JP4086983B2 - Polyester manufacturing method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
  The present invention relates to a method for producing a polyester that is suitably used for applications such as bottles, films, and sheet molding. More specifically, the present invention relates to polycondensation of aromatic dicarboxylic acids and aliphatic diols at a high polymerization rate. It is related with the manufacturing method of polyester which can do.
[0002]
TECHNICAL BACKGROUND OF THE INVENTION
  Polyester, particularly polyethylene terephthalate (PET), is excellent in mechanical strength, heat resistance, transparency and gas barrier properties, and is suitably used as a material for beverage filling containers such as juices, soft drinks and carbonated drinks.
[0003]
  Such a polyester is usually produced from dicarboxylic acids such as terephthalic acid and aliphatic diols such as ethylene glycol as raw materials. Specifically, first, a low-order condensate (ester low polymer) is formed by an esterification reaction of an aromatic dicarboxylic acid and an aliphatic diol, and then this low-order condensate is formed in the presence of a polycondensation catalyst. It is produced by deglycolization reaction (liquid phase polycondensation) to increase the molecular weight, and further solid phase polycondensation.
[0004]
  The polyester thus produced is generally supplied to a molding machine such as an injection molding machine to form a hollow molded body preform, and then the preform is inserted into a mold having a predetermined shape and stretch blow molded to form a hollow molded container. Has been.
[0005]
  By the way, in the manufacturing method of the above polyesters, an antimony compound, a germanium compound, etc. are conventionally used as a polycondensation catalyst. However, polyethylene terephthalate produced using an antimony compound as a catalyst is inferior to polyethylene terephthalate produced using a germanium compound as a catalyst in terms of transparency and heat resistance.
[0006]
  Moreover, since the germanium compound is quite expensive, there is a problem that the production cost of the polyester is increased. For this reason, in order to reduce manufacturing costs, processes such as collecting and reusing germanium compounds scattered during polymerization have been studied.
[0007]
  The present inventor has intensively studied a polycondensation catalyst at the time of producing a polyester in view of the above-described conventional technology.Aluminum compoundBy using together, it was found that the amount of expensive germanium compound used can be reduced, and that the polyester can be produced with higher catalytic activity than when the germanium compound is used alone, and the present invention has been completed.
[0008]
OBJECT OF THE INVENTION
  An object of the present invention is to provide a method for producing a polyester capable of polycondensing aromatic dicarboxylic acids and aliphatic diols with high catalytic activity even if the amount of germanium compound used is reduced.
[0009]
SUMMARY OF THE INVENTION
  The method for producing a polyester according to the present invention comprises the steps of polycondensing an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol or an ester-forming derivative thereof in the presence of a polycondensation catalyst. , (I) a germanium compound as a polycondensation catalyst,(ii) Catalyst comprising aluminum compoundIt is characterized by using.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
  Hereafter, the manufacturing method of polyester of this invention is demonstrated concretely. First, the polycondensation catalyst used in the method for producing a polyester according to the present invention will be described.
[0011]
  In the present invention, as the polycondensation catalyst (i) a germanium compound,(ii) Aluminum compoundA catalyst consisting of
[0012]
  Specific examples of the germanium compound include germanium dioxide, germanium tetraethoxide, germanium tetra n-butoxide, and the like. Of these, germanium dioxide is particularly preferably used.
[0013]
  Examples of the aluminum compound include an aluminum salt of a fatty acid such as aluminum acetate, aluminum carbonate, or an acetylacetonate salt of aluminum, and aluminum acetate or aluminum carbonate is particularly preferable.
[0021]
  Like the above(ii) Aluminum compoundMay use 2 or more types.
[0022]
  (I) a germanium compound in the polycondensation catalyst used in the present invention;(ii) Aluminum compoundThe molar ratio (i) / (ii) is 2/1 to 2/8, preferably 1/1 to 1/2, in terms of metal atoms.
