Immersion aid for viscose fiber production

Abstract

The invention belongs to the technical field of viscose fibers, and particularly relates to a leaching aid for viscose fiber production. The leaching aid is naphthalene diphenol polyoxyethylene ether, the chemical formula of the leaching aid is HO (CH2CH2O) x-Napthyl-(OCH2CH2) yOH, in the formula, Napthyl represents a naphthalene ring, x and y represent the number of oxyethylene units, and both x and y are integers. The invention discloses a novel auxiliary leaching agent for viscose fiber production, experiments find that the auxiliary leaching agent has good solubility, good wettability, low foaming power and excellent reaction performance, and the auxiliary leaching agent can significantly improve the reactivity between alkali cellulose and CS2 and accelerate xanthation; the use effect of the leaching aid is superior to that of a conventional phenyl ethyoxyl compound leaching aid. The invention further provides a preparation method of the leaching aid, and the preparation method has the advantages of simple reaction, convenience in preparation and low cost, and is suitable for industrial large-scale production.

Description

Technical Field

[0001] The invention belongs to the technical field of viscose fibers, and in particular relates to a soaking aid for viscose fiber production. Background Art

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

[0003] Surfactants play a very important role in the production of viscose fibers. The presence of surfactants in the mercerization step accelerates the wetting of cellulose by the alkaline solution, increases the swelling of the cellulosic material, makes the alkaline solution low-foaming, promotes the removal of hemicellulose and increases the reactivity of the cellulosic material in the mercerization and subsequent xanthation. The presence of surfactants in alkali cellulose, especially in the comminution process, not only affects the properties of the obtained product, but also affects the comminution itself by promoting the mechanical destruction of the alkali cellulose, which is manifested by a reduction in the energy required for comminution and a reduction in the duration of this cycle.

[0004] Nonionic and cationic surfactants are usually selected as soaking aids. Polyethylene glycol was first used as a soaking aid in industry, but it has some problems, such as poor ability to wet cellulose with alkaline solution and low reactivity to improve subsequent xanthation. Currently in the viscose fiber industry, phenylethoxy compounds are widely used as soaking aids. However, this surfactant has low solubility in the alkaline environment of the mercerization treatment of cellulose pulp, resulting in poor wettability of cellulose pulp with alkaline solution, and low reactivity of alkaline cellulose with carbon disulfide during xanthation. Therefore, it is urgent to develop new soaking aids to improve the efficiency of the treatment process and optimize viscose fiber production. Summary of the invention

[0005] The purpose of the present invention is to overcome the disadvantages of the prior art and provide a soaking aid for viscose fiber production.

[0006] The purpose of the present invention is achieved by the following technical scheme: A soaking agent for viscose fiber production, the soaking agent is naphthalene diphenol polyoxyethylene ether, the chemical formula is: HO(CH2CH2O) x -Naphthyl-(OCH2CH2) y OH, wherein Naphthyl represents a naphthalene ring, x and y represent the number of ethylene oxide units, and x and y are both integers.

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

[0008]

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

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

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

[0012] A method for preparing a soaking aid for viscose fiber production, wherein naphthalene diphenol reacts with ethylene oxide under the catalysis of a catalyst and in an oxygen-free heating environment to generate naphthalene diphenol 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-naphthalene diol polyoxyethylene ether is as follows: 1,5-naphthalene diol and a catalyst are added to a reaction kettle, ethylene oxide is added to the reaction kettle under vacuum and nitrogen atmosphere for reaction, the reaction temperature is 140-169°C, the pressure is 0.8-1.2 MPA, the reaction time is 1-2 hours, and the reaction is completed to obtain 1,5-naphthalene diol polyoxyethylene ether. The amount of the catalyst added is 3‰-1% of the weight of 1,5-naphthalene diol, and the molar ratio of 1,5-naphthalene diol to ethylene oxide is 1:(x+y).

[0014] The synthetic route of 1,5-naphthalene diol polyoxyethylene ether is:

[0015]

[0016] For the present invention, it is necessary to add the soaking aid of the present invention before or during xanthation, preferably before xanthation, more preferably before or during the mercerization stage;

[0017] The addition amount of the soaking aid of the present invention is 0.01% to 3%, preferably 0.1% to 0.3%, based on the dry weight of the pulp.

