JP2001048965A - Polyester composition including bisoxazolin and production of polyester of high polymerization degree using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyester composition that comprises a polyester polymer and a bisoxazolin and can produce molded products of an increased degree of polymerization by using a conventional polyester molding machine. SOLUTION: The objective polyester composition comprises (A) a polyester polymer bearing at least one kind of the main molecular recurring units selected from ethylene terephthalate, ethylene naphthalate, propylene terephthalate and the like, and (B) a bisoxazolin of the formula (R1-R8 are each H or a monovalent organic acid; X is a divalent organic acid; n is 0 or 1), [for example, 2,2'-(2- oxzoline) or the like]. This composition satisfies the following requirements: (1) the intrinsic viscosity thereof is 0.40-1.00; (2) the content of the functional group of the unreacted oxazolin is 10-1,400 equivalent/ton and (3) the melting point of the composition after addition of the bisoxazolin is more than 4 deg.C lower than that before the addition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a bisoxazoline compound-containing polyester composition and a method for producing a polyester having a high degree of polymerization using the same.

[0002]

2. Description of the Related Art Polyethylene terephthalate (hereinafter P)
ET), polytrimethylene terephthalate (hereinafter sometimes abbreviated as PTT), polybutylene terephthalate (hereinafter sometimes abbreviated as PBT), polyethylene naphthalate (hereinafter abbreviated as PEN)
Polyester) (mainly abbreviated as PTQ), polybutylene naphthalate (hereinafter sometimes abbreviated as PBN) and the like. Due to their excellent properties such as properties, mechanical properties, solvent resistance, light resistance, and dimensional stability, they have been widely used as fibers, films, bottles, and various molded articles as engineering plastics.

Among the physical properties of these polyester products, the mechanical properties, in particular, depend largely on the degree of polymerization of the polymer, that is, the intrinsic viscosity, and various methods for producing polyesters having a high degree of polymerization have been studied. For example, increasing the degree of polymerization by solid-phase polymerization is still widely used at present.

[0004] This solid-phase polymerization can obtain a polyester having a desired degree of polymerization by controlling the time and temperature of the solid-phase polymerization, and is a very useful means.
The solid phase polymerization time is usually several times to several tens times longer than the time required for melt polymerization, the productivity is low, and when the degree of polymerization of low melting point and low crystalline polyester is to be increased, solidification is required. There is also a problem that during the phase polymerization reaction, fusion between the polyester chips or between the polyester chips and the reaction vessel wall occurs.

In order to solve such problems, for example, Japanese Patent Application Laid-Open No. 55-145,734 discloses a method for producing a high polymerization degree polyester by melt-reacting a bisoxazoline compound with a polyester polymer. This method is a very useful method in which a high polymerization degree polyester can be obtained only by adding a very small amount of a bisoxazoline compound.However, the reactivity of the bisoxazoline compound used is high, and it is effective in a small amount. Therefore, there is also a problem that it is difficult to control the addition method.

In order to solve such a problem, Japanese Patent Laid-Open Publication No.
No. 71419 discloses a method in which a bisoxazoline compound is dissolved in an organic solvent such as methylene chloride or chloroform and added. By using this method, by controlling the concentration of the bisoxazoline compound solution to be prepared and the rate of addition during the melt reaction with the polyester, it is possible to accurately react the polyester with the bisoxazoline compound to produce a high polymerization degree polyester. You can,
A facility for mixing the bisoxazoline compound solution and the polyester is necessary, and furthermore, it is unfavorable in terms of safety, worker's health, and environment because it is volatilized later using an organic solvent. Had also.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a high-polymerized polyester without solid-state polymerization, which can provide a polyester product having a high polymerization degree by using a conventional polyester molding machine. It is an object of the present invention to provide a possible polyester composition. Still another object of the present invention is to provide a method for producing a high polymerization degree polyester using the above polyester composition.

[0008]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems of the prior art, and have completed the present invention.

That is, an object of the present invention is that the main repeating unit is at least one type of repeating unit selected from the group consisting of ethylene terephthalate, ethylene naphthalate, propylene terephthalate, propylene naphthalate, butylene terephthalate and butylene naphthalate. To be achieved by a bisoxazoline compound-containing polyester composition which comprises a polyester polymer and a bisoxazoline compound represented by the following general formula (1) and simultaneously satisfies the following requirements (I) to (III): Can be. (I) The intrinsic viscosity is 0.40 to 1.00. (II) The amount of unreacted oxazoline functional groups in the polyester composition is 10 to 1400 eq / ton. (III) The melting point of the composition after the addition of the bisoxazoline compound is 4 ° C. or lower than the melting point of the polymer before the addition of the compound.

