JP3131100B2 - Polyester composition and its fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

This invention relates to polyester compositions and fibers. More specifically, the present invention relates to a polyester composition having a low viscosity at the time of melting and excellent in moldability, and a fiber which can be dyed with a cationic dye and has excellent physical properties.

[0002]

2. Description of the Related Art Polyesters, especially polyethylene terephthalate, have many excellent properties and are therefore widely used in various applications, especially in fibers and films. In general, a method in which polyester is formed into a fiber or a film, and the degree of polymerization of the polymer is increased in order to improve the strength of the polyester or the like. However, increasing the degree of polymerization naturally also increases the viscosity of the molten polymer, so that the extrusion pressure at the time of molding is increased, the moldability is deteriorated, and the productivity is reduced. Therefore, several measures for reducing the melt viscosity of the polymer have been proposed.
For example, a method of adding a bisphenol compound (Japanese Unexamined Patent Application Publication No.
No. 223382), a method of adding ethylenebisstearic acid acid, a method of adding stearic acid, and the like have been proposed, but each of these methods has a problem that the degree of polymerization of the polyester is also reduced.

[0003] Also, raising the melting temperature at the time of molding is one of the measures for lowering the melt viscosity. However, this method also lowers the degree of polymerization of the polyester, so that the strength of the molded product is improved. Not fit purpose.

[0004] On the other hand, polyester has a drawback of low dyeability. Therefore, various proposals have been made to improve the dyeability of polyester. As one of the methods, there has been known a method in which an isophthalic acid component containing a metal sulfonate, for example, a 5-sodium sulfoisophthalic acid component is copolymerized with a polyester to enable dyeing with a cationic dye (Japanese Patent Publication No. Sho 34). −104
No. 97).

However, in this method, if the isophthalic acid component containing a metal sulfonic acid base is copolymerized in an amount necessary to improve the dyeability to a satisfactory level, the isophthalic acid component containing the metal sulfonic acid salt increases. Due to the viscous effect, the melt viscosity of the polymerization reaction product has increased remarkably, making it difficult to sufficiently increase the degree of polymerization, and at the same time, making the melt molding difficult. Therefore, in order to reduce the melt viscosity of the modified polyester obtained by copolymerizing the isophthalic acid component containing the above amount of the sulfonic acid metal base to a range where the polymerization is easy and the melt molding can be performed, the degree of polymerization of the modified polyester is reduced. It needs to be kept low. As a result, the strength of the resulting molded article is reduced, which significantly limits the use of the resulting cationic dyeable polyester.

Accordingly, several methods have been proposed for lowering the melt viscosity without lowering the degree of polymerization of the polyester (for example, JP-A-5-148415 and JP-A-4-148415).
264126). However, none of these proposed methods is of a level that can be used practically.

[0007]

Therefore, the first aspect of the present invention
An object of the present invention is to provide a polyester composition capable of lowering the viscosity at the time of melting without lowering the degree of polymerization of the polyester. A second object of the present invention is to provide a polyester composition which does not cause molding problems in actual industrial production. A third object of the present invention is to provide a polyester composition which can be molded with a normal melt viscosity for a polyester having a relatively high degree of polymerization, and therefore a polyester having a relatively high viscosity during melt molding. Another object of the present invention is to provide a fiber having sufficient strength and excellent dyeing properties for a cationic dye.

[0008]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the object of the present invention can be achieved by blending a specific sulfonate compound with a specific ratio to polyester. I found it. That is, according to the present invention, isophthalic acid containing an ethylene terephthalate unit as a main repeating unit and containing a metal sulfonate group
The components are copolymerized in an amount of 1 to 15 mol% based on the total dicarboxylic acid components.
Copolymerized polyester and the following general formula (I)

[0009]

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(Where A represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 25 carbon atoms; The hydrocarbon group may be substituted with a hydrocarbon group containing oxygen, nitrogen and halogen, but it does not contain an ester-forming functional group, and M represents an onium group.) the substantially become more sulfonate compounds, and the sulfonate compound is at least 1 wt% blend with respect to the polyester and substantially polyal
There is provided a polyester composition characterized by not containing kylene glycol . Further, according to the present invention, there is provided a fiber formed from the polyester composition.