[0023]
  Such a polycondensation catalyst is, in terms of metal atoms in the polycondensation catalyst, 0.001 to 0.2 mol%, preferably 0.002 to 0.1 mol% of the germanium compound, based on the aromatic dicarboxylic acid.(ii) Aluminum compoundIs preferably 0.005 to 0.3 mol%, preferably 0.010 to 0.2 mol%.
[Production method of polyester]
  In the manufacturing method of polyester which concerns on this invention, it is not specifically limited except using an above-mentioned polycondensation catalyst including an esterification process and a polycondensation process.
[0024]
  In such a process, the polycondensation catalyst only needs to be present during the polycondensation reaction, and can be added to either the polycondensation step, the esterification step, or the raw slurry preparation step. It may be added simultaneously in any step, or may be added separately in separate steps. (I) a germanium compound and (ii)With aluminum compoundsA catalyst prepared by mixing (reacting) may be used.
[Raw materials]
  The method for producing a polyester according to the present invention uses an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol or an ester-forming derivative thereof as raw materials.
[0025]
  Examples of the aromatic dicarboxylic acid used in the present invention include terephthalic acid, phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid and the like.
[0026]
  Examples of the aliphatic diol include ethylene glycol, trimethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, hexanemethylene glycol, and dodecamethylene glycol.
[0027]
  Moreover, in this invention, aliphatic dicarboxylic acids, such as adipic acid, sebacic acid, azelaic acid, and decanedicarboxylic acid, alicyclic dicarboxylic acids, such as cyclohexane dicarboxylic acid, etc. can also be used as a raw material with aromatic dicarboxylic acid.
[0028]
  Furthermore, alicyclic glycols such as cyclohexanedimethanol, bisphenol, hydroquinone, aromatic diols of 2,2-bis (4-β-hydroxyethoxyphenyl) propanes, etc. can be used as raw materials together with aliphatic diols. it can. In the production method of the present invention, either a batch method or a continuous method may be employed. Hereinafter, although an example of a continuous system is demonstrated, this invention is not limited to these.
[Esterification process]
  First, when producing polyester, an aromatic dicarboxylic acid or an ester-forming derivative thereof is esterified with an aliphatic diol or an ester-forming derivative thereof.
[0029]
  Specifically, a slurry containing an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol or an ester-forming derivative thereof is prepared. Such a slurry contains 1.005 to 1.4 mol, preferably 1.01 to 1.3 mol of an aliphatic diol or an ester-forming derivative thereof, per 1 mol of an aromatic dicarboxylic acid or an ester-forming derivative thereof. This slurry is continuously supplied to the esterification reaction step.
[0030]
  The esterification reaction is preferably carried out using an apparatus in which two or more reactors are connected in series under conditions where the aliphatic diol is refluxed while removing water generated by the reaction from the system using a rectification column. .
[0031]
  The esterification reaction step is usually performed in multiple stages, and the first stage esterification reaction is usually a reaction temperature of 240 to 270 ° C, preferably 245 to 265 ° C, and a pressure of 0.2 to 3 kg / cm.²G, preferably 0.5-2kg / cm²The esterification reaction in the final stage is usually performed at a reaction temperature of 250 to 280 ° C, preferably 255 to 275 ° C, and a pressure of 0 to 1.5 kg / cm.²G, preferably 0-1.3kg / cm²Performed under G conditions.
[0032]
  When the esterification reaction is carried out in two stages, the esterification reaction conditions of the first stage and the second stage are within the above ranges, respectively, and when carried out in three stages or more, the second stage The esterification reaction conditions up to one stage before the last stage may be any conditions between the reaction conditions of the first stage and the reaction conditions of the last stage.
[0033]
  For example, when the esterification reaction is carried out in three stages, the reaction temperature of the second stage esterification reaction is usually 245 to 275 ° C, preferably 250 to 270 ° C, and the pressure is usually 0 to 2 kg / cm²G, preferably 0.2-1.5kg / cm²G is all right.
[0034]
  Although the esterification reaction rate in each of these stages is not particularly limited, it is preferable that the degree of increase in the esterification reaction rate in each stage is smoothly distributed, and further in the esterification reaction product in the final stage. Usually, it is desirable to reach 90% or more, preferably 93% or more.
