JPH01103650A - Improved polyester composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. having excellent heat resistance and being dyable with cationic dyes, by compounding an alkali (earth) metal org. carboxylate with a specified improved polyester CONSTITUTION:An improved polyester (a) is obtd. by copolymerizing a polyester with 0.05-20mol.% phosphonium sulfonate of the formula (wherein A is an arom. group or an aliph. group; X1 is an ester-forming functional group; X2 is X1, another different ester-forming functional group or H; R1-4 are each alkyl or aryl; n is a positive integer) based on the difunctional carboxylic acid component constituting the polyester. Then, 0.002-0.2mol.% alkali (earth) metal org. carboxylate based on the acid component excluding the sulphonate constituting the component (a) is compounded with the component (a).

Description

Detailed Description of the Invention <Industrial Field of Application> The present invention relates to a modified polyester composition, more specifically a cationic dye having a sufficient degree of polymerization and excellent heat resistance suitable for melt molding, especially melt spinning. This invention relates to a dyeable modified polyester composition.

<Prior Art> Polyester has many excellent properties and is therefore widely used as fibers and films, but it has poor dyeability and 1. It is particularly difficult to dye with dyes other than disperse dyes. Various proposals have been made to improve this dyeability. One of the methods is to copolymerize polyester with an isophthalic acid component containing a sulfonic acid metal base, for example, a 5-sodium sulfoisophthalic acid component, thereby making it dyeable with cationic dyes (Japanese Patent Publication No. 3, Sho 3).
(See Publication No. 4-10497).

However, in this method, when the isophthalic acid component containing the sulfonic acid metal base is copolymerized in an amount necessary to increase the dyeability to a satisfactory level, the thickening effect of the isophthalic acid component containing the sulfonic acid metal base causes The melt viscosity of the polymerization reaction product increases significantly, making it difficult to sufficiently increase the degree of polymerization and also making melt molding difficult.

Therefore, in order to reduce the melt viscosity of a modified polyester copolymerized with an isophthalic acid component containing such an amount of sulfonic acid metal base to a range where polymerization is easy and melt molding is possible, the degree of polymerization of the modified polyester must be adjusted. Need to keep it low. As a result, the strength of the molded product decreases,
This significantly limits the uses of the resulting cationic dye-dyeable polyester.

On the other hand, a method is known in which an isophthalic acid component having a sulfonic acid phosphonium base is used as a cationic dye dyeing agent (Japanese Patent Publication No. 47-22334).

According to this method, the thickening effect during the polymerization reaction is small, so even if the degree of polymerization of the modified polyester is increased, the melt viscosity can be kept within the range that can normally be used for melt spinning. . Therefore, high-strength cationic dyeable polyester fibers can be easily obtained.

However, in this method, the heat resistance of the isophthalic acid component having a sulfonate phosphonium base used is inferior to that of the isophthalic acid component having a sulfonate metal base, so that It has the serious disadvantage that it decomposes under high heat conditions or accelerates the decomposition of the polymer, causing the produced polyester and molded products to turn yellowish brown, and also significantly lowering the degree of polymerization of the polyester. This will worsen the color tone. For this reason, this method has never been industrially adopted.

<Problems to be Solved by the Invention> In view of the advantages of the modified polyester copolymerized with an isophthalic acid component containing a phosphonium sulfonate base, the present inventor conducted intensive studies to overcome the above-mentioned disadvantages.
By adding an organic carboxylic acid metal salt of an alkali metal or alkaline earth metal to the production reaction system of the modified polyester, the above-mentioned disadvantage of poor heat resistance can be significantly improved, resulting in high whiteness, high degree of polymerization, and It has been found that a modified polyester dyeable with cationic dyes having good heat resistance can be obtained. Furthermore, it has been found that the mechanical properties such as strength and Young's modulus of the resulting molded products, such as fibers and films, are significantly improved.

The reason for this is not clear, but even if the above-mentioned organic carboxylic acid metal salt is added to a polyester that does not contain a sulfonate phosphonium base, the above effects cannot be obtained at all. It is believed that a special interaction occurs between the component and the organic carboxylic acid metal salt.

The present invention is based on the above findings, and as a result of further studies,
It is completed.

