JPS5830415B2 - Method for producing acrylic fiber with substantially modified texture - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention essentially relates to a method for producing a novel acrylic fiber with improved hand, and more specifically, it contains an organopolysiloxane having an amine group at the end, and when washed, the This invention relates to a method for producing acrylic fibers in which organopolysiloxane does not substantially fall off from the fibers.

Conventionally known acrylic fibers have fiber properties similar to wool among synthetic fibers, and are widely used for various purposes either alone or in blends with various fibers such as wool.

In order to impart a texture more similar to wool, various modified acrylic fibers and post-treatment methods have been proposed.

However, these improved acrylic fibers that have been proposed in the past may lose the essentially excellent performance unique to acrylic fibers if they are imparted with one property, or they lack durability because the properties are only temporarily imparted. There was a drawback.

Among these known methods for improving the texture of acrylic fibers, polysiloxane containing polysiloxane groups (% Kōsho 44-26436)
The method of treating the acrylic fibers with polysiloxane derivatives having amine groups in their side chains (JP-A-49-69999 and JP-A-49-70000) does not impart stickiness to acrylic fibers;
Although they have the characteristic of giving a cashmere-like texture, they all have the disadvantage of being easily damaged by durability, especially washing and dry cleaning.

The present inventors have overcome the above-mentioned drawbacks, namely durability, by producing an acrylic fiber that maintains the excellent fiber performance unique to acrylic fibers, such as dyeing properties and bulkiness, and that has substantially modified the texture itself. The present invention was discovered through intensive research into the law.

That is, the purpose of the present invention is to industrially advantageously produce acrylic fibers that retain the unique properties of acrylic fibers, such as strength and elongation, crimp characteristics, and dyeability, and that have a wool-like feel, especially sliminess. This is to provide a way to do so.

The object of the present invention is to contain an organopolysiloxane having an amine group at the end of the molecular chain, and the absolute content of the organopolysiloxane to the fiber is at least 0.2%.
This can be achieved by a method of producing acrylic fibers that do not substantially shed.

It is important that the organ polysiloxane used in the present invention has an amino group at the end of at least one molecular chain of the polymer chain, rather than a side chain. It is possible to give acrylic fibers a durable, slimy wool texture.

In other words, in the case of organopolysiloxanes that do not have an amino group at the end of the molecular chain, or polysiloxanes that have an amino group but exist in the side chain rather than at the end of the molecular chain, depending on the state of attachment to the fiber, it may be similar to wool. Although it has a texture, it lacks durability and easily loses its wool-like texture when washed or dry-cleaned. It has the disadvantage of impairing the

On the other hand, the organpolysiloxane of the present invention having at least one amino group at the end of its molecular chain has excellent affinity for acrylic fibers, and has excellent durability with an absolute content of 0.2% or more for the fibers. It is characterized by forming fibers with a certain wool texture.

Organopolysiloxanes having an amino group in at least one of the molecular chains of the present invention include various known polysiloxanes, such as dimethylpolysiloxane, methylhydrodiene polysiloxane, methylphenylpolysiloxane, methylamitsubo-9siloxane, or copolymers thereof. At least one molecular chain terminal is an amino group, such as a combination,
For example, trimethoxysilylpropylamine, trimethoxysilylpropylethylenediamino or quaternary
These ammonium salts can be used alone or in combination, and in some cases, a mixture of these organopolysiloxanes in which at least one molecular chain end is an amino group and the above-mentioned known polysiloxanes can be used.

Such an organopolysiloxane can be easily produced, for example, by reacting a polysiloxane having a hydroxyl group at the terminal with an amino group-containing compound as shown in the following formula.

[In the above formula, R, R are alkyl groups, phenyl groups, aminoethyl groups, etc., R1, R2, R3 are alkyl groups, phenyl groups, etc., R4, R5 are -(CR2) n- (however, n
= 1 to 6) methylene group.

