JPS6256264B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a processing agent for aromatic polyamide synthetic fibers having excellent spinnability. Specifically, the present invention relates to a processing agent for aromatic polyamide synthetic fibers that is blended in a specific composition ratio to be used when processing aromatic polyamide fibers after the drawing process. Aromatic polyamide synthetic fibers have excellent heat resistance and flame resistance, and have recently been used as flame-retardant fibers. However, unlike polyester fibers or aliphatic polyamide fibers, aromatic polyamide-based synthetic fibers have a very high melting point, and therefore cannot be spun using normal melt spinning methods. Therefore, a wet method or a dry method is generally employed as a silk spinning method, but since the wet method uses a coagulation bath of calcium chloride, calcium chloride remains in the polymer. In both wet and dry methods, lime is added to neutralize the hydrochloric acid produced by the reaction between acid chloride and amine, resulting in the production of calcium chloride.
Furthermore, calcium chloride is often actively added to the polymer dope in order to stabilize the polymer solution. Therefore, in any method, washing with water is usually carried out to remove calcium chloride present in the polymer after the thread spinning process. It is nearly impossible to eliminate all of the calcium chloride remaining in the silk spinning process, and some calcium ions inevitably remain after washing with water, but these residual calcium ions have a major negative impact on the oil treatment process. For example, anionic activators, especially sulfonate or phosphate compounds commonly used as antistatic agents, undergo an ion exchange reaction with calcium ions and turn into water-insoluble calcium salts, making it impossible to obtain the original antistatic performance. In order to obtain a satisfactory antistatic effect, extra oil must be applied. Furthermore, this type of exchange reaction with calcium ions occurs even in an oil-based bath, so what should normally be a water-soluble and transparent aqueous solution becomes cloudy due to the exchange with calcium ions, and furthermore. As the reaction progresses, scum-like substances are generated, which is a major negative factor in stabilizing the silk spinning process. Further, the precipitated scum adheres to the fibers and becomes foreign matter and adheres to rollers and the like in the secondary processing process, particularly the spinning process, causing roller wrapping. Therefore, as an anionic activator, it is desirable to use an oil composition that does not readily form calcium salts and does not form a scum. Furthermore, as is well known, it is extremely difficult to impart antistatic properties to aromatic polyamide fibers compared to polyester fibers, etc., and it is difficult to impart antistatic properties to aromatic polyamide fibers during the secondary processing process using only nonionic activators. For example, it is difficult to provide the necessary antistatic properties in the spinning process. On the other hand, cationic activators cannot be used because they cause needle rust during the spinning process.
Therefore, an anionic activator must be used, but since anionic activators react with calcium ions as described above, the range of specific oil agents that can be selected is extremely narrow. In general, alkyl phosphate compounds that have antirust and antistatic properties have been well known for a long time to improve spinnability, but these compounds have a high reactivity with calcium ions and cause precipitation. It has the disadvantage that it is difficult to obtain stable antistatic properties due to the reaction with calcium ions. Furthermore, there are alkyl phosphates having a polyoxyethylene chain introduced therein, which have improved stability of these alkyl phosphates. This has the advantage that it has low reactivity with calcium ions and does not become floc-like even if it reacts with calcium salts. However, for reasons that are not clear, the spinnability in the spinning process is very poor. The problem arises that productivity is significantly reduced due to occurrence of coiler clogging and increase in roller wrapping. This seems to be due to the increased adhesive strength of the polyoxyethylene alkyl phosphate salt itself. As a result of intensive studies to eliminate these drawbacks, the present inventors found that by incorporating specific oil components as shown below, excellent antistatic properties and stability in secondary processing steps, that is, spinning stability. We have succeeded in obtaining a treatment agent for wholly aromatic polyamide fibers with extremely excellent properties. That is, the present invention uses a potassium salt of a polyoxyalkylene-modified alkyl phosphate having an average carbon number of 8 to 14 alkyl groups (polymerization degree of polyoxyalkylene of 2 to 10) of 70 to 90% (by weight) and a liquid at 30°C. The present invention relates to a treatment agent for aromatic polyamide synthetic fibers, characterized in that it contains 30 to 10% by weight of a nonionic surfactant having the following properties. Examples of aromatic polyamide synthetic fibers in the present invention include the following. (1) Condensation polyamide of dicarboxylic acid having an aromatic ring and diamine having an aromatic ring For example, terephthalic acid as a dicarboxylic acid,
