JP3407225B2 - Manufacturing method of flame resistant polyester - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing a polyester having excellent flame resistance and capable of forming fibers, films, boards and the like. 2. Description of the Related Art In recent years, from the standpoint of respect for human beings, the necessity of flame retardancy in various molded articles including fibers has been called out, and various efforts have been made. A method of adding a flame resistance-imparting substance during polymer production and copolymerizing or blending it in order to impart flame resistance even to a molded article produced from a linear polyester, and kneading the polyester with a flame resistance-imparting substance during the production of a molded article. In addition, a method of imparting flame resistance by post-processing a molded article made of polyester has been proposed. In view of the industrial value among these methods, a method of adding a flame resistance-imparting substance at the time of polymer production and copolymerizing is advantageous in that it is the simplest and does not impair various properties of the obtained molded article. For this purpose, various phosphorus compounds such as phosphoric esters such as triphenyl phosphate and phosphonic acids such as benzenephosphonic acid derivatives have been used for this purpose. [0003] However, when such a compound is used, the catalyst is deactivated during the production of the polyester, which leads to a significant increase in the polymerization time and the formation of a three-dimensional polymer. Was. Further, the phosphorus compound is scattered from the polyester production system, and the phosphorus compound to be introduced into the polyester is reduced, whereby the flame resistance effect of the polyester may be reduced, or the scattered phosphorus compound may cause problems such as environmental pollution. As a method for solving these problems, a method of copolymerizing carboxyphosphinic acid (Japanese Patent Publication No. 53-13479) is known. According to this method, the above problems can be solved, and a polymer having a high phosphorus content and a high degree of polymerization can be easily obtained.However, since phosphinic acid, which is a strong acid, is used, the number of ether bonds increases during polymerization, and Of the molded product, and the light resistance of the molded product is deteriorated. SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to form fibers, films and boards having excellent flame resistance and various physical properties. An object of the present invention is to provide a method for producing a flame-resistant polyester which can easily provide a product. Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems. As a result, when producing a polyester, a phosphorus compound is reacted with a basic organic compound, and then the polyester is produced. It has been found that by adding the compound to the system, ether bonds are suppressed and a flame-resistant polyester having excellent flame resistance can be obtained, and the present invention has finally been completed. That is, the present invention relates to the production of a polyester from one or more dicarboxylic acids or ester-forming derivatives thereof and one or more diols or ester-forming derivatives thereof and / or one or more oxycarboxylic acids or ester-forming derivatives thereof. , The phosphorus atom content in the polyester is 500 to 40,000 pp
A method for producing a flame-resistant polyester, comprising reacting a phosphonic acid or a derivative thereof represented by the following general formula 2 with a basic organic compound in advance so as to obtain m and adding the resulting compound. [0006] (Wherein, R ₁ represents a monovalent organic group having 1 to 18 carbon atoms, and R ₂ represents a monovalent organic group having 1 to 18 carbon atoms or a hydrogen atom). This will be described in detail. First, the phosphorus compound used in the production of the flame-resistant polyester of the present invention is a phosphonic acid represented by the general formula (2) or a derivative thereof. In the formula, preferred as R ₁ and R ₂ are methyl and ethyl. , N-propyl, isopropyl, n-butyl, tertiary butyl, n-hexyl, lower alkyl groups such as n-octyl, phenyl, 1-naphthyl,
Examples include an aryl group such as 2-naphthyl, an aralkyl group such as a benzyl group, and a cycloalkyl group such as a cyclopentyl and cyclohexyl group. Further, these hydrocarbon groups may be substituted by halogen atoms. Preferred examples of R ₂ include a carboxyl group, or an alkyl ester, an aryl ester, a cycloalkyl ester, a hydroxyl group, or a hydroxyalkoxycarbonyl group thereof. Preferred as A are alkylene groups such as methylene, ethylene, 1,2-propyne and 1,3-propylene, arylene groups such as 1,3-phenylene and 1,4-phenylene, 1,3-cyclohexylene, , 4
A cycloalkylene group such as cyclohexylene, 1,3-
Xylylene, 1,4-xylylene and the like can be mentioned. Examples of the compound represented by the general formula 2 include methylphosphonic acid, phenylphosphonic acid, monomethylmethylphosphonic acid, monoethylphenylphosphonic acid, and mono- (2-hydroxyethyl) phenylphosphonic acid. The phosphorus compound represented by the general formula 2 is synthesized by a conventionally known method. That is,
H. G. FIG. Hennig und G. Hilgetag, J.M. Prakt. C
hem. 29, 86 (1965); K.
