Application of a deep eutectic solvent in removing louse eggshells and preventing felting of wool

Abstract

The present invention discloses the application of a deep eutectic solvent in removing louse egg shells and preventing felting of wool. The deep eutectic solvent is prepared by mixing choline chloride and urea in a molar ratio of 1:2 and drying and heating at 80 °C until the liquid becomes homogeneous. Under short-term treatment conditions, this deep eutectic solvent can remove 80% of the louse egg shells on wool; at the same time, it can hydrolyze the scales on the surface of wool, improve the anti-felting effect, and the damage to the mechanical strength of wool is within an acceptable range, with the loss of the tensile mechanical strength of wool being less than 15%. In the wool felting treatment, under relatively short time and reasonable treatment conditions, the wool obtains excellent anti-felting shrinkage effect. Without a pretreatment process, the anti-felting effect of only treating with the deep eutectic solvent is comparable to the effect of wool modification in the prior art. The deep eutectic solvent plays an important role in developing an environmentally friendly technology for wool anti-felting shrinkage treatment and can replace the traditional highly polluting chlorination method in the textile industry.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical solvent materials, and particularly relates to application of a deep eutectic solvent in removing lice egg shells and preventing wool from being felted. Background Art

[0002] Sheep lice not only affect the health of sheep, but also lay eggs on the wool. After the eggs hatch, the louse egg shells are tightly attached to the wool and are difficult to remove. These residual egg shells seriously affect the value of the wool and cause many problems in subsequent processing, such as uneven dyeing and uneven bonding. Currently, various methods such as mechanical combing and chemical treatment have been used to remove louse egg shells, but there are still problems such as energy consumption, damage to wool and environmental pollution. Sheep louse egg shells are attached to the wool through a protein composed of multiple adhesive proteins; therefore, louse egg shells can be removed by protease treatment.

[0003] Wool is a keratin fiber with a layered structure and covered with scales. The felting effect caused by the friction of scales affects the dimensional stability and suitability of wool textiles for consumers. Since traditional chemical anti-felting methods can cause pollution, green anti-felting treatments have received attention in recent years. Deep eutectic solvents (DES) are a class of eco-friendly and inexpensive solvents that have shown their advancement as environmentally friendly sustainable solvents in the wool industry; however, deep eutectic solvents have not yet been applied to the removal of wool louse egg shells. Summary of the invention

[0004] In order to overcome the defects of the above-mentioned prior art, the present invention uses a deep eutectic flux, which can remove 80% of wool lice egg shells under short-term treatment conditions; at the same time, the deep eutectic flux can hydrolyze the scales on the surface of the wool, improve the anti-felting effect, and keep the damage to the mechanical strength of the wool within an acceptable range, thereby achieving the effect of removing wool scales and lice egg shells in one step.

[0005] To achieve the above-mentioned purpose, the present invention provides an application of a deep eutectic solvent in removing lice egg shells and preventing wool from felting, wherein the application is to incubate the deep eutectic solvent with wool and lice egg shells at 80-110° C. for 15-60 minutes.

[0006] The deep eutectic solvent is treated with wool and lice egg shells at 110° C. for 30 minutes to hydrolyze only the wool surface scales and the lice egg shell protein matrix adhering to the wool.

[0007] The deep eutectic solvent is prepared by mixing choline chloride and urea in a molar ratio of 1:2, drying and heating at 80°C, and when the liquid becomes uniform. The drying step is: choline chloride and urea are dried at 60°C for 4 hours respectively; the heating step is: the dried samples are mixed and heated for 4 hours to obtain DES.

[0008] Advantages of the present invention compared with the prior art:

[0009] A deep eutectic solvent (DES) prepared by the present invention can effectively remove 80% of the wool louse eggshells under short-term treatment conditions. At the same time, the deep eutectic solvent can hydrolyze the scales on the surface of the wool, improve the anti-felting effect, and the damage to the mechanical strength of the wool is within an acceptable range, and the loss of the tensile mechanical strength of the wool is less than 15%.

[0010] In the wool felting treatment, under relatively short time and reasonable treatment conditions, the wool obtained excellent anti-felting effect. In addition, without a pretreatment process, the anti-felting effect of only treating with the deep eutectic solvent is comparable to the effect of wool modification in the prior art. The deep eutectic solvent plays an important role in developing an environmentally friendly technology for wool anti-felting treatment. The deep eutectic solvent has made a breakthrough in removing louse eggshells and can replace the traditional highly polluting chlorination method in the textile industry to achieve the anti-felting effect on wool. Brief Description of the Drawings

[0011] Figure 1 SEM images of the morphology of the eggshell before and after treatment with the deep eutectic solvent prepared for the example (temperature is 110 °C);

[0012] Figure 2 Bar chart of the removal rate of louse eggshells treated with the deep eutectic solvent for the example;

[0013] Figure 3 SEM images of the microscopic structural morphology of the eggshell and wool treated with the deep eutectic solvent for the example. Detailed Embodiments

[0014] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited in any way. To avoid repetition, in the following embodiments, the raw materials are commercially available products without special instructions, and the methods used are conventional methods without special instructions.