[0010]

Embedded image

Another object of the present invention is to provide a bisoxazoline compound-containing polyester composition according to claim 1 having a terminal carboxyl group content of 5 to 80 eq / ton and an intrinsic viscosity of 0.30 to 0.90. A polyester polymer is melt-kneaded, and the amount of unreacted oxazoline functional groups in the kneaded polyester composition is 10 eq / ton.
This is achieved by a method for producing a polyester having a high degree of polymerization, so as to be less than.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. In the present invention, a polyester having a main repeating unit as at least one type of repeating unit selected from the group consisting of ethylene terephthalate, ethylene naphthalate, propylene terephthalate, propylene naphthalate, butylene terephthalate, and butylene naphthalate is a main dicarboxylic acid. Polyethylene terephthalate and a copolymer thereof, wherein the acid component is terephthalic acid and / or naphthalenedicarboxylic acid, and the main glycol component is at least one glycol component selected from the group consisting of ethylene glycol, propylene glycol and butylene glycol. Polyethylene naphthalate and its copolymer, polypropylene terephthalate and its copolymer, polypropylene naphthalate and its copolymer, poly Chi terephthalate and its copolymers, polybutylene naphthalate and copolymers thereof. In addition, as naphthalenedicarboxylic acid, for example, 2,6-naphthalenedicarboxylic acid component, 2,2
Examples thereof include a 7-naphthalenedicarboxylic acid component and a 1,5-naphthalenedicarboxylic acid component, and a 2,6-naphthalenedicarboxylic acid component is preferable.

Here, the term "main" in the present invention means that the component accounts for 80 mol% based on all the reference components.

The polyester polymer used before the addition of the above bisoxazoline compound is:
It is preferable that the terminal carboxyl group content is 30 eq / ton or less. When it is within the above range, the amount of the unreacted oxazoline functional group can be easily set in the range described later, which is preferable from the viewpoint of cost.

In addition, the molecular weight of the polyester polymer in the bisoxazoline compound-containing polyester composition is too high, and the melt viscosity is too high when subsequently pelletizing the composition or melt-kneading with the polyester. The terminal carboxyl group content is 25 eq / ton.
It is more preferably at most 20 eq / ton, particularly preferably at most 20 eq / ton.

Further, the intrinsic viscosity of the polyester polymer used in the present invention is preferably in the range of 0.20 to 0.80. When it is in this range, the melt viscosity becomes moderate, and the melt viscosity of the finally obtained bisoxazoline compound-containing polyester composition becomes easy to handle. The intrinsic viscosity of the polyester is 0.30
More preferably, it is in the range of 0.70, and 0.40
A range of .about.0.65 is particularly preferred.

The bisoxazoline compound used in the present invention must be represented by the following general formula (1).

[0018]

Embedded image

The organic groups represented by R _{1 to} R ₈ are preferably an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, a cycloalkyl group having 5 to 12 carbon atoms, or a C ₈ to C ₈ organic group. And 20 aralkyl groups. It is most preferred that all of R _{1 to} R ₈ are hydrogen atoms. X in the formula is a divalent organic group, for example, an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, an arylene group having 6 to 12 carbon atoms, and a carbon atom having 5 to 5 carbon atoms.
And a cycloalkylene group having 12 carbon atoms and an aralkylene group having 8 to 20 carbon atoms.

More specifically, examples of the alkylene group include methylene, ethylene, propylene, butylene, pentylene, hexamethylene, octamethylene, nonamethylene,
Examples include decamethylene and dimethylmethylene. Examples of the arylene group include phenylene, naphthylene, diphenylene, -Ph-R'-Ph- (where R '
, - - -O is CO -, - S -, - SO 2 -, - CH 2 -,
—CH ₂ CH ₂ —, —C (CH ₃ ) ₂ — and the like;
Represents a phenylene group. ), And the cycloalkylene group includes cyclohexylene.

