DES and cellulase combined cotton fabric low-strength-loss modification finishing method

Abstract

A DES and cellulase combined cotton fabric low-strength-loss modification finishing method is characterized by comprising the following steps that a buffer solution and a DES solvent are mixed and subjected to ultrasonic treatment, DES / buffer solution is prepared, and the DES solvent is one of a neutral DES solvent, an acidic DES solvent and an alkaline DES solvent; the method comprises the following steps: immersing a cotton fabric into a DES / buffer solution, adding a cellulase preparation, carrying out biological enzyme modification finishing, and carrying out water bath high-temperature inactivation, washing and drying on the obtained cotton fabric. The deep-eutectic solvent is combined with cellulase to carry out one-bath biological enzyme modification finishing on the cotton fabric, so that short fibers and hairiness on the surface of the fabric are removed, the fuzzing and pilling resistance is improved, the method is mild and efficient, and the strength loss rate of the fabric is low; compared with single cellulase treatment, the time consumption is shorter, and the strength loss rate is lower; and the adopted DES solvent is low in cost, biodegradable and recyclable, and meets the production requirements of environmental protection and sustainability.

Description

Technical Field

[0001] The invention relates to a low-strength-loss modification and finishing method for cotton fabrics by combining DES with cellulase, and belongs to the technical field of biological modification of the surface of enzyme-treated cotton fabrics. Background Art

[0002] Cotton is an important variety of natural fiber. It ranks first in the consumer market due to its good moisture absorption and breathability, softness, and easy care. It is the most widely used product in daily life. Its varieties and styles have also been upgraded. It is widely used in various fields such as clothing, bedding, and home decorations. However, in daily wear, due to the mutual friction of fabrics, short fibers on the surface of the fabric are easily broken and pulled out to form pilling, which affects the beauty and comfort of clothing. In order to further improve the softness and comfort of pure cotton fabrics, surface modification finishing (such as polishing, softening, etc.) is adopted for cotton fabrics.

[0003] Due to the wide application of cotton fabrics and the continuous improvement of people's living standards, the wearing comfort of cotton fabrics, especially the tactile comfort of bedding, has become an important topic of basic research and applied research. In recent years, the methods for surface modification and finishing of cotton fabrics are mainly divided into the following methods: physical methods, such as mechanical polishing, ultrasonic finishing, etc.; chemical methods, such as surface coating, softener treatment, etc.; biological methods, such as enzyme modification, etc. Among them, physical and chemical methods are not only complex in process, long in processing cycle, low in production efficiency, high in energy consumption, and the waste chemicals and wastewater produced are difficult to recycle and pollute the environment, but also, the violent mechanical action or the infiltration of chemicals will cause certain damage to the fabric and affect its performance. In contrast, as a green ecological and environmentally friendly substance, bioenzyme has mild catalytic reaction conditions, high efficiency and specificity, can save a lot of energy, and is biodegradable. It has been widely used in textile industry processing in recent years. Using bioenzymes to modify the surface of cotton fabrics can make the treated fabric surface smooth, soft, smooth and delicate, greatly improving the added value of the product. However, while the biological enzyme method is used to break the surface cellulose molecular chains, it will also penetrate into the interior of the fabric, affecting the internal fiber structure of the fabric, causing the overall strength of the fabric to decrease, which will have a great impact on subsequent use. Summary of the invention

[0004]

Technical issues

[0005] When cotton fabrics are modified and finished with bio-enzymes, the surface cellulose molecular chains are broken, and the bio-enzymes also penetrate into the fabric, affecting the internal fiber structure of the fabric, resulting in a decrease in the overall strength of the fabric, which has a great impact on subsequent use. A bio-enzyme modification and finishing method with little damage to the strength of cotton fabrics is urgently needed.

[0006]

Technical solution

[0007] In order to solve the above technical problems, the present invention adopts biodegradable solvent DES combined with cellulase to modify and finish cotton fabric, while ensuring a certain surface polishing or softening effect, the strength loss of the fabric is reduced to meet the subsequent processing requirements.