Hereinafter, the polyester composition of the present invention will be described in more detail. The polyester in the present invention has an ethylene terephthalate unit as a main repeating unit .
Phthalic acid component containing metal sulfonate group
Was copolymerized from 1 to 15 mol% based on the total dicarboxylic acid component.
It is a polymerized polyester. The term "main" used herein means that at least 20 mol%, preferably at most 15 mol%, particularly preferably at most 10 mol%, of a repeating unit other than the ethylene terephthalate component is copolymerized with respect to all the unit components constituting the polyester. Means that you may. Examples of dicarboxylic acid components other than terephthalic acid that can be copolymerized include, for example, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, β-
Examples thereof include aromatic and aliphatic bifunctional carboxylic acids such as hydroxyethoxybenzoic acid, P-oxybenzoic acid, adipic acid, sebacic acid and 1,4-cyclohexadicarboxylic acid.

The diol components other than ethylene glycol which can be copolymerized include, for example, trimethylene glycol, tetramethylene glycol, cyclohexane-
Examples thereof include aliphatic, alicyclic and aromatic diol compounds such as 1,4-dimethanol, neopentyl glycol, bisphenol A and bisphenol S, and polyoxyalkylene glycol.

Further, within the range where the effects of the present invention are not substantially impaired, polycarboxylic acids such as trimellitic acid and pyromellitic acid; and polyols such as glycerin, trimethylolpropane and pentaerythritol are used as copolymerization components. You may.

As the polyester in the present invention, those synthesized by an arbitrary method are used. For example, when polyethylene terephthalate is described, for example, terephthalic acid and ethylene glycol are usually directly esterified, a lower alkyl ester of terephthalic acid such as dimethyl terephthalate is transesterified with ethylene glycol, or terephthalic acid and ethylene glycol are used. A first-stage reaction for producing a glycol ester of terephthalic acid and / or a low polymer thereof by a method of reacting with an oxide; and heating the first-stage reaction product under reduced pressure in the presence of a polymerization catalyst to a desired degree of polymerization. It is produced by a second-stage reaction in which a polycondensation reaction is carried out to the extent possible.

As the polyester constituting the polyester composition of the present invention, an isophthalic acid component containing an ethylene terephthalate unit as a main repeating unit and containing a metal sulfonate group is 1 to 15% by mole, preferably 1.3%, based on the total dicarboxylic acid component. The use of a copolymerized polyester copolymerized at a concentration of about 5 mol% is a particularly preferred embodiment because a fiber having sufficient strength and excellent dyeability with respect to a cationic dye can be obtained.

The isophthalic acid component containing a metal sulfonate group (hereinafter sometimes referred to as S component) used for obtaining the copolymerized polyester is represented by the following general formula (I)
Compounds represented by I), specifically, dimethyl (5
-Sodium sulfo) isophthalate, bis-2-hydroxyethyl (5-sodium sulfo) isophthalate, bis-4-hydroxybutyl (5-sodium sulfo) isophthalate, and the like.

[0017]

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(Where Z represents an alkali metal such as Na, Li or K, and B and B 'represent H, CH ₃ or-(C
H ₂ ) _n OH. n shows the integer of 2-5. )

The preferred S component is dimethyl (5-
Sodium sulfo) isophthalate and bis-2-hydroxyethyl (5-sodium sulfo) isophthalate.

The polyester used in the present invention is:
Any polymer may be used as long as it has a degree of polymerization used as a fiber or film. As described above, the present invention has an excellent effect of reducing the melt viscosity with respect to a polyester having a relatively high degree of polymerization. Accordingly, in the present invention, a polyester having an intrinsic viscosity (IV) of at least 0.6, preferably 0.62 to 1.50, particularly preferably 0.64 to 1.00, measured according to the method described below, is used. It is appropriate to do.