In the formula, n is 0 or 1. Here, n is most preferably 0, and when n is 1, X is preferably an arylene group. Such bisoxazoline compounds include 2,2′-bis (2-
Oxazoline), 2,2'-bis (4-methyl-2-oxazoline), 2,2'-bis (4,4-dimethyl-2
-Oxazoline), 2,2'-bis (4-ethyl-2-
Oxazoline), 2,2'-bis (4,4'-diethyl-2-oxazoline), 2,2'-bis (4-propyl-2-oxazoline), 2,2'-bis (4-butyl-
2-oxazoline), 2,2'-bis (4-hexyl-
2-oxazoline), 2,2'-bis (4-phenyl-
2-oxazoline), 2,2'-bis (4-cyclohexyl-2-oxazoline), 2,2'-bis (4-benzyl-2-oxazoline), 2,2'-p-phenylenebis (2-oxazoline) ), 2,2'-m-phenylenebis (2-oxazoline), 2,2'-o-phenylenebis (2-oxazoline), 2,2'-p-phenylenebis (4-methyl-2-oxazoline) , 2,2'-p
-Phenylenebis (4,4-dimethyl-2-oxazoline), 2,2′-m-phenylenebis (4-methyl-2
-Oxazoline), 2,2'-m-phenylenebis (4,4-dimethyl-2-oxazoline), 2,2'-
Ethylenebis (2-oxazoline), 2,2′-tetramethylenebis (2-oxazoline), 2,2′-hexamethylenebis (2-oxazoline), 2,2′-octamethylenebis (2-oxazoline), 2,2'-decamethylenebis (2-oxazoline), 2,2'-ethylenebis (4-methyl-2-oxazoline), 2,2'-tetramethylenebis (4,4-dimethyl-2-oxazoline) , 2,2'-9,9'-diphenoxyethanebis (2-oxazoline), 2,2'-cyclohexylenebis (2-oxazoline), 2,2'-diphenylenebis (2-oxazoline) and the like. Among them, 2,2′-bis (2-oxazoline) represented by the following structural formula (2) is most preferable from the viewpoint of reactivity with polyester. Further, the above-mentioned bisoxazoline compounds may be used alone or in combination of two or more as long as the object of the present invention is achieved.

[0022]

Embedded image

In the present invention, the amount of the bisoxazoline compound to be added to the polyester polymer may be arbitrarily set as long as the intrinsic viscosity, unreacted oxazoline functional group amount, and melting point of the bisoxazoline compound-containing polyester composition described later are satisfied. Can be done, but among them 3.
It is preferable to set it in the range of 0 to 30% by weight. When the addition amount is within this range, a sufficient amount of unreacted oxazoline functional group can be secured, and the loss of the bisoxazoline compound due to sublimation during use can be reduced. The addition amount is more preferably in the range of 0.3 to 7% by weight, particularly preferably in the range of 0.5 to 5% by weight.

The intrinsic viscosity of the bisoxazoline compound-containing polyester composition of the present invention must be in the range of 0.40 to 1.00. If the intrinsic viscosity is less than 0.40, the melt viscosity is too low, making it difficult to handle. on the other hand,
If the intrinsic viscosity exceeds 1.00, the melt viscosity is too high,
Melt kneading becomes difficult during production of a high polymerization degree polyester described below. The intrinsic viscosity of the polyester composition is 0.45 to
The range of 0.90 is preferable, and the range of 0.50 to 0.80 is more preferable.

The amount of unreacted oxazoline functional groups contained in the bisoxazoline compound-containing polyester composition of the present invention must be 10 to 1400 eq / ton. Here, the amount of the unreacted oxazoline functional group is an equivalent of the unreacted oxazoline functional group contained in a certain amount of the polyester composition. For example, when one equivalent of the bisoxazoline compound remains, the amount of the oxazoline functional group is Expressed as two equivalents.

When the amount of the functional group is less than 10 eq / ton, the amount of the unreacted bisoxazoline compound is too small, so that it is difficult to produce a high polymerization degree polyester described later. On the other hand, if it exceeds 1400 eq / ton, there are too many unreacted bisoxazoline compounds, which causes problems such as sublimation in large quantities during use.

The amount of the unreacted oxazoline functional group is from 20 to
It is preferably in the range of 1000 eq / ton, and 50
The range of -700 eq / ton is more preferable.

In the present invention, it is necessary that the melting point of the composition after the addition of the bisoxazoline compound is lower by at least 4 ° C. than the melting point of the polymer before the addition of the bisoxazoline compound. If the melting point difference is less than 4 ° C., the amount of unreacted bisoxazoline compound is small, and the effect as a master polyester cannot be sufficiently exhibited. The melting point difference is preferably lower by 5 to 20C, more preferably lower by 6 to 15C.

