JPH04270727A - Polyester composition - Google Patents

Abstract

PURPOSE:To obtain a polyester composition suitable for forming film. CONSTITUTION:A polyester composition obtained by polycondensing an aromatic dicarboxylic acid with glycol in the presence of an antimony compound, titanium compound, germanium compound, phosphorus compound and glycol-soluble magnesium compound having an amount simultaneously satisfying the following formulas (1) to (5) and having specific resistance in melting being in the range of 1X10<6> to 1X10<8>:(1) 0<=Sb<=0.5; (2) 0<=Ti<=0.4; (3) 0<=Ge<=1.5; (4) 0.3<=Mg<=3.0; (5) 0.05<=P/Mg<=0.5 (wherein Sb, Ti, Ge, Mg and P represent mol number of each element per 10<6>g of polyester composition produced).

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is a polyester composition that has extremely few internal precipitates caused by catalysts, has an extremely small number of coarse protrusions on the film surface when formed into a film, and can be used as a raw material for films with excellent surface properties and transparency. relating to things.

0002

[Prior art and problems to be solved by the invention] Polyesters represented by polyethylene terephthalate are
Taking advantage of its excellent mechanical properties, electrical properties, chemical resistance, and dimensional stability, it is used as a base film in many fields such as magnetic recording, capacitors, packaging, plate making, electrical disconnection, and photography. It is being When these polyesters are applied to high-density recording base films, such as vapor-deposited video tapes, the film surface is particularly required to have flatness. In order to achieve this flatness, the film surface must be free of not only coarse protrusions but also relatively small protrusions. Also,
When applied to photolithographic films, particularly high transparency is required.

The cause of these film surface protrusions and loss of film transparency is that catalysts added during polyester production, particularly antimony compounds, precipitate in the polyester. This precipitate is a reaction product of antimony alone or a phosphorus compound added to improve thermal stability. When an antimony compound is used, the polymerization rate is fast and the resulting polyester has excellent physical properties such as thermal stability, color tone, amount of terminal carboxyl groups, and softening point, but as mentioned above, precipitates occur in the polyester. It has the disadvantage of

In addition to the above-mentioned antimony compounds, titanium compounds, germanium compounds, and the like are typically known as polyester polymerization catalysts. When a titanium compound is used, the polymerization rate is extremely fast and there is no formation of precipitates such as antimony, but the resulting polyester has poor thermal stability and a strong yellowish color tone. When a germanium compound is used, there is no formation of precipitates and the color tone is excellent, but the resulting polyester has a low softening point and has the disadvantage that when formed into a film, the mechanical strength of the film is reduced.

During polyester polymerization production, it is common practice to add phosphorus compounds to improve the color tone and thermal stability of polyester, but phosphorus compounds react with most polymerization catalysts. This has problems such as reducing the activity of the catalyst and generating precipitates. In particular, titanium compounds are highly deactivated by phosphorus compounds.

[0006]

[Means for Solving the Problems] In view of the above-mentioned problems, the present inventors have made extensive studies and found that a polyester composition obtained under certain specific conditions has excellent properties, and has completed the present invention. I ended up doing it. That is, the gist of the present invention is to polycondensate an aromatic dicarboxylic acid and a glycol in the presence of an antimony compound, a titanium compound, a germanium compound, a phosphorus compound, and a glycol-soluble magnesium compound in an amount that simultaneously satisfies the following formulas (■ to ■). The specific resistance at the time of melting obtained by
The polyester composition lies in the range of 1×10 8 .

0≦Sb≦0.5
...■0≦Ti≦0.4
...■0≦Ge≦1.5
...■0.3≦Mg≦3.0
...■0.05≦P/Mg≦0.5
...■ (In the above formula, Sb, Ti, Ge, M
g and P are the produced polyester composition 106 of each element.
The present invention will be described in detail below. Polyester as used in the present invention refers to terephthalic acid, isophthalic acid, naphthalene.
Obtained by performing an esterification reaction using an aromatic dicarboxylic acid component such as 2,6-dicarboxylic acid and a glycol component such as ethylene glycol, diethylene glycol, neopentyl glycol, etc. as starting materials, and then performing a polycondensation reaction. Direct polymerization polyester.

