JPS61239018A - Continuous production of fiber - Google Patents

Abstract

PURPOSE:To obtain fibers suitable for food, feed, etc., by dissolving a specific polysaccharide in an aqueous solution of NaOH or KOH, extruding the resultant solution into a coagulating solution containing sulfuric acid or hydrochloric acid mixed with an alcohol or acetone, and winding the extruded fibers. CONSTITUTION:A heat coagulable polysaccharide consisting essentially of beta-1,3- glycoside bonds is dissolved in a 0.05-2.0 N aqueous solution of sodium hydroxide or potassium hydroxide to give 5-20wt% polysaccharide concentration. The resultant aqueous solution is then extruded into a coagulating solution containing 1-5 N sulfuric acid or hydrochloric acid mixed with an alcohol or acetone, and coagulated to form a fibrous material, which is wound under tension, as necessary, to give the aimed fibers. The above-mentioned coagulating solution is preferably a mixture solution of dilute sulfuric acid and ethanol.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides continuous fibers with good physical properties of heat-coagulable polysaccharide C (hereinafter sometimes abbreviated as "this polysaccharide") mainly composed of β-1,3-glycosidic bonds. It relates to a method of manufacturing.

Conventionally, fibers of this polysaccharide have been produced by a punching method (Japanese Patent Publication No. 48-44865), but the strength of the resulting fibers was low and the physical properties were not satisfactory.

As a result of intensive research to solve these drawbacks, we discovered a method for continuous production of thin fibers with good physical properties and completed the present invention.

That is, the present invention uses a heat-coagulable polysaccharide mainly composed of β-1,3-glycosidic bonds at a concentration of 5 to 15
Dissolve in a 0.05 to 2.0 N aqueous sodium hydroxide or potassium hydroxide solution to give a concentration of 1 to 5% by weight7, and mix the resulting solution with alcohol or acetone.
A continuous manufacturing method for fibers with good physical properties, characterized by continuously extruding them into a coagulating solution containing specified sulfuric acid or hydrochloric acid, and winding up the coagulated fibers while applying tension as necessary. be.

Examples of heat-coagulable polysaccharides mainly containing β-1,3-glycosidic bonds used in the present invention include alkaline earth metals and polysaccharides produced by bacteria of the genus Agrobacterium. For example, Alcaligenes faecalis var. mikungenes strain 1003
polysaccharide produced by the mutant strain NTK-u (IFo 18140.
8-82673) (hereinafter referred to as "polysaccharide A"), Agrobacterium radiobacter (IFO18127,
Microtechnical Research Institute No. 1167) and its mutant strain [Chou-19
Polysaccharides produced by (IFO18126, Microtechnical Research Institute No. 1166) (Japanese Patent Publication No. 48-32674), Alcaligenes faecalis var myxogenes strain 10
Polysaccharides produced by 03K (Agricultur
al Biological Chemistry
Volume 30, page 196 (1966)).

In the present invention, the present polysaccharide is dissolved in a 0.05 to 2.0 N aqueous sodium hydroxide or potassium hydroxide solution. If the alkali concentration is less than 0.05N, it will not be possible to obtain homogeneous fibers with good physical properties, and if it exceeds 2.0N, the viscosity of the solution obtained by dissolving the polysaccharide will change over time. There is a strong tendency to significantly impair the stability of the present polysaccharide. When dissolved in an alkaline aqueous solution having the above concentration range, it is desirable to perform the fiberization treatment within 48 hours, preferably within 24 hours in order to avoid decomposition of the present polysaccharide.

Next, the polysaccharide is dissolved in an alkaline aqueous solution to a concentration of 5 to 20% by weight. If the concentration is less than 5% by weight, it will not be possible to obtain the strength necessary to continuously wind up the fibers from the coagulation solution, and if it exceeds 20% by weight, the viscosity of the polysaccharide solution will be too high for continuous production. This makes essential defoaming difficult.

It is recommended that the alkaline aqueous solution of this polysaccharide prepared as described above be defoamed under reduced pressure by adding an antifoaming agent (for example, Silicone 5H5510 manufactured by Toyo Rayon Co., Ltd.) as necessary. Preferably, a conventionally known method can be applied to the removal method.

As the coagulating liquid, 1 to 5N sulfuric acid or hydrochloric acid is used. For example, about 1 to 2N sulfuric acid and meta/-/L/,
A high-quality product can be obtained by using a mixture of ethanol, 8 propyl alcohol, or acetone as a coagulating liquid. When the acid concentration of the coagulating liquid is less than 1N, the shrinkage rate of the fiber obtained at a draft ratio of 1 or more is 10 to 30% upon drying, so the practical value of the product is generally low. Also, if the acid concentration exceeds 5N, it will be neutralized (
(gelation) occurs very quickly, resulting in fibers that lack strength and are difficult to wind up, and the washing process to remove excess acid from the resulting product is too burdensome. .

