JPH059526B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an elastic yarn, and an object thereof is to provide an elastic yarn with less permanent deformation and excellent elastic performance. Conventionally, rubber, polyurethane, etc. have been used as elastic threads, but although these exhibit excellent properties in terms of elastic recovery, they have problems such as excessive elongation, heat resistance, weather resistance, etc. On the other hand, polyether polyester type elastomers have recently begun to be used as resins. When this polymer is made into thread, although it is not as good as polyurethane in terms of elongation recovery, it exhibits relatively good recovery in the low elongation range, and also has the advantage of being melt-spun. Unlike polyurethane, which uses hydrogen bonds, this polyether polyester type elastic yarn uses the cohesive force of the hard segment crystals to hold molecules together, so the bonding force is not necessarily sufficient, and it is affected by external forces received during the spinning process. The disadvantage is that the elastic performance is easily affected. In order to eliminate this problem, the present inventors have arrived at the present invention as a result of intensive studies. Aromatic polyester is used as a hard segment,
An elastic thread made of an elastic polyether ester block copolymer having polyether as a soft segment, which contains (a) 0.05 to 5 parts by weight of a crystal nucleating agent and (b) based on 100 parts by weight of the elastic copolymer. At least one kind of inorganic fine powder selected from the group of China clay, kaolin, calcium carbonate, calcium phosphate, and titanium oxide, which does not affect crystallinity, 0.01~
This is a polyetherester elastic yarn characterized by containing 15 parts by weight. In the present invention, the "aromatic polyester" constituting the hard segment of the polyether ester block copolymer refers to a polyester containing aromatic dicarboxylic acid as the main acid component and aliphatic glycol as the main glycol component. Here, "main" is usually 70 mol% or more, preferably 80 mol%
Refers to the above. Examples of "aromatic dicarboxylic acids" include terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, diphenoxyethane dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl ketone dicarboxylic acid, diphenyl sulfone dicarboxylic acid, etc. For example, it is preferable that 80 mol% or more of the total acid components consist of the same acid. Examples of the "aliphatic glycol" include ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, etc., and it is preferable that 80 mol% or more of the total glycol component consists of the same glycol. Among these, ethylene glycol, tetramethylene glycol, and hexamethylene glycol are preferred, and tetramethylene glycol is particularly preferred. In the present invention, the "polyether" constituting the soft segment of the polyether ester block copolymer means a polymer of the aliphatic glycols listed above, specifically polyethylene glycol, polypropylene glycol, polytetramethylene glycol. , or copolymers thereof. The molecular weight of the polyether is preferably 500 to 6,000, particularly preferably 800 to 3,000. The hard segment/soft segment ratio of the polyether ester block copolymer can be arbitrarily changed depending on the required performance, but is usually 10/90 to 90/10, preferably 15/85 to 15/85 on a weight basis.
50/50 is used. The degree of polymerization of the polyether ester block copolymer can be arbitrarily set depending on the required performance, but usually the orthochlorophenol solution is
A reduced specific viscosity measured at °C of around 1.0 to 2.5 is used. The polyether ester block copolymer is
It can be produced in accordance with a common method for producing copolyester. Specifically, an aromatic dicarboxylic acid and/or its alkyl ester, an aliphatic glycol, and a polyether are placed in a reactor, and a direct esterification or transesterification reaction is carried out in the presence or absence of a catalyst, followed by a high vacuum reaction. This method involves carrying out a polycondensation reaction to increase the degree of polymerization to a desired degree. In some cases, polyether may be added at the initial stage of polymerization to cause copolymerization, and the timing of addition is arbitrary. The polyether ester block copolymer contains, like ordinary polyester, a quenching agent, a pigment such as carbon black, an antioxidant such as a hindered phenol compound or a hindered amine compound, and an ultraviolet absorber such as a benzophenone compound. There is no problem even if it contains benzotriazole compounds, salicylate compounds, etc. Examples of the crystal nucleating agent (a) used in the present invention include ordinary organic nucleating agents and inorganic nucleating agents. Specifically, sodium benzoate, potassium benzoate, sodium stearate, calcium stearate, barium stearate, zinc stearate, sodium palmitate, sodium myristate, sodium montanate, sodium acetylacetone,
Examples include talc, feldspar, etc., but are not limited to these. Preferred crystal nucleating agents vary depending on the aromatic polyester constituting the hard segment. For example, when the aromatic polyester is polyethylene terephthalate, sodium montanate, and when the aromatic polyester is polybutylene terephthalate, talc, metal stearate, etc. are relatively preferably used. The average particle size is preferably 10μ or less since it is used as thread. The amount of the crystal nucleating agent may be sufficient as long as it provides a crystallization promoting effect. Specifically, it is usually used in an amount of 0.05 to 5.0 parts by weight, preferably 0.1 to 3 parts by weight, per 100 parts by weight of the polyether ester block copolymer. Examples of (b) inorganic fine powder that does not affect crystallinity used in the present invention include chiaina clay, kaolin,
At least one material selected from the group of calcium carbonate, calcium phosphate, and titanium oxide having a lubricant effect is used. The amount of these inorganic fine powders is based on 100 parts by weight of the polyether ester block copolymer elastomer.