The sulfonate compound used in the present invention is represented by the following general formula (I).

[0022]

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In the general formula (I), A represents 1 carbon atom.
-25, preferably 1-20 aliphatic hydrocarbon groups, 3-25 carbon atoms, preferably 3-20 alicyclic hydrocarbon groups or 6-35, preferably 6-25 aromatic hydrocarbons Group. These hydrocarbon groups do not contain ester-forming functional groups, but may contain other substituents.
For example, it may be substituted by at least one kind of hydrocarbon group containing oxygen, nitrogen and halogen. M represents an onium group, and may be, for example, either a phosphonium group or an ammonium group, but M is generally preferably a phosphonium group.

Sulfonate anion in such a sulfonate compound

[0025]

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Specific examples of (substituted) phenylsulfonates, such as phenylsulfonate, butylphenylsulfonate, octadecylphenylsulfonate, dibutylphenylsulfonate, naphthylsulfonate, disisopropylnaphthylsulfonate, dibutylnaphthylsulfonate, naphthalenedisulfonate, etc. Examples include naphthyl sulfonates, butyl sulfonate, octyl sulfonate, lauryl sulfonate, alkyl sulfonates such as hexadecyl sulfonate, and the like, and these may be a mixture.

On the other hand, onium cation

[0028]

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Specific examples of tetramethylphosphonium, tetraethylphosphonium, tetrabutylphosphonium, triethylmethylphosphonium, tributylmethylphosphonium, tributylethylphosphonium, trimethylbutylphosphonium, trimethyloctylphosphonium, trimethyllaurylphosphonium, trimethylstearylphosphonium, triethyloctyl Examples include aliphatic phosphonium such as phosphonium and tributyloctylphosphonium, and aromatic phosphonium such as triphenylmethylphosphonium, triphenylethylphosphonium, triethylbenzylphosphonium, and tributylbenzylphosphonium.

Further, other specific examples of the onium cation include tetramethyl ammonium, tetraethyl ammonium, tetrabutyl ammonium, triethyl methyl ammonium, tributyl methyl ammonium, tributyl ethyl ammonium, trimethyl butyl ammonium, trimethyl octyl ammonium, trimethyl lauryl ammonium, Aliphatic ammonium such as trimethylstearyl ammonium, trimethyloctylammonium, and tributyloctylammonium, and ammonium containing an aromatic group such as triphenylmethylammonium, triphenylethylammonium, triethylbenzylammonium, and tributylbenzylammonium are also included.

The sulfonate compound of the general formula (I) may be added to the polyester at any stage before the completion of the molding of the polyester, preferably at any stage before the molding of the polyester is started. However, specifically, it may be added at a stage before the synthesis of the polyester is completed, or after the completion of the synthesis of the polyester,
It may be kneaded into the polyester using a shaft ruder. Further, it may be molded while directly kneading the polyester pellets during spinning.

In the polyester composition of the present invention, the compounding ratio of the sulfonate compound is at least 1% by weight, preferably 1.5 to 20% by weight, based on the polyester.
In particular, the content is desirably 2 to 10% by weight. 1% by weight
If it is less than 20, the effect of reducing the melt viscosity is not exhibited, while
If the amount is more than 10% by weight, the hue of the polyester deteriorates, the thermal stability decreases, and the degree of polymerization decreases.

The polyester composition of the present invention may contain, if necessary, various additives such as an ether bond inhibitor, a stabilizer, a coloring inhibitor, a heat-resistant agent, a flame retardant, an antioxidant, a matting agent, a coloring agent, It can contain inorganic fine particles and the like.

Thus, the polyester composition of the present invention can be molded stably under a wide range of molding conditions. For example, at the time of spinning, a method of spinning at a speed of 500 to 2500 m / min, stretching and heat treatment,
Spinning at a speed of 00 m / min and simultaneous or subsequent drawing and false twisting. Spinning at a high speed of 5,000 m / min or more. Then, the yarn can be made.

