JPH02632A - Polyethylene terephthalate and its use - Google Patents

Abstract

PURPOSE:To obtain polyethylene terephthalate improved in heat resistance and transparency and being useful for a preform for blow moldings and a blow- molded container by specifying the composition and properties of the polyethylene terephthalate. CONSTITUTION:For example, terephthalic acid is esterified with ethylene glycol, and the product is polycondensed to obtain polyethylene terephthalate having a composition composed of randomly arranged 97.0-98.6mol% ethylene terephthalate component units of formula I and 1.4-3.0mol% dioxyethylene terephthalate component units of formula II and having an intrinsic viscosity [eta]in o-chlorophenol of 0.70-0.90dl/g (at 25 deg.C), a crystallization temperature (Tcc) >=165.0 deg.C as determined by differential scanning calorimetry (with the rate of temperature rise of 10 deg.C/min) and in the range: 67.5 [eta]+119.0<=Tcc<=67.5[eta]+133.5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to polyethylene terephthalate having excellent heat resistance and transparency. The present invention also relates to a preform for a blow-molded object and a blow-molded container made of the polyethylene terephthalate and having excellent heat resistance and transparency, and particularly to a blow-molded container made of heat-resistant polyethylene terephthalate and having excellent high-temperature filling properties.

Glass has been widely used as a material for containers for seasonings, oils, juices, carbonated drinks, beer, sake, cosmetics, detergents, etc. However, since glass containers are expensive to manufacture, a method is generally adopted in which empty containers are collected after use and reused. In addition, glass containers are heavy, which increases shipping costs, and they also have drawbacks such as being easily damaged and inconvenient to handle.

In an attempt to eliminate these drawbacks of glass containers, there has recently been a rapid shift from glass containers to various plastic containers. Various plastics are used as materials depending on the type of contents and the purpose of use. Among these plastic materials, polyethylene terephthalate has excellent mechanical strength, heat resistance, transparency, and gas barrier properties. Because of its excellent properties, it is used as a base for containers for juices, soft drinks, carbonated drinks, seasonings, detergents, cosmetics, etc. Also, among these uses,
Blow-molded containers for filling juices, soft drinks, and carbonated drinks are required to be sterilized and filled at high speed, and for this reason, it is required that the blow-molded containers be made of heat-resistant resin that can withstand high-temperature filling. Furthermore, all of these blow-molded containers for filling are required to be transparent.

Polyethylene terephthalate is a plastic excellent in these physical properties, but polyethylene terephthalate 1-- which simultaneously has heat resistance and transparency that can withstand the above-mentioned high-temperature filling properties - has not been known so far.

Therefore, conventional methods for molding heat-resistant blow-molded containers from polyethylene terephthalate include laminating heat-resistant resins such as polyarylate (Flastix, V
ol, 36 (No. 9), 121 (1985), etc.)
, method of applying heat setting after molding (Special Publication No. 59-33
No. 01, JP-A-55-12031, JP-A-Sho 5
6-75833, JP-A-56-13142, etc.), and a method of improving the degree of crystallinity by treating the molded container with a solvent (Japanese Patent Publication No. 59-15807, etc.) has been proposed. All of these methods attempt to impart heat resistance to polyethylene terephthalate, which originally has insufficient ηI thermal properties, by means of molding or post-molding treatment, but the blow-molded containers obtained by any of these methods also Polyethylene terephthalate, which has excellent heat resistance and transparency that can withstand the temperature, pressure, and liquid weight during high-temperature filling, does not satisfy the heat resistance and transparency during high-temperature filling, and from such polyethylene terephthalate. There is a strong demand for a preform for a hollow molded body and a blow molded container.

The present invention has been completed in view of the above-mentioned situation with conventional polyethylene terephthalate and blow-molded containers made of polyethylene terephthalate, and is a blow-molded container that has excellent heat resistance and transparency at the same time. The purpose is to provide polyethylene terephthalate for containers. Furthermore, the present invention provides a preform for a hollow molded body formed from polyethylene terephthalate, which has excellent heat resistance and transparency, and has particularly excellent heat resistance during high-temperature filling of juices, soft drinks, carbonated drinks, etc. and a blow-molded container.

According to the present invention, the ethylene terephthalate component unit fa) represented by (^)-formula [I] is in the range of 97.0 to 98.6 mol% and represented by the general formula [■] Dioxyethylene terephthalate component unit [b) is formed in a range of 1.4 to 3.0 mol%,
and the image component units are randomly arranged, (B) the intrinsic viscosity [η] measured in 0-chlorophenol at 25°C is in the range of 0.70 to 0.90 dll/g, and C) The crystallization temperature ('rcc) measured with a differential scanning calorimeter (DSC) at a heating rate of 10"C/min is 165.0°C.
or more, and 67.5 [η ko + 119.0 ≦Tcc≦67
．． Polyethylene terephthalate is provided which is characterized by being in the range expressed by 5[η]+133.5, and a preform for a blow molded article and a blow molded container molded from the polyethylene terephthalate are provided.

According to the present invention, the ethylene terephthalate component unit (a) represented by the formula (A) - [Iko→ooc+cooc++ c+++...[I] is 9
The dioxyethylene terephthalate component unit (b) represented by the general formula [1] % formula % [[] is formed from a range of 1.4 to 3.0 mol%. is,
and the image component units are arranged randomly, (B) the intrinsic viscosity [η] determined by clear I in o-chlorophenol at 25°C is in the range of 0.70 to 0.90 dJI/, (C) The crystallization temperature (Tcc) measured with a differential scanning calorimeter (DSC) at a heating rate of lo'c/min is 165,0°
C or higher, and 67.5 [77] + 119.0≦Tcc≦67.5 [
η]+133.5, and (D) the number fa) of spherulites produced when isothermally crystallized at 200°C after melting at 290°C is 108/M or less; The difference between the number of spherulites (a) and the number of spherulites produced when isothermally crystallized at 200°C after melting at 280'C ((b) - (a)) is 5X 107 Individual/
1 by being less than or equal to M? The present invention provides polyethylene terephthalate characterized by the above characteristics, and also provides a preform for a blow molded article and a blow molded container molded from the polyethylene terephthalate.

