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WO2000012790A1 - Nouvelle fibre cellulosique regeneree et son procede de preparation - Google Patents

Nouvelle fibre cellulosique regeneree et son procede de preparation Download PDF

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Publication number
WO2000012790A1
WO2000012790A1 PCT/KR1999/000461 KR9900461W WO0012790A1 WO 2000012790 A1 WO2000012790 A1 WO 2000012790A1 KR 9900461 W KR9900461 W KR 9900461W WO 0012790 A1 WO0012790 A1 WO 0012790A1
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WO
WIPO (PCT)
Prior art keywords
cellulose
preparing
solution
naoh
spinning
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Ceased
Application number
PCT/KR1999/000461
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English (en)
Inventor
Dong Il Yoo
Sang Youn Oh
Keun Hoo Park
Young Se Oh
Won Ho Park
Chang Nam Choi
Kap Seung Yang
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Individual
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Individual
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Application filed by Individual filed Critical Individual
Priority to AU53079/99A priority Critical patent/AU5307999A/en
Publication of WO2000012790A1 publication Critical patent/WO2000012790A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
    • C08B16/00—Regeneration of cellulose
    • 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
    • D01F2/24—Monocomponent artificial filaments or the like of cellulose or cellulose derivatives; Manufacture thereof from cellulose derivatives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
    • C08B5/00—Preparation of cellulose esters of inorganic acids, e.g. phosphates
    • 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
    • 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
    • D01D5/00—Formation of filaments, threads, or the like
    • D01D5/06—Wet spinning methods

