JPH05186571A - Copolyester, and hollow container and stretched film prepared therefrom - Google Patents

Abstract

PURPOSE:To prepare a polymer which is specified in intrinsic viscosity, Sb content, concn. and proportion of terminal carboxyl group, and cyclic trimer content, contains little oligomer, and is excellent in productivity, heat resistance, and mechanical properties by copolymerizing terephthalic acid with a specific diol component. CONSTITUTION:A dicarboxylic acid component consisting of terephthalic acid is copolymerized with a diol component consisting mainly of ethylene glycol and contg. 0.5-3.5mol% cyclohexanedimethanol and 1.0-2.5mol% diethylene glycol to give a copolyester having an intrinsic viscosity of 0.60-1.50dl/g, an Sb content of 150-300wt.ppm. a concn. of terminal carboxyl group of 18eq./ton or lower, a proportion of the terminal carboxyl group to the total carboxyl group of 8-20 equivalent %, and a cyclic trimer content of 0. 35wt.% or lower.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a copolyester useful for bottles, films, sheets and the like. More specifically, the present invention relates to a copolymerized polyester having a low content of oligomers that cause contamination of molds and the like during molding and excellent in productivity, heat resistance, mechanical strength and the like, and a molded product thereof.

[0002]

2. Description of the Related Art Polyethylene terephthalate (hereinafter referred to as
It is called "PET". ) Has excellent mechanical strength, chemical stability, transparency, hygiene, etc., and since it is lightweight and inexpensive, it is widely used as packaging materials for various sheets and containers, especially carbonated drinks and fruit juice drinks. , Containers for liquid seasonings, edible oil, liquor, wine, etc. In the case of such a PET, for example, in the case of a bottle, a preform for a hollow molded body is molded by an injection molding machine, and this preform is stretch-blown in a mold having a predetermined shape. Also, in the case of content liquids that require heat filling, such as fruit juice drinks,
In the blow mold or in a mold separately provided,
It is generally heat-set and molded into a bottle.

However, in the conventional PET chips used for molding, the amount of cyclic trimer having an oligomer as a main component is usually 1 to 2% by weight in a melt-polymerized chip, and usually 0.5 in a solid-phase polymerized chip. ~ 1.0 wt%, these oligomers adhere to equipment such as molds during molding,
To contaminate. Contamination of the mold or the like causes the surface of the molded product to become rough or white. Therefore, it is necessary to clean the mold and the like as often as possible. Therefore, in the past, attempts have been made to extend the solid phase polymerization time or increase the amount of catalyst to lower oligomers, but there is a limit to the reduction of oligomers by such a method, and it is not economical. Absent. On the other hand, there are many known copolyesters having properties similar to PET, for example, copolyesters using terephthalic acid and isophthalic acid as dicarboxylic acid components and copolyesters using ethylene glycol and diethylene glycol as glycol components. Has been. However, a copolymerized polyester in which the amount of oligomer is reduced to a certain extent or more and which has physical properties equal to or higher than that of PET has not been specifically known.

[0004]

DISCLOSURE OF THE INVENTION The object of the present invention is to prevent contamination of molds and the like at the time of molding, to have a low oligomer content, and to have less by-product of oligomer at the time of molding, and to be equal to or higher than that of conventional PET. Another object of the present invention is to provide a highly productive copolyester having high heat resistance.

[0005]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the inventors of the present invention have found that the conventional PET has a specific physical property range in which a small amount of cyclohexanedimethanol units and diethylene glycol units are contained. The inventors have found a polymerized polyester and reached the present invention. That is, the gist of the present invention is a copolyester having terephthalic acid as a dicarboxylic acid component and ethylene glycol as a diol component as a main component, and cyclohexanedimethanol is 0.5 to 3.5 as a diol component. Mol%, diethylene glycol 1.0-2.5 mol%,
(2) Intrinsic viscosity of 0.60 to 1.50 dl / g, (3)
The content of antimony atoms is 150 to 300 ppm by weight,
(4) The concentration of terminal carboxyl groups is 18 eq / ton or less, and (5) the ratio of the terminal carboxyl groups in the total terminal groups is 8
˜20 equivalent%, (6) the content of cyclic trimer is 0.35 wt% or less,

[0006] The present invention relates to a copolyester characterized by: The method for producing the copolymerized polyester is a copolymerized polyester containing terephthalic acid as a dicarboxylic acid component and ethylene glycol as a diol component,
(1) As a diol component, cyclohexanedimethanol is 0.5 to 3.5 mol%, diethylene glycol is 1.0 to 2.5 mol%, and (2) the intrinsic viscosity is 0.50 to
0.70 dl / g, (3) Antimony atom content is 1
50-300 ppm by weight, (4) the concentration of terminal carboxyl groups is 15 to 30 eq / ton or less, (5) the proportion of terminal carboxyl groups in the total terminal groups is 12 to 22 equivalent%, and is a copolyester (hereinafter referred to as " A solid-state polymerization of a "prepolymer") is preferable.

