JPS5953948B2 - Processing method for aromatic polyamide synthetic fibers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating aromatic polyamide synthetic fibers.

More specifically, after the drawing process, aromatic polyamide fibers are treated with a treatment agent containing a specific oil component in a suitable proportion, thereby imparting excellent electrostatic properties to the fibers, resulting in aromatic polyamide fibers with excellent spinning stability. The present invention relates to a fiber processing method for providing polyamide synthetic fibers.

Aromatic polyamide synthetic fibers have been recently praised as flame-retardant fibers because they have excellent heat resistance and flame resistance.

However, unlike polyester fibers or nylon fibers, it has a very high melting point, so it cannot be formed into yarn using normal melt spinning methods.

Therefore, wet or dry spinning methods are usually employed.

Moreover, in the spinning process, the wet method uses a coagulation bath of calcium chloride, which means that lucium chloride remains in the polymer, and the dry method uses lime to neutralize the hydrochloric acid produced by the reaction between acid chloride and amine. is added, but
As a result, lucium chloride is generated, and in order to further stabilize the polymer solution, lucium chloride is actively added to the polymer solution, and then dry spinning is carried out.

Therefore, in either method, after the yarn is formed, washing with water is performed to remove the lucium chloride present in the polymer.

However, it is nearly impossible to completely eliminate this lucium chloride remaining in the polymer during the yarn manufacturing process, and some calcium ions inevitably remain even after washing with water.

This residual lucium ion has a major negative impact on the oil treatment process.

For example, anionic activators commonly used as electrical training agents, especially sulfonate-based or phosphate-based compounds, undergo ion exchange and turn into calcium salts that are insoluble in water, so the original performance cannot be obtained and excess oil adheres. There is also the issue of having to do this.

Furthermore, since this type of reaction occurs in an oil deposition bath, the aqueous oil solution, which should originally be obtained in a transparent state, is replaced by calcium ions, which turns the liquid into an oil cloud, and as the reaction progresses further, a scum-like substance is formed. floating in the air, which has an extremely negative impact on the stability of the yarn manufacturing process.

Further, precipitated scum may adhere to the fibers and become foreign matter and adhere to rollers and the like during the secondary processing process, particularly the spinning process, causing winding.

Furthermore, it may cause needles and other objects to rust during the secondary processing process.

In addition, aromatic polyamide fibers are originally highly heat-resistant fibers, and because they are used for applications that take advantage of their characteristics, they are sometimes subjected to extremely high temperature heat treatment in the secondary processing process, but the oil agent attached to them may If the heat resistance is extremely low, the appearance may deteriorate due to coloring, or the oil agent may volatilize due to heat, which may even become a hindrance, so a fairly high heat resistance is required.

That is, it goes without saying that it is preferable that excellent antistatic properties be maintained without any discoloration even after heat treatment.

Furthermore, as is well known, it is extremely difficult to impart antistatic properties to aromatic polyamide fibers compared to polyester fibers, and nonionic activators are not suitable for secondary processing processes such as spinning processes. It is difficult to obtain such antistatic properties, and the above-mentioned constraint that even an anionic activator has reactivity with calcium ion makes the range of oil-based properties that can be specifically selected extremely limited.

Moreover, if the cationic activator is used as the main ingredient, disadvantages such as rusting of the needle during the secondary processing step and rusting due to calcium ions are often promoted.

In addition, there is also the problem of heat resistance.

There are also methods using amphoteric activators, but these tend to cause rust on the needles, are heat resistant, and have high hygroscopic properties, resulting in poor spinnability.

In order to improve these shortcomings, treatment agents based on alkyl phosphate-based antistatic agents, which have rust prevention and antistatic properties, have been used as main ingredients, and even treatment agents that have the drawbacks of alkyl phosphate-based antistatic agents have been developed. Oil agents containing alkyl phosphate compounds as main components into which polyoxyethylene chains have been introduced have been proposed in order to reduce reactivity with Schramm ions and improve electrostatic properties.

In this case, unlike alkyl phosphates, it does not form a floc-like scum upon reaction with lucium ions; however, even if it is transparent in the initial stage, it immediately tends to become cloudy, and the amount of adhesion does not increase considerably. It has the disadvantage of not being effective.

In addition, if the amount of adhesion is increased, spinnability decreases, roller wrapping increases, and productivity becomes extremely low.