[0008] The first object of the present invention is to provide a method for low-strength-loss modification and finishing of cotton fabrics by combining DES with cellulase, comprising the following steps:

[0009] (1) Preparation of DES / buffer solution

[0010] The buffer solution is mixed with the DES solvent and subjected to ultrasonic treatment to prepare a DES / buffer solution;

[0011] (2) Enzyme treatment

[0012] The cotton fabric is immersed in a DES / buffer solution, a cellulase preparation is added, and bioenzyme finishing is performed to obtain the finished cotton fabric;

[0013] (3) High temperature inactivation

[0014] The modified cotton fabric is inactivated in a water bath at high temperature, washed and dried to obtain the modified cotton fabric.

[0015] In one embodiment of the present invention, DES is one of a neutral DES solvent, an acidic DES solvent, and a basic DES solvent.

[0016] In one embodiment of the present invention, the preparation method of DES solvent is to mix a hydrogen bond donor and a hydrogen bond acceptor, heat and stir until clear and transparent to obtain DES solvent; the heating and stirring temperature is 80-100° C.; the heating and stirring time is 2-6 hours.

[0017] The hydrogen bond donor is a compound that can provide hydrogen atoms to form hydrogen bonds, usually containing NH or OH bonds. The hydrogen atoms of the hydrogen bond donor can covalently bond with atoms with strong electronegativity to form polar bonds. Due to the attraction of electronegative atoms to electrons, the hydrogen atoms of the hydrogen bond donor carry a partial positive charge, thereby being able to generate electrostatic interactions with lone pairs of electrons in the hydrogen bond acceptor to form hydrogen bonds.

[0018] The hydrogen bond acceptor is a compound or element capable of accepting hydrogen bonds, and usually contains atoms with high electronegativity (such as oxygen, nitrogen or fluorine). These atoms contain lone pairs of electrons and can attract hydrogen atoms in the hydrogen bond donor through electrostatic interaction to form hydrogen bonds.

[0019] In one embodiment of the present invention, the hydrogen bond acceptor of the neutral DES is one of choline chloride and betaine, and the hydrogen bond donor is one of glycerol, polyethylene glycol 200 and polyethylene glycol 600.

[0020] In one embodiment of the present invention, the hydrogen bond acceptor of the acidic DES is one of choline chloride and betaine, and the hydrogen bond donor is one of acetic acid, formic acid and p-toluenesulfonic acid.

[0021] In one embodiment of the present invention, the hydrogen bond acceptor of the alkaline DES is one of choline chloride and betaine, and the hydrogen bond donor is one of urea, ethylene glycol and 1,3-propylene glycol.

[0022] In one embodiment of the present invention, in step (1), the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:2 or 1:5.

[0023] In one embodiment of the present invention, in step (1), the pH of the buffer solution is 4.3 to 6.3.

[0024] In one embodiment of the present invention, in step (1), the pH of the buffer solution is preferably 5.3.

[0025] In one embodiment of the present invention, in step (1), the buffer solution is selected from one of acetic acid-sodium acetate buffer (AA-SA) and citric acid-sodium citrate buffer.

[0026] In one embodiment of the present invention, in step (1), the DES solvent concentration of the DES / buffer solution is 5 to 30 wt %.

[0027] In one embodiment of the present invention, in step (1), ultrasonic treatment is performed until the buffer solution and the DES solvent are uniformly mixed.

[0028] In one embodiment of the present invention, in step (2), the bath ratio (mass ratio) of cotton fabric to DES / buffer solution is 1:8 to 1:14.

[0029] In one embodiment of the present invention, in step (2), the enzyme activity of the cellulase preparation is 500-1000 EGU / g, and the amount of the cellulase preparation is 2-4% owf of the cotton fabric.

[0030] In one embodiment of the present invention, in step (2), the enzyme finishing is carried out at 45-55° C. for 30-60 min.

[0031] In one embodiment of the present invention, in step (2), a high-temperature color test machine is used for bio-enzyme finishing at a rotation speed of 20 to 40 r / min.

[0032] In one embodiment of the present invention, in step (3), the temperature of the water bath high temperature inactivation is 90-100° C., and the treatment time of the water bath high temperature inactivation is 8-20 min.

[0033] The second object of the present invention is to provide modified cotton fabric prepared by the above method.