[0018] The invention has the following advantages: the invention discloses a new soaking aid for viscose fiber production, and experiments show that the soaking aid has good solubility, good wetting performance, low foaming power, and excellent reaction performance. The soaking aid can significantly improve the reactivity between alkali cellulose and CS2 and accelerate xanthation, which is better than the use effect of conventional phenylethoxy compound soaking aids. The invention also provides a preparation method of the soaking aid, which has the advantages of simple reaction, convenient preparation, and low cost, and is suitable for industrial large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of the 1,5-naphthalenediol polyoxyethylene ether synthesized in the experimental example of the present invention.

[0020] Figure 2 This is the infrared spectrum of the 1,5-naphthalenediol polyoxyethylene ether synthesized in the experimental example of the present invention. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and embodiments. The protection scope of the present invention is not limited to the following: Example 1: Preparation method of 1,5-naphthalene diphenol polyoxyethylene ether, a soaking agent for viscose fiber production

[0022] 1,5-naphthalene diol and a catalyst are added to the reactor, wherein the catalyst is potassium hydroxide, and ethylene oxide is added to the reactor under vacuum and nitrogen atmosphere for reaction. The reaction temperature is 140°C, the pressure is 0.8 MPA, and the reaction time is 2 hours. After the reaction is completed, 1,5-naphthalene diol polyoxyethylene ether is obtained, and the chemical formula is: HO(CH2CH2O) x -Naphthyl-(OCH2CH2) y OH, wherein Naphthyl represents a naphthalene ring, x is 5, y is 5, the amount of the catalyst added is 3‰ of the weight of 1,5-naphthalenediol, and the molar ratio of 1,5-naphthalenediol to ethylene oxide is 1:10.

[0023] Example 2: A method for preparing 1,5-naphthalene diphenol polyoxyethylene ether as a soaking agent for viscose fiber production

[0024] 1,5-naphthalene diol and a catalyst are added to the reactor, wherein the catalyst is sodium hydroxide, and ethylene oxide is added to the reactor under vacuum and nitrogen atmosphere for reaction. The reaction temperature is 169° C., the pressure is 1.2 MPA, and the reaction time is 1 h. After the reaction is completed, 1,5-naphthalene diol polyoxyethylene ether is obtained, and the chemical formula is: HO(CH2CH2O) x -Naphthyl-(OCH2CH2) yOH, wherein Naphthyl represents a naphthalene ring, x is 10, y is 10, the added amount of the catalyst is 1% by weight of 1,5-naphthalenediol, and the molar ratio of 1,5-naphthalenediol to ethylene oxide is 1:20.

[0025] Example 3: Preparation method of 1,5-naphthalene diphenol polyoxyethylene ether as a soaking agent for viscose fiber production

[0026] 1,5-naphthalene diol and a catalyst are added to the reactor, wherein the catalyst is potassium carbonate, and ethylene oxide is added to the reactor under vacuum and nitrogen atmosphere for reaction. The reaction temperature is 158°C, the pressure is 1.0 MPA, and the reaction time is 1.5 h. After the reaction is completed, 1,5-naphthalene diol polyoxyethylene ether is obtained, and the chemical formula is: HO(CH2CH2O) x -Naphthyl-(OCH2CH2) y OH, wherein Naphthyl represents a naphthalene ring, x is 8, y is 8, the amount of the catalyst added is 5‰ of the weight of 1,5-naphthalenediol, and the molar ratio of 1,5-naphthalenediol to ethylene oxide is 1:16.

[0027] The beneficial effects of the present invention are described below by experiments:

[0028] Experimental example:

[0029] In a reaction kettle equipped with mechanical stirring, thermometer and pressure gauge, add 160.17g of 1,5-naphthalenediol and 1.6017g of potassium hydroxide, start the vacuum pump to exhaust the air in the bottle, purge with nitrogen 3-5 times, then add 704.83g of ethylene oxide at a temperature of 150°C and a pressure of 0.1MPA, react for 1.5 hours, and finally obtain 1,5-naphthalenediol polyoxyethylene ether, the chemical formula is: HO(CH2CH2O) x -Naphthyl-(OCH2CH2) y OH, wherein Naphthyl represents a naphthalene ring, x is 8, and y is 8. The synthesized 1,5-naphthalene diol polyoxyethylene ether was analyzed by infrared spectrometer and nuclear magnetic resonance. The results are as follows: Figure 1 and Figure 2 As shown, it is shown that the present invention successfully synthesizes 1,5-naphthalene diol polyoxyethylene ether.