[Although the amine group of the organopolysiloxane of the present invention may be a primary amine, secondary amine, tertiary amine, or quaternary ammonium, it is preferable that the organopolysiloxane of the present invention has at least one primary amine. .

In addition, the acrylic copolymer (hereinafter referred to as A) used in the present invention
The N-based copolymer is not particularly limited, and may be an AN-based copolymer containing at least 60 moles of acrylonitrile, but preferably a sulfonic acid group-containing monomer, For example, a copolymer containing an acidic group-containing monomer such as sodium allylsulfonate, sodium methallylsulfonate, and sodium styrenesulfonate as a copolymer component is preferred.

Next, the absolute content in the present invention is JIS-L0844
(1973), the amount of organopolysiloxane adhered to acrylic fibers after repeated washing as specified in Method A-1 is shown in terms of silica (Si) equivalent amount.

The present invention is characterized in that the absolute content of polysiloxane in the acrylic fiber is 0.2% by weight or more based on the weight of the fiber, and the absolute content is 0.2%.
Only by doing the above can it be possible to obtain acrylic fibers with substantially improved texture, which is the object of the present invention.

In other words, if the amount of the organopolysiloxane contained in the fiber is 0.2% or more in terms of Si, the acrylic fiber of the present invention can retain the slimy wool-like texture at least semi-permanently. As long as this absolute amount of adhesion is satisfied, it is not substantially affected by the amount or means of adhesion of organpolysiloxane to the fibers.

Furthermore, in the present invention, the sliminess is expressed by the friction coefficient of the acrylic fiber obtained by the present invention, preferably a spun yarn made using the acrylic fiber.

That is, in the present invention, the friction coefficient refers to a value measured as follows.

First, a spun yarn with a count of 1/48 and a twist coefficient K of about 67 is prepared from acrylic fiber, and two friction bodies are made by winding this spun yarn around a bobbin of 25 mmφ.

Next, the friction angle θ is 2π, the input tension T1 is 5g, and the yarn speed is 2c/
rt/min and 90 cIrL/m1n, the protrusion force T2 is measured, and the friction coefficient μ is determined by the following formula.

T2/T1=eμθ Acrylic fibers having a friction coefficient of 0.17 or less have a wool-like, slimy feel.

Further, in the present invention, the Si equivalent amount indicating the absolute content of organopolysiloxane contained in the acrylic fiber is a value analyzed and determined as follows.

Accurately weigh 0.5 to 1 g of an acrylic fiber sample, put it in a platinum dish, and add 50% of concentrated sulfuric acid (first grade or special grade).
ml platinum dish and heated on an electric heater to gradually carbonize the fibers.

After carbonization, it is further heated to remove SO2 gas, and then placed in an electric furnace and incinerated at 700 to 800°C for about 1 hour.

Next, this ash is melted with an alkali, dissolved in drained water neutralized with hydrochloric acid, and diluted to 100 ml.

A certain amount of this diluted aqueous solution is taken, and 5 ml of 1% HCl and 57711 ammonium molybdate solution are added thereto to develop the color of gray molybdenum blue.

Then, using a solution that was colored without adding a diluted sample solution as a blank target solution, the amount of Si was determined based on a calibration curve by a colorimetric method at a wavelength of 660 mμ.

FIG. 1 is a diagram showing the relationship between the absolute content of organopolysiloxane (Si equivalent value) in the acrylic fiber according to the present invention and the coefficient of friction of the acrylic fiber according to the measurement method.

In FIG. 1, the shaded area is the range that exhibits the slimy texture that is the object of the present invention, but as is clear from the figure, as the absolute content of organopolysiloxane in the fiber increases, the friction coefficient decreases. When the absolute content is 0.2% or more, the friction coefficient becomes 0.17 or less, which corresponds to a slimy wool texture.

However, in the present invention, the absolute content of the organopolysiloxane is 0.2 to 1.0%, preferably 0.2%.
~0.8%, that is, the friction coefficient of the acrylic fiber is 0.8%.
17 or less, preferably about 0.16 or less.

