JP2018100392A - Copolymerization polyester resin composition and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a copolymerization polyester resin composition, which has high moisture absorption property, can be spinned solely or in combination, and can be used as a comfortable base material such as underwear, sport wear, and backing fabric, as a woven fabric formed from a hygroscopic fiber.SOLUTION: A copolymerization polyester resin composition is obtained by copolymerization of 10-50 wt.% of polyethylene glycol having a number average molecular weight of 5000-20000 and 80-800 mol/ton of a structure represented by general formula (1), and has a main repeating unit of ethylene terephthalate, where a dispersion diameter of an island phase in a phase separation structure is 1-50 nm.SELECTED DRAWING: None

Description

  The present invention relates to a copolyester resin composition having hygroscopicity and a method for producing the same.

  Polyesters are widely used in applications such as fibers, films, and molded articles because they are excellent in strength, thermal stability, chemical resistance, and the like. However, since polyethylene terephthalate is hydrophobic in nature, it is extremely poor in hygroscopicity, and when used as clothing, it may cause “swelling” at high humidity or static electricity at low humidity in winter. It is not a preferable material for comfort. In addition, when used as a resin or a film, it may become charged due to its low hygroscopicity.

  In order to eliminate this defect, a compound having a hygroscopic property such as copolymerization of a diol having an oxyalkylene glycol in the side chain (Patent Document 1) and copolymerization of a sulfonic acid metal salt-containing dicarboxylic acid (Patent Document 2) is applied to polyester. Copolymerization methods have been proposed. However, the entire polymer is modified by copolymerizing the moisture-absorbing component, and the inherent advantage of polyester, which is excellent mechanical properties, is lost.

  Also known is a method of imparting hygroscopicity by graft-polymerizing acrylic acid or methacrylic acid to a polyester fiber, and further substituting those carboxyl groups with an alkali metal after graft polymerization (Patent Document 3). However, it has not been put into practical use because it has problems of lightness reduction, occurrence of slimming due to adhesion of moisture-absorbing components to the composition or fiber surface layer, and deterioration of strength over time.

  In the method of imparting hygroscopicity in the post-processing stage, there are various problems in dyeing or in the properties of the obtained fabric. Therefore, in order to provide hygroscopicity in the stage of manufacturing the fiber and to solve the problem, high hygroscopicity is required. A core-sheath type composite fiber is proposed in which a hygroscopic resin having a property is used as a core and covered with a polyester sheath (Patent Documents 4 to 8). However, in these core-sheath type composite fibers, the hygroscopic resin in the core part contains water and swells greatly during hot water treatment such as scouring and dyeing, so that cracks (sheath cracks) occur on the fiber surface, and the hygroscopic resin There were drawbacks in that the quality of the fabric was lowered, such as outflow to the outside and marked deterioration of dyeing fastness.

  In order to suppress this sheath cracking, a method has been proposed in which a hollow portion adjacent to a hygroscopic core component is provided in advance from the melt spinning stage (Patent Documents 10 and 11). However, when the fiber is formed into a shape having a hollow part, when the fiber is twisted or false twisted, the hollow part is crushed in this step, and the above-mentioned case is caused by the subsequent hot water treatment. In the same manner as the above, there is a defect that the hygroscopic polymer swells and a sheath crack occurs. Furthermore, since it is a composite fiber, it was difficult to reduce the fineness.

  In order to solve these problems, Patent Document 12 discloses a copolyester that exhibits high moisture absorption performance by a polyethylene glycol copolyester having a special amorphous structure.

Japanese Patent Laid-Open No. 48-8270 JP-A-2-26985 Japanese Patent Publication No.59-17224 JP-A-2-99612 JP-A-4-361616 JP-A-4-341617 JP-A-8-198954 Japanese Patent Laid-Open No. 9-132871 JP 2001-172374 A JP-A-9-111579 JP 52-55721 A WO2014 / 050652

When the copolyester disclosed in Patent Document 12 is used, it is possible to obtain a fiber that can be spun independently and has good hygroscopicity. However, since the obtained copolyester has low heat resistance, there is a problem that thermal decomposition occurs due to heating and melting in the spinning and melting step, and the strength of the obtained fiber is lowered. In addition, since the polyethylene glycol component in the obtained copolyester is oxidatively decomposed by oxygen in the air, the hygroscopic performance decreases with time with respect to the added amount of polyethylene glycol, and it is continuously increased by a dryer or iron. When heated to a high temperature, the fiber itself may oxidize and deteriorate.
An object of the present invention is to provide a copolymerized polyester resin composition having high moisture absorption characteristics and good spinnability while overcoming the problems of the prior art and maintaining the excellent properties inherent in polyester. .

The above-mentioned problem is a copolymerized polyester obtained by copolymerizing polyethylene glycol having a number average molecular weight of 5000 to 20000% by weight with 10 to 50% by weight, and a structure represented by the following general formula (1), and having a phase separation structure of 80 to 800 mol / ton. The dispersion diameter of the island phase in can be achieved by a copolymer polyester resin composition characterized by being 1 to 50 nm.

  The copolymer polyester resin composition of the present invention is highly hygroscopic and can be spun alone or in combination, and used as a comfortable material for underwear, sportswear, lining, etc. as a woven or knitted fabric made of hygroscopic fibers. Can do.

  The present invention relates to a copolymerized polyester resin composition obtained by copolymerizing 10 to 50% by weight of polyethylene glycol having a number average molecular weight of 5000 to 20000 and 80 to 800 mol / ton of a structure represented by the following general formula (1). .

In the present invention, the polyester is a polyester comprising a dicarboxylic acid and an ester-forming derivative thereof, a diol and an ester-forming derivative thereof.
Specific examples of such polyester include polyethylene terephthalate, polytrimethylene terephthalate, polytetramethylene terephthalate, polycyclohexylene dimethylene terephthalate, polyethylene-2,6-naphthalenedicarboxylate, polyethylene-1,2- And bis (2-chlorophenoxy) ethane-4,4′-dicarboxylate. In the present invention, polyethylene terephthalate is particularly preferable.