The present invention will be described in detail below. As for the terephthalic acid and ethylene glycol as the main components of the copolyester of the present invention, known raw materials used in PET may be used. The cyclohexanedimethanol raw materials of the present invention include 1,2-1,3, and 1,4
-Cyclohexanedimethanol, its cis,
The trans isomer ratio may be a mixture in any ratio. Of these, usually 1,4-cyclohexanedimethanol,
A cis / trans ratio of (10 to 50) / (90 to 50) is particularly preferably used.

Diethylene glycol (hereinafter referred to as "DE
G)) is partially produced as a by-product from ethylene glycol during the polymerization reaction. Therefore, in addition to the case where a predetermined amount of diethylene glycol or its ester-forming derivative is used as a polymerization raw material, reaction conditions, additives, etc. The content of DEG can be controlled only by appropriately selecting. In particular, in the case of the copolyester of the present invention, the melt polymerization temperature can be lowered by the effect of adding cyclohexanedimethanol, and the DEG amount can be easily kept low. Examples of the additive include tertiary amines such as triethylamine, tri-n-butylamine and benzyldimethylamine, and quaternary hydroxides such as tetraethylammonium hydroxide, tetrabutylammonium hydroxide and trimethylbenzylammonium hydroxide. Generation of DEG can be suppressed by adding a small amount of basic compounds such as ammonium and lithium carbonate, sodium carbonate, potassium carbonate and sodium acetate. On the other hand, if a small amount of an inorganic acid such as sulfuric acid or an organic acid such as benzoic acid is added to the polymerization raw material, the generation of DEG is promoted,
The content can also be increased.

Additives for controlling the amount of DEG produced are usually added to the total amount of the polymerization raw materials in an amount of 0.00
1 to 10% by weight, preferably 0.005 to 1% by weight is used. In the copolyester of the present invention, cyclohexanedimethanol in all dicarboxylic acid components is 0.5 to 3.
0 mol%, preferably 1.0 to 2.5 mol%,
In addition, the proportion of DEG in all diol components is 1.0 to 2.
It is 5 mol%, preferably 1.2 to 2.3 mol%.
If the amount is less than the above range, the effect of reducing oligomers attached to the mold at the time of molding is small, and superiority over conventional PET cannot be recognized. On the other hand, if it exceeds the range, the heat resistance is lowered, which is not preferable. Next, the intrinsic viscosity of the copolyester of the present invention is 0.60 to 1.50 dl / g, preferably 0. 0, measured at 30 ° C in a mixed solvent of phenol / tetrachloroethane (weight ratio 1/1). 70-
It is 1.00 dl / g. Below 0.60 dl / g,
When the obtained copolyester is used as a molded product, it cannot have a sufficient strength and elongation. On the other hand, when it exceeds 1.50 dl / g, the melt viscosity becomes too high, and the shear heat generation in the valve during injection and extrusion molding becomes large, so that a large amount of once reduced oligomer is by-produced again. As a result, the improvement of contamination of the mold is not recognized, which is not preferable.

The content of antimony atom in the copolyester of the present invention is 150 to 300 ppm by weight, preferably 200 to 250 ppm by weight. When the content of the antimony atom is less than the above range, it is not practical because the reduction of the oligomer is slow and the solid phase polymerization rate is slow in the production. Further, when exceeding the range,
It is not preferable because the amount of oligomer by-product at the time of molding is increased and the stain on the mold is not sufficiently improved. This antimony atom is derived from an antimony compound used as a polymerization catalyst for the copolyester in the present invention described later,
It is incorporated in the polymer.

Further, the concentration of unterminated carboxyl groups of the copolyester of the present invention is 18 eq / ton or less, preferably 15 eq / ton or less. When the concentration of the terminal carboxyl group exceeds the above range, the effect of reducing the oligomers attached to the mold or the like during molding is small, and the moisture resistance and heat stability are also reduced, which is not preferable. In the copolymerized polyester of the present invention, the proportion of terminal carboxyl groups in the total terminal groups is 8 to 20 equivalent%, preferably 10 to 18%.
Equivalent%. If the amount is less than the above range, the solid phase polymerization rate in the production is slow, and it takes a long time to reach the target intrinsic viscosity, resulting in poor productivity, and the amount of oligomer by-product during molding tends to increase. Is not preferable. On the other hand, when the amount exceeds the above range, it is not preferable because the oligomer is slowly reduced in the production, and the moisture resistance and the thermal stability are lowered.

All the above conditions are satisfied, and the content of the cyclic trimer which is the main component of the oligomer is 0.35% by weight.
By providing the copolymerized polyester in an amount of preferably 0.32% by weight or less, and more preferably 0.30% by weight or less, it is possible to improve the contamination of the mold and the like. Even when the content of the cyclic trimer exceeds 0.35% by weight, for example, when it is about 0.40% by weight, some improvement in pollution can be seen, but it cannot be said to be sufficient. Contamination such as mold is noticeable. The above-described copolyester of the present invention is produced by performing melt polymerization and subsequent solid-phase polymerization according to a conventionally known method for PET. Hereinafter, the manufacturing method will be described in detail.

