An impregnation aid for viscose fiber production

Abstract

This invention belongs to the field of viscose fiber technology, specifically relating to a bleaching aid for viscose fiber production. The bleaching aid is naphthol polyoxyethylene ether, with the chemical formula: HO(CH2CH2O). x -Naphthyl-(OCH2CH2) y In the formula OH, Naphthyl represents a naphthalene ring, and x and y represent the number of ethylene oxide units, where x and y are integers. This invention discloses a novel impregnation aid for viscose fiber production. Experiments have shown that the impregnation aid of this invention has good solubility, good wetting properties, low foaming power, and excellent reactivity. This impregnation aid can significantly improve the reactivity between alkali cellulose and CS2 and accelerate xanthation, outperforming conventional phenylethoxylated impregnation aids. This invention also provides a method for preparing this impregnation aid, which has the advantages of simple reaction, convenient preparation, and low cost, making it suitable for large-scale industrial production.

Description

Technical Field

[0001] This invention belongs to the field of viscose fiber technology, and specifically relates to an impregnation aid for viscose fiber production. Background Technology

[0002] Viscose fiber is an important type of semi-synthetic fiber and is usually produced by the viscose process. The chemical reaction in the viscose process is based on the reaction of alkali cellulose with proton-loving CS2 to produce xanthate esters. Cellulose xanthate esters are dissolved in dilute caustic soda to obtain a viscose solution. The viscose solution is extruded through fine spinnerets into an acid bath to regenerate cellulose into filaments, which are the so-called viscose fibers.

[0003] Surfactants play a crucial role in the production of viscose fibers. The presence of surfactants in the mercerizing process accelerates the wetting of cellulose with the alkaline solution, increases the swelling degree of the cellulose material, results in a low-foaming alkaline solution, promotes the removal of hemicellulose, and enhances the reactivity of the cellulose material in mercerizing and subsequent xanthation. The presence of surfactants in alkali cellulose, particularly during the pulverization process, not only affects the properties of the resulting product but also influences the pulverization itself by promoting the mechanical breakdown of alkali cellulose. This manifests as a reduction in the energy required for pulverization and a decrease in the duration of the pulverization cycle.

[0004] Nonionic and cationic surfactants are typically chosen as impregnation aids. Polyethylene glycol was initially used industrially as an impregnation aid, but it has several drawbacks, such as poor wetting ability of alkaline solutions on cellulose and low reactivity in improving subsequent xanthation. Currently, phenylethoxylated compounds are widely used as impregnation aids in the viscose fiber industry. However, these surfactants have low solubility in the alkaline environment of mercerizing cellulose pulp, resulting in poor wetting of the cellulose pulp by the alkaline solution, and also low reactivity of alkali cellulose with carbon disulfide during xanthation. Therefore, there is an urgent need to develop new impregnation aids to improve the efficiency of the processing and optimize viscose fiber production. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an impregnation aid for viscose fiber production.

[0006] The objective of this invention is achieved through the following technical solution: a bleaching aid for viscose fiber production, wherein the bleaching aid is naphthol polyoxyethylene ether, with the chemical formula: HO(CH2CH2O). x -Naphthyl-(OCH2CH2) y OH, where Naphthyl represents a naphthalene ring, and x and y represent the number of oxyethylene units, where x and y are both integers.

[0007] As a preferred technical solution, the naphthol polyoxyethylene ether includes at least one of 1,2-naphthol polyoxyethylene ether, 1,3-naphthol polyoxyethylene ether, 1,4-naphthol polyoxyethylene ether, 1,5-naphthol polyoxyethylene ether, 1,6-naphthol polyoxyethylene ether, 1,7-naphthol polyoxyethylene ether, 1,8-naphthol polyoxyethylene ether, 2,3-naphthol polyoxyethylene ether, 2,6-naphthol polyoxyethylene ether, or 2,7-naphthol polyoxyethylene ether;

[0008]

[0009] Where x and y represent the number of ethylene oxide units, and both x and y are integers.

[0010] As a preferred technical solution, the naphthol polyoxyethylene ether is 1,5-naphthol polyoxyethylene ether, and x = y.

[0011] Preferably, x is 5 to 10, and more preferably x is 8.