  These polyesters are copolymerized with dicarboxylic acids such as isophthalic acid, naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, cyclohexanedicarboxylic acid, 5-sulfoisophthalic acid, and ester-forming derivatives thereof as dicarboxylic acid components. May be. The amount of the copolymerized dicarboxylic acid component in the total dicarboxylic acid component is preferably 20 mol% or less, more preferably 10 mol% or less.

  These polyesters may be copolymerized with a dioxy compound such as hexamethylene glycol, neopentyl glycol, polypropylene glycol, cyclohexane dimethanol, or an ester-forming derivative thereof as a diol component. Preferably, ethylene glycol in the total diol component is 80 mol% or more. As diol components other than ethylene glycol, cyclohexanedimethanol, butanediol, neopentyl glycol, diethylene glycol and the like can be copolymerized within a range not impairing the effects of the present invention.

  The polyethylene glycol copolymerized with the copolymerized polyester of the present invention has a number average molecular weight of 5,000 to 20,000, and is characterized by being copolymerized by 10 to 45% by weight with respect to the copolymerized polyester obtained. Here, a specific method for measuring the number average molecular weight and the copolymerization amount of polyethylene glycol in the copolymerized polyester resin composition will be described later. After the copolymerized polyester is hydrolyzed with an alkaline aqueous solution, a gel permeation chromatograph (GPC) is used. ).

  By setting the polyethylene glycol copolymerized in the copolymerized polyester resin composition to a specific number average molecular weight, the hygroscopic property is extremely increased and the processability is improved. Specifically, when the number average molecular weight of polyethylene glycol copolymerized in the copolymerized polyester composition is 5000 or more, the hygroscopic performance is extremely increased. The reason for this is not clear, but if the number average molecular weight is 5000 or more, the polyethylene glycol and the polyester in the copolymerized polyester of the present invention form a unique structure, and therefore the hygroscopicity is extremely high. ing.

  When the number average molecular weight of the polyethylene glycol copolymerized in the copolymerized polyester resin composition exceeds 20000, the reactivity with polyethylene terephthalate is lowered, so that the yarn-making property is inferior, and the polyethylene glycol is dissolved in hot water. Arise. The number average molecular weight of the polyethylene glycol copolymerized in the copolymerized polyester resin composition is more preferably 10,000 or less from the viewpoint of moldability, particularly yarn production.

  The copolymerization amount of polyethylene glycol copolymerized with the copolymerized polyester resin composition of the present invention is 10 to 50% by weight. If the copolymerization amount of polyethylene glycol is less than 10% by weight, the resulting copolymer polyester does not have the hygroscopicity, and has a hygroscopicity equivalent to that of the polyester not copolymerized with polyethylene glycol. Moreover, the addition amount of polyethylene glycol needs to be 50 weight% or less from a viewpoint of heat resistance, melt moldability, for example, spinnability. This is because when the amount exceeds 50% by weight, the obtained copolymer polyester cannot withstand use in a high temperature range, or the mechanical strength of the molded product is lowered. The copolymerization amount of polyethylene glycol is preferably 10 to 45% by weight, more preferably 15 to 45% by weight, still more preferably 15 to 40, and still more preferably 15 to 35% by weight.

  The copolymer polyester resin composition of the present invention needs to be copolymerized with a structure represented by the following general formula (1) at 80 to 800 mol / ton.

  By co-polymerizing the structure represented by the general formula (1) of the present invention at 80 to 800 mol / ton, both the moisture absorption property and the spinnability of the copolymerized polyester resin composition can be achieved.

  When a high molecular weight polyethylene glycol is copolymerized, a polyethylene glycol-polyester copolymer obtained by reacting a high molecular weight polyethylene glycol and a polyester is produced. However, when the molecular weight of polyethylene glycol is high, the number of moles of polyethylene glycol is small, so there is a homopolyester polymer in addition to the polyethylene glycol-polyester copolymer, and these two phases separate to form a sea-island structure. In this case, the interfacial tension between the island phase and the sea phase increases, and the phenomenon that the polymer swells just below the die during spinning, the so-called ballast effect, increases, and the spinnability becomes unstable. In addition, the obtained fiber is likely to cause thickness spots. These phenomena are prominent when producing fine fibers and induce thread breakage.

  Here, when the structure represented by the general formula (1) is included in the sea component, the structure becomes a dispersant, and the interfacial tension at the sea-island interface is lowered, so that it is difficult to produce a ballast effect immediately below the base. As a result, the spinnability is improved, the unevenness in the thickness of the obtained fiber is eliminated, and the spinnability is improved even with a fine fiber.

The copolymer polyester resin composition of the present invention needs to have a structure represented by the general formula (1) of 80 to 800 mol / ton.
If it is less than 80 mol / ton, the effect as a dispersing agent will be small, and spinnability will become unstable. On the other hand, when it exceeds 800 mol / ton, the heat resistance of the polymer is lowered, the color tone of the polymer is deteriorated, or thermal decomposition occurs due to heat at the time of spinning and melting such as a spinning process, and mechanical properties, particularly strength in the fiber is lowered. Preferably it is 200-600 mol / ton.

The copolymer polyester resin composition of the present invention is characterized in that the island phase dispersion diameter in the phase separation structure is 1 to 50 nm.
Here, the phase separation structure can be observed with an electron microscope. Specifically, after cutting a pellet of the copolymer polyester resin composition to obtain a cross-sectional slice, it can be stained with osmium and observed with a transmission electron microscope (TEM). ) Is a sea component, and a sea-island structure in which a component (gray portion) dispersed in a substantially circular shape (including a perfect circle) is an island component can be observed. Here, the white part is a component mainly composed of polyester, and the gray part is a component mainly composed of polyethylene glycol.

