JP2006063181A - Polyester produced by using novel polyester polymerization catalyst - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester which can be applied to fibers for clothing, fibers for industrial materials, various films, sheets, bottles, various types of molded products of engineering plastics, and coating materials, adhesives and the like by producing the polyester with the use of a novel polymerization catalyst other than an antimony compound. <P>SOLUTION: The polyester is produced by using a polyester polymerization catalyst having, as a main component, a solid solution composed of an aluminum compound and a magnesium compound and contains 0.1-1.0 mass% hindered phenol antioxidant. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polyester produced using a novel polyester polymerization catalyst that does not use an antimony compound.

  Polyester, especially polyethylene terephthalate (hereinafter abbreviated as PET), has excellent mechanical and chemical properties, and is used for many purposes, such as textiles for clothing and industrial materials, packaging, and magnetic tape. It is applied to molded products such as various films and sheets, bottles and engineering plastics.

  The industrial production method of PET includes a step of obtaining bis (2-hydroxyethyl) terephthalate by esterification or transesterification of terephthalic acid or dimethyl terephthalate and ethylene glycol, and using a catalyst at high temperature under vacuum. It consists of a process of polycondensation. At this time, antimony trioxide is widely used as a polycondensation catalyst because it is inexpensive and has excellent catalytic activity. However, when antimony trioxide is used, metal antimony is precipitated at the time of polycondensation, so that there is a problem that darkening and foreign matter are generated in PET. To solve these problems, a method using a compound of antimony trioxide, bismuth and selenium as a polycondensation catalyst (Patent Document 1), a method using antimony trioxide containing an oxide of sodium and iron (Patent Document 2) Etc. have been proposed.

  However, recently, since the influence of antimony on the environment has been pointed out, a polycondensation catalyst as an alternative to antimony trioxide has been studied. Tetraalkoxy titanate and germanium have been widely known. However, PET produced using the former has a problem that it is markedly colored and easily causes thermal decomposition, and the latter is very expensive. There is a problem that there is a problem, and since the catalyst concentration in the reaction system changes due to the fact that it tends to be distilled out of the reaction system during the polymerization, it is difficult to control the polymerization.

Furthermore, Patent Document 3 proposes that by sequentially adding an aluminum compound and a magnesium compound, the catalyst activity is higher than the sum of their catalytic activities. There were problems that coarse foreign matters such as decomposition products were generated and the color tone was not sufficiently excellent.
Japanese Patent No. 2666502 JP 9-291141 A JP 2000-302854 A

  This invention solves said subject and provides the polyester manufactured using the novel polycondensation catalyst other than an antimony compound.

The present invention solves the above-mentioned problems, and the gist thereof is as follows.
A polyester produced by using a polyester polymerization catalyst whose main component is a solid solution composed of an aluminum compound and a magnesium compound, characterized in that it contains 0.1 to 1.0% by mass of a hindered phenol-based antioxidant. Polyester to do.

  According to the polyester polymerization catalyst having a solid solution composed of an aluminum compound and a magnesium compound as a main component, an appropriate polymerization activity is obtained by the combined effect of the magnesium compound and the aluminum compound, and a polyester having excellent transparency is provided. Furthermore, by adding a hindered phenol antioxidant to the polyester produced using this polymerization catalyst, a polyester having good color tone, transparency and stability over time is provided. The polyester of the present invention can be applied to fibers for clothing, fibers for industrial materials, various films, sheets, various molded products such as bottles and engineering plastics, paints, adhesives, and the like.

  Hereinafter, the present invention will be described in detail.

  The polyester polymerization catalyst used for the production of the polyester of the present invention mainly comprises a solid solution comprising an aluminum compound and a magnesium compound. By using an aluminum compound and a magnesium compound as a solid solution, an appropriate polymerization activity is obtained, and the refractive index of the solid solution is about 1.5, which is close to the refractive index 1.6 of PET, which is a typical polyester. Since it is a value, transparency is also good. If the aluminum compound and the magnesium compound are added simultaneously or sequentially as separate compounds rather than as a solid solution, foreign matters such as catalyst decomposition products are generated in the polymer, and the color tone becomes insufficient.