[0030] Take the 1,5-naphthalene diol polyoxyethylene ether (abbreviated as 1,5-DHN) synthesized in the experimental example for the following experimental tests:

[0031] 1. Solubility test

[0032] 0.3 g of surfactant was added to 100 g of 10% NaOH solution, stirred evenly, and the appearance was observed after standing for 1 hour. The results are shown in Table 1 below:

[0033] Table 1: Solubility test results

[0034] Surfactants Appearance 1,5-DHN Clear and transparent Phenyl ethoxylates A small amount of insoluble matter

[0035] 2. Wetting force test

[0036] According to the national standard GB / T 11983-2008 Immersion method for testing the wetting power of surfactants, the test was carried out at room temperature. A shorter wetting time means better wetting performance. The results are shown in Table 2:

[0037] Table 2: Wetting force test results

[0038] Surfactants Wetting time 1,5-DHN 237 seconds Phenyl ethoxylates 386 seconds

[0039] 3. Foaming power test

[0040] According to the national standard GB / T 7462-94 Determination of foaming power of surfactants - Improved Ross-Miles method, the test was conducted at 50°C, with a surfactant solution concentration of 10 g / L. The results are shown in Table 3:

[0041] Table 3: Foaming power test results

[0042]

[0043]

[0044] It can be seen from Table 3 that the foaming power of 1,5-DHN is much lower than that of phenylethoxy compounds.

[0045] 4. Reaction performance test

[0046] Cellulose pulp is chemically reacted with a certain amount of sodium hydroxide and carbon disulfide in sequence to form cellulose xanthate. The time difference between the same volume of cellulose xanthate solution passing through the filter holes is measured. A shorter time difference means better reaction performance. The results are shown in Table 4:

[0047] Table 4: Reaction performance test results

[0048] Surfactants Time Difference 1,5-DHN 78s Phenyl ethoxylates 180s

[0049] It can be seen from Table 4 that 1,5-DHN has better reaction performance than phenylethoxy compounds.

[0050] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which are all covered by the protection scope of the present invention.

Claims

1. A soaking aid for viscose fiber production, characterized in that: The soaking aid is naphthalene diphenol polyoxyethylene ether, and the chemical formula is: HO(CH2CH2O) x -Naphthyl-(OCH2CH2) y OH, wherein Naphthyl represents a naphthalene ring, x and y represent the number of ethylene oxide units, and x and y are both integers.

2. The impregnation aid for viscose fiber production according to claim 1, characterized in that: The naphthalene diphenol polyoxyethylene ether includes at least one of 1,2-naphthalene diphenol polyoxyethylene ether, 1,3-naphthalene diphenol polyoxyethylene ether, 1,4-naphthalene diphenol polyoxyethylene ether, 1,5-naphthalene diphenol polyoxyethylene ether, 1,6-naphthalene diphenol polyoxyethylene ether, 1,7-naphthalene diphenol polyoxyethylene ether, 1,8-naphthalene diphenol polyoxyethylene ether, 2,3-naphthalene diphenol polyoxyethylene ether, 2,6-naphthalene diphenol polyoxyethylene ether or 2,7-naphthalene diphenol polyoxyethylene ether; Wherein, x and y represent the number of ethylene oxide units, and both x and y are integers.

3. The impregnation aid for viscose fiber production according to claim 2, characterized in that: The naphthalene diol polyoxyethylene ether is 1,5-naphthalene diol polyoxyethylene ether, and x=y.

4. The impregnation aid for viscose fiber production according to claim 3, characterized in that: The x is 5-10.

5. The impregnation aid for viscose fiber production according to claim 4, characterized in that: The x is 8.

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