On the other hand, sulfate compounds have been well known for a long time as antistatic agents with low reactivity with calcium ions, and are often used for spinning natural fibers, rayon, etc., but they are inferior in heat resistance and are used in aromatic polyamides. The fibers cannot withstand any use as they are.

As a result of intensive studies in order to eliminate these drawbacks, the present inventors have found that by applying a treatment agent containing a specific oil component as shown below to aromatic polyamide synthetic fibers after the drawing process, the oil agent itself is It reduces the calcium ion exchangeability of the fiber as much as possible, improves the antistatic properties of the fiber, does not cause coloration during heating, and has a very low tendency to reduce the amount of oil adhesion due to heating. The present invention has been completed by achieving an extremely superior aromatic polyamide synthetic fiber.

That is, the present invention provides aromatic polyamide synthetic fibers with the general formula (1) % formula % (1) [wherein R is a saturated or unsaturated alkyl group having 8 to 18 carbon atoms, P =1~iox represents Na, K.

] and general formula (2) [wherein R is a saturated or unsaturated alkyl group having 8 to 18 carbon atoms, R', R'' is a hydrogen atom or a methyl group, and n+m=1 to 10; A positive integer 1 is 1 or 2,
M represents Na, K5Li, ammonium, or an organic amine residue.

The copolymerization here may be random or block.

] and has an acid value of 0 to 50, and the component ratio of formula (1) and formula (2) is (1)
Formula/(2) formula = 5:1 to 1:1, and the components of formula (1) and (2
This method consists of a method for treating aromatic polyamide-based synthetic fibers, which is characterized in that a treatment agent comprising at least 60% by weight of the total oil agent composition is applied to the fibers.

The aromatic polyamide synthetic fiber in the present invention includes:
Examples include:

(1) A condensed polyamide of a dicarboxylic acid having an aromatic ring and a diamine having an aromatic ring.

For example, it may be a homopolymer consisting of a type of dicarboxylic acid or a type of diamine using terephthalic acid, isophthalic acid, etc. as a dicarboxylic acid, metaphenylene diamine, xylylene diamine, etc. as a diamine, and a dicarboxylic acid component and a diamine. One or both of the components may be a copolymer composed of two or more kinds of compounds.

Typical examples include polymethaphenylene isophthalamide, polymethaxylylene diamine terephthalamide, and copolymers of metaphenylene, diamine, isophthalic acid, and terephthalic acid.

(2) Polyamide condensed with aminocarboxylic acid having an aromatic ring For example, the aminocarboxylic acid may be a homopolymer of only one type using para-aminobenzoic acid, para-aminomethylbenzoic acid, etc. It may also be a copolymer of carboxylic acid.

A typical example is a condensate of para-aminobenzoic acid.

(3) A typical example of a polyamide obtained by copolymerizing the above (1) and (2) is a polyamide obtained by condensing the three components of metaphenylenediamine, isophthalic acid, and para-aminobenzoic acid.

In addition, the compound of general formula (1) used in the present invention is a commonly known sulfate compound, R-0℃CH2CH2O+PSO3X [However, R is a saturated or unsaturated alkyl group having 8 to 18 carbon atoms, and P is an average polymerization degree, P=1 to 10, X is Na
, K.

] Specifically, it consists of a sodium or potassium salt of a sulfate of a compound obtained by reacting a higher alcohol with ethylene oxide, and P is preferably 2 to 6.
is optimal.

For example, POE (average number of added moles of polyoxyethylene)
If shown as POE (1) octyl sulfate),
POE (2) Tesyl sulfate-1-, POE (2) Laryl sulfate, POE (3) Cetyl sulfate POE (5) Oleyl sulfate), POE (10)
Examples include sodium or potassium salts such as stearyl sulfate.

These POE (P mol)-added sulfates have long been known as surfactants with extremely low calcium ion exchange properties due to their high hard water resistance. It is a uniquely stable compound, and its transparent aqueous solution does not become cloudy.

Therefore, it has very stable antistatic properties.

However, although it has this great feature, it is not practical as it is because it causes severe discoloration when heated, and the loss on heating is extremely large, resulting in a very large drawback in terms of thermal stability.

On the other hand, there are alkyl sulfates that do not have polyoxyethylene chains added, but they are excluded from the present invention because of their solubility, thermal stability, and poor cohesiveness during the spinning process. .