The polyethylene terephthalate of the present invention has the -fi formula [I
] The content of the ethylene terephthalate component unit (a) is 97.0 to 98.6 mol%, 97.1 to 98
．． 5 mol%, particularly preferably 97.3 to 98.3 mol%
- The content of the dioxyethylene terephthalate component unit (b) represented by the formula [[] is 1.4 to 3.0 mol%, preferably 1
．． The range is 5 to 2.9 mol%, particularly preferably 1.7 to 2.7 mol%.

The polyethylene terephthalate of the present invention has the above-mentioned formula [I
] Ethylene terephthalate component unit (a)
The dioxyethylene terephthalate component units (b) represented by formula [II] are arranged randomly to form ester bonds, thereby forming a substantially linear polyester. The fact that the polyethylene terephthalate is substantially linear is confirmed by dissolving the polyethylene terephthalate in O-chlorophenol.

The intrinsic viscosity of the polyethylene terephthalate of the present invention measured in 0-chlorophenol at 25°C [η is 0.7
0-0.90 dJ/ preferably 0.71-0.8
7 dJ/f, particularly preferably 0.72 to 0.85 dJ
It is in the range of l/lr. Intrinsic viscosity [η] is 0.70d
, 117g, it is impossible to obtain a blow-molded container with good heat resistance, transparency and mechanical strength, and when it is larger than 0.90dJl/g, the moldability and stretch-blow moldability of the preform deteriorate. become inferior. Note that the specific intrinsic viscosity [η] of the polyethylene terephthalate of the present invention was measured by the following method. That is, sample polyethylene terephthalate was dissolved in O-chlorophenol at a concentration of Ig/100ml, the solution viscosity was measured using an Ubbelohde capillary viscometer at room temperature, and then O-chlorophenol was gradually added to The solution viscosity on the concentration side was measured and extrapolated to 0% concentration to determine the solution viscosity ([η]).

Further, the heated crystallization temperature (TCC) of the polyethylene terephthalate of the present invention when heated at a rate of 10° C./min using a differential scanning calorimeter (DSC) is 165.0° C. or higher, preferably 167° C. It is in the range of .0 to 185°C, particularly preferably 168.0 to 180.0°C. Further, the elevated crystallization temperature (Tc) of the polyethylene terephthalate of the present invention
c) is within the range of the following formula % in relation to the intrinsic viscosity [η], more preferably 67.5[η]+122.5≦Tcc≦67.5[η]+128.5. in range.

Elevated crystallization temperature (Tc) of the polyethylene terephthalate
If c) is lower than 165.0°C, the transparency of the blow-molded container will decrease, the heat resistance will also decrease, and thermal deformation will occur when filling soft drinks such as juice or cola at high temperature. Furthermore, if the elevated temperature crystallization temperature (Tcc) is lower than the lower limit of the above formula, thermal deformation is likely to occur similarly when filling a soft drink such as juice or cola at a high temperature. Note that the elevated temperature crystallization temperature ('rcc) that specifies the polyethylene terephthalate of the present invention is measured by the following method. That is, using a PerkinElmer Model DSC-2 differential scanning calorimeter, a thin piece of about 10 IWIt of a sample from the center of a polyethylene terephthalate chip that had been dried at about 140° C. under a pressure of about 5 tram HQ for about 5 hours or more was heated using a PerkinElmer DSC-2 differential scanning calorimeter. The measurement was carried out by enclosing the sample in an aluminum pan under a nitrogen atmosphere. The measurement conditions are: First, the temperature is rapidly raised from room temperature, melted and held at 290°C for 10 minutes, then rapidly cooled to room temperature, and then the peak temperature of the exothermic peak detected when the temperature is raised at a rate of 10°C/min. I asked for

Furthermore, from the polyethylene terephthalate of the present invention, 28
Haze (H
aze, irritability) is usually 2 to 15%, preferably 3
-10%, particularly preferably 3-7%. Further, the haze of the polyethylene terephthalate of the present invention is in the range of the following formula % in relation to the intrinsic viscosity [η], more preferably 220 [77] + 170≦[Hazel≦-220 [
η]+174. Note that the haze of polyethylene terephthalate was measured according to the following method. That is, approximately 140
Polyethylene terephthalate dried at a temperature of about 5 tm HQ for more than about 16 hours at a temperature of about 2.3
．． 4.5.6.7 Thickness plates can be molded at the same time using a stepped square plate mold manufactured by Tsumakira Aji at a cylinder temperature of 26.
Injection molding was carried out under the conditions of 0 to 275°C1 mold temperature of approximately 40°C, and the haze of the resulting stepped square plate with a thickness of 5rm was measured using an HM-100 type haze meter manufactured by Murakami Color ■. did.

In addition, the polyethylene terephthalate of the present invention has 290
The number fa of spherulites produced when isothermally crystallized at 200°C after melting in
7 pieces/rrl or less. The difference between the number of spherulites (a) and the number of spherulites produced when isothermally crystallized at 200°C after melting at 280'C ((b) - (a
)) is 5 x 107 cells/ml or less, preferably 3 x 107
It is preferably 1×10 7 pieces/rrl or less, particularly preferably 1×10 7 pieces/rrl or less.

The number of spherulites was determined by measuring the polyethylene terephthalate of the present invention at 290°C or 28°C using a differential scanning calorimeter (DSC).
After melting at 0°C, the temperature was lowered to 200°C at a rate of 320°C/min, and the resulting spherulites were crystallized at 200°C for 0.5 hours. Measure the average size of the crystal, then F, Van, ^nt
Verpen, D, 14. The method of Van, Krevelan et al. [J, Polyn+, Sci, Polym, P
hys, Ed., 10°2423 (1972)], the number of spherulites N=1/[<4/3)πR3] (R: average radius of spherulites).