It may be a homopolymer consisting of isophthalic acid, a type of dicarboxylic acid using metaphenylene diamine, xylylene diamine, etc. as the diamine, or a type of diamine. Either or both of the dicarboxylic acid component and the diamine component are two types. It may also be a copolymer consisting of the above compounds. Typical examples include polymethaphenylene isophthalamide, polymethaxylene diamine terephthalamide, and copolymers of metaphenylene diamine, isophthalic acid, and terephthalic acid. (2) Polyamide condensed with aminocarboxylic acid having an aromatic ring For example, as the aminocarboxylic acid, it may be a homopolymer consisting of only one type using para-aminobenzoic acid, methyl para-aminobenzoate, etc. It may also be a copolymer of aminocarboxylic acids. (3) A typical polyamide obtained by copolymerizing the above (1) and (2) may be, for example, a polyamide obtained by co-condensing the three components of metaphenylene diamine, isophthalic acid, and para-aminobenzoic acid. Further, the potassium salt of polyoxyalkylene-modified alkyl phosphate ester used in the present invention has an alkyl group having an average carbon number of 8 to 14, and the degree of polymerization of the polyoxyalkylene used is in the range of 2 to 10. Examples of the polyoxyalkylene group include a polyoxyethylene group obtained by polymerizing ethylene oxide or propylene oxide, and a copolymerized polyoxyalkylene group obtained by copolymerizing ethylene oxide and propylene oxide. These compounds are usually obtained by known methods. That is, a polyoxyalkylene-modified alkyl phosphate ester can be obtained by adding ethylene oxide, propylene oxide, or both ethylene oxide and propylene oxide to a higher alcohol, and reacting a polyoxyalkylene compound having a terminal hydroxyl group with phosphoric anhydride. The potassium salt is especially good. To give a specific example, (( ) is the number of moles of polyoxyalkylene group,
POE stands for polyoxyethylene and POP stands for polyoxypropylene. ) POE(1) octyl phosphate, POE(3) decyl phosphate, POE(5)
Potassium salts such as lauryl phosphate, POP(3) octyl phosphate, decyl phosphate with POP/POE=1/3, and lauryl phosphate with POP/POE=3/7 are used. Further, potassium salts such as POP(1) octyl phosphate, POP(5) decyl phosphate, POP(8) lauryl phosphate, etc. can be used. Potassium salts of polyoxyalkylene-modified alkyl phosphate esters as described above have very low reactivity with calcium ions compared to potassium salts of alkyl phosphates, and the longer the polyoxyalkylene chain is, the more reactive it is. Although it is small, if the potassium salt of the phosphate is 100%, the spinnability decreases, there is a lot of winding in the carding process and the drawing process in the spinning process, and the coiler gets clogged frequently, making it impossible to spin smoothly. The reason for this is not clear, but it may be because the oil itself has a high viscosity and adhesive strength. Further, the alkyl group of the potassium salt of polyoxyalkylene-modified alkyl phosphate ester preferably has an average carbon number of 8 to 14. Particularly preferred are 10 to 12. When the average number of carbon atoms exceeds 14, i.e. cetyl group with 16 carbon atoms, stearyl group or oleyl group with 18 carbon atoms, the viscosity or stickiness of the potassium salt of the corresponding phosphate increases, which may cause problems during the spinning process. There is a tendency for coiler clogging to increase due to poor stability. Furthermore, an alkyl group having an average carbon number of less than 8 cannot be used because the hygroscopicity of the potassium salt of the corresponding phosphate itself increases, the antistatic property decreases, and coiler clogging increases. On the other hand, it was found that it was difficult to satisfactorily stabilize the spinning process using only the potassium salt of a polyoxyalkylene-modified alkyl phosphate ester. In order to maintain the antistatic properties of polyamide synthetic fibers, reduce coiling during the spinning process, and significantly reduce coiler clogging, a specific nonionic surfactant must be added at a concentration of 30 to 10%.