  A solid solution composed of an aluminum compound and a magnesium compound is a solid in which the respective phases are melted to form a uniform phase, and a part of these crystal lattices can be replaced by other atoms to change the composition. The molar ratio in the solid solution is aluminum / magnesium = 0.1 to 10, and is preferably 0.2 to 5 in order to obtain a polyester having excellent transparency.

  Examples of aluminum compounds that form solid solutions include aluminum hydroxide, aluminum hydroxide chloride, aluminum formate, aluminum acetate, aluminum propionate, aluminum oxalate, aluminum acrylate, aluminum stearate, and aluminum benzoate, Inorganic acid salts such as aluminum chloride, aluminum carbonate, aluminum phosphate, aluminum methoxide, aluminum ethoxide, aluminum n-propoxide, aluminum n-butoxide and other aluminum alkoxides, aluminum acetylacetonate, aluminum acetylacetate, aluminum ethylacetate Aluminum chelate compounds such as acetate, organic materials such as trimethylaluminum and triethylaluminum Aluminum compounds and these partial hydrolyzate, aluminum oxide, and metal aluminum. Of these, carboxylates and inorganic acid salts are preferable, and among these, aluminum hydroxide, aluminum acetate, and aluminum chloride are particularly preferable.

  Moreover, as a magnesium compound which forms a solid solution, magnesium hydroxide, magnesium carbonate, magnesium acetate, magnesium acetylacetonate, carboxylates other than acetic acid, etc. are mentioned, and especially magnesium hydroxide and magnesium carbonate are preferable.

  One or both of the aluminum compound and the magnesium compound may be a solid solution of two or more compounds.

  Further, the polyester polymerization catalyst may contain a metal other than magnesium and aluminum, or a compound thereof, in the solid solution. Examples of other metals include zinc, titanium, tin, cobalt, manganese, niobium, tantalum, tungsten, indium, zirconium, hafnium, silicon, iron, nickel, and gallium.

  In this invention, it is preferable that the usage-amount of a polyester polymerization catalyst shall be 80-500 ppm with respect to polyester, More preferably, it is 100-400 ppm. In the present invention, all ppm are ppm by mass.

  The polyester of the present invention produced using the polyester polymerization catalyst is selected from one or more selected from polycarboxylic acids containing dicarboxylic acids and ester-forming derivatives thereof and polyhydric alcohols containing glycols. Examples thereof include those obtained from one or more types, those obtained from hydroxycarboxylic acids and their ester-forming derivatives, those composed of cyclic esters, and copolymers or mixtures thereof.

  Dicarboxylic acids include succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, dodecanedicarboxylic acid, tetradecanedicarboxylic acid, hexadecanedicarboxylic acid, eicosanedioic acid , Tricyclodecane dicarboxylic acid, 1,3-cyclobutane dicarboxylic acid, 1,3-cyclopentane dicarboxylic acid, 1,2-cyclohexane dicarboxylic acid, 1,3-cyclohexane dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid, 2, Saturated aliphatic dicarboxylic acids exemplified by 5-norbornane dicarboxylic acid, dimer acid and the like, or ester-forming derivatives thereof, unsaturated aliphatic dicarboxylic acids exemplified by fumaric acid, maleic acid, itaconic acid and the like, and ester formation thereof Sex derivatives, Lusophthalic acid, isophthalic acid, terephthalic acid, 5- (alkali metal) sulfoisophthalic acid, diphenic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6- Naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 4,4′-biphenylsulfonedicarboxylic acid, 4,4′-biphenyletherdicarboxylic acid, 1,2-bis (phenoxy) ethane Examples include aromatic dicarboxylic acids exemplified by -p, p'-dicarboxylic acid, pamoic acid, anthracene dicarboxylic acid, and the like, and ester-forming derivatives thereof. Among these dicarboxylic acids, terephthalic acid and isophthalic acid are preferable.