The continuous production method of fibers of the present invention will be explained below.

Pour the pre-blended alkaline spinning solution of this polysaccharide into a spinning solution container inside a pressurized container with a temperature controller, and introduce pressurized gas into the pressurized container from the pressurized gas inlet as necessary. and pressurize. The spinning solution is extruded from a conduit through a constant volume gear pump into a coagulation bath containing a coagulation liquid through a nozzle at a constant discharge linear velocity.

The discharge linear velocity of the spinning solution varies depending on the concentration of the polysaccharide in the spinning solution, the skin ν of the coagulating solution, etc., but it is generally 1 to 30 m /
sin, degree. The fibers formed in the coagulation bath are wound up on a roll drawing machine through hooks, and are preferably deoxidized, e.g. passed through a baking soda-alcohol solution.
Dry using known rayon drying methods and wind on bobbins or skeins. The length of the coagulation bath varies depending on the concentration of the present polysaccharide in the spinning solution, the type and concentration of the coagulation solution, the discharge linear velocity, etc., but is generally 1 to 5 m.

Since the fibers obtained in the present invention are edible, they can be used in the fields of foods, feeds, etc., and can be used, for example, to improve texture by being mixed into artificial structures.

Examples will be shown next, but the present invention is not limited thereto.

Example 1 (1) Preparation of spinning solution Polysaccharide A (water content 5.0%) was added to distilled water to make a uniform slurry, and then sodium hydroxide was poured to give a concentration of 0.1N and the mixture was prepared on a tabletop. The mixture was mixed and dissolved using a kneader (PNV-5). The obtained spinning solution (1 degree of polysaccharide B: 10
%) 2ff was defoamed under reduced pressure of 10 to 151111 Hg for about 2 hours.

・:9) Manufacture of fibers The spinning solution is fed in a fixed amount by a gear pump, and discharged from a nozzle (hole diameter: 0.07, number of holes = 50) at a linear velocity of IQm/m.
A coagulation bath consisting of a mixture of 1N sulfuric acid and ethanol (
Temperature: 21°C9 Bath length: 20 Extruded into (11),
The yarn was spun at a spinning speed of 84,772/m, and the stiffness was wound onto a bobbin.

The physical properties of the obtained fiber were as follows.

Tensile strength (f/d): 0.41 Young's modulus (f/d): 11 Example 2 The same procedure as in Example 3 was carried out except that the concentration of polysaccharide A in the spinning solution was changed to 15%. Note that the discharge linear velocity was 10 m/shoulder in.

The fibers were spun at a spinning speed of IQ m/m, and after being stretched three times with a roll drawing machine, the fibers were wound onto a bobbin.

The physical properties of the obtained fibers are as follows.

Tensile strength y/cl): 2゜0 Young's modulus Cf/
d) =31 Example 3 The alkaline concentration of the spinning solution was 0.75N sodium hydroxide, the concentration of polysaccharide A was 18%, and the other conditions were the same as in Example 3, and the discharge linear velocity was 20 m/m.

The fibers were spun at a spinning speed of 20 m/RiM, stretched 1.5 times using a roll drawing machine, and then wound onto a bobbin.

The physical properties of the obtained fibers are as follows.

Tensile strength l'/d): 0.8 Young's modulus (y/d): 20 Example 4 Fibers were produced in the same manner as in Example 4, except that the spinning speed was 26 m/miR, binding, and the stretching step was omitted. I got it.

Its physical properties are as follows.

Tensile strength 0052 Young's modulus 5.2

Claims (1)

[Scope of Claims] A heat-coagulable polysaccharide mainly composed of 1,β-1,3-glycosidic bonds is heated to a concentration of 0.05 to 2.0N so that the concentration of the polysaccharide is 5 to 20% by weight. of sodium hydroxide or potassium hydroxide, and the resulting solution is continuously extruded into a coagulating solution containing 1 to 5 N sulfuric acid or hydrochloric acid mixed with alcohol or acetone, and the coagulated fibrous material is A method for continuous production of fibers having good physical properties, characterized by winding the fibers while applying tension as necessary. 2. The method for continuous production of fibers according to claim 1, wherein the coagulating liquid is a mixture of dilute sulfuric acid and ethanol.