[0015] The wool sample containing louse eggshells was pre-stained with Lanasol Red 2G for easy visualization. To quantitatively evaluate the performance of DES, wool samples containing about 10 eggshells were treated at 80 °C and 110 °C respectively, and the eggshell removal rate was determined by counting the remaining eggshells.

[0016] Approximately 50 mg of wool top was immersed in DES (mass-to-liquid ratio 1:20). A control group was also conducted. Each treatment group had 5 independent replicates. All treatments were carried out under the same conditions for 1 h, and samples were taken every 15 min. After cultivation, the wool samples were rinsed three times with deionized water and then dried in an oven at 60 °C for 2 h. The tensile mechanical properties of the dried wool top treated with DES were measured using an MTS-e43 type electronic universal testing machine (MTS Systems Corporation, China). Five replicates were measured for each sample group. The tensile strength of the wool fibers was determined according to the standard test method ASTM D1294-05(2013).

[0017] Wools treated with different treatments were rolled into felt balls. Different treatment times and treatment temperatures were set for each group. Then, the hand feeling of the wool felt balls was measured using an improved Aachen felt test. The felt ball diameters (horizontal rotation of the ball after the first measurement and vertical rotation of the ball after the second measurement) were recorded, and the obtained values were averaged to compensate for possible roundness deviations (IWTO-20-04, 2004). Then the felt ball density was calculated. An increase in the felt ball diameter indicates a decrease in the felt ball density and thus a reduction in the felting tendency (and vice versa). Three replicates were measured for each sample group.

[0018] Example 1

[0019] Preparation of deep eutectic solvent:

[0020] DES was prepared according to a one-step method. Choline chloride and urea were mixed in a molar ratio of 1:2 and dried and heated at 80 °C. When the liquid became homogeneous, DES was successfully prepared.

[0021] Example 2

[0022] Treatment effect of deep eutectic solvent on sheep louse eggs:

[0023] To test the efficiency of the deep eutectic solvent in removing louse egg shells from wool, it was incubated with wool and louse egg shells before dyeing at 80 °C and 110 °C for 15, 30, 45, 60 minutes, and wool samples containing 10 egg shells were used for each condition. The removal rate of the deep eutectic solvent treatment of louse egg shells is as Figure 2 shown. Treatment at 110 °C for 30 minutes is a suitable treatment condition, under which a removal rate of 80% can be achieved.

[0024] Example 3

[0025] Treatment effect of deep eutectic solvent on wool anti-felting:

[0026] Since the anti-felting treatment should maintain the mechanical strength of wool, an improved Aachen felting test method was used to evaluate the tensile strength of wool samples treated with deep eutectic solvents under tensile loads. The tensile strength and diameter data of wool treated with deep eutectic solvents at 80 °C and 110 °C for different treatment times are shown in Table 1.

[0027] Table 1 Tensile strength and diameter data of wool treated with deep eutectic solvents at 80 °C and 110 °C for different treatment times

[0028]

[0029] Average louse egg removal rate (n = 10), average felt ball diameter (n = 3) ± 1SD, average tensile strength (n = 3) ± 1SD. Superscript lowercase letters: significant differences between the control group and each enzyme treatment (P < 0.05).

[0030] The microstructural morphology of the eggshells and wool treated with deep eutectic solvents is as Figure 3 shown, where (A) SEM images of the protein matrix untreated (i), treated for 30 minutes (ii), and 60 minutes (iii); (B) surface and assembly structure of the eggshells (chitin) treated for 0 minutes (i), 30 minutes (ii), and 60 minutes (iii). (C) SEM images of wool fibers untreated (i), treated for 30 minutes (ii), and 60 minutes (iii). The scale bar in the figure is 20 μm.

[0031] Using the deep eutectic solvent DES prepared in the application examples, one-step simultaneous removal of wool scales and louse eggshells was achieved. The eggshell removal rate and anti-felting rate reached 80.0% and 22.7% respectively.

[0032] For any person skilled in the art, without departing from the scope of the technical solution of the present invention, many possible changes and modifications can be made to the technical solution of the present invention by using the technical content disclosed above, or modified into equivalent embodiments with equivalent changes. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. Application of a deep eutectic solvent in removing louse eggshells and preventing wool felting, characterized in that, the application is to incubate the deep eutectic solvent with wool and louse eggshells at a temperature of 80°C to 110°C for 15 to 60 minutes; simultaneously remove wool scales and louse eggshells in one step, and the eggshell removal rate and anti-felting rate reach 80.0% and 22.7% respectively; the deep eutectic solvent is composed of choline chloride and urea in a molar ratio of 1:

2. Choline chloride and urea are dried at 60°C for 4 hours respectively; the dried samples are mixed and heated at 80°C for 4 hours, and the deep eutectic solvent DES is prepared when the liquid becomes uniform.

2. The application of the deep eutectic solvent according to claim 1 in removing louse eggshells and preventing wool felting, characterized in that, the deep eutectic solvent is treated with wool and louse eggshells at 110°C for 30 minutes.

3. The application of the deep eutectic solvent according to claim 2 in removing louse eggshells and preventing wool felting, characterized in that, the loss of the tensile mechanical strength of the wool in the application is less than 15%.

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