[0034] The third object of the present invention is to provide application of the modified cotton fabric in the field of textiles.

[0035] In one embodiment of the present invention, the textile field includes clothing and home textiles.

[0036] Beneficial effects:

[0037] (1) The present invention uses a low eutectic solvent (DES) combined with cellulase to perform one-bath bioenzyme modification and finishing on cotton fabric. The preparation method of the low eutectic solvent is simple and low in cost. The prepared low eutectic solvent is biodegradable and recyclable, and has the advantages of being environmentally friendly and sustainable.

[0038] (2) The present invention uses cellulase to catalyze the hydrolysis of cellulose molecular chains on the surface of cotton fabric, thereby breaking the cellulose molecular chains in the fabric and removing the lint and hairiness on the surface of the fabric, thereby improving the anti-pilling ability of cotton while maintaining its own advantageous properties, and improving the softness of the fabric, reducing stiffness, and improving smoothness, thereby improving the feel and style of the fabric, enhancing the tactile comfort, and further improving the wearing performance of the fabric.

[0039] (3) The present invention uses DES combined with cellulase to perform bioenzyme modification and finishing on cotton fabrics. Compared with fabrics treated with a single cellulase, within the same modification and finishing time, the softness of the fabric is more significantly improved, the strength loss rate of the fabric is lower, and it is gentle and efficient.

[0040] (4) The present invention utilizes DES combined with cellulase to modify and finish cotton fabrics in a one-bath process, achieving a softening effect similar to that of a single enzyme treatment for 60 minutes within 30 minutes, while reducing the strength loss rate by about 5%; after 60 minutes of treatment, the strength loss rate of the fabric can be reduced by about 20%. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 The test results of fabric softness and weft strength loss rate of cotton fabrics treated by Example 1, Control Example 1, Control Example 2, Example 2, Control Example 3, and Control Example 4 are shown.

[0042] Figure 2 These are the test results of softness and weft strength loss rate of fabrics treated with different DES types combined with cellulase in Example 1, Example 3, Example 4, Example 5, and Example 6.

[0043] Figure 3 These are the test results of softness and weft strength loss rate of fabrics treated with different DES concentrations combined with cellulase in Examples 1 and 7-9.

[0044] Figure 4The test results of softness and weft strength loss rate of cotton fabrics treated in Examples 1, 10, 11 and Comparative Examples 1, 2, 5, 6 are shown.

[0045] Figure 5 The following are scanning electron microscope images of the fabrics obtained in Example 1, Control Example 1 and Control Example 2; wherein (a) is Control Example 1, (b) is Control Example 2, and (c) is Example 1.

[0046] Figure 6 It is the content of hydrolyzate in the reaction solution of Example 1, Control Example 2, Example 2 and Control Example 4. DETAILED DESCRIPTION

[0047] The fabric raw material used in the examples and comparative examples of the present invention is pure cotton fabric. The cellulase preparation used is selected from Novozymes Celluclast 1.5L cellulase, Novozymes 8000L cellulase, and Genenco CAN neutral cellulase.

[0048] The test method involved in the present invention is:

[0049] 1. Fabric style testing method

[0050] The cotton fabric to be tested was balanced at a temperature of 21±1℃ and a relative humidity of 65±2% for 24h. The cut area was 100cm 2 The circular sample is tested with the PhabrOmeter fabric style meter. A pressure block is attached according to the thickness and mass of the sample. The test is set according to the thickness and surface density of the fabric to obtain the softness, smoothness and stiffness index of the fabric.

[0051] 2. Mechanical properties test of fabric

[0052] The YG(B)02226ET electronic fabric strength tester was used to carry out strength test on the cotton fabric to be tested. The pre-tension was 2N, the initial pulling force was 100N, the sample width was 50mm, the test clamp distance was 200mm, the tensile speed was 100mm / min, each sample was tested 5 times, and the average value was taken as the final result.

[0053] 3. Hydrolysis product release test

[0054] Weigh 250 mg of anhydrous glucose, dissolve in deionized water, and dilute to 250 ml. Take 2.0 ml, 4.0 ml, 6.0 ml, 8.0 ml, and 10.0 ml of this solution and dilute to 50 ml respectively. Then take 2.5 ml of each of the above solutions into test tubes. Add 2.5 ml of 3,5-dinitrosalicylic acid to each and boil for 5 minutes. After cooling, measure the absorbance of the above glucose solutions of different concentrations at 520 nm using a UV spectrophotometer. Draw a standard curve with absorbance and glucose content as the ordinate and abscissa respectively.

