JPH04337321A - Production of polyester - Google Patents

Abstract

PURPOSE:To obtain polyester fiber having excellent color tone, friction characteristics and a durable soft feeling. CONSTITUTION:After completion of ester interchange reaction, the reaction system is blended with 5-10 pts.wt. higher aliphatic monocarboxylic acid ester having 7-70 acid value such as montanic acid ethylene glycol ester, a Ti compound such as tetrabutyl titanate and a Sb compound such as antimony trioxide as a polycondensation catalyst to produce a polyester.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a method for producing polyester, and more particularly, to a polyester fiber that can form polyester fibers that have excellent color tone and friction properties, as well as durable slimy feel and water repellency. Concerning the manufacturing method.

0002

2. Description of the Related Art Polyester, particularly polyethylene terephthalate, has excellent mechanical and chemical properties and is widely used in fibers, films, and the like. especially,
In the field of fiber applications, many attempts have been made to create fibers that are similar to natural fibers by adding new properties to them while retaining their excellent properties. Among these, many attempts have been made to obtain fibers that have the feel and characteristics of high-quality wool. For example, a method of adding a higher aliphatic monocarboxylic acid ester having an acid value of 5 or less and having 34 to 65 carbon atoms (Japanese Unexamined Patent Publication No. 152816/1983), fine particles with an average particle size of 0.05 to 3 μm and a higher fat Method of adding group monocarboxylic acid esters (JP-A-61-15)
2820), a method of adding natural wax (Japanese Patent Application Laid-Open No. 1982-194249), a method of adding waxes composed of higher aliphatic monocarboxylic acid esters and hydrocarbons (Japanese Patent Application Laid-open No. 1-183518). Public bulletins), etc.

However, the method of adding these additives to the polymer during the polymerization reaction has the disadvantage that the polymerization reaction slows down and productivity decreases. In addition, the color tone of the polymer deteriorates, and it has not yet reached a practical level. Furthermore, after fiber formation, silicon compounds, wax,
A method of attaching a fluorine compound or the like to polyester has also been implemented. However, although these methods do improve the sliminess, they have the disadvantage that the finishing agent comes off during washing or dry cleaning, resulting in poor durability. Furthermore, when used as a film, if the surface is smooth, the films will stick together and will not slip, so it is common practice to mix appropriate particles in to lower the coefficient of friction. However, when this method is used, there are problems in that particle agglomeration frequently occurs and that the number of steps during polymer production increases, making it time-consuming.

0004

[Problems to be Solved by the Invention] The present invention aims to improve the above-mentioned problems and obtain a polymer with excellent reactivity during polymerization, durable sliminess, water repellency, slipperiness, and good color tone. With the goal.

[0005]

[Means for Solving the Problems] The present invention consists of a difunctional carboxylic acid component mainly consisting of a difunctional aromatic carboxylic acid or an ester-forming derivative thereof and a diol component mainly consisting of at least one alkylene glycol. In producing polyester, 5 to 10 parts by weight of at least one higher aliphatic monocarboxylic acid ester having an acid value of 7 or more and 70 or less is added to 100 parts by weight of the difunctional carboxylic acid component.
This is a method for producing polyester, which is characterized in that a Ti compound and an Sb compound are added in parts by weight, and a Ti compound and an Sb compound are used together as a polycondensation reaction catalyst.

The difunctional aromatic carboxylic acid or its ester-forming derivative used in the present invention is mainly terephthalic acid or its lower alkyl ester, but other acid components such as isophthalic acid, phthalic acid, Naphthalene dicarboxylic acid, p-β-oxyethoxybenzoic acid, sebacic acid, adipic acid, succinic acid, oxalic acid, diphenyl-4,4'-dicarboxylic acid, diphenyl ether-4,4'-dicarboxylic acid, 5-sodium sulfoisophthalate Acids, trimellitic acid, lower alkyl or glycol esters thereof, and the like can be used alone or in combination. The proportion of such combined acid components is preferably 30 mol % or less, further 20 mol % or less, particularly 15 mol % or less, based on the total acid components.