The method of adding the bisoxazoline compound to the polyester at the time of producing the bisoxazoline master polyester composition of the present invention is not particularly limited as long as a solvent is not used. For example, the polyester is melted with an extruder or the like. A method in which the powder of the oxazoline compound is supplied from a side feeder, a method in which the polyester is melted in a reactor such as a polymerization reactor, or a method in which the bisoxazoline compound is added at the end of the polyester polycondensation reaction and mixed under melt stirring, before melting. A method in which a bisoxazoline compound powder is sprayed on the recovered polyester and then melt-mixed in an extruder or a reactor is used.

Among these, a method of melting the polyester with an extruder or the like, adding a powder of a bisoxazoline compound, and thereafter pelletizing is particularly preferably performed.

In the production method of the present invention, the polyester polymer used for melt-kneading with the bisoxazoline compound-containing polyester composition when producing a high polymerization degree polyester has a terminal carboxyl group content of 5 to 80 eq /.
must be in the range of ton.

When the amount of terminal carboxyl groups of the polyester polymer is less than 5 eq / ton, the effect of increasing the degree of polymerization received when melt-kneaded with the bisoxazoline compound-containing polyester composition is low. On the other hand, 80 eq / ton
If the ratio exceeds the above range, the degree of molecular weight reduction that occurs during melt-kneading is too high, so that a high polymerization degree polyester cannot be produced efficiently. The terminal carboxyl group content is 8 to 70 e
q / ton, preferably 10-60 e
The range of q / ton is more preferable.

Further, it is necessary to have the above-mentioned amount of terminal carboxyl groups and to have an intrinsic viscosity in a range of 0.3 to 0.9. When the intrinsic viscosity of the polyester is less than 0.3, the molecular weight of the polyester itself is too low, and the finally obtained polyester has a low molecular weight or low heat resistance. On the other hand, if it exceeds 0.9, the melt viscosity of the finally obtained high-polymerization degree polyester is too high, and the moldability becomes poor. The intrinsic viscosity of the polyester is 0.4
The range is preferably from 0.85 to 0.85, and more preferably from 0.45 to 0.8.

In the production method of the present invention, the polyester composition containing the bisoxazoline compound of the present invention is melt-kneaded. Specific examples of the polyester polymer include polyethylene terephthalate-based polymers, polyethylene naphthalate-based polymers, and polybutylene terephthalate. Polymer and polybutylene naphthalate polymer.

The bisoxazoline compound-containing polyester composition is melt-kneaded with the above-mentioned polyester polymer. The polyethylene terephthalate-based polymer is composed mainly of polyethylene terephthalate, and the polyethylene naphthalate-based polymer is composed of polyethylene naphthalate. Polyester composition mainly composed of polypropylene terephthalate-based polymer, polyester composition composed mainly of polypropylene terephthalate, polypropylene naphthalate-based polymer composed of polyester composed mainly of polypropylene naphthalate, and polybutylene terephthalate-based polymer composed of poly Polybutylene terephthalate-based polyester composition and polybutylene naphthalate-based polymer mainly contain polybutylene naphthalate The use of polyester compositions respectively, from the viewpoint of kneading degree at the time of melting and kneading.

The method of melt-kneading the bisoxazoline compound-containing polyester composition and the above-mentioned polyester polymer is not particularly limited. For example, two kinds of polymer chips are pre-blended and then melted by a twin-screw extruder or the like. A method of sufficiently kneading with a kneader, a method in which a polyester polymer is melted in a melting tank in advance and then a bisoxazoline-containing polyester composition is added, and the polyester polymer is melted in a twin-screw extruder, and then from a side feeder. Any method of adding a bisoxazoline-containing polyester composition can be employed, but a method in which two types of polymer chips are preliminarily blended from the viewpoint of equipment is preferable.

The melting temperature during the melt-kneading is not particularly limited, either, but is not less than the melting point of the polyester polymer.
It may be carried out at a temperature of 0 ° C. or less, more preferably from the melting point of the polyester polymer to 300 ° C. or less.

As for the melting and kneading time, the residence time is set to about 5 to 30 minutes when the kneading is performed in a batch mode, and the average retention time is set to about 5 to 20 minutes when the kneading is performed in a continuous mode. I just need.