The melt polymerization method is, for example, a method in which terephthalic acid, ethylene glycol and cyclohexanedimethanol are used to carry out a direct esterification reaction under pressure, and then the temperature is further raised and the pressure is gradually reduced to carry out a polycondensation reaction. is there. Alternatively, an ester derivative of terephthalic acid, for example, dimethyl terephthalic acid, is subjected to an exchange reaction using a transesterification reaction using ethylene glycol and cyclohexanedimethanol, and then,
It can be produced by further polycondensing the obtained reaction product. In these polycondensation reactions, cyclohexanedimethanol can be added at any stage of the esterification reaction, transesterification reaction, or initial stage of the polycondensation reaction, but is preferably the initial stage of the esterification reaction or transesterification reaction. ..

Such polycondensation reaction may be carried out in one step or in plural steps. When carrying out in multiple stages, the polycondensation reaction conditions are such that the reaction temperature of the first stage polycondensation is usually 250 to 290 ° C, preferably 260 to 280 ° C.
And the pressure is usually 500-20 torr, preferably 2
The temperature of the final polycondensation reaction is usually 265 to 300 ° C., preferably 270 to 29.
The temperature is 5 ° C. and the pressure is usually 100 to 0.1 Torr, preferably 5 to 0.5 Torr. When the polycondensation reaction is carried out in two stages, the polycondensation reaction conditions in the first stage and the second stage are within the above ranges, respectively, and when carried out in three or more stages, from the second stage The reaction conditions of the polycondensation reaction up to the first stage before the final stage are those between the reaction conditions of the first stage and the reaction conditions of the final stage.

For example, when the polycondensation reaction is carried out in three stages, the reaction temperature for the second stage polycondensation reaction is usually 2
60 to 295 ° C, preferably 270 to 285 ° C,
The pressure is usually in the range of 50-2 Torr, preferably 40-5 Torr. The intrinsic viscosity reached in each of these polycondensation reaction steps is not particularly limited, but it is preferable that the degree of increase in the intrinsic viscosity in each stage is smoothly distributed, and further from the final stage polycondensation reactor. The intrinsic viscosity of the obtained prepolymer is usually 0.45 to 0.80 dl /
g, preferably 0.5 to 0.70 dl / g. Below this range, chipping becomes difficult, and above this range, it is difficult to extract the prepolymer from the reaction vessel, and the effect of reducing oligomers when subjected to solid phase polymerization is reduced. The obtained prepolymer is usually formed into granular chips by melt extrusion. It is desirable that such granular chips generally have an average particle size of 2.0 to 5 mm, preferably 2.2 to 4.0 mm. In the above esterification reaction, transesterification reaction and polycondensation reaction, it is preferable to use an esterification catalyst, a transesterification catalyst, a polycondensation catalyst, a stabilizer and the like.

As the transesterification catalyst, one or more known compounds such as calcium, titanium, manganese, zinc, sodium and lithium compounds can be used, but a manganese compound is particularly preferable from the viewpoint of transparency. An antimony compound is used as the polymerization catalyst. As antimony compound, antimony oxide,
Examples thereof include inorganic acid salts, organic acid salts, halides and sulfides, but other metal catalysts, for example, compounds such as germanium, titanium and cobalt can also be used in combination. The amount of the catalyst, as both the esterification catalyst and the polymerization catalyst, is usually 5 to 2000 ppm by weight in the total polymerization raw material as a metal.
It is preferably used in the range of 10 to 500 ppm by weight, and the amount of the antimony compound is particularly preferably such that the content of the antimony atom in the copolyester of the present invention and the copolyester in the production thereof is preferably 150 to 3
00 ppm by weight, more preferably 200 to 250 ppm by weight
It is desirable to use a suitable amount such that it is in the pm range. In order to satisfy the range, for example, when antimony trioxide is used, it is usually 180 to 10 with respect to the polymer.
Although about 100 ppm by weight of antimony trioxide is used during melt polymerization, it can be controlled separately by the temperature, pressure, polymerization time during polymerization and the ratio of dicarboxylic acid component to glycol component of the esterification reaction product. it can.

Examples of the stabilizers include phosphoric acid esters such as trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, trioctyl phosphate, triphenyl phosphate, tricresyl phosphate, triphenyl phosphite and trisdodecyl phosphate. Phosphite such as phyto, trisnonyl phenyl phosphite, methyl acid phosphate, isopropyl acid phosphate, butyl acid phosphate, dibutyl phosphate, monobutyl phosphate, acid phosphate such as dioctyl phosphate and phosphoric acid, phosphite, Phosphorus compounds such as polyphosphoric acid are preferred. The stabilizer is usually 10 to 1000 pp, based on the weight of phosphorus atoms in the stabilizer, in all polymerization raw materials.
m, preferably in the range of 20 to 200 ppm. The weight ratio of the phosphorus atom contained in the prepolymer or the copolyester after solid state polymerization to the antimony atom is usually 0.05 to 0.5 times, preferably 0.1 to 0.4 times. It is desirable to use it in the range of. Within this range, the effect of reducing oligomers and the heat stabilizer are good. It is desirable to use it in a range of preferably 0.1 to 0.1 times.