[0012] A method for preparing an impregnation aid for viscose fiber production, wherein naphthalene hydrochloride reacts with ethylene oxide under anaerobic heating conditions with a catalyst to generate naphthalene hydrochloride polyoxyethylene ether, wherein the catalyst is an alkaline compound of potassium or sodium, and the heating temperature is 140–169°C.

[0013] The preparation method of 1,5-naphthol polyoxyethylene ether is as follows: 1,5-naphthol and a catalyst are added to a reaction vessel, and ethylene oxide is added to the reaction vessel under vacuum and nitrogen atmosphere to carry out the reaction. The reaction temperature is 140-169℃, the pressure is 0.8-1.2 MPa, and the reaction time is 1-2 h. After the reaction is completed, 1,5-naphthol polyoxyethylene ether is obtained. The amount of catalyst added is 3‰-1% of the weight of 1,5-naphthol, and the molar ratio of 1,5-naphthol to ethylene oxide is 1:(x+y).

[0014] The synthetic route for 1,5-naphthol polyoxyethylene ether is as follows:

[0015]

[0016] For the present invention, the immersion aid of the present invention needs to be added before or during xanthan acidification, preferably before xanthan acidification, and more preferably before or during mercerizing.

[0017] The amount of the impregnation aid added in this invention is 0.01% to 3% based on the dry weight of the pulp, preferably 0.1% to 0.3%.

[0018] This invention has the following advantages: It discloses a novel impregnation aid for viscose fiber production. Experiments have shown that this aid exhibits good solubility, excellent wetting properties, low foaming power, and superior reactivity. This aid significantly improves the reactivity between alkali cellulose and CS2 and accelerates xanthation, demonstrating superior performance compared to conventional phenylethoxylated impregnation aids. Furthermore, this invention provides a method for preparing this impregnation aid, which is simple to prepare, convenient, and low in cost, making it suitable for large-scale industrial production. Attached Figure Description

[0019] Figure 1 The 1H NMR spectrum of the 1,5-naphthol polyoxyethylene ether synthesized in the experimental example of this invention.

[0020] Figure 2 The infrared spectrum of the 1,5-naphthol polyoxyethylene ether synthesized in the experimental example of this invention is shown. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments. The scope of protection of the present invention is not limited to the following: Embodiment 1: A method for preparing 1,5-naphthol polyoxyethylene ether as an impregnating agent for viscose fiber production.

[0022] 1,5-Naphthyldiol and a catalyst, potassium hydroxide, were added to a reaction vessel. Ethylene oxide was then added to the reaction vessel under vacuum and nitrogen atmosphere to carry out the reaction. The reaction temperature was 140℃, the pressure was 0.8 MPa, and the reaction time was 2 h. After the reaction was completed, 1,5-naphthyldiol polyoxyethylene ether was obtained, with the chemical formula: HO(CH2CH2O). x -Naphthyl-(OCH2CH2) y OH, where Naphthyl represents a naphthalene ring, x is 5, y is 5, the amount of catalyst added is 3‰ of the weight of 1,5-naphthyl, and the molar ratio of 1,5-naphthyl to ethylene oxide is 1:10.

[0023] Example 2: A method for preparing 1,5-naphthol polyoxyethylene ether, an impregnation aid for viscose fiber production.

[0024] 1,5-Naphthyldiol and a catalyst, sodium hydroxide, were added to a reaction vessel. Ethylene oxide was then added to the reaction vessel under vacuum and nitrogen atmosphere to carry out the reaction. The reaction temperature was 169°C, the pressure was 1.2 MPa, and the reaction time was 1 h. After the reaction was completed, 1,5-naphthyldiol polyoxyethylene ether was obtained, with the chemical formula: HO(CH2CH2O). x -Naphthyl-(OCH2CH2) yOH, wherein Naphthyl represents a naphthalene ring, x is 10, y is 10, the amount of catalyst added is 1% of the weight of 1,5-naphthyl, and the molar ratio of 1,5-naphthyl to ethylene oxide is 1:20.

[0025] Example 3: A method for preparing 1,5-naphthol polyoxyethylene ether, an impregnation aid for viscose fiber production.