When forming into a film or a sheet, a method of imparting anisotropy by applying tension only in one direction after film formation, a method of stretching in two directions simultaneously or in an arbitrary order, a method of forming two or more steps Arbitrary conditions such as a multi-stage stretching method can be employed without any hindrance, and the industrial significance of the present invention is extremely large.

Particularly, in the polyester composition of the present invention, when a copolymerized polyester obtained by copolymerizing an isophthalic acid component containing a metal sulfonate group is used as the polyester, the fiber formed from the composition is converted into a cationic dye. In addition to having excellent dyeability,
It has high strength and sufficient physical properties. For example, the silk factor (SF) of the obtained fiber is 25 or more.

[0037]

The present invention will be described in more detail with reference to the following examples. In addition, the part in an Example represents a weight part, and each measured value followed the following method. Intrinsic viscosity [IV] of the polymer was determined from a value measured at 35 ° C. with a 0.6 g / 50 ml orthochlorophenol solution. Melt flow index temperature: 285 ° C, diameter: 2.095 at 2160 g load
The melt flow index was measured as the amount of molten polymer extruded from an orifice having a length of 8 mm and a length of 8 mm for 10 minutes. The larger this value is, the lower the melt viscosity is.

Melt viscosity (MV) Using a rotary cylinder viscometer, temperature 280 ° C., shear rate 1
The melt viscosity (MV) of the polymer was measured at 10 / sec. The spinning tone polymer is chipped according to a conventional method, dried, and then 0.3 m
285 ° C. from a spinneret having 24 circular spin holes of m
And the number of yarn breaks per ton of polymer when spun at a take-off speed of 1100 mm / min. A practically acceptable level is 5.0 (number of times of thread breakage / ton) or less. The elongation (El) and the strength (g / de) were measured using a silk factor (SF) tensilon type tensile tester, and calculated by the following equation. If the value of the silk factor is 25 or more, there is no practical problem.

[0039]

(Equation 1)

[0040] dyeing cationic dye Cathilon CD-FRLH / C
athilon Blue CD-FBLH = 1 at a temperature of 120 ° C in a dye bath containing 2% owf (containing 3 g / l of sodium sulfate and 0.3 g / l of acetic acid as an auxiliary agent) at 120 ° C.
Stained for minutes. The obtained yarn was evaluated visually.

Examples 1 to 13 and Comparative Example 1 Examples 1 to 13 are all comparative reference examples of the present invention. 100 parts of dimethyl terephthalate, ethylene glycol 60
Parts, 0.032 parts of manganese acetate tetrahydrate (0.025 mol% based on dimethyl terephthalate) was charged into a transesterification vessel, and the temperature was raised from 140 ° C. to 220 ° C. over 3 hours under a nitrogen gas atmosphere. The transesterification reaction was performed while distilling the generated methanol out of the system. Next, after adding 0.020 parts of trimethyl phosphate as a stabilizer, the temperature was raised to drive out excess ethylene glycol. After 10 minutes, 0.04 part of antimony trioxide (0.027 part to dimethyl terephthalate) was used as a polycondensation reaction catalyst.
Mol%) was added. When the internal temperature reached 240 ° C., the purging of ethylene glycol was terminated, and the reaction product was transferred to a polymerization vessel.

Then, the reaction was carried out at normal pressure for 30 minutes while raising the temperature. After that, the pressure was reduced from 760 mmHg to 1 mmHg over 1 hour, and the internal temperature was raised to 290 ° C. over 1 hour and 30 minutes. The polymerization temperature is 290 under reduced pressure of 1 mmHg or less.
When the polymerization was further performed at 2 ° C. for 2 hours, the polymerization reaction was terminated by breaking the vacuum with nitrogen gas, the polymer was discharged at 290 ° C. under nitrogen gas pressurization, cooled with water and cut into pellets. The polyester thus obtained has an intrinsic viscosity of 0.1.
78.