If the number (a) of spherulites when melted at 290°C and then isothermally crystallized at 200°C is 108/rr1 or more, the transparency of the preform or blow-molded container obtained from such polyethylene terephthalate will be improved. tends to get worse. Also, the difference between the number of spherulites (a) and the number of spherulites (b) when crystallized at 200°C after melting at 280°C < (b) - (a)) is 5 x 107 /rd or more, the transparency of preforms or blow-molded containers obtained from such polyethylene terephthalate similarly deteriorates.

In addition, when measuring the number of spherulites, the measurement sample is a thin slice of I Q nm g obtained from the center of a polyethylene terephthalate chip that has been dried at 140° C. under a pressure of about 51iIIIHg for about 5 hours or more. Use, D
A differential scanning calorimeter, DSC-2 manufactured by PerkinElmer, was used as the SC. The sample was sealed in a liquid aluminum pan under a nitrogen atmosphere and melted, and then cooled to a predetermined temperature to crystallize. Melting is 280°C and 290°
This was carried out by maintaining the melt at C for 10 minutes. Spherulite observation was performed by preparing a 10 μm thick thin section using a microtome and observing it at 300x magnification using a polarizing microscope manufactured by Nikon.

Next, the method for producing polyethylene terephthalate of the present invention will be explained.

The polyethylene terephthalate of the present invention can be produced by a direct polymerization method. Specifically, a mixture of terephthalic acid and ethylene glycol is continuously reacted in at least two esterification reaction steps to obtain a lower-order condensate, which is then continuously reacted in at least two liquid phase polycondensation steps. obtaining a polyester by polycondensation under reduced pressure; forming polyester chips from the polyester by melt extrusion; polycondensing the polyester chips in at least one solid phase polymerization step in an inert gas atmosphere; A method of increasing the limiting viscosity [η] is adopted.

Next, each step and its conditions will be explained.

The polyethylene terephthalate of the present invention is produced by appropriately selecting the conditions of each step so that (A) the composition of the polyethylene terephthalate, (B) the i limiting viscosity [η], and (C) the number of spherulites fall within the range specified by the present invention. It can be obtained by controlling the polycondensation reaction as follows.

First, terephthalic acid and 1 mole of terephthalic acid
．． An ethylene glycol slurry of terephthalic acid is formed from a mixture of 0.2 to 1.4 moles, preferably 1.03 to 1.3 moles of ethylene glycol. The slurry is continuously fed to the esterification reaction step. The esterification reaction is carried out using an apparatus in which at least two esterification reactors are connected in series, under conditions where ethylene glycol is refluxed, and water produced by the reaction is removed from the system in a rectification column. . The reaction conditions for carrying out the esterification reaction are such that the temperature of the first stage esterification reaction is usually 24°C.
0 to 270°C, preferably 245 to 265°C, and the pressure is usually 0.2 to 3 kg/aaG, preferably 0.5
~2 kg/clG, and the temperature of the final stage esterification reaction is usually 250-280°C, preferably 255-280°C.
The temperature is 75℃, and the pressure is usually 0 to 1.5 klr/aa.
G is preferably 0 to 1.3 kg/aaG. Therefore, when carrying out the esterification reaction in two stages,
When the esterification reaction conditions of the first stage and the second stage are within the above ranges, and the reaction is carried out in three or more stages,
The reaction conditions for the esterification reaction from the second stage to one stage before the final stage are between the reaction conditions for the first stage and the reaction conditions for the final stage. For example, when the esterification reaction is carried out in three stages, the reaction temperature of the second stage esterification reaction is usually 245-275°C, preferably 250-275°C.
70℃, and the pressure is usually 0-2 k+r/ad
G is preferably 0.2 to 1.5 kIr/ciG. The reaction rate of these esterification reactions is not particularly limited in each stage, but it is preferable that the increase and degree of esterification reaction rate in each stage is smoothly distributed, and furthermore, in the final stage of esterification. In the reaction product, a lower condensate is obtained by these esterification steps, which is usually 90% or more, preferably 93% or more, and the number average molecular weight of the low condensate is usually 500 to 5000. It is.

The low-order condensate thus obtained is continuously supplied to a polycondensation reactor for the next liquid phase polycondensation step. Regarding the reaction conditions of the polycondensation reaction, the reaction temperature of the first stage polycondensation is usually
260-290°C, preferably 265-290°C, more preferably 270-285°C, and the pressure is usually 500°C.
-20 Torr, preferably 200-30 Torr, and the temperature of the final stage polycondensation reaction is usually 270-300 Torr.
°C preferably 275-295 °C, and the pressure is usually
10-0, I Torr preferably 5-0.5T
It is orr.

In particular, when the reaction temperature of the first stage polycondensation is 265 to 285°C, the polyethylene terephthalate obtained is
The number of spherulites (a) produced when isothermally crystallized at 200°C after melting at 90°C is 108 or less, and the number of spherulites (a) and 200 after melting at 280°C "C.
Polyethylene terephthalate can be obtained in which the difference ((b) - (a)) from R(b) of spherulites produced when crystallized isothermally is 5×10′/M or less.

When the polycondensation reaction is carried out in two stages, the polycondensation reaction conditions for the first stage and the second stage are within the above ranges, and when the polycondensation reaction is carried out in three or more stages, from the second stage The reaction conditions for the polycondensation reaction up to one stage before the final stage are between the reaction conditions for the first stage and the reaction conditions for the final stage. For example, if the polycondensation reaction is carried out in three stages, the second
The reaction temperature of the polycondensation reaction in the second step is usually 265-295°C, preferably 270-290°C, more preferably 270-295°C.
The temperature is 85° C. and the pressure is usually in the range of 50 to 2 Torr, preferably 40 to 5 Torr.