Specific examples of such polyester include polyethylene terephthalate and polyethylene-2,6-naphthalate, but even if it is a homopolymer,
It may also be a copolymer of a third component. Examples of the antimony compound used in the present invention include antimony trioxide and antimony pentoxide.
It is 0.5 mol or less, preferably 0.1 mol or less per g. If the amount of the antimony compound used is more than 0.5 mol, precipitates due to antimony will be generated in the obtained polyester, causing coarse foreign matter, which is not preferable.

[0009] The titanium compounds used in the present invention include:
Examples include organic titanium compounds such as tetraethoxytitanium and tetra-n-butyl orthotitanate, and inorganic titanium compounds such as titanium sulfate and titanium chloride.
Polyester composition 106 obtained as titanium element
It is 0.4 mol or less, preferably 0.2 mol or less per g. If the amount of the titanium compound used exceeds 0.4 mol, the color tone of the resulting polyester may be impaired or the thermal stability may be deteriorated.

Examples of the germanium compound used in the present invention include germanium dioxide, germanium chloride, and germanium phosphite.
It is not more than 1.5 mol per g, preferably not more than 0.5 mol. If the amount of the germanium compound used exceeds 1.5 mol, the softening point of the obtained polyester will decrease, which is not preferable.

[0011] Magnesium compounds used in the present invention include glycol-soluble compounds such as magnesium acetate, magnesium oxalate, and magnesium chloride.
The amount of magnesium used is in the range of 0.3 to 3.0 mol, preferably 0.5 to 2.0 mol, per 106 g of the resulting polyester composition. If the amount of the magnesium compound used is less than 0.3 mol, the polymerization rate of the polyester will be extremely slow, making it impractical, and the specific resistance of the resulting polyester during melting will increase, reducing the film formability of the polyester film. I don't like it. In addition, the amount of magnesium compound used is 3.0
If the amount exceeds the molar amount, the color tone of the resulting polyester may be impaired or the thermal stability may be reduced.

Examples of the phosphorus compound used in the present invention include trialkyl esters such as trimethyl phosphate and triethyl phosphate, acidic phosphoric acid esters such as methyl acid phosphate and ethyl acid phosphate, and phosphoric acid. One or more selected types can be used. The amount of phosphorus compound used is 0.05≦P/Mg≦0.5, preferably 0.
．． The range is 1≦P/Mg≦0.2 (P indicates the number of moles of phosphorus element per 10 6 g of polyester, and Mg indicates the number of moles of magnesium element per 10 6 g of produced polyester). If the P/Mg ratio is less than 0.05, the color tone of the polyester obtained may be impaired or the thermal stability may be reduced. Furthermore, if the P/Mg ratio exceeds 0.5, the polymerization rate of the polyester will be extremely slow, making it impractical, and the specific resistance value of the obtained polyester when melted will also increase, so, for example, when processing it into a polyester film, This will cause inconvenience.

[0013] In the present invention, the antimony compound, germanium compound, titanium compound, magnesium compound, and phosphorus compound are added usually when the esterification reaction is substantially completed and the reaction rate is 80% or more, preferably. When it reaches 90% or more. Note that the antimony compound may be added before the start of the esterification reaction.

The specific resistance of the polyester composition of the present invention when melted is in the range of 1×10 6 to 1×10 8 Ω·cm, preferably 3×10 6 to 5×10 7 Ω·cm. If the resistivity is less than 1×10 6 Ω·cm, the thermal stability of the polymer will deteriorate, making it difficult to process the polymer, for example. On the other hand, if the specific resistance exceeds 1 x 108 Ωcm, the film forming speed will be low even if the electrostatic cooling method (high-speed manufacturing method for unstretched sheets described in Japanese Patent Publication No. 37-6142 etc.) is used. It becomes difficult to raise the temperature, and the productivity of the film becomes extremely poor.