[0055] Centrifuge the reaction residue after enzyme inactivation, take 2.0 ml of the supernatant, add 3.0 ml of DNS reagent, boil for 5 min, place in a cold water bath, add deionized water to 25 ml, and use an ultraviolet spectrophotometer to measure its absorbance at a wavelength of 520 nm. Substitute the obtained absorbance value into the standard curve to obtain the corresponding release amount of hydrolysis product (reducing sugar).

[0056] 4. Fabric morphology characterization

[0057] Before the test, the sample was sprayed with gold, and the changes in the surface morphology of the fabric before and after modification were observed using a SU1510 scanning electron microscope. The acceleration voltage during the electron microscope scanning test was 5.0 kV, and the magnifications were 35 times, 900 times, and 2000 times, respectively.

[0058] Example 1

[0059] A method for low-strength-loss modification and finishing of cotton fabric by combining DES with cellulase, comprising the following steps:

[0060] (1) Preparation of DES solvent

[0061] Mix the hydrogen bond donor and hydrogen bond acceptor, heat and stir at 80℃ until clear and transparent, and obtain the neutral DES solvent ChCl-PEG 200 ; The hydrogen bond donor is polyethylene glycol 200, the hydrogen bond acceptor is choline chloride, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:5;

[0062] (2) Preparation of DES / AA-SA solution

[0063] 0.05 M acetic acid-sodium acetate buffer (pH=5.3) was mixed with the prepared DES solvent, and the mixture was shaken and ultrasonicated until the mixture was uniformly mixed to prepare a DES / AA-SA solution with a DES solvent concentration of 20 wt %;

[0064] (3) Enzyme treatment

[0065] The cotton fabric was immersed in a DES / AA-SA solution, the bath ratio of the cotton fabric to the DES / AA-SA solution was 1:10, a 3.0% owf amount of a cellulase preparation (Novozymes Celluclast 1.5L cellulase, 700EGU / g) was added to the cotton fabric, and the fabric was placed in a steel cup of a high-temperature color tester, and the high-temperature color tester was used at 50° C. and a speed of 30 r / min for 30 minutes to perform bioenzyme modification finishing to obtain the finished cotton fabric;

[0066] (4) High temperature sterilization

[0067] The finished cotton fabric was taken out, put into deionized water, inactivated in a water bath at 100°C for 10 min, washed under running water, dried at 60°C to constant weight, and placed in a constant temperature and humidity chamber (21±1°C, 65±2%) for 24 h to obtain modified cotton fabric.

[0068] Comparative Example 1

[0069] (1) Immerse cotton fabric in AA-SA solution with a bath ratio of 1:10 between cotton fabric and AA-SA solvent, place it in a steel cup of a high-temperature color tester, and treat it in a high-temperature color tester at 50°C and 30 r / min for 30 min;

[0070] (2) Take out the cotton fabric prepared in step (1), put it into deionized water, bathe it at 100°C for 10 minutes, wash it under running water, dry it at 60°C to constant weight, and place it in a constant temperature and humidity chamber (21±1°C, 65±2%) for 24 hours.

[0071] Comparative Example 2

[0072] The difference from Example 1 is that steps (1) and (2) are not performed, and the DES / AA-SA solution in step (3) is replaced by 0.05 M acetic acid-sodium acetate buffer (pH=5.3).

[0073] The cotton fabrics obtained in Example 1 and Comparative Examples 1 and 2 were subjected to performance tests, and the test results are as follows:

[0074] Table 1 Test results of weft strength loss rate and style of cotton fabrics obtained in Example 1 and Comparative Examples 1 and 2

[0075] Modified finishing of cotton fabrics Example 1 Comparative Example 1 Comparative Example 2 Fabric weft strength loss rate (%) 15.09 1.59 22.73 Fabric softness 77.15 74.53 76.69 Fabric stiffness 26.38 29.00 27.46 Fabric smoothness 80.76 80.45 80.63

[0076] As can be seen from Table 1, enzyme treatment (Comparative Example 2) improves the softness of the fabric to a certain extent, but further damages the weft strength. After the introduction of DES (Example 1), the structural damage caused by the cellulase entering the fabric is weakened to a certain extent, and the strength loss rate of the fabric is reduced.