Further, the melt kneading is performed under pressure, under normal pressure,
Although it can be carried out under any reduced pressure, it is preferably under normal pressure from the viewpoint of equipment cost.

In the process for producing a polyester having a high degree of polymerization of the present invention, a lubricant, a pigment, a dye, an antioxidant, Additives such as a phase polymerization accelerator, a fluorescent whitening agent, an antistatic agent, an antibacterial agent, an ultraviolet absorber, a light stabilizer, a heat stabilizer, a light-shielding agent, and a matting agent can be added.

[0041]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited by these examples. Each value in the examples was obtained by the following method. 1) Intrinsic viscosity: measured in orthochlorophenol at 35 ° C.

2) Carboxyl terminal group amount: Makrom
ol. chem. , 26, 226 (1958).

3) Unreacted oxazoline functional group content: A
ppl. Polym. Sci. , Vol. 33,306
9 (1987).

4) Residual rate of unreacted oxazoline: The value obtained by dividing the amount of the oxazoline functional group determined by the above-mentioned measuring method 3) by the amount of the oxazoline functional group calculated from the amount of the added bisoxazoline compound was expressed as a percentage.

5) Melting point: "DSC2" manufactured by TA Instruments in accordance with the method described in JIS 7121.
010 Differential Scanning
The melting peak temperature was measured using a "Colorimeter".

[Examples 1 and 2] Terminal carboxyl group content 1
After drying a polyethylene terephthalate chip having a temperature of 0 eq / ton, an intrinsic viscosity of 0.50 and a melting point of 258 ° C. in a hot air dryer at 160 ° C. for 4 hours, it was melted at 285 ° C. using a biaxial extruder. Using a quantitative side feeder at a speed at which the amount of addition is the amount shown in Table 1,
Melt kneading was performed by adding 2′-bis (2-oxazoline) so that the average residence time was about 10 minutes, and chips were formed according to a conventional method. Table 1 shows the characteristics of the obtained chip.

[Examples 3 and 4] In Example 1, as a polyethylene terephthalate chip, the amount of terminal carboxyl groups was 20 eq / ton, the intrinsic viscosity was 0.60, and the melting point was 2
The same operation was performed except that a polyethylene terephthalate chip at 57 ° C. was used and the amount of 2,2′-bis (2-oxazoline) added was as shown in Table 1.
Table 1 shows the results.

Example 5 Dimethyl terephthalate 100
Parts of ethylene glycol and 67 parts by weight of ethylene glycol were subjected to a transesterification reaction using 0.032 parts by weight of manganese acetate tetrahydrate as a transesterification catalyst, and 0.019 parts by weight of trimethyl phosphate was added. The transesterification reaction was substantially terminated.

Then, 0.042 parts by weight of antimony trioxide was added, and subsequently a polycondensation reaction was carried out at 280 ° C. under a high vacuum by a conventional method. After sampling a small amount at the end of the polycondensation reaction, 1.0 part by weight of 2,2′-bis (2-oxazoline) is added under a nitrogen atmosphere while the polymer is melted in the polycondensation reaction vessel as it is, and the polymerization is continued for 10 minutes. After stirring under pressure, chips were formed by a conventional method. Table 1 shows the characteristics of the obtained chip. The amount of terminal carboxyl groups of the polymer sampled at the end of the polycondensation reaction was 16 eq / ton,
The intrinsic viscosity was 0.57 and the melting point was 255 ° C.

Examples 6 and 7: Terminal carboxyl group content 1
After drying a polyethylene naphthalate chip having a viscosity of 7 eq / ton, an intrinsic viscosity of 0.58 and a melting point of 267 ° C. with a hot air drier at 180 ° C. for 3 hours, it is melted at 295 ° C. using a biaxial extruder and quantified. Using a side feeder, 2,2′-bis (2-oxazoline) was added at a rate shown in Table 1 and melt-kneaded so that the average residence time was about 10 minutes. It has become. Table 1 shows the characteristics of the obtained chip.

Examples 8 to 9: Terminal carboxyl group content 2
After drying a polybutylene terephthalate chip having 5 eq / ton, an intrinsic viscosity of 0.62, and a melting point of 221 ° C. in a hot air drier at 130 ° C. for 5 hours, it was melted at 265 ° C. using a biaxial extruder and quantified. Using a side feeder, 2,2′-bis (2-oxazoline) was added at a rate shown in Table 1, melt-kneaded so that the average residence time was about 10 minutes, and formed into chips according to a conventional method. . Table 1 shows the characteristics of the obtained chip.