Definitions

  • the present invention relates to a process of preparing a regenerated cellulose fiber. More particularly, the present invention relates to a process of preparing a regenerated cellulose fiber, which comprises preparing a cellulose carbonate derivative, preparing a cellulose solution for spinning, and wet-spinning the cellulose solution. The present invention also includes the regenerated cellulose fiber prepared by the method of this invention.
  • Cellulose is one of the natural organic resources on earth, from which regenerated cellulose fiber has been obtained.
  • One is a direct solvent system method in which natural cellulose is directly dissolved in a solvent to prepare a cellulose solution and a spinning process of the cellulose solution is conducted.
  • the other is an indirect solvent system method in which a cellulose derivative is prepared from the natural cellulose, the cellulose derivative is dissolved in a solvent to prepare a cellulose solution and a spinning process of the cellulose solution is conducted.
  • a viscose rayon fiber is a representative example which is prepared by the indirect solvent system method.
  • the viscose rayon fiber is prepared by obtaining a cellulose xanthate derivative, which is soluble in an aqueous solution of NaOH, through reaction of aged cellulose with carbon disulfide, dissolving the cellulose xanthate derivative in an aqueous solution of 10 % by weight of NaOH, and spinning the solution into a spinning bath.
  • the natural cellulose has too high crystallinity and strong hydrogen bond to dissolve in a solvent and to regenerate as desired.
  • the representative examples of the direct solvent system method are an NMMO (N-methyl morpholine N-oxide) process, a NaOH/H 2 O process, a ZnCl- ⁇ /H2 ⁇ process, a cuprammonium process and the like.
  • NMMO N-methyl morpholine N-oxide
  • 10 % cellulose solution is obtained by dissolving cellulose in NMMO as solvent and 15.5 % water at temperature of 100 to 105 ° C .
  • the hydrogen bonds of cellulose molecular chains in the crystalline portion are broken, and new hydrogen bonds are formed between hydroxyl groups of the cellulose and amine oxide groups of NMMO.
  • the NMMO has a simple structure and can be recycled.
  • NMMO NMolethyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methyl methoxymethyl methacrylate.
  • NMMO is expensive and poor thermal stability.
  • the NMMO usually explodes over 150 °C .
  • As the NMMO tends to absorb moisture in the air to become a hydrate from an anhydride.
  • the degree of hydration of NMMO affects the melting point and solubility of cellulose. In spite of the above drawbacks, this process has been applied to mass production of a regenerated cellulose fiber and substituted for the viscous process.
  • the cellulose having lower degree of polymerization is prepared by treating pulp with steam explosion, then the cellulose is dissolved in a solvent of 9 ⁇ 13 % NaOH aqueous solution at 4 ° C over 8 hours to prepare a spinning solution.
  • the spinning solution contains 8 — 12 % by weight of cellulose as per water in the solution.
  • This process has disadvantages that it is difficult to dissolve cellulose in case of high degree of polymerization of cellulose, and that gelation occurs during spinning process in case of over 10 % by weight of cellulose.
  • the cellulose fiber prepared by this process has a strength of 0.85 — 1.5 g/den which is lower than that of the cellulose fibers prepared by other processes.
  • a spinning solution of cellulose is prepared by dissolving cellulose of 400 — 600 degree of polymerization in 40 % ZnCl 2 aqueous solution at 60 ° C for 15 — 60 minutes.
  • a halogen compound of Mg or Al is used as catalyst.
  • the spinning solution contains 5 ⁇ 45 % by weight of cellulose and 62 — 76 % by weight of ZnC .
  • the spinning solution is passed in the bath of water and ethanol to prepare regenerated cellulose fiber.
  • the cellulose fiber contains 0.4 % by weight of ZnCl 2 therein which will cause not to produce fine cellulose fiber.
  • the cuprammonium process use cuam (Cu(NH) 3 (OH)2) as solvent to dissolve cellulose.
  • cuam Cu(NH) 3 (OH)2
  • the copper is recovered so that the concentration of copper in the bath may be less than 0.1 ppm.
  • the physical properties of the cellulose fiber are good, but the cost for manufacture are higher than that of other processes.
  • the representative examples of the indirect solvent system method are a viscose process, a carbamat process, a LiCl/DMAc process and the like.
  • the viscose process is carried out by preparing a cellulose xanthate derivative through reaction of Na-cellulose with carbon disulfide, and dissolving the cellulose xanthate derivative in NaOH aqueous solution.
  • the spinning solution is passed in the bath containing sulfuric acid to produce a regenerated cellulose fiber.
  • the carbon disulfide used in this process are seriously harmful to human body.
  • a cellulose carbamate derivative is prepared by swelling the cellulose of about 400 degree of polymerization in ammonia aqueous solution and reacting the resulting solution with 10 % urea solution at 155 TJ .
  • the cellulose carbamate derivative can be easily hydrodegraded, but the cellulose having various degrees of polymerization cannot be dissolved.
  • the cellulose of about 400 degree of polymerization is swelled in LiCl or DMAc aqueous solution to preapre a cellulose derivative.
  • the cellulose derivative dissolves in the mixed solvent of LiCl DMAc.
  • the conventional processes for preparing a regenerated cellulose fiber have their own drawbacks, and it need to develop new processes or new solvents.
  • the present inventors have developed a new process which prepares a regenerated cellulose fiber by preparing a cellulose carbonate derivative, and then spinning the solution thereof.
  • An object of the present invention is to provide a process of preparing a regenerated cellulose fiber, which is not harmful to human body.
  • Another object of the present invention is to provide a process of preparing a regenerated cellulose fiber, which can dissolve a cellulose having a high degree of polymerization.
  • a further object of the present invention is to provide a process of preparing a regenerated cellulose fiber by preparing a cellulose carbonate derivative using carbon dioxide instead of preparing a cellulose xanthate derivative through reaction of Na-cellulose with carbon disulfide in the viscose process.
  • the process of preparing the regenerated cellulose fiber according to the present invention comprises providing Na-cellulose by treating natural cellulose with a NaOH aqueous solution, aging the Na-cellulose by exposing to air, removing an excess of NaOH from the aged cellulose by repeating washing and filtration, preparing a reacted cellulose by reacting the aged cellulose with carbon dioxide in a pretreating solution in a high pressure reactor, preparing a cellulose carbonate derivative from the reacted cellulose by repeating washing and filtration, preparing a spinning solution by dissolving the cellulose carbonate derivative in a mixed solvent of NaOH and ZnO aqueous solution, and wet- spinning the cellulose spinning solution in a bath.