[0077] Example 2

[0078] The difference from Example 1 is that in step (3), the reaction time of the enzyme modification finishing is replaced by 60 min instead of 30 min.

[0079] Comparative Example 3

[0080] The difference from the control example 1 is that the high temperature color test machine processing time of 30 minutes is replaced by 60 minutes.

[0081] Comparative Example 4

[0082] The difference from the control example 2 is that the high temperature color test machine processing time of 30 minutes is replaced by 60 minutes.

[0083] The modified cotton fabric obtained was subjected to performance tests, and the test results are as follows:

[0084] Table 2 Test results of weft strength loss rate and style of cotton fabrics obtained in Example 2 and Comparative Examples 3 and 4

[0085] Modified finishing of cotton fabrics Example 2 Comparative Example 3 Comparative Example 4 Fabric weft strength loss rate (%) 20.68 2.16 38.85 Fabric softness 77.73 75.01 77.23 Fabric stiffness 25.91 28.87 25.37 Fabric smoothness 80.92 80.56 80.68

[0086] Compared with Table 1, Table 2 shows that the softening effect of the fabric increases with the increase of treatment time, and the strength loss is also greater. After the introduction of DES, the softening effect similar to that of the single enzyme treatment for 60 minutes can be achieved within 30 minutes, while the strength loss rate of the fabric is greatly reduced.

[0087] Figure 1 The breaking strength loss rate and softness of the cotton fabrics obtained in Example 1, Reference Example 1, Reference Example 2 and Example 2, Reference Example 3, and Reference Example 4 are compared. As can be seen from the figure, the softness of the cotton fabric after enzyme treatment is improved, while the strength loss rate is significantly increased. After the introduction of DES, the softness of the fabric is improved, and the strength loss of the fabric is improved to a certain extent. Within 30 minutes, the strength loss rate is reduced by about 5%, and the modified and finished fabric after the introduction of DES can achieve a softness similar to that of the single enzyme treatment for 60 minutes, and at the same time, the fabric strength loss rate is reduced by nearly 25%. Within 60 minutes, the strength loss rate of the modified and finished cotton fabric treated can also be reduced by about 20%. It can be seen that this method has a certain degree of improvement in the treatment effect.

[0088] Example 3

[0089] A method for low-strength-loss modification and finishing of cotton fabric by combining DES with cellulase, comprising the following steps:

[0090] (1) Preparation of DES solvent

[0091] Mix the hydrogen bond donor and hydrogen bond acceptor, heat and stir at 80℃ until clear and transparent, and obtain the neutral DES solvent ChCl-PEG 600 ; The hydrogen bond donor is polyethylene glycol 600, the hydrogen bond acceptor is choline chloride, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:5;

[0092] (2) Preparation of DES / AA-SA solution

[0093] 0.05 M acetic acid-sodium acetate buffer (pH=5.3) was mixed with the prepared DES solvent, and the mixture was shaken and ultrasonicated until the mixture was uniformly mixed to prepare a DES / AA-SA solution with a DES solvent concentration of 20 wt %;

[0094] (3) Enzyme treatment

[0095] The cotton fabric was immersed in a DES / AA-SA solution, the bath ratio of the cotton fabric to the DES / AA-SA solvent was 1:10, a 3.0% owf amount of a cellulase preparation (Novozymes Celluclast 1.5L cellulase, 700EGU / g) was added to the cotton fabric, and the fabric was placed in a steel cup of a high-temperature color tester, and the high-temperature color tester was used at 50° C. and a speed of 30 r / min for 30 minutes to perform bioenzyme modification finishing to obtain the finished cotton fabric;

[0096] (4) High temperature sterilization

[0097] The finished cotton fabric was taken out, put into deionized water, inactivated in a water bath at 100°C for 10 min, washed under running water, dried at 60°C to constant weight, and placed in a constant temperature and humidity chamber (21±1°C, 65±2%) for 24 h to obtain modified cotton fabric.