Chajrullin et al., Z.obsc. Chim. 37 (196
7) Nr3, S. It is synthesized by the method described in 710-714 or the like. In the present invention, a phosphorus compound represented by the following general formula 3 may be used in combination with the phosphonic acid derivative represented by the general formula 2 above. Embedded image (Wherein, R ₁ is a monovalent organic group having 1 to 18 carbon atoms, R ₃ is a monovalent ester-forming functional group, and A is 1 carbon atom.)
-18 represents a divalent organic group. As specific examples of the phosphorus compound represented by the general formula 3, for example, (2-carboxyethyl) methylphosphinic acid, (2-carboxyethyl) phenylphosphinic acid, (2-methoxycarbonylethyl) methylphosphinic acid, ( (2-methoxycarbonylethyl) phenylphosphinic acid, (2-hydroxyethoxycarbonylethyl) methylphosphinic acid, (2
-Hydroxyethoxycarbonylethyl) phenylphosphinic acid, (4-carboxyphenyl) phenylphosphinic acid, (2-hydroxyethyl) phenylphosphinic acid and the like. Next, in the present invention, examples of the basic organic compound to be reacted with the phosphonic acid represented by the general formula 2 or its derivative include triethylamine, tri-n-butylamine, cyclohexylamine, pyridine, aniline, dimethylaniline and the like. And organic acetates such as triethylamine acetate and cyclohexylamine acetate, and carboxylic acid amides such as dimethylformamide and dimethylacetamide. Triethylamine is particularly preferred from the viewpoint of polymer color tone. The reaction with the phosphorus compound may be either solventless or in a solvent, preferably,
It is advantageous in the addition step to carry out the reaction in a diol or an ester-forming derivative thereof, which is a polyester production raw material. When the basic compound is a metal salt such as sodium hydroxide or sodium acetate, during the production of polyester,
Since the metal salt of an acid component such as terephthalic acid precipitates and the polymer becomes cloudy, it cannot be used. In the present invention, the phosphonic acid represented by the general formula 2 or a derivative thereof (hereinafter also referred to as a phosphorus compound) is contained in a polymer in an amount of 500 to 40,000 ppm as a phosphorus atom.
It is appropriate to use it in such a manner that it is contained. In particular, it is preferable to use 2,000 to 10,000 ppm for ordinary polyester for fibers. If the amount of the phosphorus compound used is smaller than the above range, it becomes difficult to obtain a polyester having a desired flame resistance, while if the amount used is larger than the above range, the physical properties of the obtained polyester deteriorate. In addition, it is not preferable because the operability at the time of producing the polyester is reduced. In the present invention, the method of adding the above phosphorus compound to the production system when producing the flame resistant polyester is not particularly limited. For example, when a polyester is produced by a so-called transesterification method between a dicarboxylic acid diester and a diol, it is preferable to add the phosphorus compound at the time of transesterification. Also, when producing a polyester by a so-called esterification method of a dicarboxylic acid and a diol, it is desirable that the above-mentioned phosphorus compound is present during the esterification reaction. The phosphorus compound may be added after the transesterification reaction and the esterification reaction, that is, during the polycondensation. However, the addition at a later stage of the polycondensation is not preferable because the polycondensation time is greatly extended. In the present invention, the dicarboxylic acid component used for producing the flame-resistant polyester includes terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 4,4-diphenyl Dicarboxylic acid, bis (4-carboxyphenyl) ether, bis (4-carboxyphenyl) sulfone, 1,2-bis (carboxyphenoxy) ethane, 5
-Aromatic carboxylic acids such as sodium sulfoisophthalic acid, 2,5-dibromoterephthalic acid and tetrabromoterephthalic acid, aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid and hexahydroterephthalic acid, or a mixture thereof Is mentioned. On the other hand, as the diol component, ethylene glycol, 1,2-propylene glycol, trimethylene glycol, tetramethylene glycol, neopentyl glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, diethylene glycol, polyethylene glycol, or these And mixtures thereof. Examples of the oxycarboxylic acid component include p-oxybenzoic acid and p-hydroxyethoxybenzoic acid. In the present invention, the flame-resistant polyester is produced from the above-mentioned dicarboxylic acid component, diol component and / or oxycarboxylic acid component, and a phosphorus compound represented by the general formula 2 reacted with a basic organic compound. The transesterification or esterification reaction can be carried out by a conventionally known method. That is, as a catalyst for the transesterification and esterification reaction, conventionally known metal compounds such as alkaline earth metals, zinc, manganese, cobalt, and titanium can be used. The same applies for polycondensation. That is, in the present invention, conventionally known antimony compounds, germanium compounds, cobalt compounds and titanium compounds can be used as polycondensation catalysts. In the production of flame-resistant polyester according to the present invention, the use of commonly used additives, for example, pigments such as titanium oxide and carbon black, further stabilizers, plasticizers, electrostatic agents and the like is out of the spirit of the present invention. is not. As described above in detail, according to the present invention, the increase in ether bonds which cannot be avoided when phosphinic acid or phosphonic acid, which is a strong acid, is used is greatly reduced by the ordinary polyester production method. It is possible to obtain high-quality flame-resistant polyester very easily by suppressing it without changing it, because phosphinic acid or phosphonic acid, which is a strong acid, is neutralized with a basic organic compound in advance, and the reaction is carried out. It is believed that the acidity in the system was reduced, resulting in suppression of the ether linkage. The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.