  • pretreating solution examples are ZnCl 2 aqueous solution and mixed solution of ZnCl 2 and a lower alcohol.
  • the process of preparing a regenerated cellulose fiber in accordance with the present invention prepares a cellulose carbonate derivative using carbon dioxide instead of a cellulose xanthate derivative through reaction of Na-cellulose with carbon disulfide in the viscose process, therefore no harmful to human body. Also, this process may use all the equipments and apparatus of the conventional viscose process.
  • the present invention relates to a new process of preparing a regenerated cellulose fiber in which carbon disulfide is not used.
  • Natural cellulose is treated with a NaOH aqueous solution to prepare Na-cellulose.
  • natural cellulose cellulose pulp having molecular weight of about 100,000 and length and width of about 1 mm or cotton cellulose may be preferably used in this invention. Treating with a about 17.5 % NaOH aqueous solution at 0 — 5 TJ for 2 hours, the natural cellulose are swelled. During this treatment, soluble components such as hemicellulose are removed.
  • the reaction to prepare Na-cellulose from natural cellulose is shown as follow:
  • the Na-cellulose is exposed to air for aging.
  • the Na-cellulose is compressed and exposed to air at 50 TJ to prepare aged cellulose.
  • the molecular weight of cellulose depends on the time of aging.
  • the excess amount of NaOH is removed from the aged cellulose by repeating washing and filtration.
  • the washing and filtration are repeated about six times.
  • the aged cellulose that the excess amount of NaOH was removed is reacted with carbon dioxide in a pretreating solution in a high pressure reactor to prepare a reacted cellulose.
  • the examples of the pretreating solution are ZnCl 2 aqueous solution and mixed solution of ZnCl 2 and a lower alcohol.
  • the ZnCl 2 aqueous solution has preferably a concentration of 40 % ZnCl 2 .
  • the examples of the lower alcohol are methanol, ethanol, and propanol.
  • the weight ratio of ZnCl 2 and a lower alcohol is preferably 1 to 1.
  • the carbon dioxide is used in solid form of dry ice, liquid carbon dioxide or gaseous carbon dioxide. This reaction is preferably conducted for about two and a half hours.
  • the high pressure reactor is kept at 40 — 60 kgf/cm 2 .
  • a cellulose carbonate derivative is prepared from the reacted cellulose by repeating washing and filtration. The washing and filtration are usually repeated twice. During this step, the excess of ZnCl 2 and the lower alcohol is removed.
  • the reacted cellulose includes cellulose carbonate derivative as well as unreacted components, thus the cellulose carbonate derivative means a cellulose removing unreacted components from the reacted cellulose.
  • a cellulose spinning solution is prepared by dissolving the cellulose carbonate derivative in a mixed solvent of NaOH and ZnO aqueous solution. It is preferable to use about 10 % NaOH solution and a small amount of ZnO. It is preferable to use 3 % by weight of ZnO as per the NaOH aqueous solution.
  • the cellulose carbonate derivative is dissolved at -20 — 10 TJ for about 2 hours.
  • the concentration of the cellulose spinning solution depends on the molecular weight of cellulose derivative, but it is preferable to be in the range of about 5 to 10 %.
  • a regenerated cellulose fiber is obtained from the cellulose spinning solution through wet- spinning in a bath.
  • the bath is filled with a solution 10 % by weight of sulfuric acid, 20 % by weight of sodium sulphate and 70 % by weight of water.
  • the sodium sulphate solidifies the cellulose spinning solution and the sulfuric acid regenerates the cellulose.
  • the sulfuric acid impregnates the cellulose fibers and the solvent in the fibers comes out, causing neutralization.
  • the wet-spinning process used in this invention can be easily understood by an ordinary skilled person in the art.
  • the regenerated cellulose fiber according to the present invention has a goog strength sufficient to the take-up speed.
  • the cellulose spinning solution has a good spinnability regardless of aging time.
  • the process of preparing a regenerated cellulose fiber in accordance with the present invention prepares a cellulose carbonate derivative using carbon dioxide instead of a cellulose xanthate derivative through reaction of Na-cellulose with carbon disulfide in the viscose process, therefore no harmful to human body. Also, this process may use all the equipments and apparatus of the conventional viscose process.
  • cellulose pulp having molecular weight of about
  • the cellulose pulp was treated with a about 17.5 % NaOH aqueous solution at 3 TJ for 2 hours to prepare Na-cellulose.
  • the Na-cellulose was compressed and exposed to air at 50 TJ to prepare aged cellulose.
  • the aged cellulose was washed with distilled water and filtered six times.
  • the aged cellulose was reacted with carbon dioxide in a pretreating solution in a high pressure reactor to prepare a reacted cellulose.
  • the pretreating solution was a mixed solution of ZnCl 2 and ethanol. In the mixed solution, the weight ratio of ZnCl 2 and ethanol was 1 to 1.
  • the carbon dioxide was used in solid form of dry ice.
  • a cellulose carbonate derivative was prepared from the reacted cellulose by repeating washing and filtration. The washing and filtration was repeated twice.
  • a cellulose spinning solution was prepared by dissolving the cellulose carbonate derivative in a mixed solvent of NaOH and ZnO aqueous solution.
  • a mixed solution of about 10 % NaOH solution and a small amount of ZnO was used.
  • the solution had 3 % by weight of ZnO as per the NaOH aqueous solution.
  • the cellulose carbonate derivative was dissolved at - 10 TJ for about 2 hours.
  • a regenerated cellulose fiber was obtained from the cellulose spinning solution through wet- spinning in a bath. The bath was filled with a solution 10 % by weight of sulfuric acid, 20 % by weight of sodium sulphate and 70 % by weight of water.
  • Examples 1-3 When the regenerated cellulose fiber was prepared, the take-up speed was varied at 10, 15, and 20 rpm, corresponding with Examples 1, 2, and 3, respectively. The regenerated cellulose fibers of Examples 1-3 were dried and strength was measured. The testing results are shown in Table 1.
  • the pretreating solution was varied as shown in Table 3, corresponding with Examples 8-14.
  • spinnability was observed. The spinnability is shown in Table 3.
  • the strength of the regenerated cellulose fiber according to the present invention is good, although it depends on the take-up speed.
  • the spinnability of the regenerated cellulose fiber is also good regardless of the aging time and pretreating solution.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Biochemistry (AREA)
  • Textile Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Artificial Filaments (AREA)