The polyester composition of the present invention can be made into a film, for example, as follows. That is, the polyester composition of the present invention is melt-extruded, made into an unstretched sheet on a rotating cooling drum (preferably combined with the above-mentioned electrostatic application cooling method), and stretched at 80 to 130°C for 2 to 10 minutes in the machine direction.
Stretched 2 to 10 times in the transverse direction at 80 to 140°C, sequentially or simultaneously, stretched again if necessary, and then stretched to 160 to 140°C.
It can be formed into a film by heat treatment at 240°C. In addition, in order to impart slipperiness and abrasion resistance to the molded product obtained from the polyester composition of the present invention, inorganic particles such as silicon dioxide, titanium dioxide, alumina, and organic particles such as crosslinked polymers are added during polyester production. may be added.

[0016]

[Examples] The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited to the following Examples. The methods for evaluating the physical properties and characteristics of the polyester composition of the present invention and the film obtained therefrom are as follows. In addition, in the examples, "part" means "
Parts by weight.

(1) Polymerization rate of polyester The polymerization rate of polyester was determined by determining the polymerization time until the value of the intrinsic viscosity [η] of the polyester reached 0.65, and was used as an index of the polymerization rate. (2) Intrinsic viscosity of polyester [η] 1 g of polymer is phenol/tetrachloroethane = 50
/50 (weight ratio) dissolved in 100 ml of mixed solvent,
Measured at 30°C.

(3) Polyester thermostable polymer 5
g was placed in a glass test tube, dried under vacuum at 160°C for 2 hours, and then melted at 290°C for 2 hours under a nitrogen atmosphere. The intrinsic viscosity [η] of the polymer before melting was measured. Evaluation was made based on the rate of decrease in the intrinsic viscosity [η].

(4) Specific resistance of polyester when melted as described in British Journal of Applied Physics (Brit. J. Appl. Phys.) Vol. 17, pp. 1149-1154 (1966) Followed the method. However, in this case, the temperature at the time of melting the polymer was 290° C., and the value immediately after applying a direct current of 3000 V was taken as the specific resistance at the time of melting.

(5) Polyester solution haze 2.7 g of polymer was mixed with phenol/tetrachloroethane = 60/4.
0 (weight ratio), heated and dissolved at approximately 130°C for 1 hour, cooled, collected the solution into a 10 mm thick cell made of quartz glass, and placed it in an integrating sphere haze meter (
550nm by Nippon Precision Optical Co., Ltd. (SR type)
The turbidity (%) when measured at the wavelength of was defined as the solution haze.

(6) Polyester color tone Tokyo Denshoku Co., Ltd.
Measured according to the method of JIS Z-8722 using Color Analyzer TC-1800MKII model manufactured by B.
The value was determined and used as an index of color tone. (7) Film forming speed of polyester film Polyester was melt extruded using an extruder and an unstretched sheet was formed on a rotating cooling drum using an electrostatic cooling method. At this time, the film forming speed was defined as the speed at which the film could be formed without trapping bubbles, that is, the maximum rotational speed of the cooling drum.

(8) Number of coarse protrusions on the film surface: Evaporate aluminum on the film surface and use a two-beam interference microscope to calculate the number of n-th order interference fringes observed at a measurement wavelength of 0.54 μm per 25 cm2. and showed. The number of protrusions of primary or higher order is indicated as F1, and the number of protrusions of secondary or higher order is indicated as F2.

Example 1 In the presence of 100 parts of bis-(β-hydroxyethyl) terephthalate oligomer, 87 parts of terephthalic acid and 42 parts of ethylene glycol were reacted at 260° C. under normal pressure to carry out an esterification reaction. Four hours after the start of the reaction, a polyester oligomer with an esterification rate of 97% was obtained. Next, 0.01 part of antimony trioxide, 0.0441 part of magnesium acetate tetrahydrate, and 0.0056 part of triethyl phosphate were added to 103 parts of the obtained polyester oligomer (corresponding to 100 parts of polyester), and the mixture was heated at 250°C to 28°C.
While raising the temperature to 5℃ in 120 minutes, the vacuum level is 760m at the same time.
The pressure was reduced from mHg to 1 mmHg in 120 minutes, and then a polycondensation reaction was performed at 285° C. and 1 mmHg to obtain a polyester. At this time, the intrinsic viscosity of polyester [η
] It took 245 minutes for polymerization to reach 0.65. The obtained polyester was good in terms of thermal stability, specific resistance during melting, solution haze, color tone, number of coarse protrusions, etc.