Further, a dicarboxylic acid component other than terephthalic acid and a diol component other than ethylene glycol, cyclohexanedimethanol, and diethylene glycol may be contained in a small amount as long as they do not deviate from the above-mentioned constitutional requirements of the present invention. Examples of these dicarboxylic acid components include phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenylsulfone dicarboxylic acid, 4,4′-biphenyldicarboxylic acid and structural isomers thereof, aliphatic acids such as malonic acid, succinic acid, and adipic acid. Examples of the carboxylic acid, the oxy acid or the derivative thereof include p-hydroxybenzoic acid, p-hydroxybenzoic acid ester and glycolic acid. Further, as the diol component, 1,
2-propanediol, 1,3-propanediol,
1,4-butanediol, pentamethylene glycol,
Hexamethylene glycol, neopentyl glycol,
Examples thereof include aliphatic glycols such as diethylene glycol, alicyclic glycols such as cyclohexanediethanol, and aromatic dihydroxy compound derivatives such as bisphenol A and bisphenol S. An amount that is substantially equivalent to the total diol component and the total dicarboxylic acid component is used.

As described above, the composition (constitutional unit) of the prepolymer produced by melt polymerization is substantially the same as that of the copolyester of the present invention obtained by subjecting the prepolymer to solid phase polymerization. The concentration of the terminal carboxyl group in the prepolymer is usually 15 to 30 eq / t.
On, preferably 18 to 25 eq / ton. If it is less than the above range, the solid phase polymerizability is poor and it takes a long time to increase the intrinsic viscosity, which is not preferable. If it exceeds the range, the effect of reducing oligomers when subjected to solid phase polymerization is small. Furthermore, the ratio of the terminal carboxyl groups in the total end groups of the prepolymer is 12 to
It is in the range of 22 equivalent%, preferably 14 to 20 equivalent%. If it is less than this range, the solid-phase polymerizability is poor, and it takes a long time to increase the intrinsic viscosity to a practical level, which is not preferable. If it exceeds the range, it is not preferable because the effect of reducing the oligomer during solid-state polymerization is small.

Next, in order to obtain the copolyester of the present invention, it is necessary to further subject the prepolymer chips obtained by the melt polymerization as described above to solid phase polymerization treatment. The prepolymer chips supplied to the solid phase polymerization may be heated to a temperature lower than the temperature at which the solid phase polycondensation is performed in advance to perform pre-crystallization, and then supplied to the solid phase polycondensation step. In such a pre-crystallization step, the copolyester chips are usually dried at 120 to 200 ° C, preferably 13
It can also be carried out by heating at a temperature of 0 to 180 ° C. for 1 minute to 4 hours, or at a temperature of 120 to 200 ° C. for 1 minute or more, usually by heating the chip under an atmosphere of steam or an inert gas containing steam. You can also

The solid-state polymerization step in which the above-mentioned prepolymer chips are supplied comprises at least one stage, and the polymerization temperature is usually 190 to 230 ° C, preferably 195 ° C to 22 ° C.
It is carried out under an inert gas atmosphere of nitrogen, argon, carbon dioxide or the like under the conditions of 5 ° C. and a pressure of usually 1 kg / cm ² G to 10 Torr, preferably normal pressure to 100 Torr. With respect to the polymerization time, the higher the temperature, the shorter the time it takes to reach the desired physical properties, but usually 1 to 50 hours, preferably 5
-30 hours, more preferably 10-25 hours. By appropriately selecting the conditions of the above solid-phase polymerization treatment,
The copolyester of the present invention can be obtained. The polyester of the present invention thus obtained can be used to form films, sheets, containers, and other packaging materials using the melt molding method generally used in PET.
Further, it is possible to improve the mechanical strength by stretching the copolyester at least uniaxially.

The stretched film made of the polyester of the present invention is obtained by uniaxially stretching, sequential biaxially stretching or simultaneous biaxially stretching a sheet obtained by injection molding or extrusion molding. It is molded using any stretching method. It is also possible to form a cup or tray by pressure forming or vacuum forming. In producing such a stretched film, the stretching temperature may be set between the glass transfer temperature of the copolyester of the present invention and a temperature 70 ° C. higher than that, and usually 40 to 170 ° C., preferably 60 to 140 ° C. is there. The stretching may be uniaxial or biaxial, but biaxial stretching is preferable from the viewpoint of practical physical properties of the film. In the case of uniaxial stretching, the stretching ratio is usually 1.
1 to 10 times, preferably 1.5 to 8 times, and in the case of biaxial stretching, it is usually 1.1 to 8 times, preferably 1.5 to 5 times in each of the machine direction and the transverse direction. You can go within the range. Also, the vertical magnification / horizontal magnification is usually 0.5-
2.0, preferably 0.7 to 1.3. The obtained stretched film can be further heat-fixed to improve heat resistance and mechanical strength. Heat fixation is usually 120 ° C to melting point, preferably 150 to 230 ° C under tension such as compressed air.
It is usually several seconds to several hours, preferably several tens of seconds to several minutes.