There is no particular limit to the intrinsic viscosity [η] reached in each of these polycondensation reaction steps, but it is preferable that the degree of increase in the intrinsic viscosity in each stage is distributed smoothly, and that The intrinsic viscosity [η] of polyethylene terephthalate obtained from the reactor is usually 0.55 to
0.70dj/g preferably 0557-0.68dJ/
The range is r. The polyethylene terephthalate thus obtained from the final polycondensation reactor is formed into chips by melt extrusion.

Furthermore, the polyethylene terephthalate chips are fed to an in-phase polycondensation process. The solid phase polycondensation process consists of at least one stage, the polycondensation temperature is usually 190 to 230°C, preferably 195 to 225°C, and the pressure is usually 1 k
g/ciG ~10 Torr preferably normal pressure to 1
The solid phase polycondensation reaction is carried out under conditions of 0.00 Torr and in an inert gas atmosphere such as nitrogen gas, argon gas, carbon dioxide gas, etc. Among these inert gases, nitrogen gas is preferred.

The above-mentioned esterification reaction can be carried out without adding any additives other than terephthalic acid and ethylene glycol, and it can also be carried out in the presence of a polycondensation catalyst (which will be described later). Tertiary amines such as triethylamine, tri-n-butylamine, benzyldimethylamine, etc.
amine, quaternary ammonium hydroxide such as tetraethylammonium hydroxide, tetra-n-butylammonium hydroxide, and trimethylbenzylammonium hydroxide, and basic compounds such as lithium carbonate, sodium carbonate, potassium carbonate, and sodium acetate. It is preferable to carry out this method because the proportion of dioxyethylene terephthalate component units in the main chain of polyethylene terephthalate can be maintained at a relatively low level.

There are no particular restrictions on the method of adding these base component unit compounds, and they may be added to all of the esterification reactors, or they may be added to a specific reactor in the first stage or second stage or later. good. Further, the polycondensation reaction is preferably carried out in the presence of a catalyst and a stabilizer. As a catalyst, germanium compounds such as germanium dioxide, germanium tetraethoxide, and germanium tetralobtoxide can be used. Among these catalysts, germanium dioxide compounds are preferred because the produced polyethylene terephthalate has excellent hue and transparency.
In addition, as stabilizers, trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, trioctyl phosphate, triphenyl phosphate,
Phosphate esters such as tricresyl phosphate, triphenyl phosphite, trisdodecyl phosphite,
Phosphite esters such as trisnonylphenyl phosphite, acidic phosphoric acid esters such as methyl arashido phosphate, isopropyl arashido phosphate, butyl arashido phosphate, dibutyl phosphate, monobutyl phosphate, dioctyl phosphate, phosphoric acid, polyphosphorus Phosphorus compounds such as acids are used. The proportion of these catalysts or stabilizers used is usually 0.0005 to 0.0005 to the weight of the metal in the catalyst relative to the weight of the mixture of terephthalic acid and ethylene glycol.
0.2% by weight, preferably in the range of 0.001 to 0.05% by weight, and in the case of a stabilizer, usually 0.001 to 0.1% by weight, based on the weight of phosphorus atoms in the stabilizer. is in the range of 0.002 to 0.02% by weight. These catalysts and stabilizers can be supplied at the stage of the esterification reaction process, or can be supplied to the first stage reactor of the polycondensation reaction process.

The preform for a hollow molded body of the present invention is obtained by molding the polyethylene terephthalate into a preform by a conventional method. It may be a preform for a molded body, or a multilayer preform for a multilayer hollow molded body formed from a layer made of the polyethylene terephthalate and a layer made of a resin other than polyethylene terephthalate such as a gas barrier resin. good.

The polyethylene terephthalate constituting the preform for the hollow molded body of the present invention may contain conventionally known nucleating agents, inorganic fillers, lubricants, slip agents, anti-blocking agents, stabilizers, antistatic agents, and preventive agents. Various additives such as agents, pigments, etc. may be appropriately blended. In addition, when the glyform for a hollow molded body of the present invention is a single-layer preform for a single-layer hollow molded body formed from the polyethylene terephthalate, the polyethylene terephthalate may further include conventionally known gas barrier
Resins other than polyethylene terephthalate, such as resins having properties, can also be blended, and the blending ratio is within an appropriate range.

The preform for a hollow molded body of the present invention can be molded by a conventionally known method. For example, a single layer preform can be molded by an injection molding method, and the multilayer preform can be molded by a multilayer injection molding method. It can also be manufactured by molding, or by a method of molding a tubular product having a similar 8I layer structure. In particular, when molding a preform by injection molding,
When the polyethylene terephthalate of the present invention is used, the air vent part of the mold becomes extremely less dirty and clogged during injection molding, making it possible to reduce the frequency of cleaning the mold, thereby greatly increasing the productivity of preform molding. can be improved.

The blow-molded container of the present invention is produced by stretch-blow molding the preform for a hollow-molded body. The blow-molded container of the present invention may be a single-layer blow-molded container made of the polyethylene terephthalate like the preform, or may be a single-layer blow-molded container made of the polyethylene terephthalate and a resin having gas barrier properties. It may also be a multilayer blow-molded container formed from layers made of a resin other than polyethylene terephthalate, such as polyethylene terephthalate.

When the blow-molded container of the present invention is a multilayer blow-molded container, the thickness of the container wall is mainly made of the polyethylene terephthalate, and a thin layer of resin other than polyethylene terephthalate, such as the resin having gas barrier properties, is used. The resin layer other than polyethyl terephthalate may be the outermost layer, the innermost layer, or an intermediate layer.

The polyethylene terephthalate constituting the blow-molded container of the present invention may contain conventionally known nucleating agents, inorganic fillers, lubricants, slip agents, anti-blocking agents, stabilizers, antistatic agents, antifogging agents, Appropriate amounts of various additives such as pigments may be blended, and when the blow-molded container of the present invention is a single layer container of the polyethylene terephthalate, the polyethylene terephthalate may further contain, if necessary, Resins other than polyethylene terephthalate, such as conventionally known resins having gas barrier properties, can also be blended, and the blending ratio is within an appropriate range.