[0026] 1,5-Naphthyldiol and a catalyst, potassium carbonate, were added to a reaction vessel. Ethylene oxide was then added to the reaction vessel under vacuum and nitrogen atmosphere to carry out the reaction. The reaction temperature was 158°C, the pressure was 1.0 MPa, and the reaction time was 1.5 h. After the reaction was completed, 1,5-naphthyldiol polyoxyethylene ether was obtained, with the chemical formula: HO(CH2CH2O). x -Naphthyl-(OCH2CH2) y OH, where Naphthyl represents a naphthalene ring, x is 8, y is 8, the amount of catalyst added is 5‰ of the weight of 1,5-naphthyl, and the molar ratio of 1,5-naphthyl to ethylene oxide is 1:16.

[0027] The following experiments illustrate the beneficial effects of this invention:

[0028] Experimental example:

[0029] In a reaction vessel equipped with a mechanical stirrer, thermometer, and pressure gauge, 160.17 g of 1,5-naphthyldiol and 1.6017 g of potassium hydroxide were added. After the vacuum pump was started to purge the air from the vessel, the mixture was purged with nitrogen 3-5 times. Then, at a temperature of 150℃ and a pressure of 0.1 MPa, 704.83 g of ethylene oxide was added, and the reaction was allowed to proceed for 1.5 hours. The final product was 1,5-naphthyldiol polyoxyethylene ether with the chemical formula HO(CH2CH2O). x -Naphthyl-(OCH2CH2) y OH, where Naphthyl represents the naphthalene ring, x is 8, and y is 8. The synthesized 1,5-naphthol polyoxyethylene ether was analyzed using infrared spectroscopy and nuclear magnetic resonance spectroscopy, and the results are as follows: Figure 1 and Figure 2 As shown, this invention successfully synthesizes 1,5-naphthol polyoxyethylene ether.

[0030] The 1,5-naphthol polyoxyethylene ether (abbreviated as 1,5-DHN) synthesized in the experimental example was subjected to the following experimental tests:

[0031] 1. Solubility test

[0032] Add 0.3 g of surfactant to 100 g of 10% NaOH solution, stir well, let stand for 1 h, and observe the appearance. The results are shown in Table 1 below:

[0033] Table 1: Solubility Test Results

[0034] surfactants Appearance 1,5-DHN clear and transparent Phenylacetyl compounds A small amount of insoluble matter

[0035] 2. Wetting power test

[0036] The test was conducted at room temperature according to the method specified in the national standard GB / T 11983-2008 "Test of Wetting Power of Surfactants - Immersion Method". A shorter wetting time indicates better wetting performance, and the results are shown in Table 2.

[0037] Table 2: Results of Wetting Force Test

[0038] surfactants Wetting time 1,5-DHN 237 seconds Phenylacetyl compounds 386 seconds

[0039] 3. Foaming power test

[0040] The test was conducted at 50℃ according to the method of the national standard GB / T 7462-94 "Determination of Foaming Power of Surfactants - Modified Ross-Miles Method" with a surfactant solution concentration of 10 g / L. The results are shown in Table 3.

[0041] Table 3: Results of Foaming Power Test

[0042]

[0043]

[0044] As shown in Table 3, 1,5-DHN has a much lower foaming power than phenylethoxy compounds.

[0045] 4. Reaction performance test

[0046] Cellulose pulp was reacted sequentially with certain amounts of sodium hydroxide and carbon disulfide to form cellulose xanthate. The time difference between the passage of equal volumes of cellulose xanthate solution through filter pores was measured; a shorter time difference indicated better reaction performance. The results are shown in Table 4.

[0047] Table 4: Results of Reaction Performance Tests

[0048] surfactants Time difference 1,5-DHN 78s Phenylacetyl compounds 180s

[0049] As shown in Table 4, 1,5-DHN has better reactivity than phenylethoxy compounds.

[0050] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, are covered within the scope of protection of the present invention.

Claims

1. A blistering agent for viscose fiber production, characterized in that, The impregnation aid is 1,5-naphthol polyoxyethylene ether, with the chemical formula: HO(CH2CH2O). x -Naphthyl-(OCH2CH2) y OH, where Naphthyl represents a naphthalene ring, where x is 8 and y is 8, is added before or during xanthate acidification. The amount of the leaching aid added is 0.01% to 3% based on the dry weight of the pulp. 。

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