In producing a hollow molded article, a preform formed from the copolyester of the present invention is stretch blow-molded, and an apparatus conventionally used for PET blow molding can be used. Specifically, for example, a preform is once molded by injection molding or extrusion molding, and then it is reheated as it is or after processing the plug portion and the bottom portion, and biaxial stretching such as hot parison method or cold parison method. Blow molding method is applied.
In this case, the molding temperature, specifically, the temperature of each part of the cylinder and nozzle of the molding machine can be set in the range of 260 to 280 ° C., which is lower than that of general PET by 1 to 10 ° C.
It is easy to keep the amount of oligomer low. Further, it is possible to suppress the decrease in the intrinsic viscosity to be low, and it is also easy to suppress the amount of acetaldehyde produced as a by-product to be low. The stretching temperature is usually 70 to 120 ° C, preferably 80 to 110 ° C.
The stretching ratio is usually 1.5 to 3.5 times in the longitudinal direction and 2 to 5 times in the circumferential direction. The obtained hollow molded article can be used as it is, but in the case of a content liquid such as fruit juice drink and oolong tea which requires heat filling, it is generally further heat-fixed in a blow mold and further heat-resistant. It is used by imparting sex. The heat setting is usually 100 to 200 ° C., preferably 120 to 1 under tension such as compressed air.
It is carried out at 80 ° C. for several seconds to several hours, preferably several seconds to several minutes.

[0024]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. Various measuring methods used in this example are shown below. The measurement of the intrinsic viscosity is as described above. (1) Amount of cyclohexanedimethanol (hereinafter referred to as "CHDM
Quantity. ) After decomposing by methanol by a conventional method, the produced monomer component was quantified by gas chromatography. (2) Diethylene glycol amount (hereinafter referred to as "DEG amount") Hydrolyzed by a conventional method, and the produced diol component was quantified by gas chromatography. (3) Cyclic trimer amount (hereinafter referred to as "CT amount") 200 mg of a copolymerized polyester sample was added to chloroform /
It was dissolved in 2 ml of a mixed solution of hexafluoroisopropanol (volume ratio 3/2) and further diluted with 20 ml of chloroform. To this, 10 ml of methanol was added to reprecipitate a sample, and a filtrate after filtration was obtained. After drying the filtrate to dryness,
A liquid obtained by dissolving the residue in 25 ml of dimethylformamide was analyzed and quantified by liquid chromatography.

(4) Terminal carboxyl group concentration (hereinafter referred to as "A
V ”. ) 100 mg of the copolymerized polyester sample was dissolved in 5 ml of benzyl alcohol by heating, and 5 ml of chloroform was added to the solution to dilute it.
It was titrated with an N-sodium hydroxide / benzyl alcohol solution and quantified. (5) Total terminal group concentration (hereinafter referred to as "TEV") Calculated from the intrinsic viscosity using the following formula. TEV = {2000000 / (1359 x intrinsic viscosity)
1.460} (unit: eq / ton) (6) Antimony atom content (hereinafter referred to as "Sb amount") 2.0 g of a copolyester sample was ashed by a conventional method in the presence of sulfuric acid, completely decomposed, and then distilled. The volume of 100 ml of water was quantified by emission spectroscopy. (7) Phosphorus atom content (hereinafter referred to as "P amount") It was quantified by an emission spectroscopic analysis method in the same manner as the analysis of the antimony atom content. (8) Inert gas flow rate The inert gas flow rate is the amount of gas flowing per unit time (hr) and per unit resin weight (kg) at 1 atm and 25 ° C.
The volume amount (L) converted to

[0026]

Example 1 13.0 kg of terephthalic acid, 1,4-cyclohexanedimethanol (cis / trans = 30/7)
0) 0.27 kg and ethylene glycol 5.82 k
g slurry was prepared and 0.30 kg of bis (β-
Hydroxyethyl) terephthalate was added, 250 ° C
It was sequentially supplied to the esterification tank held at 4 hours over 4 hours.
After the completion of the feeding, the esterification reaction was allowed to proceed for 1 hour, and then half of the amount was transferred to a polycondensation tank to obtain phosphoric acid (1.92 g) (based on the polymer 2).
50 ppm) and 2.77 g of antimony trioxide (versus 360 ppm of polymer) were charged at 250 ° C. to 280 ° C.
The temperature is gradually raised to 0.degree.
It was kept at 5 mmHg. After the reaction was performed for 2.5 hours, prepolymer chips were obtained by melt extrusion. The physical properties of the prepolymer are shown in Table 1. Next, the surface of the prepolymer chip was crystallized at 150 ° C. with a stirring crystallization machine (manufactured by Bepex), and then transferred to a stationary solid phase polymerization tower,
Under a nitrogen flow of 20 l / kg-hr, it was dried at about 150 ° C for 3 hours and then solid-phase polymerized at 208 ° C for 20 hours to obtain a solid-phase polymerized chip. The physical properties of the chip are shown in Table-2.