[0035]
  By this esterification step, an esterified product (low-order condensate) of an aromatic dicarboxylic acid and an aliphatic diol is obtained, and the number-average molecular weight of this low-order condensate is about 500 to 5,000.
[0036]
  Such esterification reaction is not limited to raw materials such as aromatic dicarboxylic acids and aliphatic diols, but also tertiary amines such as triethylamine, tri-n-butylamine, and benzyldimethylamine, tetraethylammonium hydroxide, tetra-n hydroxide. -Add quaternary ammonium hydroxide such as butylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-butylammonium hydroxide, trimethylbenzylammonium hydroxide, and basic compounds such as lithium carbonate, sodium carbonate, potassium carbonate, sodium acetate It may also be carried out in the presence of a polycondensation catalyst described later.
[0037]
  When, for example, an aromatic dicarboxylic acid and an aliphatic diol are esterified in the presence of such a basic compound, a polyester having a small content of dioxyethylene terephthalate component units can be obtained.
[0038]
  The low-order condensate obtained in the esterification step as described above is then supplied to the polycondensation (liquid phase polycondensation) step.
[Liquid phase polycondensation process]
  In the liquid phase polycondensation step, in the presence of the polycondensation catalyst, the low-order condensate obtained in the esterification step is reduced to a temperature not lower than the melting point of the polyester (usually 250 to 280 ° C.). The polycondensation is carried out by heating. The polycondensation reaction is desirably performed while distilling off unreacted aliphatic diol out of the reaction system.
[0039]
  The polycondensation reaction may be performed in one stage or may be performed in a plurality of stages. For example, when the polycondensation reaction is performed in a plurality of stages, the first stage polycondensation reaction is performed under the conditions of a reaction temperature of 250 to 290 ° C, preferably 260 to 280 ° C, a pressure of 500 to 20 torr, preferably 200 to 30 torr. The final stage polycondensation reaction is carried out under conditions of a reaction temperature of 265 to 300 ° C, preferably 270 to 295 ° C, and a pressure of 10 to 0.1 torr, preferably 5 to 0.5 torr.
[0040]
  When the polycondensation reaction is carried out in three stages or more, the polycondensation reaction from the second stage to the first stage before the last stage is performed between the reaction conditions of the first stage and the final stage. It is performed under the conditions of For example, when the polycondensation process is performed in three stages, the second stage polycondensation reaction is usually performed at a reaction temperature of 260 to 295 ° C, preferably 270 to 285 ° C, and a pressure of 50 to 2 torr, preferably 40 Performed under ~ 5torr condition.
[0041]
  In such a polycondensation reaction, as described above, the polycondensation catalyst is 0.001 to 0.2 mol%, preferably (i) germanium compound, in terms of metal atoms in the polycondensation catalyst, with respect to the aromatic dicarboxylic acid. 0.002 to 0.1 mol%, (ii) at least one compound selected from aluminum compounds, barium compounds, cobalt compounds, magnesium compounds, manganese compounds, strontium compounds, zinc compounds and phosphorus compounds is 0.005 to 0.3 mol%, preferably It is desirable to be contained in an amount of 0.010 to 0.2 mol%.
[0042]
  Such a polycondensation catalyst may be present during the polycondensation reaction. For this reason, the polycondensation catalyst may be added in the esterification step or in the liquid phase polycondensation step. The polycondensation reaction is desirably performed in the presence of a stabilizer. Specific stabilizers include phosphate esters such as trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, trioctyl phosphate, triphenyl phosphate, triphenyl phosphite, trisdodecyl phosphite, trisnonyl phenyl phosphite. Phosphites such as methyl acid phosphate, ethyl acid phosphate, isopropyl acid phosphate, butyl acid phosphate, dibutyl phosphate, monobutyl phosphate, dioctyl phosphate, etc. and phosphoric compounds such as phosphoric acid, polyphosphoric acid, etc. It is done.