  As polyvalent carboxylic acids other than these dicarboxylic acids, ethanetricarboxylic acid, propanetricarboxylic acid, butanetetracarboxylic acid, pyromellitic acid, trimellitic acid, trimesic acid, 3,4,3 ′, 4′-biphenyltetracarboxylic acid, And ester-forming derivatives thereof.

  Examples of the hydroxycarboxylic acid include lactic acid, citric acid, malic acid, tartaric acid, hydroxyacetic acid, 3-hydroxybutyric acid, p-hydroxybenzoic acid, p- (2-hydroxyethoxy) benzoic acid, 4-hydroxycyclohexanecarboxylic acid, or these And ester-forming derivatives thereof.

  Examples of ester-forming derivatives of polyvalent carboxylic acids or hydroxycarboxylic acids include these alkyl esters, acid chlorides, acid anhydrides, and the like.

  As glycol, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol 1,4-butylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,2 -Cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, 1,4-cyclohexanediethanol, 1,10-decamethylene glycol, 1,12-dodecanediol, polyester Aliphatic glycols exemplified by lene glycol, polytrimethylene glycol, polytetramethylene glycol, hydroquinone, 4,4′-dihydroxybisphenol, 1,4-bis (β-hydroxyethoxy) benzene, 1,4-bis ( β-hydroxyethoxyphenyl) sulfone, bis (p-hydroxyphenyl) ether, bis (p-hydroxyphenyl) sulfone, bis (p-hydroxyphenyl) methane, 1,2-bis (p-hydroxyphenyl) ethane, bisphenol A , Bisphenol C, 2,5-naphthalenediol, aromatic glycols exemplified by glycols obtained by adding ethylene oxide to these glycols, etc. Among these glycols, ethylene glycol and 1,4-butylene glycol Preferred.

  Examples of polyhydric alcohols other than these glycols include trimethylolmethane, trimethylolethane, trimethylolpropane, pentaerythritol, glycerol, hexanetriol and the like.

  Examples of the cyclic ester include ε-caprolactone, β-propiolactone, β-methyl-β-propiolactone, δ-valerolactone, glycolide, and lactide.

  Preferable specific examples of the polyester of the present invention include polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, poly (1,4-cyclohexanedimethylene terephthalate), polyethylene naphthalate, polybutylene naphthalate, and copolymers thereof. Among them, polyethylene terephthalate is particularly preferable.

  The polyester of the present invention can be produced by a conventionally known method. For example, either a method of polycondensation after esterification of terephthalic acid and ethylene glycol, or a method of polycondensation after transesterification of an alkyl ester of terephthalic acid such as dimethyl terephthalate with ethylene glycol It can also be done by the method.

  In the present invention, the polyester polymerization catalyst is preferably added before the start of the polycondensation reaction, but may be added to the reaction system at any stage before the start of the esterification reaction or transesterification reaction and during the reaction.

  In the present invention, the polyester polymerization catalyst may be added in a powder state or in a slurry of a solvent such as ethylene glycol.

  The polyester of the present invention needs to contain 0.1 to 1.0% by mass of a hindered phenolic antioxidant.

  As the hindered phenol antioxidant, 2,6-di-t-butyl-4-methylphenol, n-octadecyl-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) Propionate, tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, 4, 4′-butylidenebis- (3-methyl-6-tert-butylphenol), triethylene glycol-bis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate], 3,9-bis { 2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1′-dimethylethyl} -2,4 , 10-tetraoxaspiro [5,5] undecane, etc. are used, but tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane in terms of effect and cost Is preferred.

