DD253261A1 - METHOD FOR PRODUCING CELLULOSE GENERATOR FIBERS - Google Patents

Abstract

The invention relates to the production of viscose fibers with high wet modulus and low elongation. The resulting fibers with cotton-like properties make it possible to process into yarns, possibly mixed with synthetic fibers, using modern spinning processes. According to the invention, the viscose, depending on its state of maturity and the spinning bath composition, a corresponding modifier combination of an amine of the formula I CnH2n1-N (CH2CH2O) x H (CH2CH2O) yHI with n4 to 20 and xy6 to 20 and a polyalkylene oxide of the formula II HO (CHRCH2O ) nHII with RH or CH3 and n20 to 60 and optionally a secondary aliphatic amine.

Description

Field of application of the invention

The invention relates to a process for the production of viscose fibers with low elongation and high wet modulus. These fibers, spun as continuous yarn, are suitable for pure and mixed processing, preferably with polyester fibers, in place of cotton or blended with cotton using highly effective technologies in the textile industry in a wide range of applications from sub-knit garments to engineering fabrics.

Characteristic of the known state of the art

It is known that for the production of fibers of regenerated cellulose with low elongation, high wet modulus and high strength viscoses with a content of 5.5 to 8Ma .-% alpha-cellulose, 5 to 7 wt .-% sodium hydroxide and 31 to 38 Ma .-%, based on alpha-cellulose, carbon disulfide are spun with the addition of modifiers in spinning baths having a composition of 45 to 80g / l sulfuric acid, 45 to 65 g / l zinc sulfate and 90 to 150 g / l sodium sulfate. The temperature range is preferably from 30 to 4O ⁰ C.

The tows drawn off from the spinning bath are subjected to drawing in a hot, sulfuric acid secondary bath, then preferably fixed in a weakly sulfuric, hot third bath without tension, cut into stacks and the staple fibers are aftertreated in a known manner. (DD-PS 77040, AT-PS 287906, US-PS 3632718) A modifier is added to the viscose which retards the regeneration process of the sodium cellulose xanthogenate and thereby allows a higher degree of stretching, thereby imparting the resultant fiber with improved mechanical properties.

In the majority of two different mixtures consisting of ethoxylated amines and polyethylene glycols, ethoxylated fatty acids or fatty alcohols and polyethylene glycols or polyamines possibly together with amines and polyethylene glycols are used according to their different modifying effect during the regeneration process of viscose (DE-OS 1 949325, AT-PS 201226, DE-OS 1494598, SE-PS 181152, DE-OS 2151345). When using tri-mixtures, those of dimethylamine or cyclohexylamine, polyethylene glycol and zinc compounds or ethoxylated phenols are known (AT-PS 318125, US-PS 3434913).

Although these processes have succeeded in producing fibers with good strength properties, this is only possible within narrow technological limits and a modifier blend oriented thereon.

Object of the invention

The aim of the invention is to produce viscose fibers with high loop tearing force, high Naßmodulwerten and low elongation without great technical effort with changed Spinnbadzusammensetzungen.

Explanation of the essence of the invention

The object of the invention is to develop processes which make it possible to economically and effectively obtain such viscose fibers by the use of special modifier mixtures depending on the ripeness state of the spinning viscose and the spinning bath applied.

According to the invention, the method by spinning a viscose with a content of 5.5 to 8 wt .-% alpha-cellulose and 5 to 7 wt .-% sodium hydroxide and, based on alpha-cellulose, 31 to 38 wt .-% carbon disulfide and 2.5 to 5.5% by weight of a modifier mixture in a spin bath with 45 to 80 g / l sulfuric acid, 45 to 65 g / l zinc sulfate and 90 to 150 g / l sodium sulfate, stretching the coagulated threads by 107 to 140% in a sulfuric acid, at a temperature of 90 to 96 ° C held stretching bath and preferably stress-free relaxation in a downstream, slightly sulfuric acid fixer at 90 to 96 ° C.

The viscose is used as a modifier, a combination of 0.5 to 2.5 wt .-%, based on alpha-cellulose, of an amine of formula I.

G.

'(GH ₂ GH ₂ O) -H

with η = 4 to 20, preferably 16 to 18 and χ + y = 6 to 20, preferably 10 to 16 and 0.5 to 2.5 wt .-%, based on alpha-cellulose of a polyalkylene oxide of the formula II

HO- (CHRCH ₂ O) _n -H with R = H or CH ₃ and η = 20 to 60 added.