<Structure of the invention> That is, the present invention is based on the following general formula (I)
I) A modified polyester copolymerized with a sulfonic acid phosphonium salt represented by ■(so30p■RI R2R3Rt)□, an organic carboxylic acid metal salt of at least one metal selected from alkali metals and alkaline earth metals,
This relates to a modified polyester composition containing 0.002 to 0.2 mol % of the difunctional carboxylic acid component (excluding sulfonate) constituting the modified polyester.

The polyester in the present invention is a polyester having terephthalic acid as the main acid component and at least one type of glycol, preferably at least one alkylene glycol selected from ethylene glycol, trimethylene glycol, and tetramethylene glycol as the main glycol component. The main target is

It may also be a polyester in which part of the terephthalic acid component is replaced with another difunctional carboxylic acid component, and/
Alternatively, it may be a polyester in which part of the glycol component is replaced with the above-mentioned glycol or other diol component other than the main component.

Examples of the difunctional carboxylic acids other than terephthalic acid used here include isophthalic acid, naphthalene dicarboxylic acid, and diphenyl dicarboxylic acid.

Examples include aromatic, aliphatic, and alicyclic difunctional carboxylic acids such as diphenoxyethanedicarboxylic acid, β-hydroxyethoxybenzoic acid, 1p-oxybenzoic acid, adipic acid, sebacin a, and 1,4-cyclohexanedicarboxylic acid. be able to. Furthermore, isophthalic acid having a sulfonic acid metal base such as 5-sodium sulfoisophthalic acid may be used as a copolymerization component within a range where the effects of the present invention can be substantially achieved.

In addition, as diol compounds other than the above glycols,
Examples include aliphatic, alicyclic, and aromatic diol compounds such as cyclohexane-1,4-dimetatool, neopentyl glycol, bisphenol A, and bisphenol S, and polyoxyalkylene glycols.

Additionally, polycarboxylic acids such as trimellitic acid, pyromellitic acid, glycerin, trimethylolpropane to the extent that the polyester is substantially linear.

Polyols such as pentaerythritol can be used.

Such a polyester can be synthesized by any method.
For example, in the case of polyethylene terephthalate, usually terephthalic acid and ethylene glycol are 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 transesterified. The first stage reaction is to react with terephthalic acid to produce a glycol ester and/or its low polymer, and the first stage reaction product is heated under reduced pressure until the desired degree of polymerization is achieved. It is produced by a second step of polycondensation reaction.

The sulfonic acid phosphonium salt used as a copolymerization component in the method of the present invention has the following general formula (I>Xs A
X2 ・Old...(I)(So!GIP
■RI R2Rs Ra) In the 0 formula represented by n,
A represents an aromatic group or an aliphatic group, and a'X1 is preferably an aromatic group, and a'X1 represents an ester-forming functional group, such as (-CH2gaOH).

0 + CH2+-r-1-0 (CHz) B÷,
OH1°r (wherein R' is a lower alkyl group or a phenyl group), etc. X2 represents the same or different ester-forming functional group or hydrogen atom as Xl, and is preferably an ester-forming functional group, R,, R2,
R3 and R4 represent the same or different groups selected from the group consisting of alkyl groups and aryl groups, and n is a positive integer.

Such sulfonic acid phosphonium salts can generally be easily synthesized by reacting the corresponding sulfonic acid with phosphines or by reacting the corresponding sulfonic acid metal salt with phosphonium halides.

Preferred specific examples of the sulfonic acid phosphonium salts include 3,5-dicarboxybenzenesulfonic acid tetrabutylphosphonium salt, 3,5-dicarboxybenzenesulfonic acid ethyltributylphosphonium salt, and benzyl 3,5-dicarboxybenzenesulfonate. Tributylphosphonium salt, 3.5-dicarboxybenzenesulfonic acid phenyltributylphosphonium salt, 3,5. -Dicarboxybenzenesulfonic acid tetraphenylphosphonium salt, 3゜5-dicarboxybenzenesulfonic acid butyltriphenylphosphonium salt, 3,5-dicarboxybenzenesulfonic acid butyltriphenylphosphonium salt, 3,5-dicarboxybenzenesulfonic acid Benzyltriphenylphosphonium salt, 3,5-dicarbomethoxybenzenesulfonic acid tetrabutylphosphonium salt, 3,
5-Dicarbomethoxybenzenesulfonic acid ethyltributylphosphonium salt 1315-Dicarbomethoxybenzenesulfonic acid benzyl 1heryptylphosphonium salt, 3
．． 5-dicarbomethoxybenzenesulfonic acid phenyltributylphosphonium salt, 3.5-dicarbomethoxybenzenesulfonic acid tetraphenylphosphonium salt, 3.
5-dicarbomethoxybenzenesulfonic acid ethyltriphenylphosphonium salt, 3.5-dicarbomethoxybenzenesulfonic acid butyltriphenylphosphonium salt, 3
．． 5-dicarbomethoxybenzenesulfonic acid benzyltriphenylphosphonium salt.