In the examples, “parts” means “parts by weight” and “percent” means “weight percent”, and the intrinsic viscosity is phenol-1,1,2,2, -tetrachloroethane (weight ratio 3: 2).
It is determined from the value measured at 30 ° C. in a mixed solvent.
The content of diethylene glycol (DEG) was expressed as mol% of DEG in all glycol units in the polymer. The flame resistance is obtained by spinning and drawing a polyester polymer by a conventional method to form a knitted yarn, and 1 gram of the yarn is 10 cm in length.
Rounded and inserted into a 10 mm diameter wire coil, 45
When the fire is extinguished by keeping the angle of ゜ and igniting from the lower end and moving away from the fire source, the ignition is repeated again, and the number of ignitions required to completely burn all the samples is calculated and expressed as an average value of 5 samples. It was done. Example 1 In a four-necked flask equipped with a stirrer, thermometer and dropping funnel, 46 parts of phenylphosphonic acid and 100 parts of ethylene glycol were charged and dissolved by heating to 50 to 60 ° C.
Further, 59 parts of triethylamine was dropped from the dropping funnel while keeping the temperature at 50 ° C. or lower, and reacted. 1236 parts of terephthalic acid, 955 parts of ethylene glycol, and an ethylene glycol solution of a phosphorus compound obtained by the above reaction were charged into a stainless steel autoclave equipped with a stirrer, a distillation column, and a pressure regulator, and 0.55 part of antimony trioxide was further added. , Triethylamine, 11 parts and 230
The esterification reaction was performed for 2 hours at a temperature of 2.5 ° C. and a gauge pressure of 2.5 kg / cm ² while sequentially removing water generated by the esterification from the system. Subsequently, the temperature of the system was raised to 275 ° C. in one hour, and during this time, the pressure of the system was gradually reduced to 0.1 mmHg.
The polycondensation was performed under these conditions for 2 hours. [Η] of the obtained polymer was 0.61 and the phosphorus content was 5880 pp.
m, DEG content was 2.6%. A yarn obtained by spinning and drawing this polymer by a conventional method has a flame resistance of 5.6.
It was times. Example 2 A polyester was produced in the same manner as in Example 1, except that 27 parts of methylphosphonic acid was used instead of 46 parts of phenylphosphonic acid. [Η] of the obtained polymer was 0.63, phosphorus content was 5830 ppm, DE
G was 2.7%, and the number of times of flame resistance was 5.0 times. Example 3 In Example 1, instead of 59 parts of triethylamine,
A polyester was produced in the same manner as in Example 1 except that 94 parts of triethylamine acetate was used. [Η] of the obtained polymer was 0.63, phosphorus content was 5890 ppm, DE
G was 2.8%, and the flame resistance was 4.9 times. Comparative Example 1 The procedure of Example 1 was repeated except that 46 parts of phenylphosphonic acid were used as dissolved in 100 parts of ethylene glycol.
A polyester was produced in the same manner as described above. [Η] of the obtained polymer was 0.62, and the phosphorus content was 5,230 ppm. DEG was as high as 5.2%, and the number of times of flame resistance was 4.6. Comparative Example 2 In Example 1, 46 parts of phenylphosphonic acid was dissolved in 100 parts of ethylene glycol to prepare an ethylene glycol solution of a phosphorus compound. 1236 parts of terephthalic acid, 955 parts of ethylene glycol, and an ethylene glycol solution of a phosphorus compound obtained by the above reaction were charged into a stainless steel autoclave equipped with a stirrer, a distillation column, and a pressure regulator, and 0.55 part of antimony trioxide was further added. And 59 parts of triethylamine, and a polyester was produced in the same manner as in Example 1 below. [Η] of the obtained polymer is 0.6
3. The phosphorus content was 5980 ppm, DEG was as high as 5.1%, and the number of times of flame resistance was 4.9. Example 4 A four-necked flask equipped with a stirrer, a thermometer, and a dropping funnel was charged with 33 parts of (2-methoxycarbonylethyl) phenylphosphinic acid, 23 parts of phenylphosphonic acid, and 100 parts of ethylene glycol. Heated to 50-60 ° C to dissolve. Further, 30 parts of triethylamine was dropped and reacted from the dropping funnel while keeping the temperature at 50 ° C. or lower. 1236 parts of terephthalic acid, 955 parts of ethylene glycol, and an ethylene glycol solution of a phosphorus compound obtained by the above reaction were charged into a stainless steel autoclave equipped with a stirrer, a distillation column, and a pressure regulator, and 0.55 part of antimony trioxide was further added. , Triethylamine and 11 parts
The esterification reaction was performed for 2 hours at 30 ° C. and a gauge pressure of 2.5 kg / cm ² while sequentially removing the water produced by the esterification from the system. Subsequently, the temperature of the system was raised to 275 ° C. in one hour, and during this time the pressure of the system was gradually reduced to 0.1 mm.