The dispersion diameter of the island component can be obtained from the diameter converted from the area of the island component assuming that the island component is a circle.
When the dispersion diameter of the island phase in the dispersion structure exceeds 50 nm, the island polymer becomes a defect, resulting in a decrease in spinnability and fiber strength. In particular, in spinning, the spinnability and fiber strength are reduced. In addition, since many hindered phenolic antioxidants are present at the interface between the sea phase and the island phase, if the dispersion diameter of the island phase exceeds 50 nm, the performance of the antioxidant cannot be exhibited sufficiently.
When the dispersion diameter of the island phase is smaller than 1 nm, the moisture absorption performance is remarkably lowered. This is because it is known that the moisture absorption performance is exhibited in the island phase, and in order to exhibit sufficient moisture absorption performance, the island phase has a certain size and requires a space containing water. The dispersion diameter of the island phase of the dispersion structure is preferably 2 to 10 nm.

Next, the manufacturing method of the copolyester resin composition of this invention is demonstrated.
The present invention relates to a method for producing a copolyester produced by polycondensation reaction of an aromatic dicarboxylic acid or an ester-forming derivative thereof, a diol or an ester-forming derivative thereof, and polyethylene glycol.

  Specific examples of the aromatic dicarboxylic acid or an ester-forming derivative thereof used in the method for producing a copolyester of the present invention include terephthalic acid, naphthalenedicarboxylic acid, and ester-forming derivatives thereof. Among them, terephthalic acid and its ester-forming derivatives are preferable because they are inexpensive and effective in terms of economy, and the processability of the obtained copolymer polyester, in particular, the spinnability is good.

  Specific examples of diols or ester-forming derivatives thereof used in the method for producing a copolyester of the present invention include ethylene glycol, 1,3-propanediol, 1,4-butanediol, cyclohexanedimethanol and ester formation thereof. Sex derivatives.

  Specific examples of polyesters comprising dicarboxylic acids and their ester-forming derivatives and diols and their ester-forming derivatives include, for example, polyethylene terephthalate, polytrimethylene terephthalate, polytetramethylene terephthalate, polycyclohexylene dimethylene terephthalate, and polyethylene. -2,6-naphthalene dicarboxylate and the like. In the present invention, among these, polyethylene terephthalate is preferable from the viewpoints of physical properties and economy.

  The polyethylene glycol added by the method for producing a copolyester of the present invention has a number average molecular weight of 6000 to 20000, and is characterized by being added by 10 to 50% by weight with respect to the copolyester obtained. About the measuring method of the number average molecular weight of the polyethylene glycol to add, it measures by the terminal group determination method.

  When the polyethylene glycol to be added has a specific number average molecular weight, the hygroscopic property is increased and the processability is improved. Specifically, when the number average molecular weight of the added polyethylene glycol is 6000 or more, the hygroscopic performance becomes extremely large. The reason for this is not clear, but when the number average molecular weight is 6000 or more, polyethylene glycol and polyethylene terephthalate in the copolymerized polyester obtained by the production method of the present invention form a unique structure. We think that the hygroscopicity becomes extremely high.

  When the number average molecular weight of polyethylene glycol exceeds 20000, the reactivity with polyethylene terephthalate is lowered, so that the spinning property is inferior, and the problem that polyethylene glycol dissolves with hot water arises. The number average molecular weight of the polyethylene glycol to be added is more preferably 10,000 or less from the viewpoint of moldability, in particular, yarn production.

  Specifically, for example, PEG-6000S, PEG-6000P, PEG-10000, PEG-13000, PEG-20000, PEG-20000P manufactured by Sanyo Chemical Industries, Ltd. can be used as the polyethylene glycol of the present invention. It is not limited.

  The amount of polyethylene glycol added in the method for producing a copolyester of the present invention is 10 to 50% by weight. If the addition amount of polyethylene glycol is less than 10% by weight, the resulting copolymer polyester cannot have the hygroscopicity, and the hygroscopicity is equivalent to that of the polyester not copolymerized with polyethylene glycol. From the viewpoint of heat resistance and melt moldability, for example, spinnability, the amount of polyethylene glycol added needs to be 50% by weight or less, preferably 45% by weight or less. This is because when the amount exceeds 50% by weight, the obtained copolymer polyester cannot withstand use in a high temperature range, or the mechanical strength of the molded product is lowered. In producing the fiber, in order to use it as a single yarn, the amount of polyethylene glycol added is preferably 25% by weight or less. When the addition amount of polyethylene glycol is 25% by weight or less, the spinnability is improved, the spinning speed can be increased, the productivity is improved, and a fine fiber can be obtained. More preferably, it is 20 weight% or less.

  On the other hand, when the addition amount of polyethylene glycol is 25% by weight or more, extremely high moisture absorption performance can be obtained, which is preferable because it can be used as a moisture absorption component in the composite fiber. In order to use as a hygroscopic component in the composite fiber, the ratio of the hygroscopic component in the composite fiber can be lowered when the addition amount of polyethylene glycol is 30% by weight or more, and the mechanical properties of the obtained fiber are improved. preferable. Examples of the form of the composite fiber include a core-sheath type composite fiber, a core-sheath type composite hollow fiber, a sea-island type composite fiber, a laminated type composite fiber, a blend fiber, and the like. It can be used as a component.

In the core-sheath type composite fiber and the core-sheath type composite hollow fiber, the copolymerized polyester of the present invention can be used as the core component or the sheath component.
In the sea-island type composite fiber, the copolymer polyester of the present invention can be used as a sea component or an island component.
Moreover, in the case of the synthetic fiber which mix | blended the copolymer polyester of this invention with the fiber-forming resin, it is preferable that the mixture ratio of copolymer polyester shall be 20 to 80 weight% with respect to the total polymer amount. Preferably it is 30 to 70% by weight. The lower limit of the blending ratio can be set for the purpose of imparting sufficient hygroscopicity, and the upper limit of the blending ratio is set from the viewpoint of preventing the spinnability and fiber properties from decreasing.

  Polyethylene glycol, which is a copolymerization component, has low heat resistance, and polyethylene glycol is thermally decomposed during the polycondensation reaction, resulting in a decrease in molecular weight. When the molecular weight of polyethylene glycol decreases during the polycondensation reaction, the polyethylene glycol unit in the copolymerized polyester becomes shorter, and the polyethylene glycol and polyethylene terephthalate in the copolymerized polyester cannot form a unique structure and are obtained. Further, the moisture absorption performance of the copolyester cannot be exhibited sufficiently. In addition, when the melt residence time becomes long even during spinning melting, the thermal decomposition of polyethylene glycol proceeds and the molecular weight of polyethylene glycol decreases, so the moisture absorption performance of the obtained copolyester decreases.