3-carboxybenzenesulfonic acid tetrabutylphosphonium salt, 3-carboxybenzenesulfonic acid tetraphenylphosphonium salt, 3-carbomethoxybenzenesulfonic acid tetrabutylphosphonium salt, 3-carbomethoxybenzenesulfonic acid tetraphenylphosphonium salt, 3.5- Di(β-hydroxyethoxycarbonyl)benzenesulfonic acid tetrabutylphosphonium salt, 3.5
-Di(β-hydroxyethoxycarbonyl)benzenesulfonic acid tetraphenylphosphonium salt, 3-(β-hydroxyethoxycarbonyl)benzenesulfonic acid tetrabutylphosphonium salt, 3-(β-hydroxyethoxycarbonyl)benzenesulfonic acid tetraphenylphosphonium salt , 4-hydroxyethoxybenzenesulfonic acid tetrabutylphosphonium salt, 2,6-dicarpoxynaphthalene-4-sulfonic acid tetrabutylphosphonium salt, α-tetrabutylphosphonium sulfosuccinic acid, and the like. The above-mentioned sulfonic acid phosphonium salts may be used alone or in combination of two or more.

In order to copolymerize the sulfonic acid phosphonium salt into a polyester, it may be added at any stage before the synthesis of the polyester described above is completed, preferably at any stage before the first stage reaction is completed. Although any method can be used for addition, it is preferable to add it in the form of a solution or slurry of the same glycol as the glycol constituting the polyester.

The proportion of the sulfonic acid phosphonium salt copolymerized with the polyester is suitably in the range of 0.05 to 20 mol%, based on the bifunctional carboxylic acid component (excluding the sulfonate) constituting the polyester, and 0.5 The copolymerization ratio is preferably in the range of ~10 mol%. If the copolymerization ratio is less than 0.05 mol%, the resulting copolymerized polyester tends to have insufficient dyeability with cationic dyes, and if it exceeds 20 mol%, cationic dyeing The physical properties of the polyester no longer show any significant improvement, and on the contrary, the physical properties of the polyester deteriorate, making it difficult to achieve the object of the present invention.

The organic carboxylic acid metal salt used for improving heat resistance in the present invention is preferably a salt of a linear aliphatic carboxylic acid or an aromatic carboxylic acid and an alkali metal or alkaline earth metal. Preferred specific examples include: Acetic acid, propionic acid, myristic acid.

Sodium, potassium, and lithium salts of palmitic acid, stearic acid, montanic acid, benzoic acid, etc.

You can give calcium salts. Especially acetic acid.

Preferred are sodium salts of montanic acid and benzoic acid.

The amount of organic carboxylic acid metal salt used is 0 based on the acid component (excluding sulfonate) that is the raw material for polyester.
．． 0.002 to 0.2 mol%. If the amount of organic carboxylic acid metal salt added is less than 0.002 mol%, the effect of improving thermal stability will not be expressed, and even if it is used in an amount greater than 2.0 mol%, no significant increase in heat resistance improvement will be observed, and on the contrary, The resulting modified polyester is colored yellow and has disadvantages such as decreased mechanical properties.

The organic carboxylic acid metal salt may be added at any stage before the synthesis reaction of the polyester is completed.
In particular, it is preferable to add the sulfonic acid phosphonium salt before the completion of the first-stage reaction, and the sulfonic acid phosphonium salt may be added simultaneously or separately in any order.

<Effects of the Invention> According to the present invention, polymer discoloration and polymerization degree decrease during melt molding and polymerization reaction due to the presence of sulfonic acid phosphonium salt are significantly suppressed, resulting in high whiteness and high polymerization degree. It becomes possible to industrially obtain cationically dyeable polyester molded articles. In addition, weather resistance has also improved in response to improved heat resistance.