Hg, and polycondensation was performed under these conditions for 2 hours. [Η] of the obtained polymer was 0.63 and the phosphorus content was 5920.
ppm, DEG content was 2.3%. This polymer was spun and drawn by a conventional method, and the yarn obtained had a flame resistance of 4.9 times. Example 5 A four-necked flask equipped with a stirrer, a thermometer and a dropping funnel was charged with 46 parts of phenylphosphonic acid and 100 parts of ethylene glycol, and dissolved by heating to 50 to 60 ° C.
Further, 30 parts of triethylamine was dropped and reacted from the dropping funnel while keeping the temperature at 50 ° C. or lower. 1444 parts of dimethyl terephthalate, 955 parts of ethylene glycol, and 0.34 part of zinc acetate were charged into a stainless steel autoclave equipped with a stirrer, a distillation column, and a pressure regulator.
The transesterification was performed at 50 to 230 ° C for 2 hours. Subsequently, 0.55 parts of an ethylene glycol solution of the phosphorus compound obtained by the above reaction and antimony trioxide were added, and a polyester was produced in the same manner as in Example 1 below. [Η] of the obtained polymer was 0.64 and the phosphorus content was 5920 ppm,
DEG content was 1.4%. The polymer was spun and drawn by a conventional method, and the yarn obtained had a flame resistance of 5.1 times. Comparative Example 3 A four-necked flask equipped with a stirrer, a thermometer and a dropping funnel was charged with 2 parts of methylphosphonic acid and 100 parts of ethylene glycol, and dissolved by heating to 50 to 60 ° C. Further, 2.2 parts of triethylamine was added dropwise from a dropping funnel while keeping the temperature at 50 ° C. or lower to cause a reaction. mixer,
1236 parts of terephthalic acid and ethylene glycol 9 were placed in a stainless steel autoclave equipped with a distillation column and a pressure regulator.
15 parts, and an ethylene glycol solution of the phosphorus compound obtained by the above reaction were charged, and antimony trioxide was further added to 0.5 part.
Five parts and 11 parts of triethylamine were added, and an esterification reaction was performed for 2 hours at 230 ° C. and a gauge pressure of 2.5 kg / cm ² while sequentially removing water generated by the esterification from the system. Subsequently, the temperature of the system was raised to 275 ° C. in 1 hour, and during this time, the pressure of the system was gradually reduced to 0.1 mmHg, and polycondensation was performed under these conditions for 2 hours. The obtained polymer had an [η] of 0.64, a phosphorus content of 220 ppm, and DEG.
Content was 1.2%. This polymer was spun and drawn by a conventional method, and the number of flame resistances of the yarn obtained was 1.1 times. According to the method of the present invention, that is, a method of reacting a strong acid, phosphonic acid, with a basic organic compound and then adding it to a polyester production system,
Since the ether bond can be suppressed and the polyester excellent in flame resistance can be easily obtained without greatly changing the usual polyester production method, it greatly contributes to the industry.

Claims (1)

(57) [Claims 1] One or more dicarboxylic acids or ester-forming derivatives thereof and one or more diols or ester-forming derivatives thereof and / or one or more oxycarboxylic acids or ester formation thereof When a polyester is produced from an acidic derivative, a phosphonic acid or a derivative thereof represented by the following general formula 1 is added in advance by reacting with a basic organic compound so that the phosphorus atom content in the polyester is 500 to 40000 ppm. A method for producing a flame resistant polyester. Embedded image (Wherein, R ₁ represents a monovalent organic group having 1 to 18 carbon atoms, and R ₂ represents a monovalent organic group having 1 to 18 carbon atoms or a hydrogen atom.)