  The method for producing a copolyester resin composition of the present invention is characterized by adding 10 to 30% by weight of a compound represented by the following general formula (2).

(However, n and m are integers of 2 to 20, and n + m is 4 to 30)
When n + m of the compound represented by the general formula (2) of the present invention is 4 to 30, the dispersion diameter of the island phase of the copolyester obtained is finely dispersed and the spinnability is improved, which is preferable. Furthermore, it is more preferable that n + m is 4 to 10 because melting heat resistance tends to be improved and polymer color tone is also improved.

  The compound represented by the general formula (2) of the present invention is specifically an ethylene oxide adduct of bisphenol-A, such as New Pole BPE-20, New Pole BPE-20 (manufactured by Sanyo Chemical Industries, Ltd.). F), New Pole BPE-20NK, New Pole BPE-20T, New Pole BPE-40, New Pole BPE-60, New Pole BPE-100, New Pole BPE-180, Bisol 30EN manufactured by Toho Chemical Industry Co., Ltd. However, it is not limited to these.

  The addition amount of the general formula (2) of the present invention is preferably 10 to 30% by weight. When the content is 10% by weight or more, the dispersion diameter of the island phase of the copolymerized polyester becomes finer, and the spinnability tends to be improved. In addition, when an antioxidant is added, it is known that the antioxidant is present at the sea-island interface, and since the specific surface area of the island phase increases, the effect of the antioxidant is easily exerted, and the oxidative degradation resistance is improved. It is preferable because it improves. Here, the oxidation degradation resistance evaluation method is specifically described later, but can be evaluated by an oxidation heat generation test. The addition amount of the general formula (2) of the present invention is more preferably 15% or more.

  On the other hand, the thermal properties of the copolymerized polyester resin composition obtained when the amount of the compound having the structure represented by the general formula (2) is 30% by weight or less, particularly, the melting point and the glass transition temperature are increased, and the strength of the fiber is increased. It is preferable because it tends to decrease and improve the heat-resistant temperature. More preferably, it is 20% by weight or less.

  0.1% of the resin composition from which the hindered phenolic antioxidant can be obtained during the period from the start of the pressure reduction in the polycondensation reactor until the copolymerized polyester resin composition reaches the target degree of polymerization. Addition of ˜5.0% by weight makes it possible to produce a copolyester resin composition having very good oxidation resistance and particularly good color tone. When the addition amount is less than 0.1% by weight, the oxidative decomposition resistance becomes insufficient. On the other hand, when the addition amount is more than 5.0% by weight, the color tone is lowered.

  Specific examples of the hindered phenol antioxidant of the present invention include 3,5-di-t-butyl-4-hydroxy-toluene and n-octadecyl-β- (4′-hydroxy-3 ′, 5 ′. -Di-t-butylphenyl) propionate, tetrakis [methylene-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane, 1,3,5-trimethyl-2,4 , 6'-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, calcium (3,5-di-t-butyl-4-hydroxy-benzyl-monoethyl-phosphate), triethylene Glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], penterythrityl-tetrakis [3- (3,5-di-tert-butyl) Ruanilino) -1,3,5-triazine, 3,9-bis [1,1-dimethyl-2- {β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} ethyl] 2 , 4,8,10-tetraoxaspiro [5,5] undecane, bis [3,3-bis (4′-hydroxy-3′-t-butylphenyl) butyric acid] glycol ester, triphenol, 2,2 ′ -Ethylidenebis (4,6-di-t-butylphenol), N, N'-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine, 2,2'-oxamide bis [Ethyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,1,3-tris (3 ′, 5′-di-t-butyl-4′-hydroxybenzyl) − Triazine-2,4,6 (1H, 3H, 5H) -trione, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 3,5- Di-t-butyl-4-hydroxyhydrocinnamic ahydrtriester with-1,3,5-tris (2-hydroxyethyl) -S-triazine-2,4,6 (1H, 3H, 5H), N , N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5- Methylphenyl) propionyloxy] -1,1-dimethylethyl} -2,4,8,10-tetraoxaspiro [5.5] undecane. Among these, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, 1 from the viewpoint of suppressing yellowing of the color tone of the obtained copolymer polyester , 3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5) -Methylphenyl) propionyloxy] -1,1-dimethylethyl} -2,4,8,10-tetraoxaspiro [5.5] undecane having a molecular weight of 500 or more is preferred.

  In the method for producing the copolyester of the present invention, dicarboxylic acid components such as isophthalic acid, naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, cyclohexanedicarboxylic acid, 5-sulfoisophthalic acid and the like and their ester forming properties are used. Derivatives may be copolymerized. The amount of the copolymerized dicarboxylic acid component in the total dicarboxylic acid component is preferably 20 mol% or less, more preferably 10 mol% or less.

  These polyesters may be copolymerized with a dioxy compound such as hexamethylene glycol, neopentyl glycol, polypropylene glycol, cyclohexane dimethanol, or an ester-forming derivative thereof as a diol component. Preferably, ethylene glycol in the total diol component is 80 mol% or more, more preferably 90 mol% or more. As diol components other than ethylene glycol, cyclohexanedimethanol, butanediol, neopentyl glycol, diethylene glycol, polyethylene glycol having a molecular weight of less than 6000, and the like can be copolymerized within a range that does not impair the effects of the present invention.

  In the method for producing a copolyester of the present invention, a pigment such as titanium oxide and carbon black, a surfactant such as an alkylbenzene sulfonate, a conventionally known antioxidant, an anti-coloring agent, and the like within a range not impairing the object of the present invention. Of course, a light-proofing agent, an antistatic agent or the like may be added.