Example 10 Terminal carboxyl group content 25
eq / ton, a polybutylene naphthalate chip having an intrinsic viscosity of 0.60 and a melting point of 243 ° C. were dried with a hot air drier at 150 ° C. × 5 hours, and then melted at 285 ° C. using a biaxial extruder. Using a quantitative side feeder, 2,2′-bis (2-oxazoline) was added so that the addition amount was 2.0% by weight, melt-kneaded for about 10 minutes, and formed into chips according to a conventional method. Table 1 shows the characteristics of the obtained chip.

[Comparative Example 1] In Example 1, a polyethylene terephthalate chip was prepared using a terminal carboxy group content of 50 eq / ton, an intrinsic viscosity of 0.65, and a melting point of 258 ° C.
The same operation was performed except that the polyethylene terephthalate chip was used, but the melt viscosity of the polymer was too high to form a chip.

[Comparative Example 2] In Example 1, a polyethylene terephthalate chip was prepared using a terminal carboxy group content of 10 eq / ton, an intrinsic viscosity of 1.00, and a melting point of 258 ° C.
The same operation was performed except that the solid-state polymerized polyethylene terephthalate chip was used, and the drying step with a hot air drier was omitted, but the melt viscosity of the polymer was too high to be formed into chips. .

[Comparative Example 3] In Example 1, 2, 2 '
The same operation was performed except that the amount of -bis (2-oxazoline) added was 35% by weight to obtain chips. The characteristics of the obtained chip are shown in Table 1, but the added bisoxazoline sublimated in a large amount, the handling property was poor, and the cost was not favorable.

[Comparative Example 4] In Example 3, 2, 2 '
The same operation was carried out except that the amount of -bis (2-oxazoline) was adjusted to 1.5% by weight to obtain chips. Table 1 shows the characteristics of the obtained chip.

Comparative Example 5 The same operation as in Example 7 was carried out except that a polyethylene naphthalate chip having a terminal carboxyl group content of 55 eq / ton, an intrinsic viscosity of 0.60 and a melting point of 267 ° C. was used as the polyethylene naphthalate chip. However, the melt viscosity of the polymer was too high to form chips.

[Comparative Example 6] In Example 9, a polybutylene terephthalate chip was prepared using a terminal carboxyl group content of 60 eq / ton, an intrinsic viscosity of 0.70, and a melting point of 221 ° C.
The same operation was performed except that the polybutylene terephthalate chip was used, but the melt viscosity of the polymer was too high to form a chip.

[0059]

[Table 1]

[Example 11] The bisoxazoline compound-containing polyester chip obtained by the operation of Example 1, a terminal carboxyl group content of 30 eq / ton and an intrinsic viscosity of 0.6
2. Polyethylene terephthalate chips having a melting point of 258 ° C. were chip-blended at a ratio shown in Table 2, and then, using a twin-screw extruder, at 290 ° C. and an average residence time of about 10
Minutes, and the resulting polymer was formed into chips by a conventional method. Table 2 shows the properties of the obtained polymer.

Examples 12 to 13 The same operation as in Example 11 was carried out except that the composition obtained in Example 2 was used as the bisoxazoline compound-containing polyester composition. Table 2 shows the properties of the obtained polymer.

Example 14 The same operation as in Example 11 was carried out except that the composition obtained in Example 3 was used as the bisoxazoline compound-containing polyester composition. Table 2 shows the properties of the obtained polymer.

Example 15 The same operation as in Example 11 was carried out except that the composition obtained in Example 4 was used as the bisoxazoline compound-containing polyester composition. Table 2 shows the properties of the obtained polymer.

Example 16 The same operation as in Example 11 was carried out except that the composition obtained in Example 5 was used as the bisoxazoline compound-containing polyester composition. Table 2 shows the properties of the obtained polymer.

Example 17 A chip of a bisoxazoline compound-containing polyester composition obtained by the procedure of Example 6 and a polyethylene naphthalate chip having a terminal carboxyl group content of 33 eq / ton, an intrinsic viscosity of 0.60 and a melting point of 267 ° C. were shown. The mixture was dry-blended in the amount shown in No. 2 and melt-kneaded using a biaxial extruder at 300 ° C. so that the average residence time was about 10 minutes. The molten polymer was formed into chips by a conventional method. Table 2 shows the properties of the obtained polymer.