That is, if the absolute content is less than 0.2%, as mentioned above, it is not preferable in terms of improving the hand, which is the objective of the present invention.
If it exceeds 0%, the spinnability of the acrylic fiber will decrease and the product will have a sticky feel, which is not preferable.

Various methods can be considered for producing the acrylic fiber of the present invention, but in order to obtain a fiber that satisfies the condition of the absolute organopolysiloxane content of 0.2% or more stipulated in the present invention, the acrylic fiber It is necessary to incorporate the organopolysiloxane in the manufacturing process, and it is preferable to incorporate the organopolysiloxane into an acrylic fiber in a undried, swollen gel state obtained by wet spinning.

For example, an undried swollen gel yarn obtained by wet spinning an organic solvent solution of the AN-based copolymer is used to form an aqueous emulsion of the organopolysiloxane, such as polyoxyethylene lauryl ether, polyoxyethylene alkylphenol ether, or sorbitan alkyl ether. The swollen gel-like thread is then treated with an aqueous emulsion prepared by using a nonionic surfactant such as a tertiary ammonium compound, a cationic surfactant such as a tertiary ammonium compound, or a polyoxyethylene alkylamine as an emulsifier. For example, it is preferable to introduce the drying and densification method into a hot air dryer at about 130 DEG C. to simultaneously fix the organopolysiloxane to the fibers.

That is, in the present invention, after wet spinning the AN-based copolymer solution, preferably after washing with water, the swollen gel-like yarn is made to contain organopolysiloxane and then dried and densified to advantageously produce the target fiber of the present invention. You can get it.

In this case, the concentration of the aqueous emulsion of the organopolysiloxane is such that the absolute content of the organopolysiloxane is 0.
．． The concentration may be set to 2% or more, but preferably in the range of 0.5 to 1.0%, and the Si content in the alkaline fiber immediately after containing this organopolysiloxane and drying and densifying it. is preferably in the range of 0.3 to 0.5%.

That is, although it depends on the impregnation method and drying and densification conditions, the acrylic fiber containing organopolysiloxane having an amino group at the end of the molecular chain used in the present invention has significantly better washing resistance than conventionally known silicone-treated acrylic fibers. However, as the concentration of organpolysiloxane in the treatment bath increases, there is a general tendency that the amount of organpolysiloxane shed during washing increases. About 40% or more of the organopolysiloxane is effectively retained after washing about three times.

For example, FIG. 2 is a diagram showing changes in organ polysiloxane content (Si equivalent value) in acrylic fibers obtained according to one embodiment of the present invention and known silicone-treated acrylic fibers when washed. , In the figure,
1 has a concentration of the organopolysiloxane of the present invention in the treatment bath of 20%, 2 has a concentration of 1%, 3 has a concentration of 0.5%, and 4 has a concentration of 0.2%.
5 is a comparison acrylic fiber treated with a known silicone treatment bath.

As can be seen from the figure, the acrylic fiber according to the present invention has good affinity for organopolysiloxane fibers, has excellent washing resistance, and has a polysiloxane content of 0.2% or more after washing three times. It can be seen that it holds well.

That is, the acrylic fiber according to the present invention is distinguished from known silicone-treated acrylic fibers in that the organopolysiloxane contained in the fiber has significantly greater resistance to shedding.

That is, in known silicone-treated acrylic fibers, regardless of the silicone content contained in the fibers, most of the silicone is removed by the above-mentioned washing, and the absolute content of organopolysiloxane specified in the present invention is reduced. 0.
However, in the acrylic fiber according to the present invention, the absolute content of organopolysiloxane is 0.2% or more. In this case, the absolute content never becomes substantially less than 0.2%.

Moreover, the acrylic fiber obtained by the present invention with an absolute content of 0.2% or more not only exhibits a slimy, wool-like texture, but also retains the excellent dyeing properties of acrylic fiber, Moreover, it has the characteristic of exhibiting excellent flexibility even without substantial treatment with a fabric softener.