Next, using the solid-state polymerization chip, an injection molding machine manufactured by Toshiba Corp. was used, in which each cylinder and nozzle temperature was 275 ° C., screw rotation speed was 100 rpm, injection time was 10 seconds, and mold cooling water temperature was 10 ° C. A preform was molded with IS-60B. After the mouthpiece of this preform was heated and crystallized by a self-made crystallization machine, it was blow-molded by a stretch blow molding machine set at a preheating furnace temperature of 90 ° C., a blow pressure of 20 kg / cm ³ , and a molding cycle of 10 seconds. Part average wall thickness 30
A bottle having a size of 11 μm and an internal volume of 11 was prepared, and subsequently heat-set for 10 seconds in a mold set at 150 ° C. under compressed air tension. The physical properties of the bottle are shown in Table-2. Although 1000 bottles were continuously molded, no contamination was observed in any of the injection molding, stretch-blowing, and heat-setting dies. Furthermore, 90 ℃
The above-mentioned bottle was filled with the orange juice liquid that had been sterilized at 85 ° C and allowed to cool to 85 ° C, and the bottle was capped and inverted for 15 minutes, but no liquid leakage or deformation of the mouth plug, shoulder, or body was observed. It was

[0028]

Example 2 The pute polymer chip obtained in Example 1 was subjected to solid phase polymerization at 215 ° C. for 20 hours in the same manner as in Example 1 to obtain a solid phase polymerized chip. Table 2 shows the physical properties of the solid-state polymerization chip. Next, the solid-state polymerized chip was obtained in the same manner as in Example 1 except that the temperature of each part of the cylinder of the injection molding machine and the temperature of the nozzle were 265 ° C. to obtain a heat-fixed bottle having a capacity of 1 l. The physical properties of the bottle are shown in Table-2. Further, the bottle was completely good in appearance without whitening. Further, no contamination of the mold was observed even when the continuous operation was performed as in Example 1.
Furthermore, no change was observed in the bottle in the heat filling test carried out in the same manner as in Example 1.

[0029]

Example 3 Polymerization was carried out in the same manner as in Example 1 except that 1.07 g of orthophosphoric acid and 2.39 g of antimony trioxide were used. Table 1 shows the physical properties of the obtained prepolymer chips.
Shown in. Then, a solid-state polymerization chip and a heat-fixing bottle having a capacity of 1 l were obtained from the prepolymer chip in the same manner as in Example 1. The physical properties of the chip and bottle are shown in Table-2. Further, no contamination of the mold was observed even when the continuous operation was performed as in Example 1. Furthermore, no change was observed in the bottle in the heat filling test carried out in the same manner as in Example 1.

[0030]

Example 4 Polymerization was carried out in the same manner as in Example 1 except that 0.683 g of orthophosphoric acid and 2.63 g of antimony trioxide were used and the polycondensation time was 3 hours. The physical properties of the obtained prepolymer chip are shown in Table 1. Then, a solid-state polymerization chip and a heat-fixing bottle having a capacity of 1 l were obtained from the prepolymer chip in the same manner as in Example 1. The physical properties of the chip and bottle are shown in Table-2. Further, no contamination of the mold was observed even when the continuous operation was performed as in Example 1. Furthermore, Example 1
No change was observed in the bottle in the heat-filling test carried out in the same manner as in.

[0031]

Example 5 The same as Example 1 except that 0.135 kg of 1,4-cyclohexanedimethanol (cis / trans = 20/80), 1.29 g of orthophosphoric acid and 2.60 g of antimony trioxide were used. Then, polymerization was carried out. The physical properties of the obtained prepolymer chip are shown in Table 1. From the prepolymer chip, a solid-state polymerization chip and a 1 l capacity heat-fixing bottle were obtained in the same manner as in Example 1. The physical properties of the chip and bottle are shown in Table-2. Further, no contamination of the mold was observed even when the continuous operation was performed as in Example 1. Furthermore, no change was observed in the bottle in the heat filling test carried out in the same manner as in Example 1.