[0043]
  The addition amount of such a phosphorus compound is 0.005 to 0.2 mol%, preferably 0.01 to 0.1 mol%, in terms of phosphorus atom in the phosphorus compound, with respect to the aromatic dicarboxylic acid.
[0044]
  The intrinsic viscosity [IV] of the polyester obtained by the liquid phase polycondensation process as described above is 0.40 to 1.0 dl / g, preferably 0.50 to 0.90 dl / g. In addition, although the intrinsic viscosity achieved in each stage except the final stage of this liquid phase polycondensation process is not particularly limited, it is preferable that the degree of increase in intrinsic viscosity in each stage is smoothly distributed.
[0045]
  In the present specification, the intrinsic viscosity [IV] is calculated from the solution viscosity measured at 25 ° C. after cooling and dissolving 1.2 g of polyester in 15 cc of o-chlorophenol.
[0046]
  The polyester obtained in this liquid phase polycondensation step is usually melt extruded and formed into granules (chips).
[Solid phase polycondensation process]
  The polyester obtained in this liquid phase polycondensation step may be further subjected to solid phase polycondensation if desired.
[0047]
  The granular polyester supplied to the solid phase polycondensation step may be preliminarily crystallized by heating to a temperature lower than the temperature at which solid phase polycondensation is performed, and then supplied to the solid phase polycondensation step.
[0048]
  Such precrystallization can be carried out by heating the granular polyester in a dry state to a temperature of usually 120 to 200 ° C., preferably 130 to 180 ° C. for 1 minute to 4 hours. Such precrystallization can also be performed by heating the granular polyester at a temperature of 120 to 200 ° C. for 1 minute or more in a steam atmosphere, a steam-containing inert gas atmosphere, or a steam-containing air atmosphere.
[0049]
  The precrystallized polyester desirably has a crystallinity of 20 to 50%.
[0050]
  In this precrystallization treatment, the so-called polyester solid phase polycondensation reaction does not proceed, and the intrinsic viscosity of the precrystallized polyester is almost the same as the intrinsic viscosity of the polyester after liquid phase polycondensation, The difference between the intrinsic viscosity of the pre-crystallized polyester and the intrinsic viscosity of the polyester before pre-crystallization is usually 0.06 dl / g or less.
[0051]
  The solid phase polycondensation step comprises at least one stage, the temperature is 190 to 230 ° C, preferably 195 to 225 ° C, and the pressure is 1 kg / cm.²The reaction is carried out under a condition of G to 10 Torr, preferably from normal pressure to 100 Torr, in an inert gas atmosphere such as nitrogen, argon, carbon dioxide. Nitrogen gas is desirable as the inert gas used.
[0052]
  The granular polyester obtained through such a solid phase polycondensation step may be subjected to water treatment by, for example, the method described in JP-B-7-64920. It is carried out by contacting with a steam-containing inert gas, steam-containing air or the like.
[0053]
  The intrinsic viscosity of the granular polyester thus obtained is usually 0.60 to 1.00 dl / g, preferably 0.75 to 0.95 dl / g.
[0054]
  In addition, the polyester obtained by the method of the present invention may be blended with a conventionally known additive, for example, a stabilizer, a release agent, an antistatic agent, a dispersant, a dye, and a coloring agent, if desired, and melt-molded. Used for bottles, sheets, films, etc.
[0055]
【The invention's effect】
  According to the method for producing a polyester according to the present invention, the polycondensation reaction can be completed in a short time compared to the case where the germanium compound catalyst is used alone. Further, since the amount of germanium compound used as the catalyst can be reduced, the production cost of the polyester can be reduced.
[0056]
【Example】
  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.
[0057]
[Reference example1]
  A low-order condensate of ethylene glycol and terephthalic acid was continuously produced as follows.