The amount is 0.01 to 15 parts by weight, preferably 0.5 to 10 parts by weight. Further, the particle size of the inorganic fine powder may be any size as long as it does not cause trouble in a normal silk spinning process, but it is preferably about 0.1 to 10 μm. If the particle size is too large, the pack pressure increases during spinning and thread breakage is likely to occur.On the other hand, if the particle size is too small, the expected effect will not be obtained unless the amount of inorganic fine powder is increased, but it will stabilize the process. It is possible to arbitrarily choose whether to improve the physical properties or improve the physical properties. Therefore, the particle size and amount of the inorganic fine powder can be selected depending on the intended use and denier of the elastic yarn. The polyether ester block copolymer composition described above can be melt-spun very easily without any special means, so it can be spun according to the melt-spinning method for general thermoplastic polymers.
That is, unlike polyurethane elastic yarns, the denier of yarns and single yarns can be set arbitrarily, similar to ordinary polyester fibers. The yarn obtained by melt-spinning the above block copolymer composition has sufficient elasticity as it is, but it may be further subjected to stretching and/or heat treatment depending on the purpose of use of the elastic yarn. Any of elongation heat treatment, constant length heat treatment, and relaxation heat treatment may be used. The effect of the crystal nucleating agent of the present invention is to improve the cohesive force of the crystals by increasing the crystallinity of the hard segments of the polyether ester block copolymer, and thereby to control the expression of entropic elasticity of the soft segments. It is something. The effect of the other inorganic fine powder is not clearly known, but the inventor's understanding is as follows. When a polyether ester block copolymer oriented with inorganic fine powder is elongated, under ideal conditions, no voids are formed at the interface between the inorganic fine powder and the polyether ester block copolymer; In this case, the adhesion between the two is insufficient and voids are formed during elongation, and it is thought that the voids become larger especially in the case of slippery inorganic fine powders. These voids generally have the opposite effect to that of fillers such as carbon black in rubber, i.e.
It is thought to have the effect of reducing the initial Young's modulus. In other words, it is thought that it is easier to pull when stretched, exhibits a phenomenon that is generally referred to as an inverse correlation between elastic recovery and elastic modulus, and improves elasticity.
Therefore, the combination of polyether ester block copolymer and inorganic fine powder is important, but in general it can be said that inorganic fine powder that has a slippery effect is effective. Increase the crystallinity of the above hard segments,
The effect of the crystal nucleating agent, which increases the cohesive force of the crystal, increases the instantaneous elastic recovery, and reduces the permanent strain, and the effect of amorphizing the soft segment due to the void effect of the inorganic fine powder as a filler may be contradictory. They are not the same thing. In other words, the two effects appear to be additive, although not in a strict sense. Furthermore, although the elastic yarn according to the present invention is not as good as polyurethane elastic yarn, it exhibits relatively good elongation recovery under low elongation of 100% or less. Polyurethane elastic yarns have the disadvantage of being too stretched during post-processing, but in the field of small to medium deformation stretching, the elastic yarns of the present invention have better post-processing properties. In addition, since the frictional resistance is lower than that of conventional products, there is less tension fluctuation due to slipping with guides or catching during post-processing steps. The present invention will be specifically explained below with reference to Examples.
Note that parts in the examples are parts by weight, and the performance of the product yarn was measured by the method shown below. Further, the reduced specific viscosity of the polymer was calculated from the solution viscosity of a 0.8 g/100 ml solution of the polymer in orthochlorophenol at 35°C. Further, each performance of the elastic yarn was measured by the following method. 1 Elongation recovery (1) Instantaneous elongation recovery rate Apply a load corresponding to 50% or 100% elongation to a 10 cm sample, quickly elongate it by 50% or 100%, remove the load after 5 seconds, and quickly increase the sample length to 1 cm. Read and calculate using the following formula. Instantaneous elongation recovery rate = 10-(l-10)/10×100(%) (2) Elongation modulus JIS L 1073 (1977) Synthetic fiber yarn test method Elongation elastic modulus B method 10
%, elongation modulus at 50% or 100% elongation. (3) Long-term elongation recovery rate A load equivalent to 100% elongation is applied to a 10 cm long sample and left for 4 hours (sample length at this time is 1 cm), then the load is removed and the recovery rate after 4 hours of elongation is Measure the sample length l'cm and calculate it using the following formula. Long-term elongation recovery rate = l-l'/10 x 100 (%) 2 Permanent set When measuring long-term elongation recovery rate, permanent set = l'-10/10 x 100 (%) 3 Crystallinity 1st The degree of crystallinity of the aromatic polyester portion of the elastomer composition obtained under the conditions shown in Table 2 was calculated from X-rays. Examples 1 to 5, Comparative Examples 1 to 4 167.3 parts of dimethyl terephthalate, 105 parts of tetramethylene glycol, 325 parts of polytetramethylene glycol with a number average molecular weight of 2000, 0.35 parts of tetrabutyl titanate, and 0.5 parts of pentaerythritol were charged into a reactor. The transesterification reaction was carried out at a temperature of 170°C. When 70% of the theoretical amount of methanol had distilled out, predetermined amounts of the crystal nucleating agent and inorganic fine powder shown in Table 1 were added. (It was actually added as a 20% tetramethylene glycol slurry.) Then,
Raise the temperature of the system and begin to reduce the pressure by 30mm over approximately 30 minutes.
Hg, then increased to 3mmHg over 30 minutes, then 1mm
The reaction was carried out for 240 minutes at an internal temperature of 245°C under a Hg vacuum.
The performance of the obtained polymer is listed in Table 1. After drying the polymer thus obtained, it was melted at 270°C and rolled up at a discharge rate of 20 g/min and a spinning speed of 1100 m/min. Table 1 shows the physical properties of the yarns, including those that were partially post-treated.