Example 2 A polyester was obtained in the same manner as in Example 1 except that the amount of antimony trioxide added was changed to 0.005 part. Example 3 A polyester was obtained in the same manner as in Example 1, except that the amount of antimony trioxide was changed to 0.0025 parts and 0.00142 parts of tetra-n-butyl orthotitanate was added. Example 4 Except for changing the amount of antimony trioxide to 0.0025 parts and adding 0.0025 parts of germanium dioxide,
Polyester was obtained in the same manner as in Example 1.

Example 5 Antimony trioxide was not added and tetra-orthotitanate was used.
A polyester was obtained in the same manner as in Example 1 except that 0.00355 parts of n-butyl was added. Example 6 Antimony trioxide was not added and germanium dioxide was added.
A polyester was obtained in the same manner as in Example 1 except that 0.005 parts was added.

Comparative Example 1 A polyester was obtained in the same manner as in Example 1, except that 0.035 part of antimony trioxide was added. Although the obtained polyester had a short polymerization time, it had a high solution haze and a large number of coarse protrusions after being formed into a film. Comparative Example 2 A polyester was obtained in the same manner as in Example 1, except that 0.00441 part of magnesium acetate tetrahydrate and 0.00056 part of triethyl phosphate were used. The obtained polyester had a high specific resistance when melted, and also required a long polymerization time.

Comparative Example 3 Example 1 except that magnesium acetate tetrahydrate was used in an amount of 0.0882 parts and triethyl phosphate was added in an amount of 0.0112 parts.
Polyester was obtained in the same manner as above. The obtained polyester was inferior in terms of thermal stability and color tone. Comparative Example 4 A polyester was obtained in the same manner as in Example 1, except that triethyl phosphate was used in an amount of 0.021 part. Although the obtained polyester had relatively good physical properties, the polymerization rate was slow and it was not practical.

Comparative Example 5 0.00355 parts of tetra-n-butyl orthotitanate,
Example 1 except that magnesium acetate tetrahydrate was 0.0041 part and triethyl phosphate was 0.00056 part.
Polyester was obtained in the same manner as above. The obtained polyester had a high specific resistance when melted. Comparative Example 6 Antimony trioxide was not added, and tetra-orthotitanate was added.
A polyester was obtained in the same manner as in Example 1 except that 0.0142 parts of n-butyl was added. The obtained polyester had poor thermal stability.

Comparative Example 7 Antimony trioxide was not added and germanium dioxide was added at 0.
A polyester was obtained in the same manner as in Example 1 except that 02 parts of polyester were added. The obtained polyester had poor thermal stability. The results obtained above are summarized in Table 1 below.

[0030]

[Table 1]

[0031]

[Effects of the Invention] The polyester composition of the present invention has very little precipitate caused by the catalyst, is useful as a film raw material, and has high industrial value.

Claims (1)

[Claims] [Claim 1] An antimony compound, a titanium compound, a germanium compound, in an amount that simultaneously satisfies the following formulas ■ to ■.
It is obtained by polycondensing aromatic dicarboxylic acid and glycol in the presence of a phosphorus compound and a glycol-soluble magnesium compound, and has a specific resistance of 1×1 when melted.
Polyester compositions ranging from 06 to 1 x 108. 0≦Sb≦0.5 ・・・■
0≦Ti≦0.4 ・・・■
0≦Ge≦1.5 ・・・■
0.3≦Mg≦3.0...
・■0.05≦P/Mg≦0.5 ・・
...■ (In the above formula, Sb, Ti, Ge, Mg and P indicate the number of moles of each element per 10 g of the produced polyester composition)