnesium chloride; 4) soaking the oxygen-bleached yak wool in step 3) in a reduction bleaching solution for reduction bleaching, and washing with water to obtain reduction-bleached yak wool; 5) Softening the reduction-bleached yak wool obtained in step 4).

2. The method according to claim 1, characterized in that The reagent used in the degreasing pretreatment in step 1) is a mixed reagent of isotridecyl alcohol polyoxyethylene ether, which contains the following components in percentage by weight: 15-20 parts of isotridecyl alcohol polyoxyethylene ether, 10-15 parts of isotridecyl alcohol polyoxyethylene ether, 5-10 parts of sodium alkylbenzene sulfonate, 3-5 parts of diethylene glycol monobutyl ether, and 15-20 parts of deionized water; The mass ratio of the yak wool to the isomeric tridecanol polyoxyethylene ether mixed reagent is 100:

2.

3. The method according to claim 1, characterized in that The conditions of the degreasing pretreatment in step 1) include: temperature of 55° C., time of 30 min, and bath ratio of 1:

15.

4. The method according to claim 1, wherein The conditions for the pretreatment of the targeted activation at the corresponding target site in step 2) include: soaking for 10 minutes, treating at a temperature of 55° C. for 120 minutes, and a bath ratio of 1:

15.

5. The method according to claim 1, wherein In step 2), the mass ratio of the defatted yak wool to the mixed reagent of isomeric tridecyl alcohol polyoxyethylene ether is 100:1; The mass ratio of the defatted yak wool to the citric acid mixed reagent is 100:2; The mass ratio of the defatted yak wool to the sodium sulfate mixed reagent is 100:2; The mass ratio of the defatted yak wool to the ferrous sulfate mixed reagent is 100:12; The mass ratio of the defatted yak wool to the hydrosulfite is 100:3, and the hydrosulfite includes sodium dithionite.

6. The method according to claim 1, characterized in that The conditions for the selective oxygen bleaching in step 3) include: soaking for 20 minutes, treating at a temperature of 50-65° C. for 80-140 minutes, and a bath ratio of 1:

15.

7. The method according to claim 1, characterized in that In step 3), the mass ratio of the activated pretreated yak wool to the polymethylaminosiloxane mixed reagent is 100:2; The mass ratio of the activated pretreated yak wool to the diethylenetriamine pentaacetic acid sodium salt mixed reagent is 100:14-20; The mass ratio of the activated pretreated yak wool to the sodium silicate mixed reagent is 100:14-20; The mass ratio of the activated pretreated yak wool to hydrogen peroxide is 100:100-130.

8. The method according to claim 1, characterized in that The conditions for the reduction decolorization in step 4) include: temperature of 45° C., time of 30 min, and bath ratio of 1:

15.

9. The method according to claim 1, characterized in that The reduction bleaching solution in step 4 includes a polymethylaminosiloxane mixed reagent, a sodium alkylbenzene sulfonate mixed reagent and a hydrosulfite; The polymethylaminosiloxane mixed reagent contains the following components by weight: 10-15 parts of polymethylaminosiloxane, 3-5 parts of isopropyl alcohol, 5-10 parts of sorbitol, and 20-25 parts of deionized water; The sodium alkylbenzene sulfonate mixed reagent contains the following components by weight: 5-10 parts of sodium alkylbenzene sulfonate, 20-35 parts of isomeric alcohol polyoxyethylene ether, 5-10 parts of ethylene glycol monobutyl ether, and 10-15 parts of deionized water; The hydrosulfite includes sodium dithionite; The mass ratio of the oxygen bleached yak wool and the polymethylaminosiloxane mixed reagent is 100:2; The mass ratio of the oxygen bleaching yak wool and the sodium alkylbenzene sulfonate mixed reagent is 100:2; The mass ratio of the oxygen-bleached yak wool to the hydrosulfite is 100:

2.

10. The method according to claim 1, characterized in that The softening agent used in the step 5) softening treatment contains the following components by weight: 5-8 parts of polymethylhydrogensiloxane, 5-7 parts of polymethylaminosiloxane, 5-10 parts of sorbitol, and 10-15 parts of deionized water; The mass ratio of the reduction-bleached yak wool to the softening agent is 100:2; The softening treatment conditions include: temperature of 40° C., time of 20 min, and bath ratio of 1:15.

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