[0098] Example 4

[0099] A method for low-strength-loss modification and finishing of cotton fabric by combining DES with cellulase, comprising the following steps:

[0100] (1) Preparation of DES solvent

[0101] The hydrogen bond donor and the hydrogen bond acceptor are mixed, heated and stirred at 80°C until clear and transparent, to obtain a neutral DES solvent Bet-Gly; the hydrogen bond donor is glycerol, the hydrogen bond acceptor is betaine, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:2;

[0102] (2) Preparation of DES / AA-SA solution

[0103] 0.05 M acetic acid-sodium acetate buffer (pH=5.3) was mixed with the prepared DES solvent, and the mixture was shaken and ultrasonicated until the mixture was uniformly mixed to prepare a DES / AA-SA solution with a DES solvent concentration of 20 wt %;

[0104] (3) Enzyme treatment

[0105] The cotton fabric was immersed in a DES / AA-SA solution, the bath ratio of the cotton fabric to the DES / AA-SA solvent was 1:10, a 3.0% owf amount of a cellulase preparation (Novozymes Celluclast 1.5L cellulase, 700 EGU / g) was added to the cotton fabric, and the fabric was placed in a steel cup of a high-temperature color tester, and the high-temperature color tester was used at 50° C. and a speed of 30 r / min for 30 minutes to perform bioenzyme modification finishing, and the finished cotton fabric was obtained;

[0106] (4) High temperature sterilization

[0107] The finished cotton fabric was taken out, put into deionized water, inactivated in a water bath at 100°C for 10 min, washed under running water, dried at 60°C to constant weight, and placed in a constant temperature and humidity chamber (21±1°C, 65±2%) for 24 h to obtain modified cotton fabric.

[0108] Example 5

[0109] The difference from Example 1 is that in step (1), the hydrogen bond donor is replaced with acetic acid to prepare the acidic DES solvent ChCl-AA, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:2.

[0110] Example 6

[0111] The difference from Example 1 is that in step (1), the hydrogen bond donor is replaced with 1,3-propylene glycol to prepare the alkaline DES solvent ChCl-1,3-prop, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:2.

[0112] Table 3 Weft strength loss rate and style test results of cotton fabrics obtained in Example 1 and Examples 3 to 6

[0113] Modified finishing of cotton fabrics Example 1 Example 3 Example 4 Example 5 Example 6 Fabric weft strength loss rate (%) 15.09 20.52 14.98 20.38 18.73 Fabric softness 77.15 76.92 77.10 76.83 77.06 Fabric stiffness 26.38 26.07 27.02 27.11 26.26 Fabric smoothness 80.76 82.28 79.37 80.98 80.77

[0114] As can be seen from Table 3, the use of ChCl-PEG 200 The one-bath bioenzymatic modification and finishing of cotton fabrics using DES solvents prepared by (Example 1) and Bet-Gly (Example 4) has a good softening effect and a low strength loss rate, among which Example 1 has the best effect.

[0115] Figure 2 Comparison of the breaking strength loss and softness of cotton fabrics modified by different DES types combined with cellulase. 200 The comprehensive modification and finishing effect on fabrics is optimal.

[0116] Example 7

[0117] The difference from Example 1 is that in step (2), the DES solvent concentration of the DES / AA-SA solution is replaced by 5 wt % instead of 20 wt %.

[0118] Example 8

[0119] The difference from Example 1 is that in step (2), the DES solvent concentration of the DES / AA-SA solution is replaced by 10 wt % instead of 20 wt %.

[0120] Example 9

[0121] The difference from Example 1 is that in step (2), the DES solvent concentration of the DES / AA-SA solution is replaced by 30 wt % instead of 20 wt %.

[0122] Table 4 Weft strength loss and softness results of cotton fabrics obtained in Examples 1 and 7 to 9

[0123]

[0124]

[0125] It can be seen from Table 4 that with the increase of DES concentration, the strength loss rate of the fabric gradually increases. At a concentration of 20%, the softness of the fabric is greatly improved and the strength loss rate is small. When the concentration is further increased, the softness is not much different but the strength loss rate increases. Therefore, the DES concentration of the DES / AA-SA solution is preferably 20%.