Abstract

Le procédé de préparation de la fibre cellulosique régénérée de l'invention consiste à produire de la Na-cellulose par traitement de cellulose naturelle à l'aide d'une solution aqueuse de NaOH, à faire vieillir la Na-cellulose par exposition de celle-ci à l'air, à enlever l'excédent de NaOH de la cellulose vieillie, par lavage et filtration répétés, à préparer une cellulose de réaction par la mise en réaction de la cellulose vieillie avec du dioxyde de carbone dans une solution de prétraitement, dans un réacteur haute pression, à préparer un dérivé de carbonate de cellulose à partir de la cellulose de réaction, par lavage et filtration répétés, à préparer une solution de filature par dissolution du dérivé de carbonate de cellulose dans un solvant mixte de solution aqueuse de NaOH et ZnO, à procéder à la filature au mouillé de la solution de filature de cellulose, dans un bain. Le procédé de préparation d'une fibre cellulosique régénérée de l'invention consiste à préparer un dérivé de carbonate de cellulose au moyen de dioxyde de carbone à la place d'un dérivé de xanthate de cellulose, par la mise en réaction de Na-cellulose avec du bisulfure de carbone dans le processus au viscose, ce qui est sans danger pour les humains. Par ailleurs, dans ledit procédé on peut utiliser tous les équipements et l'appareil du processus au viscose classique.
PCT/KR1999/000461 1998-09-01 1999-08-18 Nouvelle fibre cellulosique regeneree et son procede de preparation Ceased WO2000012790A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU53079/99A AU5307999A (en) 1998-09-01 1999-08-18 New regenerated cellulose fiber and process of preparing the same

