CN111394817A - Novel preparation process of regenerated cellulose fiber - Google Patents
Novel preparation process of regenerated cellulose fiber Download PDFInfo
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- CN111394817A CN111394817A CN202010296921.2A CN202010296921A CN111394817A CN 111394817 A CN111394817 A CN 111394817A CN 202010296921 A CN202010296921 A CN 202010296921A CN 111394817 A CN111394817 A CN 111394817A
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- cellulose
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- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F2/00—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof
- D01F2/02—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from solutions of cellulose in acids, bases or salts
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- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01D—MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- D01D1/00—Treatment of filament-forming or like material
- D01D1/02—Preparation of spinning solutions
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- Textile Engineering (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Artificial Filaments (AREA)
Abstract
The invention discloses a novel preparation process of regenerated cellulose fibers, wherein a solvent for dissolving raw material cellulose pulp in the preparation process of a cellulose fiber spinning solution is a mixed solvent of a TBAH organic alkali solvent and a DMSO (dimethyl sulfoxide) dissolving aid, wherein the DMSO dissolving aid accounts for 10-90% of the total mass of the mixed solvent, the purity of the DMSO dissolving aid is more than 90wt%, and the TBAH organic alkali solvent is a TBAH aqueous solution with the concentration of more than 40 wt%. The solvent in the spinning solution preparation process is a mixed solvent of a DMSO (dimethyl sulfoxide) dissolving auxiliary agent and a TBAH organic alkali solvent, the preparation of the high-efficiency and high-quality regenerated cellulose fiber can be realized by matching a coagulating bath, and compared with the prior art, the preparation method has the remarkable advantages of low cost, high spinning speed, high quality, environmental friendliness and the like, so that the preparation process of the regenerated cellulose fiber provided by the invention has extremely high industrial value.
Description
Technical Field
The invention belongs to the technical field of regenerated cellulose fiber spinning processes, and particularly relates to a novel preparation process of regenerated cellulose fibers.
Background
The traditional production process for preparing regenerated cellulose fibers by a viscose method has the defects of long process, high energy consumption, serious environmental pollution, high cost and the like, seriously restricts the development of the regenerated cellulose fibers in terms of production, and solves the problems of research and development of renewable alternative resources, environmental protection and the like in order to solve the problem of exhaustion of resources such as petroleum and the like. At present, a process of directly dissolving an alpha cellulose raw material in a mixed solvent of dimethyl sulfoxide (DMSO) and tetrabutylammonium hydroxide (TBAH) and then treating the mixed solvent has been developed, but the mixing ratio of the DMSO and TBAH mixed solvent has an influence on the composition of a coagulation bath, the temperature and the spinning speed, and the solubility of alpha cellulose, but the ratio and a specific regenerated cellulose fiber spinning method are rarely studied at present.
Disclosure of Invention
The invention solves the technical problems that a novel preparation process of regenerated cellulose fiber with simple process and low cost is provided, and the main technical problem solved by the preparation process is that the dissolving effect of cellulose is greatly improved, the dissolving efficiency is improved, and the stability and the spinnability of cellulose solution are improved by improving the mixing ratio of DMSO and TBAH solvents; meanwhile, the viscosity of the cellulose solution can be effectively reduced, the long-distance transportation of the cellulose solution at normal temperature is facilitated, and the transmission energy consumption and the cost are reduced; with the addition of the DMSO dissolution aid, the alkali content of the cellulose solution is relatively reduced, the proportion of acid in the coagulation bath can be further optimized, the use amount of the acid is greatly reduced, the chemical pollution is reduced, and meanwhile, the working environment of operators is improved.
The invention adopts the following technical scheme for solving the technical problems, and the novel preparation process of the regenerated cellulose fiber is characterized by comprising the following steps of: the solvent for dissolving the raw material cellulose pulp in the preparation process of the cellulose fiber spinning solution is a mixed solvent of a TBAH organic alkali solvent and a DMSO dissolving aid, wherein the DMSO dissolving aid accounts for 0-90% of the total mass of the mixed solvent, the purity of the DMSO dissolving aid is more than 90wt%, the DMSO dissolving aid is used for fully infiltrating an amorphous region and a sub-crystalline region in a cellulose structure, the competitive relationship between the DMSO dissolving aid and the TBAH organic alkali solvent is avoided to the utmost extent, the diffusion of the solvent to the inside of cellulose is promoted, the balance regulation between the solvent diffusion and the cellulose dissolution is realized, the cellulose is dissolved more efficiently, the DMSO dissolving aid is used for improving the stability of the obtained cellulose solution, the DMSO dissolving aid can be stably adsorbed on the surface of the dissolved cellulose molecules, the regeneration and agglomeration of the dissolved cellulose are effectively inhibited, and the viscosity of the cellulose solution can be effectively reduced by the DMSO dissolving aid, the long-distance transportation of the cellulose solution at normal temperature is facilitated, and the TBAH organic alkali solvent is TBAH aqueous solution with the concentration of more than 40 wt%.