[0126] Figure 3 The figure shows the comparison of the breaking strength loss rate and softness of cotton fabrics modified and finished with different DES concentrations and cellulase. As can be seen from the figure, with the increase of DES concentration, the strength loss rate also gradually increases, and the softness also shows an increasing trend. When the concentration increases from 20% to 30%, the strength loss rate shows a higher growth, while the softness growth rate is slow.

[0127] Example 10

[0128] The difference from Example 1 is that the cellulase preparation Novozymes Celluclast 1.5L cellulase in step (3) is replaced by Novozymes 8000L cellulase.

[0129] Comparative Example 5

[0130] The difference from Control Example 2 is that the cellulase preparation Novozymes Celluclast 1.5L cellulase in step (3) is replaced by Novozymes 8000L cellulase.

[0131] Table 5 Results of weft strength loss and softness of cotton fabrics obtained in Examples 1, 10, Comparative Examples 2, 5

[0132] Modified finishing of cotton fabrics Example 1 Comparative Example 2 Example 10 Comparative Example 5 Fabric weft strength loss rate (%) 15.09 22.73 17.95 20.11 Fabric softness 77.15 76.69 76.21 75.85 Fabric stiffness 26.38 27.46 28.01 28.41 Fabric smoothness 80.76 80.63 80.62 80.22

[0133] It can be seen from Table 5 that although Novozymes 8000L enzyme has less strength damage to the fabric, its modification and finishing effect is also weaker. After the introduction of DES, the synergistic modification and finishing effect of the two is not as good as that of Novozymes 1.5L cellulase. Therefore, Novozymes Celluclast 1.5L cellulase is preferred.

[0134] Embodiment 11

[0135] The difference from Example 1 is that the cellulase preparation Novozymes Celluclast 1.5L cellulase in step (3) is replaced by Genenco CAN neutral cellulase.

[0136] Comparative Example 6

[0137] The difference from Control Example 2 is that the cellulase preparation Novozymes Celluclast 1.5L cellulase in step (3) is replaced by Genencor CAN neutral cellulase.

[0138] Table 6 Results of weft strength loss and softness of cotton fabrics obtained in Examples 1, 11, Comparative Examples 2 and 6

[0139] Modified finishing of cotton fabrics Example 1 Comparative Example 2 Embodiment 11 Comparative Example 6 Fabric weft strength loss rate (%) 15.09 22.73 20.27 26.05 Fabric softness 77.15 76.69 77.25 76.03 Fabric stiffness 26.38 27.46 27.77 28.13 Fabric smoothness 80.76 80.63 80.51 80.38

[0140] As can be seen from Table 6, after the introduction of DES, the softness of Genenco CAN cellulase is greatly improved, but the strength damage to the fabric is still large, and it cannot well balance the improvement of strength and style. Therefore, Novozymes Celluclast 1.5L cellulase is preferred.

[0141] Figure 4 Comparison of the breaking strength loss rate and softness of cotton fabrics modified with different types of cellulase. As can be seen from the figure, after the introduction of DES, the strength loss rate of the fabrics has decreased to a certain extent, and the softness has also improved. Considering both fabric style and strength loss, Novozymes Celluclast 1.5L cellulase has the best improvement effect.

[0142] However, it can be seen that no matter which type of cellulase is used, after the introduction of DES, the modification and finishing effect of cellulase on cotton fabrics has been improved to a certain extent, the strength loss rate has decreased, and the corresponding fabric style has also been improved.

[0143] Figure 5 The scanning electron microscope images of Example 1, Comparative Example 1 and Comparative Example 2 are 35 times, 900 times and 2000 times respectively. It can be seen from the figure that the surface of the fabric without enzyme treatment is relatively rough, and there are many messy short fibers, which are easy to rub and pill during subsequent wearing and use. However, the cotton fabric modified and finished by cellulase has fewer protruding fibrils on the surface of the fabric and improved surface finish because the surface short fibers are hydrolyzed. The improvement effect of the smooth surface of the fabric after DES combined with cellulase treatment is more obvious.