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR1019980035856A KR100275895B1 (ko) 1998-09-01 1998-09-01 셀룰로오스 카보네이트 유도체 및 이를 이용한 재생 셀룰로오스섬유의 제조방법
KR1998/35856 1998-09-01

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104941683A (zh) * 2015-06-09 2015-09-30 南京林业大学 一种纳微ZnO/复合纤维素条状材料及其制备方法
CN108658748A (zh) * 2018-05-11 2018-10-16 武汉轻工大学 一种纤维素降解转化为甲酸的方法
CN108889338A (zh) * 2018-08-22 2018-11-27 南京林业大学 一种ZnO纳米片再生纤维素薄膜复合材料及其制备方法
CN108993605A (zh) * 2018-08-22 2018-12-14 南京林业大学 一种内含片状纳米ZnO的再生纤维素小球及其制备方法
CN109371486A (zh) * 2018-10-26 2019-02-22 含山县领创新材料科技有限公司 一种具有抗菌防霉的服装面料及其制备方法
CN111333735A (zh) * 2020-04-16 2020-06-26 江南大学 一种制备纺丝用低取代度羟乙基纤维素溶液的方法

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2024500164A (ja) 2020-12-22 2024-01-04 バイロキュア インコーポレイテッド 新規な改変レオウイルス及びその用途

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1289548A (fr) * 1969-12-18 1972-09-20
EP0532995A2 (fr) * 1991-09-17 1993-03-24 Wolff Walsrode Aktiengesellschaft Procédé pour la préparation de carbonates de polysaccharides
JPH06279502A (ja) * 1993-03-29 1994-10-04 Asahi Chem Ind Co Ltd カーボネート化セルロース誘導体の製法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1289548A (fr) * 1969-12-18 1972-09-20
EP0532995A2 (fr) * 1991-09-17 1993-03-24 Wolff Walsrode Aktiengesellschaft Procédé pour la préparation de carbonates de polysaccharides
JPH06279502A (ja) * 1993-03-29 1994-10-04 Asahi Chem Ind Co Ltd カーボネート化セルロース誘導体の製法

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104941683A (zh) * 2015-06-09 2015-09-30 南京林业大学 一种纳微ZnO/复合纤维素条状材料及其制备方法
CN108658748A (zh) * 2018-05-11 2018-10-16 武汉轻工大学 一种纤维素降解转化为甲酸的方法
CN108889338A (zh) * 2018-08-22 2018-11-27 南京林业大学 一种ZnO纳米片再生纤维素薄膜复合材料及其制备方法
CN108993605A (zh) * 2018-08-22 2018-12-14 南京林业大学 一种内含片状纳米ZnO的再生纤维素小球及其制备方法
CN108993605B (zh) * 2018-08-22 2020-08-18 南京林业大学 一种内含片状纳米ZnO的再生纤维素小球及其制备方法
CN108889338B (zh) * 2018-08-22 2020-09-01 南京林业大学 一种ZnO纳米片再生纤维素薄膜复合材料及其制备方法
CN109371486A (zh) * 2018-10-26 2019-02-22 含山县领创新材料科技有限公司 一种具有抗菌防霉的服装面料及其制备方法
CN111333735A (zh) * 2020-04-16 2020-06-26 江南大学 一种制备纺丝用低取代度羟乙基纤维素溶液的方法

Also Published As

Publication number Publication date
KR20000018318A (ko) 2000-04-06
AU5307999A (en) 2000-03-21
KR100275895B1 (ko) 2000-12-15

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