The present inventors have made use of this feature of low calcium ion reactivity, and have carried out various studies in order to significantly improve thermal stability, further improve the electrostatic properties of aromatic polyamide synthetic fibers, and improve spinnability. The result is general formula (2), [wherein R is a saturated or unsaturated alkyl group having 8 to 18 carbon atoms R/, R11 is a hydrogen atom or a methyl group, n0m is a positive integer of 1 to 10, ■ indicates 1 or 2, M is Na, K, Li, ammonium.

Indicates an organic amine residue.

The copolymerization here may be random or block.

] By using polyoxyalkylene-modified phosphate ester salts having an acid value of 0 to 50 in combination with general formula (1), thermal coloring and heating weight loss can be achieved without any increase in calcium ion reactivity. We have found that it is possible to significantly reduce the

However, it is difficult to reduce calcium ion reactivity with polyoxyalkylene-modified phosphate alone;
In fact, in the transparent aqueous solution of general formula (2), alkyl phosphate
Although it does not reach the level of particles that have grown as scum like the salts from No. 1 to 2, it tends to become cloudy immediately and cannot be used alone.

On the other hand, alkyl phosphate salts without a polyoxyalkylene group have extremely high calcium ion reactivity and turn into floc-like scum almost instantly, even when used in combination with general formula (1). It is not something that can be put to practical use.

In addition, these polyoxyalkylene-modified and phosphate ester salts are not suitable for use alone because of their large weight loss upon heating.

, Therefore, as can be seen from these facts, the general formula (1
) It is difficult to clearly explain why the combination with the general formula (
There is no doubt that the excellent synergistic effect with 1) gives aromatic polyamide fibers excellent properties.

These compounds are usually obtained by known methods, but phosphoric acid ester salts are obtained by reacting phosphoric anhydride with a polyoxyalkylene compound having a terminal hydroxyl group in which ethylene oxide or both ethylene oxide and propylene oxide are simultaneously added to a higher alcohol. can be obtained.

In the formula, n+m is a positive integer of 1 to 10. These phosphate ester salts are obtained as a mixture of 1 or 2 in the formula, that is, a mixture of mono-substituted and di-substituted phosphoric esters. , ammonium or organic amines as water-soluble salts.

Among these, alkali metal salts such as sodium and potassium are preferred.

To give a more specific example, the number in parentheses is the number of moles of polyoxyethylene group, POE (1) lauryl phosphate, POE (3) lauryl phosphate, PO
E(5) oleyl phosphate and POE(10)
Furthermore, the sum of the number of moles added by reacting both ethylene oxide and propylene oxide with a higher alcohol such as octyl alcohol, lauryl alcohol, or cetyl alcohol is 10 or less, and the terminal Examples include sodium or potassium salts of phosphate esters synthesized using denatured alcohols having hydroxyl groups.

Furthermore, the degree of neutralization of these phosphoric acid ester salts is such that the acid value is O.
The acid value of O means that it is completely neutralized, and the acid value of 50 means that 50% of the phosphoric acid ester is neutralized.

The degree of neutralization is relatively good as the acid value becomes 0, but the degree of neutralization is preferably 10 to 4 in order to prevent the coefficient of friction and hygroscopicity of the fiber surface from becoming excessive.
A value of about 0 is preferably used.

In the present invention, the compounding ratio of the compound of general formula (1) and the compound of general formula (2) must be in the range of 5:1 to 1:1 and at least 60% by weight in the total oil composition.

That is, the compound of general formula (1) is used as a main component, and the compound of general formula (2) is used in combination therewith.

In terms of reactivity with calcium ions, general formula (2)
The amount of the compound of formula (1) does not exceed the amount of the compound of general formula (1).

When the amount of the compound of general formula (2) increases, the calcium ion reactivity increases, leading to a lack of stability.

In addition, in order to greatly reduce the tendency for the amount of adhesion to decrease due to coloring due to heat or heating, the general formula (1) is used.
The compounding amount of the compound of general formula (2) is 5:
A ratio of 1 to 1:1 is preferred.

When the ratio is 5:1 or more, the coloring tendency becomes markedly large and there is a strong tendency for yellowing or browning.For example, when the compound of general formula (1) is used alone, the coloring becomes dark black.

In addition, the weight loss due to heating increases, and when the raw cotton is heat-treated, its conductivity decreases due to thermal decomposition.

Further, in order for the composition of the present invention to exhibit the effects of the present invention, the total oil composition must be at least 60% by weight, but other components are not particularly limited.