Further limited, the source of the raw material alpha cellulose pulp is wood, cotton linter, wheat straw, rice straw, reed, hemp, mulberry bark, paper mulberry bark or bagasse.
Further defined, the dissolving of the feedstock cellulose pulp comprises: mixing a DMSO dissolving auxiliary agent and a TBAH organic alkali solvent, and then adding a raw material cellulose pulp for dissolving; or soaking the raw material cellulose pulp by using a DMSO (dimethyl sulfoxide) dissolving auxiliary agent, and then adding a TBAH organic alkali solvent for dissolving; or firstly soaking the raw material cellulose pulp by using the DMSO dissolving auxiliary agent, and then adding the mixed solution of the residual DMSO dissolving auxiliary agent and the TBAH organic alkali solvent for dissolving.
Further defined, the novel processes for preparing the regenerated cellulose fibers include, but are not limited to, continuous spinning processes of regenerated cellulose fibers, centrifugal spinning, spun staple spinning, cellophane, and dry jet wet spinning of regenerated cellulose fibers.
The novel preparation process of the regenerated cellulose fiber is characterized by comprising the following process flows of mixing alpha cellulose pulp and TBAH organic alkali solvent with DMSO dissolution auxiliary agent → dissolution → filtration → deaeration → screw pump delivery → metering pump → front filter of a spinneret → extrusion molding → drafting → water washing → oiling → drying → winding → finished fiber, wherein the DMSO dissolution auxiliary agent accounts for 80% of the total mass of the mixed solvent, the purity of the DMSO dissolution auxiliary agent is 95wt%, the content of the alpha cellulose pulp in spinning solution is 10wt%, the TBAH organic alkali solvent is TBAH aqueous solution with the concentration of 50wt%, and coagulation bath parameters comprise that the concentration of sulfuric acid is 150 g/L, the temperature is 40 ℃, and high-quality finished regenerated cellulose fiber is prepared at the constant spinning speed of 140 m/min.
The solvent selected in the process of preparing the spinning solution is a mixed solvent of a TBAH organic alkali solvent and a DMSO dissolving aid. Here, the DMSO dissolution aid functions not only to dissolve a conventional solvent for preparing a spinning dope from cellulose but also to simply combine a TBAH organic base solvent with a DMSO dissolution aid, wherein the DMSO dissolution aid functions mainly in the following three aspects:
1) the DMSO dissolution aid can increase the accessibility of the cellulose, thereby allowing the solvent to penetrate into the interior of the cellulose and, in turn, dissolve the cellulose. One of the key problems involved in the dissolution process of cellulose is the swelling of the aggregated polymer, i.e. the diffusion of the solvent into the cellulose crystals. The dissolving process of cellulose in TBAH organic alkali solvent is a process of dissolving and diffusing simultaneously; the dissolution of cellulose causes a significant increase in the viscosity of the solution in the dissolution region, which is not favorable for the solvent to further diffuse into the cellulose, and thus the dissolution efficiency of the solvent system is low. The viscosity of a cellulose solution is very dependent on the degree of polymerization of cellulose. By introducing the dissolving auxiliary agent, the invention can fully infiltrate the amorphous region and the sub-crystalline region in the cellulose structure, promote the solvent to diffuse into the cellulose, realize the balance regulation between the solvent diffusion and the cellulose dissolution, and further more efficiently dissolve the cellulose. In this process, in addition to the competitive action between the dissolution aid and the cellulose and the competitive action between the organic alkali solvent and the cellulose, there is a competitive relationship between the dissolution aid and the organic alkali solvent. Among these, the latter is disadvantageous for the dissolution of cellulose and therefore needs to be avoided as much as possible. This means that not all dissolution aids commonly used in the art play a positive role in dissolution; if the intermolecular force between the dissolution auxiliary agent and the organic alkali solvent is too strong, the cellulose solubility of the organic alkali solvent is negatively affected.