[0032]

Example 6 Dimethyl terephthalate 14.8 kg, 1,
4-cyclohexanedimethanol (cis / trans = 4
0/60) 0.265 kg, ethylene glycol 9.6
0 kg and 2.60 g of manganese acetate tetrahydrate were charged into a reaction can, and the produced methanol was distilled off while gradually raising the temperature from 160 ° C. to 220 ° C. over 4 hours to carry out a transesterification reaction. 1.80 orthophosphoric acid was added to this reaction product.
g, cobalt acetate tetrahydrate 1.26 g, antimony trioxide 4.30 g, and finally 275 ° C., 0.5 mmH
Prepolymer chips were obtained at a polymerization time of 3 hours under a temperature of g. The physical properties of this prepolymer chip are shown in Table 1. From the prepolymer chip, a solid-state polymerization chip and a 1 l capacity heat-fixing bottle were obtained in the same manner as in Example 1. The physical properties of the chip and bottle are shown in Table-2. Further, no contamination of the mold was observed even when the continuous operation was performed as in Example 1. Furthermore, no change was observed in the bottle in the heat filling test carried out in the same manner as in Example 1. On the other hand, using the solid-state polymerization chip, a sheet having a wall thickness of 300 μm was molded with a 30 mmφ extruder in which the temperature of each part of the cylinder and the nozzle was 275 ° C., the screw rotation speed was 40 rpm, and the extrusion rate was 80 g / min. The extrusion molding was continuously continued for 10 hours, but the cooling drum was not contaminated. Furthermore, a long stretching machine (TM Long
Co., Ltd.) and simultaneously biaxially stretched 3 × 3 times, and then heat-set in an oven at 200 ° C. for 120 seconds under tension to 100 μm.
A thick stretched film was obtained. The film had an intrinsic viscosity of 0.73 dl / g and a CT amount of 0.39% by weight.

[0033]

Comparative Example 1 A prepolymer was obtained in the same manner as in Example 1 except that cyclohexanedimethanol was not added. The physical properties of the preporemer are shown in Table 1. Then, in the same manner as in Example 1, solid phase polymerization was carried out at 208 ° C. for 20 hours to obtain a solid phase polymerization chip. Table 3 shows the physical properties of the chip.
Table 3 shows the physical properties of a 1 l capacity heat-fixing bottle obtained from this chip in the same manner as in Example 1. In addition, the same hot-filling test results as in Example 1 were good for this bottle, but when a mold after molding was observed as a continuous molding test, a thin white film-like deposit was observed.

[0034]

Comparative Example 2 The prepolymer obtained in Comparative Example 1 was subjected to solid phase polymerization at 208 ° C. for 30 hours in the same manner as in Example 1 to obtain a solid phase polymerization chip. Table 3 shows the physical properties of the solid-state polymerization chip.
Shown in. The solid-state polymerization chip was obtained in the same manner as in Example 1
Table 3 shows the physical properties of the heat-fixing bottle having a volume of 1 l. Further, although the same result of the heat filling test as in Example 1 was good for the bottle, a thin white film-like deposit was observed when the mold after the molding was observed as a continuous molding test. Further, a preform of the solid-state polymerized chip was molded in the same manner as in Example 1 except that the temperature of each cylinder of the injection molding machine and the nozzle temperature were 270 ° C. However, the obtained preform was white and opaque and could not be molded normally.

[0035]

Comparative Example 3 Polymerization was carried out in the same manner as in Example 1 except that 0.80 kg of 1,4-cyclohexanedimethanol (cis / trans = 30/70) was used. Table 1 shows the physical properties of the obtained prepolymer chips. A solid-state polymerization chip was obtained from the prepolymer chip in the same manner as in Example 1. Table 2 shows the physical properties of the chips. From the solid-state polymerization chip, a heat-fixing bottle having a capacity of 1 l was obtained in the same manner as in Example 1. The physical properties of the bottle are shown in Table-3. Further, when continuous operation was performed in the same manner as in Example 1, white film-like deposits were observed on the mold, although the amount was slight. Further, in the heat filling test carried out in the same manner as in Example 1, deformation was observed in the entire bottle and a small amount of liquid was leaked from the spout.

[0036]

Comparative Example 4 Polymerization was carried out in the same manner as in Example 1 except that 0.35 kg of diethylene glycol (DEG) was added to the prepared slurry. Table 1 shows the physical properties of the obtained prepolymer chips. From the prepolymer chip, a solid-state polymerization chip and a heat-fixing bottle having a capacity of 1 l were obtained in the same manner as in Example 1. The physical properties of the chip and bottle are shown in Table-3. When continuous operation was performed in the same manner as in Example 1, white film-like deposits were found on the mold surface. Further, in the heat filling test carried out in the same manner as in Example 1, deformation was observed in the entire bottle and a small amount of liquid was leaked from the spout.

[0037]

Comparative Example 5 Polymerization was carried out in the same manner as in Example 1 except that the esterification time after the feed of the raw material slurry was 1 hour and 30 minutes. Table 1 shows the physical properties of the obtained prepolymer chips. From the prepolymer chips, Example 1
A solid-state polymerization chip and a heat-fixing bottle having a volume of 1 l were obtained in the same manner as in. The physical properties of the chip and bottle are shown in Table-3. The result of the hot filling test similar to that of Example 1 was good, but when the mold after the molding was observed as the continuous molding test, white film-like deposits were found on the mold.