In other words, it is a component that does not reduce the effect of the present invention, further improves spinnability in the secondary processing process, has no reactivity with calcium chloride, and improves and promotes electrophoresis. May be used together.

For example, leveling agents and emulsifiers, cationic activators, amphoteric activators, other anionic activators, and nonionic activators can be used.

In order to particularly improve the tightness of the wrap of raw cotton made of aromatic polyamide fibers, nonionic activators and the like are often used in combination.

The treatment agent of the present invention may be applied to aromatic polyamide fibers at any stage after stretching by using a roller method, dipping method, spray method, etc. as a 1 to 5% aqueous solution.

The amount of adhesion of the compound of the present invention to the fiber is 0.1~
By depositing 0.2%, stable electrophoretic properties can be obtained, and these effects are maintained even after heat treatment, and almost no coloration is observed.

The present invention will be specifically explained below with reference to Examples, in which all "%" indicates "% by weight" and "parts" indicate parts by weight.

As an evaluation method, the transparency of the aqueous solution in the treatment tank in which the tow was treated was qualitatively judged based on the turbidity of the solution in the treatment tank after one hour.

○ Collect 2g of coloring oil into a stainless steel plate and add 140
After heating at ℃ for 3 hours and cooling, the coloring state of the oil remaining on the stainless steel plate was visually determined.

○Measurement of loss on heating 2g of the blended oil was collected in a stainless steel dish, treated in the same manner as for the coloring properties above, weighed after cooling, and those with a weight change of more than 15% before and after the heating treatment were marked as ×, and 10%. The following items were graded into 3 grades, with ○ being the middle one being △.

○Card characteristics (spinning properties) 25℃ x 55%RH, 300 gel/yard x 12r
, I). Those with no problems, including clogging of the coiler tube during carding and sliver dripping between the calender roll and the coiler, were evaluated as ○, and those with poor card characteristics were evaluated as ×.

○ Streak characteristics (spinning properties) 300 gel/yard at 25℃ x 55%RH for 180m
The fibers were passed through a filament machine at a spinning speed of /mm, and from the viewpoint of clogging of the filament roller at the time of unwinding and winding of the filament roller, those in the overall good direction were evaluated as ○, and those in poor condition were evaluated as ×.

Examples 1 to 4 Comparative Examples 1 to 4 Polymetaphenylene isophthalamide obtained by polymerization of m-phenylene diamine and isophthalic acid chloride was extruded into an aqueous solution of rhusium chloride and solidified12.
A tow of 80,000 tensile strength was prepared, and after washing with water, it was stretched 3.2 times under water, then dried and heat treated at 340°C, and then a treatment agent shown in Table 1 was applied to the crimped shaft at room temperature. The tow was then crimped and cut to obtain short fibers of 2 denier x 51 mm.

The amount of treatment liquid attached to the fibers was 0.15% in each case.

(Good) ○〉○〜△〉△＞x＞xx (Bad) Example 5~
7 Comparative Examples 5 to 7 Polymetaphenylene isophthalamide obtained by polymerization of m-phenylene diamine and isophthalic acid chloride was extruded into an aqueous solution of rhusium chloride and coagulated12.
A tow of 80,000 tensile strength was prepared, and after washing with water, it was stretched to 3.2 times its original size in boiling water, dried, and heat treated at 340°C. The tow was then crimped, and the tow was cut to obtain short fibers of 2 denier x 51 mm.

The amount of treatment agent attached to the fibers was 0.15% in all cases.

Regarding spinnability, the quality of the carding and filament processes was relatively compared.

Claims (1)

[Claims] 1. General formula (1) % formula % (1) [However, R is a saturated or unsaturated alkyl group having 8 to 18 carbon atoms, P= 1-10. X represents Na or K. ] and general formula (2) [wherein R is a saturated or unsaturated alkyl group having 8 to 18 carbon atoms, R' and R'' are a hydrogen atom or a methyl group,
n0m is a positive integer from 1 to 10, l is 1 or 2, and M represents Na, K, Li, or ammonium organic amine residue. The copolymerization here may be random or block. ] and has an acid value of 0 to 50, and the component ratio of formula (1) and formula (2) is (1)
Formula/(2) Formula-5:1 to 1:1, the components of formula (1) and (2
1. A method for treating aromatic polyamide synthetic fibers, which comprises applying to the fibers a treatment agent in which the sum of the components of the formula (2) is at least 60% by weight of the total oil composition.