The method for producing the copolyester of the present invention will be described in more detail.
The method for producing the copolyester of the present invention is produced by a known polymerization method such as a transesterification method or an esterification method. In the transesterification method, an ester-forming derivative of terephthalic acid and ethylene glycol are charged into a reaction vessel and reacted at 150 to 250 ° C. in the presence of a transesterification catalyst, and then a stabilizer, a polycondensation catalyst, etc. are added, It can obtain by heating to 250 to 300 degreeC under reduced pressure, and making it react for 3 to 5 hours.
In the esterification method, terephthalic acid and ethylene glycol are charged into a reaction vessel and subjected to an esterification reaction at 150 to 70 ° C. under nitrogen pressure. After the esterification reaction is completed, a stabilizer, a polycondensation catalyst, etc. are added, and the pressure is reduced to 500 Pa or less. It can obtain by making it heat at 250 to 300 degreeC under, and making it react for 3 to 5 hours.

  In the method for producing the copolyester of the present invention, the addition time of polyethylene glycol is not particularly limited, and may be added together with other raw materials before the esterification reaction or transesterification reaction. After completion, it may be added before the polycondensation reaction starts.

  Polyethylene glycol having a number average molecular weight of 6000 or more can be obtained in a solid state such as flakes and powders. When adding polyethylene glycol, heat it to 70 ° C or higher and add it in a molten state. By sufficiently dispersing it before the start of pressure reduction in the polycondensation reaction, the polyethylene glycol easily reacts with polyethylene terephthalate, and the hygroscopic performance increases. . The obtained copolyester is preferred because the spinnability is improved even with a single fiber, the spinning speed can be increased, the productivity is improved, and a fine fiber can be obtained.

  In the method for producing a copolyester of the present invention, the addition time of the compound represented by the general formula (2) is not particularly limited, and may be added together with other raw materials before the esterification reaction or transesterification reaction. It may be added after the esterification reaction or transesterification reaction is completed and before the polycondensation reaction starts. Moreover, you may add simultaneously with polyethyleneglycol and may add separately.

  In the method for producing the copolyester of the present invention, examples of the transesterification catalyst include zinc acetate, manganese acetate, magnesium acetate, and titanium tetrabutoxide. Examples of the polycondensation catalyst include antimony trioxide, germanium dioxide, titanium tetrabutoxide, and the like. Is mentioned.

  In the method for producing a copolymerized polyester resin composition of the present invention, the polymerization is targeted after the hindered phenolic antioxidant is added to the polycondensation catalyst and then the pressure inside the reactor is reduced to initiate the polycondensation reaction. By adding it until the degree of polymerization is reached, a copolyester resin composition having excellent oxidative degradation resistance can be obtained. In the case of adding a hindered phenolic antioxidant by the above method, if a diol component such as ethylene glycol is brought in and added in a large amount, depolymerization (polyester main chain cleavage reaction) proceeds. Therefore, a method of adding a hindered phenol-based antioxidant alone or adding a master batch containing an antioxidant at a high concentration is preferable. At this time, the hindered phenol-based antioxidant may be added in several divided portions, or may be continuously added with a feeder or the like. The hindered phenol-based antioxidant is added by filling a container made of a polymer that can be dissolved or melted in the polymerization system and is substantially the same as the polymer obtained in the present invention. It is preferable. When the hindered phenolic antioxidant is added to the container as described above and added, the hindered phenolic antioxidant is scattered by adding to the polymerization reactor under reduced pressure conditions, and the decompression line In addition, the hindered phenolic antioxidant can prevent outflow, and a hindered phenolic antioxidant can be added to the polymer in a desired amount. The container referred to in the present invention is not limited as long as hindered phenolic antioxidants can be collected. For example, an injection molded container having a lid or a stopper, or a sheet or film formed into a bag shape by sealing or sewing. Etc. are included. More preferably, the container described above creates an air vent. When a hindered phenolic antioxidant is added to a container that has been vented, even if it is added to the polymerization reactor under vacuum conditions, the container will burst due to air expansion and the hindered phenolic antioxidant will remain in the decompression line. The hindered phenolic antioxidant can be added to the polymer in a desired amount without flowing out into the polymer or adhering to the upper part or the wall surface of the polymerization reactor. If the container is too thick, it will take longer to dissolve and melt, so it is better to make the container thinner. However, ensure that the container does not rupture when hindered phenolic antioxidants are added or added. . For this purpose, a material having a thickness of 10 to 500 μm and uniform thickness is preferable.

  The copolyester obtained by the production method of the present invention is a copolyester having high heat resistance and excellent hygroscopicity. Therefore, the copolyester is suitably used for fibers, films, molded articles, etc. by melt molding. It can be suitably used as a raw material for fibers. In that case, in order to have sufficient hygroscopicity, the moisture absorption parameter (ΔMR) is preferably 2% or more. More preferably, it is 4% or more.

It is more preferable that the hygroscopicity parameter (ΔMR) of the copolyester is 10% or more because it can be used in composite spinning.
Here, the moisture absorption parameter (ΔMR) is 20 ° C. × 65% R.D. H. A sample that had been conditioned and stabilized in a standard state of 30 ° C. × 90% H. It means the value (%) obtained by dividing the weight increase (g) 24 hours after being transferred to the high humidity state by the absolute dry weight (g) of the sample. Here, the absolute dry weight (g) refers to the weight of a sample dried at 105 ° C. and dried until no weight change is observed.

  Although the polyethylene glycol in the copolyester obtained by the production method of the present invention has a number average molecular weight lower than that of the added polyethylene glycol, the degree of thermal decomposition is suppressed, and thus the obtained polymer is hygroscopic. Is fully demonstrated. The number average molecular weight of polyethylene glycol in the obtained polymer is 5000 or more, more preferably 5300 or more.

  The copolymerized polyester obtained by the production method of the present invention adopts known molding methods such as extrusion molding, blow molding, vacuum molding, injection molding and the like, and can be made into various resin molded products. When it is made into a fiber, it is preferable because it easily exhibits moisture absorption performance.

  As a fiber using the copolyester obtained by the production method of the present invention, it is preferable that 20 to 100% by weight of the entire fiber is composed of the copolyester of the present invention. When the amount is less than 20% by weight, the effect of improving moisture absorption / release is hardly seen. From the viewpoint of sufficient moisture absorption / release properties, it is preferable that 50 to 100% by weight of the composition constituting the fiber is composed of the copolymerized polyester composition obtained by the production method of the present invention. In particular, it is more preferable that the entire fiber (100%) is made of the copolyester of the present invention, that is, a substantially single fiber, since the moisture absorption performance of the fiber can be maximized.