[0007]Alkylene glycol is mainly used as the diol component used in the present invention.
Examples of the alkylene glycol include ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, and hexamethylene glycol, among which ethylene glycol and tetramethylene glycol are particularly preferred. In the present invention, such alkylene glycols can be used in combination with each other or with other diols. For example, when ethylene glycol or tetramethylene glycol in a preferred embodiment is used as the main glycol component, other glycol components such as ethylene glycol (when tetramethylene glycol is the main glycol component), propylene glycol, trimethylene glycol, tetramethylene glycol (when ethylene glycol is the main glycol component),
neopentyl glycol, hexamethylene glycol,
One or more of pentamethylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, bisphenol A, and hydroquinone can be used in combination. Such combined diol components are
30 mol% or less, even 20 mol% based on total acid components
Hereinafter, the proportion is particularly preferably 15 mol% or less.

Specific preferred aromatic polyesters include polyethylene terephthalate, polybutylene terephthalate, polyhexylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and polyethylene-1,2-bis(phenoxy)ethane-4,4'.
- dicarboxylate, and copolymerized polyesters such as polyethylene isophthalate/terephthalate, polybutylene terephthalate/isophthalate, polybutylene terephthalate/decane dicarboxylate, and the like. Among these, polyethylene terephthalate and polybutylene terephthalate, which have well-balanced mechanical properties and moldability, are particularly preferred.

[0009] Such polyesters can be synthesized by any method. For example, in the case of polyethylene terephthalate, terephthalic acid and ethylene glycol are usually directly esterified, or an ester-forming derivative of terephthalic acid such as dimethyl terephthalate is transesterified with ethylene glycol, or terephthalic acid and ethylene glycol are transesterified. The first stage reaction involves reacting with ethylene oxide to produce a glycol ester of terephthalic acid 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 higher aliphatic monocarboxylic acid ester used in the present invention must have an acid value of 7 or more and 70 or less. When the acid value of the higher aliphatic monocarboxylic acid ester is less than 7, the effect of improving the slimy feeling is small. That is, if the acid value is too low, the dispersibility in the polyester polymer will be poor and it will easily leave the system during post-processing after dyeing. On the other hand, if the acid value exceeds 70, the polyester polymer will be significantly decomposed, resulting in poor mechanical properties and severe discoloration.

The higher aliphatic monocarboxylic acid ester used in the present invention preferably has 50 to 100 carbon atoms.
The main component is an ester compound, more preferably a compound having 55 to 80 carbon atoms, particularly preferably a compound having 60 to 70 carbon atoms. If the number of carbon atoms in the higher aliphatic monocarboxylic acid ester is less than 50, the effect of improving the slimy feeling derived from the long-chain alkyl group will be reduced, and the proportion of scattering during the high-temperature, high-vacuum polymerization reaction will increase, which is undesirable. . On the other hand, if the number of carbon atoms exceeds 100, the compatibility with polyester will be poor, and not only will the yarn be likely to break during spinning and drawing, but it will also be more likely to be discharged to the outside during processes such as dyeing and heat setting, making it less effective. do not have.

[0012] The higher aliphatic monocarboxylic acid ester is
The acid component is a higher fatty acid with a carbon number of 20 or more, and the carbon number is 20 or more.
Compounds containing the above-mentioned higher alcohols or polyols having 2 or more carbon atoms as the alcohol component are preferred. This higher aliphatic monocarboxylic acid ester has substantially no free hydroxyl groups; for example, when the alcohol component is a diol, a compound in which both hydroxyl groups of the diol react with the higher fatty acid to form an ester is preferred.

Specific examples of such higher aliphatic monocarboxylic acid esters include myricyl cerotate, ceryl cerotate, ethylene glycol montanate, ethylene glycol n-nonacosanoate, ethylene glycol merisinate, and n-pentriacontane. acid ethylene glycol ester, n-dotriacontanoic acid ethylene glycol ester, montanic acid tetramethylene glycol ester, montanic acid glycerin ester, montanic acid sorbitan ester, etc. These may be used alone or in combination of two or more. They may be used in combination. Among these, montanic acid ethylene glycol ester is preferred because it has good compatibility with polyester.