It has been found that the object of the present invention can be achieved by blending in a weight percent. The nonionic surfactant used in combination here is a nonionic surfactant that has a polyoxyethylene chain and is liquid at 30°C. Examples include polyoxyalkylenealkylphenyl ethers, polyoxyalkylene ethers, polyoxyalkylene esters, polyoxyalkylenealkylamines, and the like. If a nonionic surfactant that remains solid at temperatures above 30°C is used in combination with a potassium salt of a polyoxyalkylene-modified alkyl phosphate ester, coiler clogging will occur and spinning performance will be reduced. Therefore, as the nonionic surfactant used in the present invention, a surfactant to which a relatively low number of moles of polyoxyethylene is added is preferably used. The blending amount of these nonionic surfactants is 10~
30% is appropriate. If it is less than 10%, spinnability will decrease, and if it exceeds 30%, it will be 100% potassium salt of polyoxyalkylene-modified alkyl phosphate ester.
Even when compared to a treatment agent consisting of the above, spinnability deteriorates and coiler clogging occurs. 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. It is preferable that the amount of the treatment agent adhered to the fiber is usually 0.1 to 0.6%. As a result, stable spinnability was obtained, and the effect of imparting antistatic properties was maintained even after heat treatment, with almost no coloration observed. The present invention will be specifically explained below with reference to Examples, in which all "%" means "% by weight" and "parts" represent parts by weight. The evaluation methods were as follows: (1) White turbidity of treatment solution The aqueous solution in the treatment tank for treating tow was sampled every hour, and the turbidity and presence or absence of precipitated scum were qualitatively determined. (2) Card characteristics in the spinning process 300 gel/300 gelatin at 25℃ and 65% relative humidity
Yard, 12rpm, if there are no problems, including coiler tube clogging when taking out the card and sliver dripping between the calender roll and coiler, mark as ○, and if spinning performance is particularly poor and smooth spinning cannot be achieved, mark as ×, intermediate Those with △ were judged as △. In addition, as for the characteristics in the drawing process, 300 gels/yard were passed through the drawing machine three times at a spinning speed of 180 m/min under the conditions of 25°C and 65% relative humidity, and the drawing roller was not clogged during unwinding. Observe the wrapping around the drawing roller, and mark the one that is good overall as 〇.
Those that were particularly poor and could not pass through the drawing process smoothly were rated as x, and those in the middle were rated as △. Examples 1 to 4, Comparative Examples 1 to 3 A polymetaphenylene isophthalamide dope obtained by polymerizing m-phenylene diamine and isophthalic acid chloride was extruded into an aqueous calcium chloride solution and solidified to form a 128,000 denier tow. year,
After washing it with water, it was stretched 3.2 times in boiling water, then dried, and heat treated at 340°C. Then, a 2% aqueous solution of the treatment agent with the compounding ratio shown in Table 1 was made into a tow before crimping at room temperature. After adhesion, drying and crimping, the tow was cut to obtain short fibers of 2 denier and 51 m/m. The amount of treatment liquid attached to the fibers is
It was 0.25%. Each of the obtained raw cottons was passed through a spinning process and the quality of spinnability was compared and evaluated. The results are shown in Table-1.

【table】

[Table] Examples 5 to 7, Comparative Examples 4 to 6 An aromatic polyamide dope obtained by polymerizing m-phenylenediamine and isophthalic acid chloride was extruded into a calcium chloride aqueous solution and coagulated, resulting in a 128,000 denier The tow was washed with water, stretched 3.2 times in boiling water, then dried, and heated at 340°C.
Then, 2% of the treatment agent shown in Table 2 was applied.
It was applied as an aqueous solution to the tow at room temperature before crimping, dried and crimped, and the tow was cut to obtain short fibers of 2 denyl and 51 m/m. The amount of treatment agent attached to the fibers was 0.20% in all cases. Each of the obtained raw cottons was passed through a spinning process and the quality of spinnability was compared and evaluated. The results are shown in Table-2.

【table】

【table】

【table】

Claims (1)

[Claims] 1 Potassium salt of polyoxyalkylene-modified alkyl phosphate having an alkyl group having an average carbon number of 8 to 14 (degree of polymerization of polyoxyalkylene n =
2-10) A processing agent for aromatic polyamide synthetic fibers, comprising 70-90% by weight and 30-10% by weight of a nonionic surfactant that is liquid at 30°C.