  Further, a copolymer polyester having a hygroscopic parameter (ΔMR) of 5% or more is preferably used in composite spinning because the physical properties of the fiber are improved.

  Composite spinning can be spun by a known production method. For example, in the composite fiber of the copolymerized polyester of the present invention and a known polyethylene terephthalate, the respective polymers are separately melted at a melting temperature of 240 to 320 ° C., and the spinning temperature is 240 to 320 ° C. using any composite fiber die. It can be obtained by spinning. The melting temperatures of the polymers may be the same or different.

  The hygroscopicity of the fiber is an important measure that determines the comfort of clothing in hot weather. The moisture absorption parameter (ΔMR) is preferably 2% or more in order to provide comfort when used as clothing. Further, the moisture absorption parameter (ΔMR) is more preferably 4% or more from the viewpoint of comfort.

  The single yarn fineness of the fiber is preferably 10 dtex or less because it is suitable for clothing applications that require hygroscopicity. Since the copolyester obtained by the production method of the present invention can be fiberized with a single yarn, it is possible to obtain fibers with a fine single yarn fineness, and it is also possible to obtain fibers of 1 dtex or less.

  The cross-sectional shape of the synthetic fiber of the present invention is not limited to a circle, but may be an irregular cross-section such as a triangle, a flat shape, or a multi-leaf type. Further, the filamentous form of the synthetic fiber may be either a filament or a staple, and is appropriately selected depending on the application. The fabric form can be appropriately selected according to the purpose, such as woven fabric, knitted fabric, and non-woven fabric.

Hereinafter, the present invention will be described more specifically with reference to examples. In addition, each characteristic value in an Example was calculated | required with the following method.

A. Moisture absorption parameter (ΔMR)
A measurement sample (3 g) was freeze-pulverized and vacuum dried at a drying temperature of 110 ° C. for 24 hours, and its absolute dry weight (Wd) was measured. This sample was subjected to 20 ° C. × 65% R.D. H. The sample was allowed to stand for 24 hours in a thermo-hygrostat (Espec LHU-123) conditioned in the above condition, the weight (W20) of the sample in equilibrium was measured, and then the thermo-hygrostat was set to 30. ° C x 90% R.D. H. The weight after standing for 24 hours (W30) was measured and determined by the following formula 1.
Moisture absorption parameter (ΔMR) = (W30−W20) / Wd (%) (Formula 1)

B. Measurement of number average molecular weight and copolymerization amount of polyethylene glycol contained in copolymerized polyester About 0.05 g of copolymerized polyester was sampled, 1 mL of ammonia water was added, and the sample was dissolved by heating at 120 ° C. for 5 hours. After standing to cool, 1 ml of purified water and 1.5 ml of 6M hydrochloric acid were added, and the volume was adjusted to 5 ml with purified water. After centrifugation, filter through a 0.45 μm filter, measure the molecular weight distribution of the filtrate with GPC, and calculate the number average molecular weight of polyethylene glycol using a molecular weight calibration curve created using a standard sample with a known molecular weight. did. Moreover, polyethylene glycol was quantified using the calibration curve of the solution concentration created with the polyethylene glycol aqueous solution, and the copolymerization amount of the polyethylene glycol in the copolymer was calculated.
Apparatus: Gel permeation chromatograph GPC
Detector: differential refractive index detector RI (RI-8020 manufactured by Tosoh, sensitivity 128x)
Photodiode array detector (SPD-M20A manufactured by Shimadzu Corporation)
Column: TSKgelG3000PWXL (1) (Tosoh)
Solvent: 0.1M sodium chloride aqueous solution flow rate: 0.8 mL / min
Column temperature: 40 ° C
Injection volume: 0.05mL
Standard samples: polyethylene glycol, polyethylene oxide.

C. Polymer IV
The obtained polyester was dissolved in an o-chlorophenol solvent to prepare solutions having concentrations of 0.5 g / dL, 0.2 g / dL, and 0.1 g / dL. Thereafter, the relative viscosity (ηr) at 25 ° C. of the obtained solution having the concentration C was measured with an Ubbelohde viscometer, and (ηr ⁻¹ ) / C was plotted against C. By extrapolating the obtained results to a concentration of 0, the intrinsic viscosity was determined.

D. Color of polymer (L value, b value)
The obtained polymer is rapidly cooled from the melted state, molded into a chip shape, and filled in a quartz glass container. A hunter type color difference meter (SM color computer model SM-3 manufactured by Suga Test Instruments Co., Ltd.) The L value and b value of the hunter were obtained.

E. The cross-sectional slice obtained by cutting the island-diameter measurement pellet of the dispersion structure was stained with osmium, and the blend state was observed and photographed with a transmission electron microscope (TEM) (100,000 times). It has a sea-island structure in which a continuous matrix component (white portion) is a sea component, and a component (gray portion) dispersed in a substantially circular shape is an island component. The island component dispersion diameter is calculated by converting the diameter of the island component into a diameter (assuming the island component is a circle and the diameter converted from the area of the island component). The diameter.

F. Copolymerization rate of BPA component 1H-NMR of the copolymerized polyester resin composition was measured, and the copolymerization amount of the copolymerization component was determined from the integration ratio of the methyl group portion or the aromatic ring portion of the BPA component.

G. Melt Viscosity Retention Ratio It was vacuum dried at 150 ° C. for 10 hours, and measured using Capillograph 1B (manufactured by Toyo Seiki Seisakusho Co., Ltd.) according to JIS 7199: 1999, using an inner diameter of 1 mm and a length of 40 mm.
The shear viscosity (η5) at a shear rate of 243.2 sec-1 at a preheating time of 5 minutes and the shear viscosity (η20) at a shear rate of 243.2 sec-1 at a preheating time of 20 minutes were determined and calculated by the following formula.
Melt viscosity retention (%) = η20 ÷ η5 × 100 (1)

H. Spinnability (single yarn)
Vacuum-dried at 150 ° C. for 10 hours, using a die having a diameter of 0.20 mm, a discharge hole length of 0.55 mm, and 96 holes, a spinning temperature of 290 ° C., a discharge amount of 47.1 g / min, and a spinning speed of 3000 m / min. The yarn breakage frequency when 1 kg spinning was performed was evaluated.
The case where the yarn was not broken once was marked with ◯, the range where the yarn breakage was recognized but there was little trouble in operability was marked with Δ, and the case where yarn breakage occurred frequently was marked with ×.