The compounds shown in Table 1 were blended with the above-mentioned polyester pellets, melt-mixed with a vented twin-screw extruder, and the resulting polyester composition was extruded into strands, cooled with water, and then recut into pellets. . Table 1 shows the melt flow index and the intrinsic viscosity of the obtained polyester composition.

[0044]

[Table 1]

In the above Table 1, A to L respectively mean the following sulfonate compounds.

[0046]

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Examples 14 to 16 and Comparative Example 2 100 parts of dimethyl terephthalate, ethylene glycol 6
0 parts, 0.032 parts of manganese acetate tetrahydrate (0.025 mol% based on dimethyl terephthalate), and the amount of dimethyl 5-sodium sulfoisophthalate shown in Table 1 were charged into a transesterification vessel, and the mixture was placed under a nitrogen gas atmosphere. 14 hours over 3 hours
The transesterification reaction was carried out while distilling the methanol generated by raising the temperature from 0 ° C. to 220 ° C. out of the system. Next, after adding 0.020 parts of trimethyl phosphate as a stabilizer, the temperature was raised to drive out excess ethylene glycol. After 10 minutes, 0.04 parts of antimony trioxide (0.02 part based on dimethyl terephthalate) was used as a polycondensation reaction medium.
7 mol%). When the internal temperature reached 240 ° C., the purging of ethylene glycol was terminated, and the reaction product was transferred to a polymerization vessel.

Then, the reaction was carried out at normal pressure for 30 minutes while increasing the temperature. After that, the pressure was reduced from 760 mmHg to 1 mmHg over 1 hour, and the internal temperature was raised to 290 ° C. over 1 hour and 30 minutes. The polymerization temperature is 285 under reduced pressure of 1 mmHg or less.
At the time of further polymerization at 2 ° C. for 2 hours, the sulfonate compounds shown in Table 2 were added, and the mixture was further stirred and polymerized under reduced pressure of 1 mmHg or less for 30 minutes, and then the vacuum was released with nitrogen gas to terminate the polymerization reaction. The polymer was discharged at 285 ° C. under gas pressurization, cooled with water and cut into pellets. A and F in Table 2 mean the same sulfonate compounds as shown in Table 1 above. Table 2 shows the melt flow index and the intrinsic viscosity of the obtained polyester composition.

[0049]

[Table 2]

Examples 17 to 22 and Comparative Examples 3 to 6 100 parts of dimethyl terephthalate, ethylene glycol 6
0 parts, the amount of metal sulphonate group-containing isophthalic acid component described in Table 3 described in Table 3, 0.14 parts of sodium acetate (0.20 mol% based on dimethyl terephthalate), 0.03 parts of manganese acetate tetrahydrate (0.024 mol% based on dimethyl terephthalate) and cobalt acetate 4
0.09 parts of water salt (0.0 to dimethyl terephthalate)
(07 mol%) in a transesterification vessel, and the temperature was raised from 140 ° C. to 220 ° C. over 3 hours in a nitrogen gas atmosphere, and a transesterification reaction was performed while distilling off the generated methanol out of the system.

After stirring at 220 ° C. for 20 minutes,
As a stabilizer, 0.03 parts of a 56% aqueous solution of orthophosphoric acid (0.033 mol% based on dimethyl terephthalate) was added, and at the same time, the temperature was raised and the excess ethylene glycol was removed. After 10 minutes, 0.04 parts of antimony trioxide (0.027 mol% based on dimethyl terephthalate) was added as a polycondensation medium. When the internal temperature reached 240 ° C., the purging of ethylene glycol was terminated, and the reaction product was transferred to a polymerization vessel.