2) The DMSO dissolution aid can improve the stability of the obtained cellulose solution. Since the organic base solvent is a non-derivatized cellulose solution, the cellulose is in an unstable state in solution, i.e., there is a possibility that the dissolved cellulose molecules are regenerated in a solution environment to form aggregates. The problem of poor stability of the cellulose solution exists in the dissolution of cellulose by a single organic alkali solvent. With the addition of the dissolving assistant, the dissolving assistant can be stably adsorbed on the surface of the dissolved cellulose molecules, so that the regeneration agglomeration of the dissolved cellulose is effectively inhibited. Too strong intermolecular interaction between the dissolution aid and the organic base solvent also needs to be avoided in order not to affect the solubility of the organic base to the cellulose. The invention comprehensively considers the competitive relationship among the organic alkali solvent, the dissolving assistant and the cellulose, and finally selects the organic alkali solvent and the dissolving assistant with ideal effect as the mixed solvent for dissolving the cellulose with high polymerization degree (more than 400 polymerization degree).
3) The DMSO dissolution auxiliary agent can effectively reduce the viscosity of the cellulose solution, is beneficial to realizing long-distance transportation of the cellulose solution at normal temperature, and reduces transmission energy consumption and cost. Meanwhile, with the addition of the DMSO dissolving assistant, the alkali content of the cellulose solution is relatively reduced, the proportion of acid in the coagulating bath can be further optimized, the use amount of the acid is greatly reduced, the pollution is reduced, the working environment of operators is improved, and the realization of energy-saving green safe industrial production is facilitated.
In addition, natural cellulose presents a complex multilayer structure. Cellulose raw materials from different sources have significant differences in aggregation structure, degree of polymerization and the like, and also have significant differences in trace element content, non-cellulose components (hemicellulose, lignin and the like), combination modes thereof and the like. Thus, there is a clear difference in the ease of dissolution of cellulosic raw materials of different origin from a technical point of view. For cellulose raw materials having a high polymerization degree (such as cotton pulp, wood pulp, etc.), the organic alkali solvent does not dissolve these celluloses well. Due to the key synergistic effect of the dissolution auxiliary agent, the dissolving capacity of the mixed solvent to the cellulose is remarkably improved, which is particularly shown in that the mixed solvent can well dissolve the cellulose raw material with higher polymerization degree.
The solvent in the spinning solution preparation process is a mixed solvent of a DMSO (dimethyl sulfoxide) dissolving auxiliary agent and a TBAH organic alkali solvent, the preparation of the high-efficiency and high-quality regenerated cellulose fiber can be realized by matching a coagulating bath, and compared with the prior art, the preparation method has the remarkable advantages of low cost, high spinning speed, high quality, environmental friendliness and the like, so that the preparation process of the regenerated cellulose fiber provided by the invention has extremely high industrial value.
Detailed Description
The present invention is described in further detail below with reference to examples, but it should not be construed that the scope of the above subject matter of the present invention is limited to the following examples, and that all the technologies realized based on the above subject matter of the present invention belong to the scope of the present invention.
The process flow of the invention is as follows: mixing alpha cellulose with a DMSO dissolution auxiliary agent and a TBAH organic alkali solvent → dissolving → filtering → defoaming → conveying by a screw pump → a metering pump → filtering before a spinning head → extrusion molding → drafting → washing with water → oiling → drying → winding → finished fiber.
Wherein the purity of the selected DMSO dissolving auxiliary agent is 95wt%, the TBAH organic alkali solvent is TBAH aqueous solution with the concentration of 50wt%, the cotton pulp is used as the raw material, spinning solution with the content of 10wt% alpha cellulose is prepared, and a comparison test is carried out at a constant spinning speed of 140 m/min.
In the embodiment, the proportion of the DMSO dissolution aid to the TBAH aqueous solution is improved, so that the spinning solution with lower viscosity can be obtained, the physical index of the fiber can be effectively improved, and the use amount of acid can be reduced. Wherein the DMSO dissolution auxiliary agent and the TBAH organic alkali solvent have the best effect when the mass ratio is 8/2.