The blow molded container of the present invention is usually stretched, and may be a -axially stretched blow molded container or a biaxially stretched blow molded container. When the blow-molded container is a uniaxially stretched blow-molded container, the stretching (+l+magnification) is usually
It is in the range of 1.1 to 10 times, preferably 1.2 to 8 times, particularly preferably 1.5 to 7 times, and in the case of a biaxially stretched blow-molded container, the stretching ratio is usually in the longitudinal direction. 1.1
~8 times, preferably 1,2 to 7 times, particularly preferably 1,5
In the horizontal axis direction, it is usually in the range of 1.1 to 8 times, preferably 1.2 to 7 times, particularly preferably 1.5 to 6 times.

In the production of the blow-molded container or blow-molded container,
Using the polyethylene terephthalate of the present invention, -
During axial stretch blow molding or biaxial stretch blow molding, the blow mold becomes much less dirty than before, and the frequency of cleaning the blow mold can be reduced. Productivity can be greatly improved.

The blow-molded container of the present invention is manufactured by stretch-blow molding the preform for a blow-molded body. Examples of this method include a method in which a heated preform is stretched in the longitudinal direction and then further stretched in the horizontal direction by blow molding. The heating temperature of the preform during blow molding is usually 80 to 130°C.
Preferably it is in the range of 85 to 125°C, and the blow molding mold temperature is usually room temperature to 200°C, preferably 40 to 18°C.
It is in the range of 0°C. Conventionally known methods are used for heat setting, and the heat setting temperature is usually in the range of 110 to 170°C, preferably 120 to 160°C.

[Example] Next, the present invention will be specifically explained using an actual repair example.

1, 2, 3, 4 and 5 as shown in Figure 1.
Using a continuous polycondensation apparatus consisting of a horizontal reactor in which the first reactor is horizontal and the sixth reactor is a biaxially rotating horizontal reactor, continuous polymerization was carried out as follows to produce polyethylene terephthalate. .

3,750 parts by weight of the reaction solution was stored in advance in the first reactor, which was maintained under stirring at 255°C under a nitrogen atmosphere at a rate of 1.7 kr/cJG.
A slurry prepared by mixing 437 parts by weight of ethylene glycol and 645 parts by weight of ethylene glycol was continuously fed to carry out the first stage esterification reaction. In this first stage esterification reaction, a mixed solution of 203 parts by weight of water and 3 parts by weight of ethylene glycol was distilled off. , t. This first stage esterification reaction product was controlled to have an average residence time of 2.0 hours, and was continuously stirred at 260°C at 0.
．． A second reactor was maintained under conditions of 8kr/cJG. In this reactor 2, a homogeneous solution of 0.35 parts by weight of germanium dioxide and 32 parts by weight of ethylene glycol is continuously supplied per hour, and 8 parts by weight of ethylene glycol are continuously supplied per hour.
The mixture of water and 7 parts by weight of ethylene glycol was continuously distilled off to continue the second stage esterification reaction. The second stage esterification reaction product was controlled to have an average residence time of 2.0 hours, and the third stage was maintained at 265°C and normal pressure under continuous stirring.
led to the reactor. In this third reactor, 1 hourly
．． A homogeneous solution containing 23 parts by weight of trimethyl phosphate and 22 parts by weight of ethylene glycol is continuously supplied, and a mixed solution of 21 parts by weight of water and 38 parts by weight of ethylene glycol is continuously supplied per hour. removed,
The third stage esterification reaction was continued.

This third stage esterification reaction product also has an average residence time of 2.
275°C under continuous stirring for 0 hours.
into a fourth reactor maintained at 70 nwHg. In this fourth reactor, a mixture of 62 parts by weight of ethylene glycol and 6 parts by weight of water was continuously distilled off per hour to carry out the first stage polycondensation reaction. The polycondensation reaction product in the first stage was controlled to have an average residence time of 1.0 hours, and was heated to 280°C with continuous stirring for 5 hours.
into a fifth reactor maintained at .

In this fifth reactor, a liquid mixture of 26 parts by weight of ethylene glycol and 3 parts by weight of water was continuously distilled off per hour to continue the second stage polycondensation reaction. In addition, the second stage polycondensation reaction product was controlled to have an average residence time of 1.0 hours, and was continuously heated at 282°C to 285°C for 1 hour.
．． The mixture was introduced into a sixth reactor, which was a horizontal twin-screw rotating reactor maintained under conditions of 8 mmHg to 2.5 imHQ.

In this sixth reactor, the reaction solution of 12 parts by weight of ethylene glycol and 1 part by weight of water was continuously distilled off per hour to continue the third stage polycondensation reaction. The polycondensation reaction product in the third stage is controlled to have an average residence time of 2.5 hours, and is continuously extracted in the form of a strand out of the reactor by a polyester extractor and immersed in water. The intrinsic viscosity [η] of one or more polyethylene terephthalates obtained by liquid phase polymerization, which was soaked and cooled and then cut into chips with a strand cutter, was 0.62 d when measured in O-chlorophenol at 25°C.
, Q/g, and the content of the dioxyethylene terephthalate component was 2.50 mol%.

Furthermore, the polyethylene terephthalate obtained by liquid phase polymerization is dried at about 140° C. for about 15 hours in a nitrogen atmosphere and crystallized, and then loaded into a basic solid phase polymerization vessel.
Solid phase polymerization was performed at 205° C. for 15 hours under a nitrogen atmosphere. 0 of the polyethylene terephthalate thus obtained
- Intrinsic viscosity [η
0.80d, 117g, the content of the dioxyethylene terephthalate component was 2.53 mol%, and the heating crystallization temperature Tcc was 174°C. In addition, the number of spherulites produced when isothermally crystallized at 200°C after melting at 290°C is 5 × 107 pieces/M, and this number and the number of spherulites formed at 200°C after melting at 280°C The difference from the number of spherulites produced in isothermal crystallization is 3 × 107
number/M.