【table】

[Table] Examples 6, 7, Comparative Examples 5 to 8 Polyethylene glycol with a number average molecular weight of 3000 instead of polytetramethylene glycol in Example 1
325 parts, and the crystal nucleating agent and inorganic fine powder were used in the second
Polymers as shown in the table were prepared and spun. Similarly, 101.7 parts of ethylene glycol was used instead of tetramethylene glycol, and a crystal nucleating agent,
For the inorganic fine powder, the polymers shown in Table 2 were produced and spun into yarn. The above fiber properties are shown in Table 2.

【table】

[Table] Kaolin instead of 10.0 parts of titanium oxide in Example 1
A polymer was produced in the same manner as in Example 1, except that 8.0 parts (Example 8) or 10.0 parts of calcium phosphate (Example 9) was used, and yarn was spun. The results are shown in Table 3.

【table】

Claims (1)

[Claims] 1. An elastic thread made of a polyether ester block copolymer elastic body having aromatic polyester as a hard segment and polyether as a soft segment, wherein (a) a crystal nucleating agent is added to 100 parts by weight of the copolymer elastomer. 0.05 to 5 parts by weight and (b) at least one inorganic fine powder selected from the group of china clay, kaolin, calcium carbonate, calcium phosphate, and titanium oxide that does not affect crystallinity.
A polyetherester elastic yarn characterized by containing 0.01 to 15 parts by weight.