  The polyester of the present invention produced using the polymerization catalyst improves the temporal stability by containing a hindered phenol antioxidant, but if the content is less than 0.1% by mass, sufficient effects are obtained. If a long time elapses, the intrinsic viscosity may decrease or the color tone may deteriorate after molding. Moreover, when content exceeds 1.0 mass%, since the color tone and transparency of polyester deteriorate, it is unpreferable.

  The hindered phenol-based antioxidant is preferably added before the start of the polycondensation reaction, but can be added to the reaction system before the esterification reaction or the transesterification reaction and at any stage during the reaction.

  The method for adding the hindered phenol-based antioxidant may be in a powder state or in the form of a slurry of a solvent such as ethylene glycol.

  The polyester of the present invention contains other optional polymers and stabilizers, antistatic agents, antifoaming agents, dyeability improving agents, dyes, pigments, matting agents, fluorescent whitening agents, and other additives. May be.

Next, the present invention will be described specifically by way of examples. In the examples, the characteristic evaluation was performed as follows.
(A) Content of hindered phenolic antioxidant Polyester is dissolved in a mixed solution having a volume ratio of deuterated hexafluoroisopropanol and deuterated chloroform of 1/20, and a JEOL LA-400 type NMR apparatus. ¹ H-NMR was measured at ¹ and the content was determined from the integrated intensity of the proton peak of each component of the obtained chart.
(B) Intrinsic viscosity Measured at a temperature of 20 ° C. using an equal weight mixture of phenol and ethane tetrachloride as a solvent.
(C) Color tone of polyester (b value)
Measurement was performed using a color difference meter ND-Σ80 manufactured by Nippon Denshoku Industries Co., Ltd. The color tone was determined using a Hunter Lab colorimeter. L value is lightness (larger value is brighter), a value is red-green hue (+ is reddish,-is greenish), b value is yellow-blue hue (+ is yellowish,-is Blue).
Here, if b value was 7 or less, it was set as the pass.
(D) Transparency of polyester The polyester pellets were dried by a conventional method, put into a transparent glass tube having an inner diameter of 6 cm and an outer diameter of 6.6 cm, and kept at 280 ° C. for 30 minutes in a nitrogen atmosphere to melt. Transparency was determined by comparing the apparent turbidity with a standard sample. The standard sample is a similar glass tube in which titanium dioxide is dispersed in molten acrylic resin at different concentrations.
S1: Titanium dioxide concentration 0
S2: Titanium dioxide concentration 0.5ppm
S3: Titanium dioxide concentration 1.0 ppm
In addition, the transparency was determined according to the following three levels.
○: Turbidity is between standard samples S1 and S2, and transparency is good Δ: Turbidity is between standard samples S2 and S3, transparency is normal x: Turbidity exceeds standard sample S3 (E) Heat treatment As a aging acceleration test, the polyester was allowed to stand for 120 hours in a normal pressure air atmosphere at 130 ° C. Intrinsic viscosity [η] ₁ before treatment and intrinsic viscosity [η] ₂ after treatment, b value (b ₁ ) of polyester chip before treatment, and b value (b ₂ ) of polyester chip after treatment The ratio [η] ₂ / [η] ₁ of the intrinsic viscosity before and after the treatment is 0.90 or more, and the difference in b value (b ₂ −b ₁ ) between the chips before and after the treatment is 3.0 or less. did.

In addition, the solid solution used as a polymerization catalyst in an Example is as follows.
-HT-P made by Sakai Chemical
A solid solution consisting of aluminum hydroxide, magnesium hydroxide and magnesium carbonate and having an Al / Mg ratio of 0.4.
・ HT-7 manufactured by Sakai Chemical
In the solid solution of HT-P, zinc oxide is contained so that the molar ratio of Zn / (Al + Mg) is 0.05.