[0144] Figure 6The amount of hydrolyzate after modification and finishing of Example 1 (DES-enzyme system, 0.5h), Control Example 2 (enzyme treatment alone, 0.5h) and Example 2 (DES-enzyme system, 1h), Control Example 4 (enzyme treatment alone, 1h) is compared. As can be seen from the figure, with the passage of enzyme treatment time, the content of reducing sugar in the reaction solution increases, and the enzyme treatment reaction continues. The amount of reducing sugar produced by enzyme treatment alone within 30min is higher, but with the increase of reaction time, the difference between the two decreases, which may be due to the stabilizing effect of DES on cellulase. Due to the synergistic effect of DES and enzyme, the surface fiber short fibers can be hydrolyzed more effectively, reducing excessive hydrolysis during the modification and finishing process, the amount of hydrolyzate is reduced, and the internal structure of the fabric is effectively protected, reducing strength loss.

[0145] Example 12

[0146] The difference from Example 1 is that AA-SA is replaced with citric acid-sodium citrate buffer.

[0147] The strength loss rate and softening effect of the cotton fabric obtained in Example 12 are similar to those of the acetic acid-sodium acetate buffer. It can be seen that the type of buffer has little interference with the system, and only the corresponding pH environment needs to be provided. This solution is suitable for various buffer systems.

[0148] The embodiments provided above are not intended to limit the scope of the present invention, and the steps described are not intended to limit the execution order thereof. Those skilled in the art may make obvious improvements to the present invention in combination with existing common knowledge, which also fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for low-strength modification and finishing of cotton fabrics using DES combined with cellulase, characterized in that: The steps include: (1) Preparation of DES / buffer solution The buffer solution is mixed with a DES solvent, and subjected to ultrasonic treatment to prepare a DES / buffer solution; the DES solvent is one of a neutral DES solvent, an acidic DES solvent, and an alkaline DES solvent; (2) Enzyme treatment The cotton fabric is immersed in a DES / buffer solution, a cellulase preparation is added, and bioenzyme finishing is performed to obtain the finished cotton fabric; (3) High temperature inactivation The finished cotton fabric is inactivated in a water bath at high temperature, washed and dried to obtain the modified cotton fabric.

2. The method according to claim 1, characterized in that In step (1), the preparation method of the DES solvent is to mix the hydrogen bond donor and the hydrogen bond acceptor, and heat and stir until the mixture becomes clear and transparent to obtain the DES solvent; The hydrogen bond acceptor is one of choline chloride and betaine; The hydrogen bond donor of the neutral DES solvent is one of glycerol, polyethylene glycol 200, and polyethylene glycol 600; The hydrogen bond donor of the acidic DES solvent is one of acetic acid, formic acid, and p-toluenesulfonic acid; The hydrogen bond donor of the alkaline DES solvent is one of urea, ethylene glycol, and 1,3-propylene glycol; The molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:2 or 1:

5.

3. The method according to claim 2, characterized in that In the preparation method of DES solvent, the heating and stirring temperature is 80-100° C.; the heating and stirring time is 2-6 hours.

4. The method according to claim 1, characterized in that: In step (1), the pH of the buffer solution is 4.3-6.3; the DES solvent concentration of the DES / buffer solution is 5-30wt%; and the buffer solution is selected from one of acetic acid-sodium acetate buffer and citric acid-sodium citrate buffer.

5. The method according to claim 1, characterized in that In step (2), the bath ratio of cotton fabric to DES / buffer solution is 1:8 to 1:

14.

6. The method according to claim 1, characterized in that In step (2), the enzyme activity of the cellulase preparation is 500-1000 EGU / g, and the amount of the cellulase preparation used is 2-4% owf of the cotton fabric.

7. The method according to claim 1, characterized in that In step (2), the enzyme finishing is carried out at 45 to 55° C. for 30 to 60 minutes.

8. The method according to claim 1, characterized in that In step (3), the temperature of the water bath high temperature inactivation is 90 to 100° C., and the treatment time of the water bath high temperature inactivation is 8 to 20 minutes.

9. The modified cotton fabric prepared by the method according to any one of claims 1 to 8.

10. Use of the modified cotton fabric according to claim 9 in the field of textiles.

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