I. Spinnability (composite yarn)
A copolymer polyester is used as a core component, polyethylene terephthalate having an intrinsic viscosity of 0.70 is melted separately as a sheath component, and using a concentric core-sheath composite die, a spinning temperature of 290 ° C., a total discharge amount of 47.1 g / min, a core / The yarn breakage frequency when 1 kg spinning was performed under the conditions of sheath ratio (weight ratio) = 40/60 and spinning speed of 3000 m / min was evaluated.
The case where the yarn was not broken once was marked with ◯, the range where the yarn breakage was recognized but there was little trouble in operability was marked with Δ, and the case where yarn breakage occurred frequently was marked with ×.

J. et al. Oxidation exothermic test (1) Preparation of a multifilament tube knitted fabric for pretreatment measurement of a sample and washing. Washing conditions are JIS L1096 J-1 method (perchlorethylene method) followed by tumble drying (60 ° C. × 20 minutes). The above pretreatment operation is repeated 10 times.
(2) An oxidation exothermic test test vessel is an iron cylindrical vessel. The inner diameter of the container is 51 mm and the depth is 30 mm. There are 140 holes with a diameter of 5 mm in the side wall of the container, and 25 holes with a diameter of 5 mm in the lid and the bottom.
The test piece is adjusted to a circle with a diameter of 5 cm. Also, prepare a cotton cloth of the same size as the test piece. Test pieces and cotton cloth are alternately stacked and packed in the circular container. At this time, the weight ratio of the test piece is set to 40 to 60% by weight with respect to the sample packed in the cylindrical container.
A thermocouple is inserted in the center of the sample, kept in a gear oven at a constant temperature of 150 ° C. for 100 hours, and the oxidation heat generation of the sample is tested by examining the temperature change and the heat generation state. The case where the temperature did not rise even after holding for 100 hours was judged as ◯, the case where heat was generated between 50 hours and 100 hours was evaluated as Δ, and the case where heat was generated within 50 hours was judged as x.

Example 1
About 100 kg of bis (hydroxyethyl) terephthalate was previously charged in a slurry of 44 kg of high-purity terephthalic acid (Mitsui Chemicals) and 19.7 kg of ethylene glycol (Nippon Shokubai Co., Ltd.) at a temperature of 250 ° C. and a pressure of 1.2 × 10 ^5. The esterification reaction tank maintained at Pa was supplied over 4 hours, and after completion of the supply, the esterification reaction was completed over another 1 hour. Next, 51 kg of this esterification reaction product was transferred to a polycondensation tank.
Subsequently, 30 kg of polyethylene glycol having a molecular weight of 8300 (PEG6000S manufactured by Sanyo Chemical Industries, Ltd.) melted by heating to 70 ° C. in the polycondensation reaction tank to which the esterification reaction product has been transferred, bisphenol-A-ethylene oxide adduct 19 kg of EO addition amount of 4 mol (hereinafter referred to as BPAEO) (Sanyo Kasei Kogyo Co., Ltd. New Pole BPE-40), 81 g of 10% aqueous potassium hydroxide solution diluted with 1000 g of ethylene glycol (8.1 g (alkali metal as potassium hydroxide)) As 0.004 wt%)). After polyethylene glycol is completely dissolved (cleared) in the esterification reaction product, 25 g of trimethyl phosphate is added, 100 g of silicon is added as an antifoaming agent, 20 g of cobalt acetate is added, and 40 g of antimony trioxide is added as a polycondensation catalyst. After polymerization is performed at 290 ° C. under a reduced pressure of 100 Pa, a polyethylene terephthalate sheet is injection-molded when it reaches 85% of the predetermined stirring torque (at 2 hours 30 minutes after the start of the reduced pressure). 500 g of Irganox 1010 (BASF) is packed in a container having a thickness of 0.2 mm and an internal volume of 1000 cm ³ and added from the top of the reaction can. The polycondensation reaction is continued and the polycondensation reaction proceeds to a predetermined stirring torque. After that, it was discharged into cold water in a strand shape and immediately cut to obtain a copolymerized polyester chip.
The copolymerization amount of polyethylene glycol in this copolymer was 29% by weight, the number average molecular weight of polyethylene glycol was 5500, and the BPA amount was 500 mol / ton. The copolymer polyester obtained had an IV of 1.08, a color tone L value of 64.0, a b value of −1.3, and an ΔMR of 9.7%. Furthermore, the melt viscosity retention was 88%, which was very good.
Because of its high moisture absorption performance, it was used as a core polymer for composite spinning. The resulting copolyester chip was vacuum dried at 150 ° C. for 10 hours and subjected to composite spinning. As a result, spinnability was good and yarn breakage was observed. The ΔMR of the obtained fiber was 4.0%, and the fiber had high moisture absorption performance. Further, no temperature increase was caused by the oxidation heat generation test.

Examples 2-15
The same procedure as in Example 1 was conducted except that the EO addition amount and addition amount of BPAEO and the polymerization set torque were changed. The results are shown in Tables 1 and 2.

Comparative Example 1
The same procedure as in Example 1 was carried out except that BPAEO was not added. The results are shown in Table 3.

Comparative Examples 2-10
The same procedure as in Example 1 was performed except that the EO addition amount and addition amount of BPAEO were changed. The results are shown in Table 3.

Examples 16, 17 and Comparative Example 11
The procedure was the same as in Example 1 except that the amount of PEG added was changed. Since the moisture absorption performance (ΔMR) of the obtained polymer was less than 5, the core / sheath ratio (weight ratio) of the composite fiber was set to 80/20. Moreover, in order to confirm the spinnability with a single yarn, the obtained copolymer polyester chip was vacuum-dried at 150 ° C. for 10 hours, and single spinning was performed. The results are shown in Table 4.