Example 1
A slurry having a molar ratio of terephthalic acid and ethylene glycol of 1 / 1.6 is continuously fed to an esterification reaction vessel in which bis (β-hydroxyethyl) terephthalate and its low polymer are present, at a temperature of 250 ° C. and a pressure of The reaction was carried out under the condition of 50 hPaG, and the residence time was set to 8 hours to continuously obtain a PET oligomer (average polymerization degree: 7) having an esterification reaction rate of 95%.
60.3 kg of this PET oligomer was transferred to a polymerization reactor. As a polymerization catalyst, 14.4 g of HT-P (amount to be 250 ppm with respect to polyester) followed by tetrakis [methylene- 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane (Irganox-1010 manufactured by Ciba Specialty) was added, and the pressure in the polycondensation reactor was reduced to a final value of 0. A polyester having an intrinsic viscosity ([η] ₁ ) of 0.65 and a b value (b ₁ ) of 3.6 was obtained by performing a polycondensation reaction at 2.9 hPa and 280 ° C. for 3 hours. Further, after this polyester was heat-treated at 130 ° C. in an air atmosphere for 120 hours, the intrinsic viscosity ([η] ₂ ) was 0.63, and the b value (b ₂ ) of the plate was 5.1. The ratio of intrinsic viscosity before and after [η] ₂ / [η] ₁ was 0.97, and the difference b ₂ -b ₁ between the b values of the plate before and after heat treatment was 1.5. Table 1 shows the characteristic values of the obtained polymer.

Example 2
A polyester was polymerized in the same manner as in Example 1 except that the amount of the hindered phenol antioxidant was changed as shown in Table 1. Table 1 shows the characteristic values of the obtained polymer.

Example 3
A polyester was polymerized in the same manner as in Example 1 except that 14.4 g of HT-7 (an amount of 250 ppm with respect to the polyester) was used instead of HT-P as a polymerization catalyst. Table 1 shows the characteristic values of the obtained polymer.

Comparative Examples 1-3
A polyester was polymerized in the same manner as in Example 1 except that the amount of the hindered phenol antioxidant was changed as shown in Table 1. Table 1 shows the characteristic values of the obtained polymer.

Comparative Example 4
In place of HT-P, except that 8.6 g of aluminum acetate (amount of 150 ppm with respect to polyester) and 6.0 g of magnesium acetate (amount of 105 ppm with respect to polyester) were sequentially added, The polyester was polymerized in the same manner as in Example 1. Table 1 shows the characteristic values of the obtained polymer.

Comparative Example 5
Instead of HT-P, polyester was polymerized in the same manner as in Example 1 except that 14.4 g of antimony trioxide was added as a polymerization catalyst (an amount of 250 ppm based on the polyester). Table 1 shows the characteristic values of the obtained polymer.

  In Examples 1 to 3, polymers having good characteristics and stability over time were obtained, but Comparative Examples 1 to 4 had the following problems.

In Comparative Example 1, since no antioxidant was added, the stability of the polymer with time was not good, and the decrease in intrinsic viscosity and b value of the polyester after heat treatment were large.
In Comparative Example 2, since the addition amount of the antioxidant was small, a sufficient effect could not be obtained to improve the temporal stability of the polymer, and the decrease in the intrinsic viscosity and the b value of the polyester after the heat treatment were large.
In Comparative Example 3, since the amount of the antioxidant added was large, the transparency of the polymer was poor and the b value was also high.
In Comparative Example 4, when aluminum acetate and magnesium acetate were sequentially added, the obtained polymer had poor transparency and a high b value. Moreover, the stability over time was poor, and the b value of the polyester after heat treatment was greatly deteriorated and the intrinsic viscosity was greatly reduced.
In Comparative Example 5, when antimony trioxide was used as a polymerization catalyst, the obtained polymer had poor transparency.

Claims (1)

A polyester produced by using a polyester polymerization catalyst whose main component is a solid solution composed of an aluminum compound and a magnesium compound, characterized in that it contains 0.1 to 1.0% by mass of a hindered phenol-based antioxidant. Polyester to do.