[0058]
  In a reactor in which 33500 parts by weight of the reaction liquid (during steady operation) stays in advance, 260 ° C. and 0.9 kg / cm in a nitrogen atmosphere with stirring²Under the conditions maintained at G, a slurry prepared by mixing 6458 parts by weight of high-purity terephthalic acid and 2615 parts by weight of an aliphatic diol was continuously fed to conduct an esterification reaction. It was. In this esterification reaction, a mixed solution of water and ethylene glycol was distilled off.
[0059]
  The esterification reaction product (low-order condensate) was continuously extracted from the system while controlling the average residence time to be 3.5 hours. The number average molecular weight of the low-order condensate of ethylene glycol and terephthalic acid obtained above was 600 to 1300 (3 to 5 mer).
[0060]
  A polycondensation catalyst was added to the low-order condensate thus obtained to perform a liquid phase polycondensation reaction. As the polycondensation catalyst, germanium dioxide and barium acetate were used, which were dissolved in ethylene glycol and added.
[0061]
  As catalyst addition amounts, germanium dioxide is added in an amount of 0.021 mol% in terms of germanium atoms and 0.042 mol% in terms of barium acetate with respect to the terephthalic acid unit in the low-order condensate. Furthermore, MAP (mixture of monomethyl phosphate and dimethyl ester) in terms of phosphorus atoms. An amount of 042 mol% was added, and a polycondensation reaction was carried out under the conditions of 285 ° C. and 1 torr.
[0062]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0063]
[Reference example2]
  Except for changing the addition amount of germanium dioxide to 0.0105 mol%Reference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0064]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0065]
[Reference example3]
  Except for changing the amount of barium acetate added to 0.021 mol%Reference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0066]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0067]
[Comparative Example 1]
  Except that barium acetate was not added and only germanium dioxide was used as a catalyst for polycondensationReference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0068]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0069]
[Comparative Example 2]
  A polycondensation reaction was performed in the same manner as in Comparative Example 1 except that 0.021 mol% of the amount of germanium dioxide added was changed to 0.0105 mol%.
[0070]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0071]
【Example1]
  Reference example 1In this case, germanium dioxide and aluminum acetate are used as the polycondensation catalyst, and the amount of catalyst added is 0.021 mol% acetic acid with respect to the terephthalic acid unit in the low-order condensate as germanium dioxide in terms of germanium atoms. A polycondensation reaction was carried out in the same manner as in Example 1 except that aluminum was added in an amount of 0.042 mol% in terms of aluminum atoms.
[0072]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0073]
【Example2]
  Example1In Example, except that the addition amount of germanium dioxide was changed to 0.0105 mol%1The polycondensation reaction was performed in the same manner as described above.
[0074]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0075]
【Example3]
  Example1In Example, except that the addition amount of aluminum acetate was changed to 0.021 mol%1The polycondensation reaction was performed in the same manner as described above.
[0076]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0077]
[Reference example 4]
  Reference example1, germanium dioxide and cobalt acetate are used as the polycondensation catalyst, and the amount of catalyst added is 0.021 mol% in terms of germanium atoms with respect to the terephthalic acid unit in the low-order condensate, acetic acid. Except for changing cobalt to 0.042 mol% in terms of cobalt atomReference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0078]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0079]
[Reference Example 5]
  Except for changing the addition amount of germanium dioxide to 0.0105 mol%Reference example 4The polycondensation reaction was performed in the same manner as described above.
[0080]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0081]
[Reference Example 6]
  Except for changing the amount of cobalt acetate added to 0.021 mol%Reference example 4The polycondensation reaction was performed in the same manner as described above.
[0082]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0083]
[Reference Example 7]
  Reference example 1In this case, germanium dioxide and magnesium acetate are used as the polycondensation catalyst, and the amount of catalyst added is 0.021 mol% of germanium dioxide in terms of germanium atoms with respect to the terephthalic acid unit in the low-order condensate, magnesium acetate. Except that the magnesium atom is 0.042 mol% in terms of magnesium atomReference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0084]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0085]
[Reference Example 8]
  Except for changing the addition amount of germanium dioxide to 0.0105 mol%Reference Example 7The polycondensation reaction was performed in the same manner as described above.