The fact that this softening finish is not required is an extremely excellent feature considering that many commercially available softeners are said to be one of the causes of sewage in rivers and are regulated to prevent pollution.

The present invention will be specifically explained below using Examples.

Example 1 94.2 mol% of acrylonitrile (hereinafter referred to as AN), 5.5 mol% of methyl acrylate (hereinafter referred to as MA), and 0.3 mol% of sodium methallylsulfonate (hereinafter referred to as 5AS) were mixed in dimethyl sulfoxide (DMSO) as a solvent. 0.08 m71Lφ of the AN-based copolymer solution obtained by polymerization by solution polymerization,
It was discharged into a DMS055% aqueous solution through a 10,000 hole nozzle to form a thread.

This yarn was stretched 6 times in a 30% DMSO aqueous solution and steam, then washed with water until the DMSO content in the yarn became Q, 3% or less, then subjected to relaxation heat treatment with steam, and passed through squeezing rollers until the water content reached 80. % water-swollen yarn was prepared.

This water-swollen yarn was immersed in the various organopolysiloxane emulsions shown in Table 1 (shown in which the molecular chain end is an amine group) and squeezed again with a squeezing roller to a water content of 100%.
The material was introduced into a hot air dryer at 30° C. to be dried and densified, and subjected to crimping and heat treatment.

All of the organopolysiloxane-containing acrylic fibers thus obtained had a slimy texture similar to cashmere, and their Si content, washing resistance, dyeability, and strength and elongation were as shown in Table 2. .

Comparative Example 1 As shown in Table 3, the organopolysiloxane used in Example 1 was polysiloxane with an epoxy group or methyl group at the molecular chain end, polysiloxane with an OH group at the end and an amine group in the side chain, etc. As shown in Table 3, the acrylic fibers obtained when treated with a material that does not have amino groups exhibited some sliminess and a texture similar to wool before washing. After washing three times, most of the polysiloxane contained in the fibers fell off, the texture was not maintained, and durability was significantly lacking.

However, the emulsifier is POEFtE, and the concentration is 2.0%.
It is.

Processing Bath Concentration Example 2 In Example 1, dimethylpolysiloxane (molecular chain-terminated ethylenediamine) was used as the organopolysiloxane, and the polysiloxane concentration in the aqueous emulsion treatment liquid was as shown in Table 4 (modified below). Four types of acrylic fibers with different organopolysiloxane contents were prepared and the washing resistance, texture, Si content, etc. were measured in the same manner as in Example 1, and the results shown in Table 4 were different.

Furthermore, Fig. 2 is a diagram showing the change in S1 content depending on the number of washings of four types of acrylic fibers with different organopolysiloxane contents treated with baths with different concentrations in the treatment e, and in the figure, 1 is 20%. , 2411 shows the change in Si content depending on the number of washings of acrylic fibers treated with a treatment bath containing 1.0% polysiloxane, 3 0.5%, 4 0.2%, and 5 shows the change in Si content due to washing of acrylic fibers treated with a treatment bath containing 2.0% dimethylpolysiloxane having no terminal amino groups.

As can be seen from the figure, the acrylic fiber according to the present invention has excellent washing resistance and retention of polysiloxane, and the treatment bath concentration is 0.
If it is 5% or more, it can be seen that the absolute content of organopolysiloxane is Q, 2% or more in terms of 81.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between the friction coefficient of the acrylic fiber according to the present invention and the amount of organopolysiloxane contained in the fiber (Si equivalent value), and FIG. FIG. 3 is a diagram showing changes in Si equivalent value in the acrylic fibers after washing the acrylic fibers.

Claims (1)

[Claims] 1. When drying and densifying a swollen gel-like thread obtained by wet-spinning a solution of an acrylic copolymer containing at least 60 moles of acrylonitrile, molecular chains are added to the swollen gel-like thread in advance. Organpolysiloxane having an amine group is added to at least less than one of the fibers, and the siloxane is contained in the densified yarn in an amount of about 0.2 to 1.0% (absolute content). A method for producing acrylic fiber with a modified texture.