In the present invention, the amount of the higher aliphatic monocarboxylic acid ester is 5 to 10 parts by weight, preferably 5.5 to 8 parts by weight, per 100 parts by weight of the difunctional carboxylic acid component.
Add 5 parts by weight. If the amount of the higher aliphatic monocarboxylic acid ester added is less than 5 parts by weight, no slimy feeling will occur;
On the other hand, when the amount exceeds 10 parts by weight, not only the color tone of the resulting polymer deteriorates, but also the polymerization reactivity becomes significantly inferior.

The higher aliphatic monocarboxylic acid ester can be added at any time until the production of the polyester is completed. For example, whether it is added and mixed into the polyester raw materials, added during the first stage reaction, added between the end of the first stage reaction and the start of the second stage reaction, or added in the second stage. may be added during the reaction. Among these, higher aliphatic monocarboxylic acid esters can be added between the end of the first stage reaction and the start of the second stage reaction because they are well dispersed in polyester and copolymerized easily. preferable.

Furthermore, in the present invention, it is important to use a Ti compound and an Sb compound together as a polycondensation catalyst. The amount of the Ti compound and Sb compound used is 1×10
-3≦Ti≦2×10−2 1×10−2≦Sb≦5×10−2 11×10−3≦Ti+Sb≦51×10−3 (in the formula,
Ti and Sb each represent a Ti compound and an Sb compound,
The numerical value indicates the molar percentage of the compound added to the difunctional carboxylic acid component. ) is preferable.

[0017] The amount of Ti compound added is 1 x 10-3 mol%
If it is less than 2×1, there is no effect of promoting the polymerization reaction;
If it exceeds 0-2 mol %, the thermal stability of the polymer will deteriorate and it will be colored yellow, which is not preferable. Furthermore, if the amount of the Sb compound added is less than 1 x 10-2 mol%, the effect of promoting the polymerization reaction will be lost, which is not preferable, whereas if it exceeds 5 x 10-2 mol%, the effect of accelerating the polymerization rate will be saturated. Not only is it ineffective, but it also becomes a dark hue, which is not desirable. Furthermore, if the total amount of Ti compound and Sb compound is less than 11 x 10-3 mol%, it is not sufficient as a catalyst and the polymerization reaction will be slow, whereas if it exceeds 51 x 10-3 mol%, the polymerization reaction will be slow. This is not preferred because the hue of the polymer deteriorates.

As mentioned above, in the present invention, it is important to use specific amounts of the Ti compound and the Sb compound together. This not only affects the polymerization rate and color of the polymer, but is also necessary to maintain a durable slimy feel. In other words, during the polycondensation reaction, copolymerization of the higher aliphatic monocarboxylic acid ester into the polyester polymer proceeds rapidly, especially at the initial stage, and the added higher aliphatic monocarboxylic acid ester is less likely to scatter out of the system, resulting in improved durability. Not only can a certain slimy feeling be imparted, but also it is possible to prevent clogging of the vacuum suction device with higher aliphatic monocarboxylic acid esters. Moreover, by doing so, it is possible to achieve not only a slimy feeling but also excellent water repellency and slip characteristics with excellent durability.

The Ti compound used as a polycondensation catalyst in the present invention may be any Ti compound having polycondensation catalytic ability, and has the general formula Xm Ti(OR)l [wherein, X is a halogen atom or hydrogen atom, is an alkyl group (having 1 to 6 carbon atoms), and m and l are 0 or a positive integer (at least one of m and l is a positive integer). ](Me)n TiF6 (In the formula, Me is a metal atom or NH4, and n is a positive integer.) (Ti) p (OOCR')q [In the formula, R' may contain a carboxyl group. An alkyl group (having 1 to 6 carbon atoms), an aryl group, a cycloalkyl group, an aralkyl group (having 6 to 12 carbon atoms), p and q are positive integers. ] can be mentioned.