Next, the polyethylene terephthalate produced by this solid phase polymerization was dried at about 140°C under a reduced pressure of about 5 am HQ for about 16 hours, and then
-2.3 each in one molding using a 3J injection molding machine.
4.5.6.7 The cylinder temperature is 260°C to 275° in a stepped square plate mold that can simultaneously form plates with a thickness of 7 cm.
C, and a stepped square plate was obtained by injection molding at a mold temperature of about 40°C. The haze of the obtained stepped square plate having a thickness of 5 mm was measured using an HM-100 haze meter manufactured by Murakami Color Co., Ltd., and found to be 4.8%.

In the solid phase polymerization of polyethylene terephthalate obtained by liquid phase polymerization in Example 1, homophase polymerization was carried out in the same manner as in Example 1, except that the polymerization conditions were as described in Table 1. Ta. The intrinsic viscosity [η], the content of the dioxyethylene terephthalate component, and the elevated crystallization temperature of the obtained polyethylene terephthalate were as shown in Table 1.

Further, stepped square plates were formed in the same manner as in Example 1, and the haze of the plates having a thickness of 5 In+ was measured. The results are shown in Table 1.

Inukamiguchi Kusho Figure 1, continuous liquid phase polymerization is carried out as follows using a device in which the first reactor is used and the outlet piping of the slurry pump is connected to the second reactor. Polyethylene terephthalate was produced.

14 parts of high-purity terephthalic acid was added per hour to a second reactor in which 3,757 parts of the reaction solution was stored in advance and maintained under conditions of 1.5 kg/- in a nitrogen atmosphere at 250°C with stirring.
A slurry prepared by mixing 37 parts of ethylene glycol and 645 parts of ethylene glycol was continuously fed to perform the first esterification reaction.

In this first stage esterification reaction, 196
A mixture of parts by weight of water and 3 parts by weight of ethylene glycol was distilled off. Further, the esterification reaction product in the first stage is controlled so that the average residence time is 2.0 hours,
It was led to a third reactor which was maintained under conditions of 0.8 kg/aa at 260° C. under continuous stirring. In this third reactor, 0.35 parts by weight of germanium dioxide and 3 parts by weight of germanium dioxide were added per hour.
A homogeneous solution of 2 parts by weight of ethylene glycol is continuously fed, and a mixture of 87 parts by weight of water and 7 parts by weight of ethylene glycol is continuously distilled off per hour.
The second stage esterification reaction was continued. The second stage esterification reaction product was controlled to have an average residence time of 2.0 hours, and was continuously introduced into a fourth reactor maintained at 265°C and normal pressure. It was written.

In this fourth reactor, a homogeneous solution in which 0.20 parts by weight of methyl aracid phosphate and 22 parts by weight of ethylene glycol were mixed is continuously supplied, and at the same time, 22 parts by weight of water and 40 parts by weight of water are supplied per hour. Part by weight of the mixture with ethylene glycol was continuously distilled off to continue the third stage esterification reaction. The esterification reaction product in the third stage was also controlled to have an average residence time of 2.0 hours, and was continuously led to the fifth reactor maintained at 277° C. and 50 nmHg under stirring.

In this fifth reactor, a first stage polycondensation reaction was carried out in which a mixed solution of 72 parts by weight of ethylene glycol and 5 parts by weight of water was continuously distilled off per hour. '&, this first stage polycondensation reaction product was controlled so that the average residence time was 2.0 hours, and was continuously heated at 282°C to 285°C for 1.5 hours with Ha~2, OwH (A sixth reactor was maintained under conditions of J.

In this sixth reactor, the second stage polycondensation reaction was continued in which a mixed solution of 26 parts by weight of ethylene glycol and 1 part by weight of water was continuously distilled off per hour. Further, the second stage polycondensation reaction product was controlled so that the average residence time was 2.8 hours, and was continuously extracted through the polyester extraction device in the same manner as in Example 1, and further cooled. It was then shredded into chips. The intrinsic viscosity [η] and dioxyethylene terephthalate component content of the polyethylene terephthalate obtained by this liquid phase polymerization were measured in the same manner as in Example 1, and the results were 0.62 dll/
+r and 2.54 mol%.

Furthermore, after drying the polyethylene terephthalate obtained by the liquid phase polymerization in the same manner as in Example 1, solid phase polymerization was further carried out using the same apparatus as in Example 1 under the same conditions. As a result, the intrinsic viscosity [η] of the obtained polyethylene terephthalate was 0°79dj,/g, and the dioxyethylene terephthalate component content was 2.55 mol%. The number of spherulites produced during isothermal crystallization (a) is 6 x 107 pieces/
M, and its heating crystallization temperature Tcc was 168°C. The difference between the number of spherulites (b) and (a) produced when isothermally crystallized at 200°C after melting at 280°C is 7X107
pieces/ml.

Next, the polyethylene terephthalate produced by this in-phase polymerization was dried in the same manner as in Example 1, and further, a stepped square plate was formed using the same apparatus as in Example 1 under the same conditions. The haze of the obtained stepped square plate having a thickness of 5 fins was measured in the same manner as in Example 1, and the result was 7.1%.

In Figure 1, the first, third, fourth, and sixth reactors are not used, and the outlet piping of the slurry pump is connected to the second reactor, and the outlet piping of the second reactor is connected to the first, third, fourth, and sixth reactors. Using an apparatus connected to the fifth reactor, polyethylene terephthalate was produced by carrying out an esterification reaction in the second reactor and a polycondensation reaction in the fifth reactor as described below.