[0086]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0087]
[Reference Example 9]
  Except for changing the amount of magnesium acetate added to 0.021 mol%Reference Example 7The polycondensation reaction was performed in the same manner as described above.
[0088]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0089]
[Reference Example 10]
  Reference example1, germanium dioxide and manganese acetate are used as a polycondensation catalyst, and the amount of catalyst added is 0.021 mol% in terms of germanium atoms, acetic acid, with respect to the terephthalic acid unit in the low-order condensate. Except that manganese is 0.042 mol% in terms of manganese atomReference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0090]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0091]
[Reference Example 11]
  Except for changing the addition amount of germanium dioxide to 0.0105 mol%Reference Example 10The polycondensation reaction was performed in the same manner as described above.
[0092]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0093]
[Reference Example 12]
  Except for changing the amount of manganese acetate added to 0.021 mol%Reference Example 10The polycondensation reaction was performed in the same manner as described above.
[0094]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0095]
[Reference Example 13]
  Reference example1, germanium dioxide and strontium acetate are used as the polycondensation catalyst, and the amount of catalyst added is 0.021 mol% of germanium dioxide in terms of germanium atom, acetic acid, with respect to the terephthalic acid unit in the low-order condensate. Except for changing strontium to 0.042 mol% in terms of strontium atomsReference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0096]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0097]
[Reference Example 14]
  Except for changing the addition amount of germanium dioxide to 0.0105 mol%Reference Example 13The polycondensation reaction was performed in the same manner as described above.
[0098]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0099]
[Reference Example 15]
  Except for changing the amount of strontium acetate added to 0.021 mol%Reference Example 13The polycondensation reaction was performed in the same manner as described above.
[0100]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0101]
[Reference Example 16]
  Reference example1, germanium dioxide and zinc acetate are used as the polycondensation catalyst, and the amount of catalyst added is 0.021 mol% in terms of germanium atoms, acetic acid, with respect to the terephthalic acid unit in the low-order condensate. Except that zinc was 0.042 mol% in terms of zinc atomReference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0102]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0103]
[Reference Example 17]
  Except for changing the addition amount of germanium dioxide to 0.0105 mol%Reference Example 16The polycondensation reaction was performed in the same manner as described above.
[0104]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0105]
[Reference Example 18]
  Except for changing the amount of zinc acetate added to 0.021 mol%Reference Example 16The polycondensation reaction was performed in the same manner as described above.
[0106]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0107]
[Reference Example 19]
  Reference example1, germanium dioxide and sodium dihydrogen phosphate are used as the polycondensation catalyst, and the amount of catalyst added is 0.021 mol in terms of germanium atoms with respect to the terephthalic acid unit in the low-order condensate. %, Except that sodium dihydrogen phosphate was 0.042 mol% in terms of sodium atomReference exampleThe polycondensation reaction was carried out in the same manner as in 1.
[0108]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0109]
[Reference Example 20]
  Except for changing the addition amount of germanium dioxide to 0.0105 mol%Reference Example 19The polycondensation reaction was performed in the same manner as described above.
[0110]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0111]
[Reference Example 21]
  Except for changing the addition amount of sodium dihydrogen phosphate to 0.021 mol%Reference Example 19The polycondensation reaction was performed in the same manner as described above.
[0112]
  Table 1 shows the time (liquid weight time) required for the intrinsic viscosity [IV] of polyethylene terephthalate to reach 0.56 dl / g.
[0113]
[Table 1]

Claims (3)

(I) a germanium compound as a polycondensation catalyst in the production of a polyester by polycondensation of an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol or an ester-forming derivative thereof in the presence of a polycondensation catalyst And (ii) a method for producing a polyester, comprising using a catalyst comprising an aluminum compound selected from aluminum acetate, aluminum carbonate, and aluminum acetylacetonate .   The method for producing a polyester according to claim 1, wherein aluminum acetate or aluminum carbonate is used as the aluminum compound.   The method for producing a polyester according to claim 1, wherein germanium dioxide is used as the germanium compound.