While there have been shown and described what are at present considered the fundamental principles of the invention, its essential features and advantages, the invention further resides in various changes and modifications which fall within the scope of the invention as claimed.
Claims (4)
1. A novel preparation process of regenerated cellulose fiber is characterized by comprising the following steps: the solvent for dissolving the raw material cellulose pulp in the preparation process of the cellulose fiber spinning solution is a mixed solvent of a TBAH organic alkali solvent and a DMSO dissolving aid, wherein the DMSO dissolving aid accounts for 0-90% of the total mass of the mixed solvent, the purity of the DMSO dissolving aid is more than 90wt%, the DMSO dissolving aid is used for fully infiltrating an amorphous region and a sub-crystalline region in a cellulose structure, the competitive relationship between the DMSO dissolving aid and the TBAH organic alkali solvent is avoided to the utmost extent, the diffusion of the solvent to the inside of cellulose is promoted, the balance regulation between the solvent diffusion and the cellulose dissolution is realized, the cellulose is dissolved more efficiently, the DMSO dissolving aid is used for improving the stability of the obtained cellulose solution, the DMSO dissolving aid can be stably adsorbed on the surface of the dissolved cellulose molecules, the regeneration and agglomeration of the dissolved cellulose are effectively inhibited, and the DMSO dissolving aid can effectively reduce the viscosity of the cellulose solution, the long-distance transportation of the cellulose solution at normal temperature is facilitated, and the TBAH organic alkali solvent is TBAH aqueous solution with the concentration of more than 40 wt%.
2. A novel process for the preparation of regenerated cellulose fibers according to claim 1, characterized in that: the source of the raw material alpha cellulose pulp is wood, cotton linter, wheat straw, rice straw, reed, hemp, mulberry bark, paper mulberry bark or bagasse.
3. A novel process for the preparation of regenerated cellulose fibers according to claim 1, characterized in that: the novel preparation process of the regenerated cellulose fiber comprises but is not limited to a continuous spinning process, centrifugal spinning, short-filament spinning, cellophane and dry-jet wet spinning of the regenerated cellulose fiber.
4. The novel process for preparing regenerated cellulose fibers according to claim 1, characterized in that the process flow is mixing alpha cellulose pulp and TBAH organic alkali solvent with DMSO dissolution auxiliary agent → dissolution → filtration → deaeration → screw pump delivery → metering pump → filter ahead of spinneret → extrusion molding → drafting → water washing → oiling → drying → winding → finished fiber, wherein DMSO dissolution auxiliary agent accounts for 80% of the total mass of the mixed solvent, the purity of DMSO dissolution auxiliary agent is 95wt%, the content of alpha cellulose pulp in the spinning solution is 10wt%, TBAH organic alkali solvent is TBAH aqueous solution with concentration of 50wt%, coagulation bath parameters are sulfuric acid concentration 150 g/L, temperature is 40 ℃, and high quality finished regenerated cellulose fibers are prepared at constant spinning speed of 140 m/min.
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| CN202010296921.2A CN111394817A (en) | 2020-04-15 | 2020-04-15 | Novel preparation process of regenerated cellulose fiber |
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| CN202010296921.2A CN111394817A (en) | 2020-04-15 | 2020-04-15 | Novel preparation process of regenerated cellulose fiber |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112323164A (en) * | 2020-12-01 | 2021-02-05 | 许昌学院 | Protein modified regenerated cellulose fiber and production process thereof |
| CN112458565A (en) * | 2020-11-20 | 2021-03-09 | 中国科学院宁波材料技术与工程研究所 | Spinning solution based on derivatization system and preparation method and application thereof |
| CN115537954A (en) * | 2022-09-26 | 2022-12-30 | 新乡化纤股份有限公司 | Preparation method of cellulose spinning solution, product prepared by preparation method and application of product |
| CN116732620A (en) * | 2023-06-02 | 2023-09-12 | 新乡化纤股份有限公司 | Pulp impurity removing method based on novel solvent system spinning |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112458565A (en) * | 2020-11-20 | 2021-03-09 | 中国科学院宁波材料技术与工程研究所 | Spinning solution based on derivatization system and preparation method and application thereof |
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| CN116732620A (en) * | 2023-06-02 | 2023-09-12 | 新乡化纤股份有限公司 | Pulp impurity removing method based on novel solvent system spinning |
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