If appropriate, 0.5 to 2% by weight, based on alpha-cellulose, of a secondary aliphatic amine are added.

In a particular embodiment, the propylene oxide modified polyethylene oxide component of general formula III

R ₁ - (OCH ₂ CH ₂ ) _x -O-CHCH ₂ OCH ₂ CH-O- (CH ₂ CH ₂ O) _y -R 2 III

CH ₃ CH ₃

wherein χ + y is a number from 4 to 18 and R ₁ and R _{2 are} blockcopolymer radicals of the formulas IVa and IVb

- (CH ₂ CHO) _m - (CH ₂ CH ₂ O) "- H IVa

CH ₃

- (CH ₂ CHO) _k - (CH ₂ CH ₂ O) | -H IVb

CH ₃

in which m + is not a number from 0 to 5 and η + I is a number from 14 to 35. This solves significant problems in preparing a meterable, liquid modifier mixture. At a gamma value of the cable to be spun from 20 to 28 and an EZ ₃₀ viscosity of 70 to 85, the spin bath composition at a temperature of 30 to 38 ⁰ C 45 to 65g / l sulfuric acid, 45 to 65 g / l zinc sulfate and 90 to 150 g / l of sodium sulfate and the sodium trithiocarbonate content of the viscose 1.1 to 1.7 Ma .-%. With a gamma value of about erspinnenden cable 20 to 28 and a SR ₃₀ -Reifezahl the viscose 95-103 should Spinnbadzusammensetzung at einerTemperaturvon 30 to 38 ⁰ C 60 to 80g / l sulfuric acid, 50 to 65g / l of zinc sulphate and 90 to 150 g / l sodium sulphate and the sodium trithiocarbonate content in the viscose are from 0.5 to 0.9% by mass. Surprisingly, it has been found that, depending on the ripeness state and the content of the spin viscose sodium trithiocarbonate, it is possible to produce viscose fibers of low elongation, high strength and high wet modulus, even with different spin bath composition, depending on the choice of modifier, which do not differ in their utility properties.

embodiments

The process of the invention will be explained in more detail in the following examples. Cellulosergeneratfasern are produced with good force-elongation properties in the wet state, measured as wet modulus, low brittleness, measured as loop tearing force and elongation under the following spinning conditions: Viscose from leaf or softwood pulps containing 5.5 to 8 wt .-% alpha Cellulose, 5 to 7% by mass of sodium hydroxide, 31 to 38% by mass, based on alpha-cellulose, carbon disulfide and a viscosity of 80 to 110s falling ball vertically at 30 to 38 ⁰ C in a corresponding precipitation bath with the indicated compositions spun. The cable is then stretched in a secondary bath at 96 ° C by at least 107%, led under relaxation in a downstream fixer at 96 ° C and post-treated in a known manner.

Example 1

A viscose is usually prepared from a Buchensulfitzellstoff in which contains 6Ma .-% Aipha-cellulose and 6Ma .-% sodium hydroxide and has a viscosity of 90s ball drop. The following modifier amounts, based on alpha-cellulose, are stirred into this viscose:

1.5Ma .-% of an amine of formula I with η = 16 and χ + y = 13 and 2 Ma .-% of a polyalkylene oxide of the formula II with R = H

The viscose is matured so far that it has a maturity EZ ₃₀ of 100 and a sodium trithiocarbonate content of 0.64 during spinning. In this state it is spun into a spinning bath of composition 78 g / l sulfuric acid, 120 g / l sodium sulphate, 65 g / l zinc sulphate at a temperature of 34 ° C. The maximum drawability under these conditions is 125% at a final take-off speed of 23 m / min.

The resulting fibers have the following textile-physical characteristics:

Fineness: 0.15 tex

Yield-based breaking strength, dry: 365mN / tex

fineness-related shear breaking strength: 72mN / tex

Wet module: 1068mN / tex

Elongation, dry: 16% '

Example: 2

A viscose made of a spruce sulphite pulp having a composition of 7% by weight of alpha-cellulose and 5.3% by weight of sodium hydroxide and having a viscosity of 95s falling ball is usually prepared.