Example 18 The same operation as in Example 17 was carried out except that the bisoxazoline compound-containing polyester composition chip obtained by the operation of Example 7 was used as the bisoxazoline compound-containing polyester composition chip. went. Table 2 shows the properties of the obtained polymer.

Example 19 Table 2 shows a bisoxazoline compound-containing polyester chip obtained by the procedure of Example 8 and a polybutylene terephthalate chip having a terminal carboxyl group of 35 eq / ton, an intrinsic viscosity of 0.70 and a melting point of 221 ° C. At 260 ° C. using a twin-screw extruder at an average residence time of about 10
Minutes, and the molten polymer was formed into chips by a conventional method. Table 2 shows the properties of the obtained polymer.

Example 20 The same operation as in Example 19 was performed except that the bisoxazoline compound-containing polyester composition chip obtained by the operation of Example 9 was used as the bisoxazoline compound-containing polyester composition chip. went. Table 2 shows the properties of the obtained polymer.

[Example 21] A chip of the bisoxazoline compound-containing polyester composition obtained by the operation of Example 10 and a polybutylene naphthalate chip having a terminal carboxyl group of 30 eq / ton, an intrinsic viscosity of 0.75 and a melting point of 243 ° C were shown. The mixture was chip-blended at the ratio shown in Fig. 2, using a twin-screw extruder at 270 ° C, and the average residence time was about 10
Minutes, and the molten polymer was formed into chips by a conventional method. Table 2 shows the properties of the obtained polymer.

Comparative Example 7 The same operation as in Example 11 was carried out except that the bisoxazoline-containing polyester composition chip obtained by the operation of Comparative Example 3 was used as the bisoxazoline compound-containing polyester composition chip. Was. Table 2 shows the properties of the obtained polymer.

Comparative Example 8 The same operation as in Example 11 was performed except that the bisoxazoline-containing polyester composition chip obtained by the operation of Comparative Example 4 was used as the bisoxazoline compound-containing polyester composition chip. Was. Table 2 shows the properties of the obtained polymer.

[0072]

[Table 2]

As is clear from Tables 1 and 2, when the bisoxazoline master polyester composition of the present invention is used, the degree of polymerization of the polyester polymer can be easily increased.

[0074]

According to the present invention, in a method for producing a high polymerization degree polyester without involving solid phase polymerization, it is possible to obtain a polyester polymerization product having a high polymerization degree using a conventional polyester molding machine. It is possible to provide a polyester composition, and by melt-kneading the composition and the polyester, it is possible to easily increase the degree of polymerization of the polyester without performing solid-phase polymerization, thereby obtaining the polyester. The high-polymerized polyester can be used for various purposes such as fibers for clothing and industrial materials, polyester cotton, magnetic films, packaging materials, and various molded containers such as bottles. Furthermore, it is also possible to easily produce a polyester product having high heat resistance and mechanical properties by using, for example, a collected polyester waste having a reduced molecular weight.

Claims (4)

[Claims] 1. A polyester polymer having a main repeating unit as at least one kind of repeating unit selected from the group consisting of ethylene terephthalate, ethylene naphthalate, propylene terephthalate, propylene naphthalate, butylene terephthalate, and butylene naphthalate; A bisoxazoline compound-containing polyester composition comprising a bisoxazoline compound represented by the general formula (1) and simultaneously satisfying the following requirements (I) to (III): (I) The intrinsic viscosity is 0.40 to 1.00. (II) The amount of unreacted oxazoline functional groups in the polyester composition is 10 to 1400 eq / ton. (III) The melting point of the composition after the addition of the bisoxazoline compound is 4 ° C. or lower than the melting point of the polymer before the addition of the compound. Embedded image 2. The melting point of the composition after the addition of the bisoxazoline compound is 5 to less than the melting point of the polymer before the addition of the compound.
The composition of claim 1 which is 40 ° C lower. 3. The composition according to claim 1, wherein the bisoxazoline compound is a compound represented by the following structural formula (2). Embedded image 4. The bisoxazoline compound-containing polyester composition according to claim 1, having a terminal carboxyl group content of 5 to 80 eq / ton and an intrinsic viscosity of 0.30 to 0.9.
Melt kneading with a polyester polymer in the range of 0,
A method for producing a highly polymerized polyester, wherein the amount of unreacted oxazoline functional groups in the kneaded polyester composition is less than 10 eq / ton.