The thus obtained modified polyester obtained by copolymerizing a phosphonium sulfonate salt has the following advantages over the conventional modified polyester obtained by copolymerizing a metal sulfonate salt.

(1) Compared to the metal ion of the sulfonate metal salt, the phosphonium salt of the sulfonate salt is bulkier, and the diffusion rate of the cationic dye is higher, so in the case of the sulfonate phosphonium salt, a smaller amount of the phosphonium salt is used. When used, it has the characteristics of providing cationic dyeing properties comparable to those of sulfonic acid metal salts, and of being flattened in vividness.

(2) Since the thickening effect inherent to sulfonic acid metal salts does not occur, melt spinning of highly polymerized polymers can be easily carried out using normal spinning methods, resulting in high-strength cationic dye-dyeable polyester moldings. can be easily obtained.

(31 According to the present invention, since a phosphonium salt is used instead of a metal salt, the amount of foreign substances produced as a by-product during the polycondensation reaction is small,
The effect is that the increase in pack pressure during molding, particularly during spinning, and the decrease in the quality of the obtained yarn are small.

(4) Above +21. Regarding +31, the modified polyester obtained by the method of the present invention has extremely excellent spinnability, and the take-up speed is 3000 m / min or more, especially 50 m / min.
Spinning is possible even at ultra-high speeds of 00 m/min or higher, and yarns with sufficient strength can be obtained with only one winding operation. Furthermore, it is possible to spin ultrafine fibers of 1 denier or less.

(5) The fibers obtained from the modified polyester composition of the present invention have excellent heat resistance, so even when false-twisting is performed at high temperatures, there is no problem of strength loss or fusion, and the fibers are excellent processed yarns. It can give vivid colors when dyed with cationic dyes.

(61゛) Moreover, since the modified polyester composition of the present invention contains a phosphonium salt, it has excellent flame retardancy and antibacterial properties.

The modified polyester composition of the present invention may optionally contain optional additives 1 such as catalysts, color inhibitors, heat resistant agents, flame retardants, antioxidants, matting agents 1 colorants, inorganic fine particles, etc. It may be

<Example> Examples will be given below for further explanation. Parts and % in the examples indicate parts by weight and % by weight, respectively, unless otherwise specified. The intrinsic viscosity [η] of the polymer was determined from the value measured in an orthochlorophenol solution at 35°C, and the softening point (sp
) was measured using the penetration method. The hue of the polymer is indicated by the L value and b value measured by a Hunter color difference meter. The larger the L value, the better the white skin, and the larger the b value, the stronger the yellowness.

The number of terminal carboxyl groups in the polymer was determined by heating and dissolving a sample in benzyl alcohol and titrating with a sodium hydroxide solution. The larger the number of terminal carboxyl groups, the more thermal decomposition occurs.

The diethylene glycol content (DEG content) in the polymer was determined by hydrating a polyester sample, thermally decomposing it with drazine, and subjecting the supernatant to gas chromatography (using 1,4-butanediol as an internal standard).

The heat resistance of the polymer is determined by adjusting the nitrogen gas pressure for extruding the polymer from the polymerization vessel after the polymerization reaction of the copolymer is completed, and setting the time required for polymer extraction to be at least 60 minutes. Intrinsic viscosity of polymer [η
] was evaluated based on the difference.

In addition, the softening point (sp), hue, number of terminal carboxyl groups, and DEC content of the polymer were measured for the polymer 30 minutes after the start of polymer extraction.