Specifically, titanium alkoxides such as titanium tetramethoxide, titanium tetrapropoxide, titanium tetrabutoxide, titanium oxyisopropoxide, and titanium oxybutoxide, and combinations of such titanium alkoxides with trimellitic acid, hemimellitic acid, and pyromellitic acid are used. Reaction products with aromatic polycarboxylic acids such as acids or their acid anhydrides, titanium tetrachloride, lithium salts of fluorotitanic acid,
Potassium salts, magnesium salts, titanium oxalate, titanium acetate and the like, as well as hydrolysates or derivatives thereof, can be mentioned. Among these, titanium alkoxide and a reaction product of titanium alkoxide and an aromatic polycarboxylic acid or an acid anhydride thereof are preferred. These Ti
Compounds: Two or more types may be used in combination.

As the Sb compound used in combination with the Ti compound, antimony oxides represented by antimony trioxide, antimony tetraoxide, and antimony pentaoxide, and antimony halogens represented by antimony trichloride and antimony pentachloride are used. Antimony carboxylates such as antimony compounds and antimony carboxylates typified by antimony acetate. Among them, antimony trioxide is particularly preferred.

In the present invention, additives such as stabilizers, matting agents, colorants, lubricants, flame retardants, ultraviolet absorbers, and antistatic agents may be added as necessary. In particular, it is preferable to add stabilizers that are conventionally known and used in order to further enhance the thermal stability of polyester. Examples of the stabilizer include phosphoric acid, phosphorous acid, phosphinic acid, phosphorus compounds such as esters thereof, and hindered phenol compounds. In addition, inert fine particles may be contained in the polyester if necessary. As a method for incorporating inert fine particles into polyester, any of the conventionally known external addition method and internal precipitation method can be employed. When inert fine particles are added, preferred examples of the fine particles include silicon oxide, calcium carbonate, titanium oxide, kaolin, clay, and calcium terephthalate.

The polyester thus obtained has an intrinsic viscosity (measured in orthochlorophenol at 35° C.) of 0.
It is preferably 4 or more, more preferably 0.5 or more.

[Function] In the present invention, by using a specific catalyst and a higher aliphatic monocarboxylic acid ester having a specific acid value, the reactivity during polymerization is improved. This was done based on the knowledge that a polymer with good color tone that has water repellency and slip properties can be obtained.

[0024]

[Examples] The present invention will be explained in more detail below with reference to Examples. Note that parts in the examples mean parts by weight. Moreover, each characteristic value was measured by the following method. (1) Intrinsic viscosity It was determined from the solution viscosity measured at 35°C after dissolving a polymer in orthochlorophenol. (2) Coefficient of dynamic friction The coefficient of dynamic friction between films according to ASTM-D-1894B is substituted for evaluation of the sliding property. (3) Water repellency (U) According to method A of JIS L1018 water repellency measurement, 27°C
The wetting characteristics when water is sprayed are expressed as a numerical value from 100 (no wetting) to 0 (completely wetting). (4) Slimy feel (N) The sample to be evaluated was knitted into a tube, and 15 panelists touched it with their hands to conduct a sensory test. If 7 or more panelists found the product to be slimy, it was rated as ○, if 6 to 5 panelists found it to be slimy, it was rated as △, and if not, it was rated as ×.

Examples 1 to 6, Comparative Examples 1 to 6 (Production of polyester) 100 parts of dimethyl terephthalate, 58 parts of ethylene glycol, and 0.08 parts of manganese acetate as a transesterification catalyst were charged into a reactor, and the mixture was heated inside the reactor under stirring. The transesterification reaction was carried out while distilling off methanol until the temperature reached 240°C. After the transesterification reaction was completed, 0.097 part of trimethyl phosphate was added, and then the montanic acid glycol ester listed in Table 1 was added. After that, antimony trioxide and titanium trimellitate listed in Table 1 were added as polycondensation catalysts, and the reaction product was heated,
Finally, polycondensation was carried out under high vacuum conditions at 280°C. After the reaction was completed, the polymer was made into chips by a conventional method.