A second reactor maintained under a nitrogen atmosphere of 1.5 kg/cj at 180'C was filled with a slurry prepared by mixing 2874 parts by weight of high purity terephthalic acid and 1235 parts by weight of ethylene glycol. and further 0.70
A homogeneous solution of parts by weight of germanium dioxide and 30 parts by weight of ethylene glycol was charged under stirring. Then, while maintaining the pressure at 1.5 +r/-, the temperature was raised to 255°C over about 30 minutes to initiate the esterification reaction. The esterification reaction was continued for 6.4 hours at 255° C. under a pressure of 1.51 qr/− while controlling the content of ethylene glycol in the distilled water to be 5% by weight or less. In this esterification reaction, a mixed solution of 605 parts by weight of water and 30 parts by weight of ethylene glycol was distilled off.

After the esterification reaction was completed, the pressure in the reactor was returned to normal pressure, and then 0.40 ffi parts of methyl aracid phosphate'
After adding a mixed solution of 24 parts by weight of ethylene glycol, the mixture was kept under stirring for about 15 minutes. The esterification reaction product was then transferred to a fifth reactor maintained at normal pressure in a nitrogen atmosphere at 260°C, and then stirred for about 1 hour.
It took a while to bring the temperature from room temperature to about 1 wa Hg, and then
In the zero polycondensation reaction, the temperature was raised to 75°C to start the polycondensation reaction, and the degree of vacuum was about III InH! 2 while holding it in J
The heating was carried out at 75°C for about 1.5 hours, and the temperature was further raised to 285°C for about 1 hour. In this polycondensation reaction, a mixed liquid of 157 parts by weight of ethylene glycol and 26 parts by weight of water was distilled off.

After the polycondensation reaction, the pressure in the reactor was returned to normal pressure with nitrogen, and then the mixture was extracted for about 25 minutes through a polyester extractor, cooled in the same manner as in Example 1, and then shredded into chips. The intrinsic viscosity [η] and dioxyethylene terephthalate component content of the polyethylene terephthalate obtained by this liquid phase polymerization were measured in the same manner as in Example 1, and were found to be 0161 dj/g and 2.57 mol%, respectively.

Furthermore, after drying the polyethylene terephthalate obtained by the liquid phase polymerization in the same manner as in Example 1, solid phase polymerization was further carried out using the same apparatus as in Example 1 under the same conditions. As a result, the intrinsic viscosity [η] of the obtained polyethylene terephthalate was 0.79 dj/g, the content of the dioxyethylene terephthalate component was 2,57 mol%, and the temperature-raising crystallization rate Tcc was 147 It was °C. After further melting at 290°C, the number of spherulites produced when crystallizing isothermally at 200°C (a) beam x 107 pieces/r
rl, and the difference between the number of spherulites (b) and (a) produced when isothermally crystallized at 200°C after melting at 280°C is 1.2
It was X108 pieces/rrl.

Next, the polyethylene terephthalate produced by this solid phase polymerization was dried in the same manner as in Example 1, and further, a stepped square plate was formed using the same apparatus as in Example 1 under the same conditions. The haze of the obtained stepped square plate having five thicknesses was measured in the same manner as in Example 1, and the result was 27%.

After drying the polyethylene terephthalate obtained by solid-state polymerization in Example 1 at about 140°C for about 15 hours in a nitrogen atmosphere, it was melted using an injection molding machine at a molding temperature of 280°C.
A molding pressure of 800 ℃ was applied to the preform mold cooled to 0℃.
Injection molded with +r/-, outer diameter 28cm, thickness 4IwwI
A preform was prepared. Next, only the spout part is 160
A preform was made which was crystallized in a °C oil bath.

This spout part crystallized preform is processed using a biaxial stretching blow molding machine (
LBO manufactured by CORPO-PL^ST
1), the film was biaxially stretched by about 2 times in the length and about 3 times in the width under conditions of a blowing pressure of 201qr10a, a preform heating time of about 60 seconds, and a stretching temperature of 100°C.
After holding it in a mold that requires a surface temperature of 0°C for about 10 seconds, heat setting is performed by cooling the mold,
A biaxially stretched bottle with an internal volume of 1.01 cm, a body with six vacuum panels, and a raised bottom was produced. The transparency of the bottle was good.

Next, this bottle was filled with hot water at 85°C, left at room temperature for 10 minutes, and then cooled by immersion in water at about 25°C. When the shape of the bottle was examined, no deformation was observed.

In producing a biaxially stretched bottle using the polyethylene terephthalate obtained by solid phase polymerization in Examples 2.3 and 4, the conditions for biaxially stretched blow molding were as shown in Table 2. It was molded in the same manner as in Example 5 except for the following. The transparency of the bottle was good. Furthermore, the obtained biaxially stretched bottles were each placed at an angle of 85° in the same manner as in Example 5.
As a result of a deformation test of the bottles filled with hot water of C, no deformation was observed in any of the bottles.

Comparative Examples 2 to 3 Comparative Examples 1'3'll Using polyethylene terephthalate obtained by in-phase polymerization of 1, Example 5.
Biaxially stretched bottles were manufactured under exactly the same conditions as in Nos. 6 and 7. The body of the bottle was slightly whitened.

Further, each of the obtained biaxially stretched bottles was filled with 85 hot water in the same manner as in Example 5, and a bottle deformation test was conducted.

As a result, both bottles experienced shrinkage at the bottle shoulder.
In addition, blistering was observed on the panel of the bottle body.

Old-λ Eco! Since the polyethylene terephthalate of the present invention has excellent strength, heat resistance, and transparency, blow-molded containers made from the polyethylene terephthalate of the present invention can be used for juices, soft drinks, carbonated drinks, seasonings, etc. It has excellent high-temperature filling properties, such as, no thermal deformation during high-temperature filling, can be easily sterilized, and has excellent high-speed filling properties.