Then, the reaction was carried out at normal pressure while raising the temperature until the internal temperature reached 260 ° C., and then 760 mm over 1 hour.
The pressure was reduced from Hg to 1 mmHg, and at the same time, the internal temperature was raised to 280 ° C. over 1 hour and 30 minutes. When the polymerization was further performed at a polymerization temperature of 280 ° C. for 2 hours under a reduced pressure of 1 mmHg or less, the sulfonium sulfonate of Table 3 was added in an amount shown in Table 3, and the reaction was further performed under reduced pressure for 30 minutes. Break the vacuum with nitrogen gas to end the polymerization reaction,
Discharging was performed at 280 ° C. under nitrogen gas pressure to obtain polymers having the quality shown in Table 3.

The polymer was formed into chips according to a conventional method, dried, melted and discharged at 285 ° C. from a spinneret having 24 circular spinning holes having a diameter of 0.3 mm, and melt-spun at a take-up speed of 1100 m / min. did. The spinning condition at this time was as shown in Table 3. Then, the obtained undrawn yarn is drawn at a draw ratio at which the elongation of the finally obtained drawn yarn is 30%,
Drawing and heat treatment were performed using a supply roller at 84 ° C. and a plate heater at 180 ° C. to obtain a drawn yarn of 75 denier / 24 filaments. Intrinsic viscosity (IV) of the obtained drawn yarn
, Strength and silk factor are shown in Table 3.

A fabric made of the drawn yarn is used as a cationic dye Catilon CD-FRLH / Cathilon.
Dye bath containing 2% owf of Blue CD-FBLH = 1/1 (manufactured by Hodogaya Chemical Co., Ltd.)
Liter, containing 0.3 g / liter of acetic acid)
Stained at 20 ° C. for 60 minutes. The staining properties were as shown in Table 3. In Table 3, in the type of phosphonium sulfonate, A-1 and A-2 represent the following compounds, respectively.

[0055]

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[0056]

[Table 3]

As is clear from the results in Table 3, the polyester compositions of the present invention (Examples 17 to 23) can suppress the rise in melt viscosity and sufficiently increase the degree of polymerization, and The condition is good, and the strength of the obtained fiber is also excellent. On the other hand, when the copolymerization amount of the metal sulfonate group-containing isophthalic acid component is less than 1.0 mol% and the addition amount of the sulfonate compound is less than 1 wt% (Comparative Example 3), the cationic dye is used. No clear dyeing properties can be obtained.

When no phosphonium sulfonate was blended (Comparative Examples 4 and 6), when the blended amount of phosphonium sulfonate was less than 1% by weight (Comparative Example 5)
However, since the effect of suppressing thickening cannot be obtained, the degree of polymerization cannot be sufficiently increased, the spinning condition is poor, and the strength of the obtained fiber is also low.

[0059]

Industrial Applicability The polyester composition of the present invention suppresses the phenomenon of thickening, can sufficiently increase the degree of polymerization, and stably forms fibers and films without impairing the excellent mechanical properties of polyester. It can be melt molded. Such a polyester composition of the present invention can be used, for example, for a high-strength cationic dye-dyed type modified polyester fiber, and its industrial significance is extremely large.

Continuation of the front page (56) References JP-A-5-214229 (JP, A) JP-A-5-31115 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08J 5 / 00 C08L 67/00-67/02

Claims (3)

(57) [Claims] 1. An isophthalocyanate having an ethylene terephthalate unit as a main repeating unit and containing a metal sulfonate group.
The tallic acid component is used in an amount of 1 to 15 mol% based on the total dicarboxylic acid component.
Polymerized copolymerized polyester and the following general formula (I) (Where A is an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an alicyclic hydrocarbon group having 3 to 20 carbon atoms, or 6 carbon atoms)
To 25 aromatic hydrocarbon groups, which may be substituted with a hydrocarbon group containing oxygen, nitrogen and halogen, but do not contain an ester-forming functional group. M represents an onium group. ), And at least 1% by weight of the sulfonic acid compound with respect to the polyester, and substantially comprises a polyalkylene glycol.
A polyester composition containing no coal . 2. An intrinsic viscosity of at least 0.6 determined from a value measured in an orthochlorophenol solution at 35 ° C.
The polyester composition according to claim 1, which is: 3. A fiber formed from the polyester composition according to claim 1.