The obtained chips were dried by a conventional method, melt-extruded to form a film, and then stretched at 90° C. in the longitudinal direction at a stretching ratio of 3.
．． The film was biaxially stretched 5 times and at a stretching ratio of 4.0 times in the transverse direction, and further heat-set at 230° C. for 20 seconds to obtain a biaxially stretched film with a thickness of 50 μm. The coefficient of dynamic friction of the obtained film was used to evaluate the sliding properties. The results are shown in Table 1. In addition, the obtained chips were dried by a conventional method, and spun at 285°C using a spinneret with 24 circular spinning holes with a hole diameter of 0.3 mm.
Melt-spun with
A multifilament of denier/24 filament was obtained. The obtained multifilament was knitted into a knitted fabric, scoured by a conventional method, preset at 160° C. for 1 minute, and then evaluated for water repellency (U) and slimy feel (N).

[0027] Furthermore, using a household washing machine, a 0.2% aqueous solution of Neopex 2P (manufactured by Kao Soap Co., Ltd.)
Wash at 0°C for 10 minutes, then at 40°C for 5 minutes,
Next, after washing with overflow water for 15 minutes, it was dehydrated and dried at 80° C. for 30 minutes. This washing-drying process is repeated 30 and 50 times, and the water repellency after presetting (U
), and the slimy feeling (N) was evaluated. The results are shown in Table 1.

[0028]

[Table 1]

Examples 7 to 9 In place of the montanic acid glycol ester used in Example 1, the additives shown in Table 2 were added to obtain polymers. Table 2 shows the quality of the obtained polymer and the evaluation results of film formation and spinning.

[0030]

[Table 2]

[0031]

Effects of the Invention According to the present invention, since the polymer contains a higher aliphatic monocarboxylic acid ester, it has good sliminess, water repellency and friction properties, and the modifier present on the surface is Even if it falls off during washing or the like, it is immediately replenished from inside the polymer by heat treatment such as ironing, making it possible to obtain a polyester that can maintain the above-mentioned properties of sustainability and durability. In addition, by using a Ti compound and an Sb compound together as a polymerization catalyst, the reaction between polyester and higher aliphatic monocarboxylic acid ester proceeds rapidly in the early stage of the polycondensation reaction, and a specific amount of higher aliphatic groups are copolymerized into polyester. Therefore, it can be assumed that a durable slimy feel can be maintained, which is different from the conventional method in which additives that improve the slimy feeling are simply added and mixed into polyester.

Claims (3)

[Claims] Claim 1: In producing a polyester consisting of a difunctional carboxylic acid component mainly consisting of a difunctional aromatic carboxylic acid or an ester-forming derivative thereof and a diol component mainly consisting of at least one alkylene glycol, the acid value 5 to 10 parts by weight of at least one higher aliphatic monocarboxylic acid ester having a polycondensation reaction of 7 or more and 70 or less is added to 100 parts by weight of the difunctional carboxylic acid component, and a Ti compound and an Sb compound are used as polycondensation reaction catalysts. A method for producing polyester, characterized in that it is used in combination. 2. The method for producing polyester according to claim 1, wherein the added amounts of the Ti compound and the Sb compound satisfy the following formula. 1×10-3≦Ti≦2×10-2 1×10-2≦Sb≦5×10-2 11×10-3≦Ti+Sb≦51×10-3 (in the formula,
Ti and Sb each represent a Ti compound and an Sb compound,
The numerical value indicates the molar percentage of the compound added to the difunctional carboxylic acid component. ) 3. The Ti compound is at least one compound selected from the group of tetrabutyl titanate, titanium acetate, and titanium trimellitate, and the Sb compound is at least one compound selected from the group of antimony trioxide and antimony acetate. The method for producing a polyester according to claim 1, which is a compound of