[Brief explanation of the drawing]

FIG. 1 shows an example of a process diagram of an apparatus for explaining the method for producing polyethylene terephthalate of the present invention. 15.16... Polyester extraction device 17-20.
... Rectification column 21-28 ... Cooler 29-30 ...
・Register part...Slurry preparation tank 2...Slurry storage tank 3.
4... Esterification reaction device 5.6... Esterification reaction and polycondensation combined use device 7...
Polycondensation device 8...Horizontal continuous polycondensation device

Claims (1)

[Claims] (1) (A) General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼...The ethylene terephthalate component unit (a) represented by [I] is 97.0 to 98 The dioxyethylene terephthalate component unit (b) represented by the range of .6 mol% and the general formula [II] ▲Mathematical formula, chemical formula, table, etc.▼...[II] is 1.4 to 3.0 mol formed from a range of %,
and both component units are arranged randomly, (B) the intrinsic viscosity [η] measured at 25°C in o-chlorophenol is in the range of 0.70 to 0.90 dl/g, (C) The crystallization temperature (Tcc) measured with a differential scanning calorimeter (DSC) at a heating rate of 10°C/min is 165.0°C or higher, and 67.5[η]+119.0≦Tcc≦67. 5[η]+133.5 Polyethylene terephthalate characterized by: (2) (A) General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... Ethylene terephthalate component unit (a) represented by [I] is in the range of 97.0 to 98.6 mol% and general formula [II] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... [II] The dioxyethylene terephthalate component unit (b) represented by the formula [II] is formed in a range of 1.4 to 3.0 mol%. ,
and both component units are arranged randomly, (B) the intrinsic viscosity [η] measured at 25°C in o-chlorophenol is in the range of 0.70 to 0.90 dl/g, (C) The crystallization temperature (Tcc) measured with a differential scanning calorimeter (DSC) at a heating rate of 10°C/min is 165.0°C or higher, and 67.5[η]+119.0≦Tcc≦67. 5[η]+133.5 A preform for a hollow molded body formed from polyethylene terephthalate characterized by: (3) (A) General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... Ethylene terephthalate component unit (a) represented by [I] is in the range of 97.0 to 98.6 mol% and general formula [II] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... [II] The dioxyethylene terephthalate component unit (b) represented by the formula [II] is formed in a range of 1.4 to 3.0 mol%. ,
and both component units are arranged randomly, (B) the intrinsic viscosity [η] measured at 25°C in o-chlorophenol is in the range of 0.70 to 0.90 dl/g, (C) The crystallization temperature (Tcc) measured with a differential scanning calorimeter (DSC) at a heating rate of 10°C/min is 165.0°C or higher, and 67.5[η]+119.0≦Tcc≦67. 5[η]+133.5 A blow-molded container made of polyethylene terephthalate characterized by: (4) (A) General formula [
I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... [I] The ethylene terephthalate component unit (a) represented by is in the range of 97.0 to 98.6 mol% and the general formula [II] ▲Math, There are chemical formulas, tables, etc. ▼... [II] The dioxyethylene terephthalate component unit (b) represented by is formed in a range of 1.4 to 3.0 mol%,
and both component units are arranged randomly, (B) the intrinsic viscosity [η] measured at 25°C in o-chlorophenol is in the range of 0.70 to 0.90 dl/g, (C) The crystallization temperature (Tcc) measured with a differential scanning calorimeter (DSC) at a heating rate of 10°C/min is 165.0°C or higher, and 67.5[η]+119.0≦Tcc≦67. 5 [η] + 133.5, and (D) the number of spherulites produced when melted at 290°C and then isothermally crystallized at 200°C (a) is 10^8 pieces/m^ 3 or less, and the difference between the number of spherulites (a) and the number of spherulites produced when isothermally crystallized at 200 °C after melting at 280 °C ((b) - (a) ) is 5×10^7 pieces/m^3 or less. (5) (A) General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... Ethylene terephthalate component unit (a) represented by [I] is in the range of 97.0 to 98.6 mol% and general formula [II] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... [II] The dioxyethylene terephthalate component unit (b) represented by the formula [II] is formed in a range of 1.4 to 3.0 mol%. ,
and both component units are arranged randomly, (B) the intrinsic viscosity [η] measured in o-chlorophenol at 25°C is in the range of 0.70-0.90 dl/g, (C) The crystallization temperature (Tcc) measured with a differential scanning calorimeter (DSC) at a heating rate of 10°C/min is 165.0°C or higher, and 67.5[η]+119.0≦Tcc≦67. 5 [η] + 133.5, and (D) the number of spherulites produced when melted at 290°C and then isothermally crystallized at 200°C (a) is 10^8 pieces/m^ 3 or less, and the difference between the number of spherulites (a) and the number of spherulites produced when isothermally crystallized at 200 °C after melting at 280 °C ((b) - (a) ) is 5×10^7 pieces/m^3 or less, a preform for a hollow molded body formed from polyethylene terephthalate. (6) (A) General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... Ethylene terephthalate component unit (a) represented by [I] is in the range of 97.0 to 98.6 mol% and general formula [II] ▲There are mathematical formulas, chemical formulas, tables, etc.▼... [II] The dioxyethylene terephthalate component unit (b) represented by the formula [II] is formed in a range of 1.4 to 3.0 mol%. ,
and both component units are arranged randomly, (B) the intrinsic viscosity [η] measured at 25°C in o-chlorophenol is in the range of 0.70 to 0.90 dl/g, (C) The crystallization temperature (Tcc) measured with a differential scanning calorimeter (DSC) at a heating rate of 10°C/min is 165.0°C or higher, and 67.5[η]+119.0≦Tcc≦67. 5 [η] + 133.5, and (D) the number of spherulites produced when melted at 290°C and then isothermally crystallized at 200°C (a) is 10^8 pieces/m^ 3 or less, and the difference between the number of spherulites (a) and the number of spherulites produced when isothermally crystallized at 200 °C after melting at 280 °C ((b) - (a) ) is less than or equal to 5 x 10^7 pieces/m^3.