[0038]

Comparative Example 6 Polymerization was carried out in the same manner as in Example 1 except that the esterification time after the feed of the raw material slurry was 30 minutes. The physical properties of the obtained prepolymer chips are shown in Table-
Shown in 1. From the prepolymer chip, a solid-state polymerization chip and a heat-fixing bottle having a capacity of 1 l were obtained in the same manner as in Example 1. The physical properties of the chip and bottle are shown in Table-3. The result of the hot filling test similar to that of Example 1 was good, but when the mold after the molding was observed as the continuous molding test, white film-like deposits were found on the mold.

[0039]

Comparative Example 7 Polymerization was carried out in the same manner as in Example 4 except that the esterification time after the feed of the raw material slurry was 30 minutes. Table 1 shows the analytical values of the obtained prepolymer chips. From the prepolymer chip, a solid-state polymerization chip and a heat-fixing bottle having a capacity of 1 l were obtained in the same manner as in Example 1. The physical properties of the chip and bottle are shown in Table-3. The result of the hot filling test similar to that of Example 1 was good, but when the mold after the molding was observed as the continuous molding test, white film-like deposits were found on the mold.

[0040]

Comparative Example 8 Polymerization was performed in the same manner as in Example 4 except that 1.37 g of antimony trioxide was used. Table 1 shows the physical properties of the obtained prepolymer chips. From the prepolymer chip, a solid-state polymerization chip and a heat-fixing bottle having a capacity of 1 l were obtained in the same manner as in Example 1. The physical properties of the chip and bottle are shown in Table-3. The result of the hot filling test similar to that of Example 1 was good, but when the mold after the molding was observed as the continuous molding test, white film-like deposits were found on the mold.

[0041]

Comparative Example 9 Polymerization was carried out in the same manner as in Example 1 except that 4.00 g of antimony trioxide was used and the polycondensation time was 2 hours and 10 minutes. Table 1 shows the physical properties of the obtained prepolymer chips. From the prepolymer chips, Example 1
A solid-state polymerization chip and a heat-fixing bottle having a volume of 1 l were obtained in the same manner as in. The physical properties of the chip and bottle are shown in Table-3. The result of the hot filling test similar to that of Example 1 was good, but when the mold after the molding was observed as the continuous molding test, white film-like deposits were found on the mold.

[0042]

EFFECT OF THE INVENTION The copolymerized polyester of the present invention has a low content of oligomers and is unlikely to cause mold contamination during molding.
Therefore, since it is not necessary to frequently wash the molding device when manufacturing the molded product, it is possible to improve the productivity of the molded product such as a bottle, a film or a sheet. Moreover, the copolyester of the present invention is excellent in heat resistance and mechanical strength and is suitable as a molding material for containers for fruit juice drinks requiring heat resistance.

[0043]

[Table 1]

[0044]

[Table 2]

[0045]

[Table 3]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical display location C08J 5/18 CFD 9267-4F // B29K 67:00 (72) Inventor Osamu Kishiro Yokohama, Kanagawa 1000, Kamoshida-cho, Midori-ku, Yokohama

Claims (4)

[Claims] 1. A copolymerized polyester containing terephthalic acid as a dicarboxylic acid component and ethylene glycol as a main component as a diol component, wherein (1) cyclohexanedimethanol is 0.5 to 3.5 mol% as the diol component, and diethylene glycol is used. Is 1.
0 to 2.5 mol%, (2) intrinsic viscosity of 0.60 to 1.50 dl / g, (3) antimony atom content of 150 to 300 p
pm, (4) the concentration of the terminal carboxyl groups is 18 eq / ton or less, (5) the ratio of the terminal carboxyl groups in the total terminal groups is 8 to 2
0 equivalent%, (6) The content of the cyclic trimer is 0.35 wt% or less, Copolymer polyester characterized by the following. 2. A copolymerized polyester having terephthalic acid as a dicarboxylic acid component and ethylene glycol as a main component as a diol component, wherein (1) cyclohexanedimethanol is 0.5 to 3.5 mol% as the diol component, and diethylene glycol is used. Is 1.
0-2.5 mol%, (2) intrinsic viscosity 0.50-0.70 dl / g, (3) antimony atom content 150-300 weight p
pm, (4) the concentration of the terminal carboxyl group is 15 to 30 eq / t
on, (5) The ratio of the terminal carboxyl groups in the total terminal groups is 12 to
The copolymerized polyester according to claim 1, which is produced by solid-phase polymerization of a prepolymer having an amount of 22 equivalent%. 3. A copolymer polyester hollow container obtained by subjecting the copolymer polyester according to claim 1 to preform molding by injection molding or extrusion molding, and then biaxially stretch blow molding. 4. A sheet material obtained by injection molding or extrusion molding of the copolymerized polyester according to claim 1.
A stretched film made of copolyester which is stretched in at least one direction.