The following modifier amounts, based on alpha-cellulose, are stirred into the viscose:

1.5% by weight of an amine of the formula I where η = 17 and x + y = 13

1.5Ma .-% of a polyalkylene oxide of the formula III with χ + y = 9 and radicals of the formulas IVa and IVb with m + k = 1 and η + 1 = 21 and

0.6% by weight of dimethylamine.

The viscose is matured so far that it has a maturity EZ ₃₀ of 76 and a sodium trithiocarbonate content of 1.61 Ma .-% during spinning. In this state, it is spun into a spinning bath of the composition 50 g / l sulfuric acid, 55 g / l zinc sulfate, 150 g / l sodium sulfate at a temperature of 32 ⁰ C. The maximum drawability is 120% at a final take-off speed of 23 m / min.

The resulting fibers have the following textile-physical characteristics:

Fineness: 0.149 tex Yield-based breaking strength, dry: 360 mN / tex fineness-related loop tearing force: 78 mN / tex wet modulus: 1080 mN / tex Stretching, dry: 17%

Claims (4)

A process for producing low elongation, high wet modulus regenerated cellulose fibers by spinning a viscose containing 5.5 to 8% by weight of alpha-cellulose and 5 to 7% by mass of sodium hydroxide and, based on alpha-cellulose, From 31 to 38% by mass of carbon disulfide and from 2.5 to 5.5% by weight of a modifier mixture into a spin bath containing 45 to 80 g / l sulfuric acid, 45 to 65 g / l zinc sulfate and 90 to 150 g / l sodium sulfate, stretching the coagulated filaments um.107 to 140% in a sulfuric acid, maintained at a temperature of 90 to -96 ⁰ C stretching and preferably stress-free relaxation in a downstream, weakly sulfuric fixer at 90 to 96 ⁰ C, characterized in that the viscose as a modifier combination from 0.5 to 2.5% by weight, based on alpha-cellulose, of an amine of the formula I. , (CH ₂ CH ₂ O) _x -H with η = 4 to 20, preferably 16 to 18 and
χ + y = 6 to 20, preferably 10 to 16,
0.5 to 2.5% by weight, based on alpha-cellulose,
a polyalkylene oxide of the formula II HOhCHR-CH ₂ -O) _n H II with R = H or CH ₃ and η = 20 to 60 and optionally 0.5 to 2 wt .-%, based on alpha-cellulose, of a secondary aliphatic amine is added, wherein the viscose to be spun an EZ ₃₀ -Reifezahl 70 to 103 and a Natriumtrithiocarbonatgehalt of 0.5 to 1.7 Has Ma .-% and the cable to be spinned has a gamma value of 20-28. 2. The method according to claim 1, characterized in that the modified with propylene oxide polyethylene oxide of the general formula III _# R ₁ - (OCH ₂ CH ₂ ) _x -O-CHCH ₂ OCH ₂ CH-O- (CH ₂ CH ₂ O) _y -R ₂ III CH ₃ CH ₃ wherein χ + y is a number from 4 to 18 and R ₁ and R _{2 are} blockcopolymer radicals of the formulas IVa and IVb - (CH ₂ CHO) _n HCH ₂ CH ₂ O) _n -H IVa , CH ₃ - (CH ₂ CHO) HCH ₂ CH ₂ O) ₁ -H IVb - OH ₃ · and m + is not a number from 0 to 5 and η + I is a number from 14 to 35, is used. 3. Process according to claims 1 to 2, characterized in that at a gamma value of the cable to be spinned from 20 to 28 and at a EZ ₃₀ -Reifezahl the viscose from 70 to 85, the spin bath composition at a temperature of 30 to 38 ° C 45 to 65 g / l sulfuric acid, 45 to 65 g / l zinc sulfate and 90 to 150 g / l sodium sulfate and the Natriumtrithiocarbonatgehalt the viscose is 1.1 to 1.7Ma .-%. 4. The method according to claims 1 to 2, characterized in that at a gamma value of the cable to be spun from 20 to 28 and at an EZ ₃₀ -Reifezahl the viscose from 95 to 103, the spin bath composition at a temperature of 30 to 38 ⁰ C 60 to 80 g / l sulfuric acid, 50 to 65g / l zinc sulfate and 90 to 150g / l sodium sulfate and the sodium t-rithiocarbonatgehalt in the viscose at 0.5 to 0.9 wt .-% is.