Examples 18-22, Comparative Example 12
The procedure was the same as in Example 1 except that the amount of PEG added was changed. The results are shown in Table 4.

Examples 23 to 25, Comparative Examples 13 and 14
The same procedure as in Example 1 was performed except that the molecular weight of PEG was changed. The results are shown in Table 5.

Example 26
Irganox 1010 was changed to 1,3,5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate (Sianox CYNOX CY1790, manufactured by Sun Chemical Co., Ltd.), except that the addition amount was changed. Performed as in Example 1. The results are shown in Table 6.

Example 27
Irganox 1010 was converted to 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl} -2,4,8,10-tetra. This was carried out in the same manner as in Example 1 except that the amount was changed to oxaspiro [5.5] undecane (Adeka Stub AO-80 manufactured by Adeka) and the addition amount was changed. The results are shown in Table 6.

Examples 28-30
The same procedure as in Example 1 was performed except that the amount of Irganox 1010 added was changed. The results are shown in Table 6.
Example 31
Irganox 1010 was changed to bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate (LA-77Y manufactured by Adeka), and the same procedure as in Example 1 was carried out except that the amount added was changed. The results are shown in Table 6.
Example 32
The same procedure as in Example 26 was performed except that the addition amount of PEG and the addition amount of CY1790 in Example 26 were changed. The results are shown in Table 6.
Example 33
The same operation as in Example 27 was performed except that the addition amount of PEG and the addition amount of AO-80 in Example 27 were changed. The results are shown in Table 6.

Example 34
High-purity terephthalic acid (Mitsui Chemicals) 38.5 kg and 1,4-butanediol (BDO) (BASF) 37.6 kg, tetra-n-butoxy titanate (TBT) (Tokyo Chemical Industry) as an esterification reaction catalyst ) 45 g (0.045 wt%) diluted with 100 mL of BDO, 45 g (0.045 wt%) of monobutyltin oxide (MBO) (Tokyo Kasei) are added, and the esterification reaction is carried out at a temperature of 160 ° C. and a pressure of 101 kPa. After the start, the temperature was gradually raised, and the esterification reaction was finally completed under the condition of a temperature of 225 ° C. Next, the entire amount of the esterification reaction product was transferred to a polycondensation tank.
Subsequently, 30 kg of polyethylene glycol having a molecular weight of 8300 (PEG6000S manufactured by Sanyo Chemical Industries) melted by heating to 70 ° C. in the polycondensation reaction tank to which the esterification reaction product was transferred, bisphenol-A-ethylene. An EO addition amount of 4 mol of oxide adduct (hereinafter referred to as BPAEO) (New Pole BPE-40 manufactured by Sanyo Chemical Industries Co., Ltd.) is diluted with 19 kg of potassium hydroxide 10% aqueous solution with 1000 g of ethylene glycol (8.1 g as potassium hydroxide). (0.004% by weight as alkali metal)) was added. After polyethylene glycol is completely dissolved (cleared) in the esterification reaction product, 35 g of phosphoric acid is added, 100 g of silicon is added as an antifoaming agent, and 90 g (0.090 wt%) of TBT is diluted with 100 mL of BDO as a polycondensation catalyst. Is added at a reduced pressure of 100 Pa, and the polymerization is carried out at 250 ° C., and then the polyethylene terephthalate sheet is formed at the time when 85% of the predetermined stirring torque is reached (at the time of 1 hour 30 minutes from the start of the reduced pressure). 500 g of Irganox 1010 (manufactured by BASF) is packed in a container with a thickness of 0.2 mm and an internal volume of 1000 cm ³ created by injection molding, added from the top of the reaction can, and the polycondensation reaction is continued until a predetermined stirring torque is reached. Then, it was discharged into cold water in a strand form and immediately cut to obtain a copolymerized polyester chip.
The copolymerization amount of polyethylene glycol in this copolymer was 29% by weight, the number average molecular weight of polyethylene glycol was 6300, and the BPA amount was 500 mol / ton. The copolymer polyester obtained had an IV of 1.55, a color tone L value of 78.3, a b value of 6.0, and an ΔMR of 12.0%. Furthermore, the melt viscosity retention was 75%, which was good.
Because of its high moisture absorption performance, it was used as a core polymer for composite spinning. The resulting copolyester chip was vacuum dried at 150 ° C. for 10 hours and subjected to composite spinning. As a result, spinnability was good and yarn breakage was observed. The ΔMR of the obtained fiber was 5.0%, and it had high moisture absorption performance. Further, no temperature increase was caused by the oxidation heat generation test.
Examples 35-40, Comparative Example 16
The same procedure as in Example 34 was performed except that the addition amount of BPAEO and the polymerization setting torque were changed. The results are shown in Table 7.

Claims (3)

10 to 50% by weight of polyethylene glycol having a number average molecular weight of 5000 to 20000, a copolymer polyester obtained by copolymerizing 80 to 800 mol / ton of a structure represented by the following general formula (1), and having an island phase in a phase separation structure A copolymer polyester resin composition having a dispersion diameter of 1 to 50 nm.

(However, n and m are integers of 2 to 20, and n + m is 4 to 30) Number average when producing a copolymerized polyester resin composition by polycondensation reaction after esterification or transesterification of aromatic dicarboxylic acid or its ester-forming derivative, diol or its ester-forming derivative, and polyethylene glycol 10 to 50% by weight based on the copolyester from which polyethylene glycol having a molecular weight of 6000 to 20000 can be obtained, and a compound represented by the following general formula (2) is added before the start of the polycondensation reaction by 10 to 30% by weight. The method for producing a copolyester resin composition according to claim 1.

(However, n and m are integers of 2 to 20, and n + m is 4 to 30) The copolymer according to claim 2, wherein a hindered phenol antioxidant is added in an amount of 0.1 to 5.0% by weight based on the polyester obtained after the start of the polycondensation reaction and before the completion of the polycondensation reaction. A method for producing a polyester resin composition.