Examples 1 to 3 and Comparative Examples 1 to 2 100 parts of dimethyl terephthalate, 6 parts of ethylene glycol
0 parts, 0.03 parts of manganese acid tetrahydrate (0.024 mol % based on dimethyl terephthalate) and 0.009 parts of cobalt acetate tetrahydrate (0.009 parts based on dimethyl terephthalate) as a coloring agent. 007 mol%) and sodium acetate in the amount listed in Table 1 as an organic carboxylic acid metal salt were charged into a transesterification tank, and the mixture was heated at 140° for 3 hours under a nitrogen gas atmosphere.
The temperature was raised from C to 220° C., and the resulting methanol was distilled out of the system to carry out the transesterification reaction. Subsequently, 20% of 3,5-dicarboxybenzenesulfonic acid tetra-n-butylphosphonium salt was added to the obtained product in the amount listed in Table 1.
After adding as a heated ethylene glycol solution and stirring at 220°C for 20 minutes, 0.03 parts of a 56% aqueous solution of orthophosphoric acid (0.0 parts relative to dimethyl terephthalate) was added as a stabilizer.
33 mol %) was added, and at the same time, expulsion of excess ethylene glycol was started at elevated temperature. After 10 minutes, 0.04 part of antimony trioxide (0.027 mol % based on dimethyl terephthalate) was added as a polycondensation catalyst. When the temperature of the indoor bath reached 240℃, we stopped expelling ethylene glycol.
The reaction product was transferred to a polymerization vessel. Next, the reaction was carried out under normal pressure while increasing the temperature until the internal temperature reached 260°C, and then the pressure was reduced from 760 m+nH (l) to Bg for 1 hour, and at the same time the internal temperature was raised to 280°C over 1 hour and 30 minutes. Don't raise the temperature
After further polymerization for 2 hours at a polymerization temperature of 280°C under a reduced pressure of l + nmtl () or less, the vacuum was broken with nitrogen gas to terminate the polymerization reaction, and the polymer was discharged at 280°C under nitrogen gas pressure. The evaluation results of quality and heat resistance were as shown in Table 1.

The polymer is chipped according to a conventional method, dried, and the pore size is 0.
The undrawn yarn obtained was melt-spun at 285°C using a spinneret with 24 circular spinning holes of 3.5 mm, and the elongation of the finally obtained drawn yarn was 30%. The yarn was drawn and heat-treated at a drawing ratio of 84°C using a feed roller at 84°C and a plate heater at 180°C to obtain a drawn yarn of 75 denier/24 filaments.

Table 1 shows the intrinsic viscosity [η]f and strength of the drawn yarn obtained.

The fabric made of this drawn yarn is dyed with cationic dye Cathilo.
n CD-FRLH/Cathilon Blue C
D-FBLH=1/1 (manufactured by Hodogaya Chemical) 2%owf
Dye bath containing (3 t/l of Glauber's salt as an auxiliary agent. 0.3 t/l of acetic acid
) for 60 minutes at 120°C. As for the clarity of the dyed fabrics, as shown in Table 1, the dyed fabrics according to the examples exhibited a clear deep blue color, whereas the dyed fabrics of the comparative examples were dyed only in a dull blue color.

Examples 4 to 7 In place of sodium acetate used in Example 1,
The same procedure as in Example 1 was conducted except that the organic carboxylic acid metal salt shown in the table was used. The results were as shown in Table 1.

Example 8 3,5-dicarboxybenzenesulfonic acid butyltriphenylphosphonium salt was used in place of the 3,5-dicarboxybenzenesulfonic acid tetra-n-butylphosphonium salt used as the cationic dye dyeing agent in Example 1. The same procedure as in Example 1 was carried out except for the following. The results were as shown in Table 1.

Example 9 Tetra n-3,5-dicarboxybenzenesulfonic acid used as a cationic dye dyeing agent in Example 1
Example 1 was carried out in the same manner as in Example 1, except that 3,5-dicarbomethoxybenzenesulfonic acid tetra-n-butylphosphonium salt was used in place of the butylphosphonium salt, and the timing of its addition was changed to before the start of the transesterification reaction. The results were as shown in Table 1.

Note that even if the sulfonic acid phosphonium salt was added before the transesterification reaction, the reaction rate did not slow down, and the transesterification reaction proceeded smoothly.

Claims (2)

[Claims] (1) The following general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼... (I) In the formula, A is an aromatic group or aliphatic group, X_1 is an ester-forming functional group, X_2 is X_1 The same or different ester-forming functional groups or hydrogen atoms, R_1, R_2, R_3 and R_4 are the same or different groups selected from alkyl groups and aryl groups, and n represents a positive integer. An organic carboxylic acid metal salt of at least one metal selected from alkali metals and alkaline earth metals is added to an acid component ( 0.002 to 0.2 mol% (excluding sulfonate)
A modified polyester composition. (2) The copolymerized amount of the sulfonic acid phosphonium salt is 0.05 to 20 mol% based on the bifunctional carboxylic acid component (excluding the sulfonate) constituting the modified polyester. The modified polyester composition according to item 1.