JPS5855166B2 - Method for producing thermoplastic polyester copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has excellent mechanical properties such as low-temperature impact strength, tensile strength, and elongation, and is suitable for manufacturing molded products. The present invention relates to a method for producing a copolymer which is excellent as a hot-melt agent or a heat-sealing agent because of its excellent properties.

That is, the present invention provides a terephthalate unit (Y) obtained from terephthalic acid or its ester-forming derivative and 1,4-butanediol, an aromatic dicarboxylic acid other than terephthalic acid or its ester-forming derivative, and 1,4-
butanediol) and polyesters obtained from poly(tetramethylene oxide) glycol having a molecular weight of 400 to 6.000 and terephthalic acid and aromatic dicarboxylic acids other than terephthalic acid or their ester-forming derivatives. (tetramethylene oxide) Glycol dicarboxylate unit (x) is characterized by mixing and reacting each component so that the composition is surrounded by the points A'', B', C, and D in Figure 1. This is a method for producing a polyester/polyether block copolymer.

Polyester/polyether block copolymers mainly composed of terephthalic acid have been known and are useful as tough and low-temperature flexibility polymers, but on the other hand, they have a high melting temperature and poor thermal stability during melting. This is bad and has an unfavorable effect on melt molding.

Copolymerized polyesters using terephthalic acid and other dicarboxylic acids are also known, but these copolymers are glassy or starch syrup-like and lack toughness, and are useful as adhesives, etc., but they cannot be used in molded products. It is inappropriate for

However, since the block copolymer of the present invention melts at a relatively low temperature, it is not only easy to mold, but also has good thermal stability when melted, and the molded product obtained also has low-temperature impact strength, It has excellent mechanical properties such as tensile strength and extensibility.

Copolymers usually have lower melting temperatures than homopolymers;
The mechanical properties are also reduced, but it is surprising that the mechanical properties are hardly reduced as in the case of the copolymer of the present invention.

Furthermore, the copolymer of the present invention has good thermal stability when melted and the film is strong, so it is useful as a hot melt agent or a heat sealing agent.It also has good solubility in solvents, so it can be used as a solution type or It is also useful as an emulsion type paint and adhesive.

Examples of terephthalic acid or its ester-forming derivatives used in the present invention include terephthalic acid, dimethyl terephthalate, terephthalic acid diglycol ester, and terephthalic acid chloride.

The Y unit is obtained from the terephthalic acid component and the 1,4-butanediol component, but the ester unit other than the Y unit, that is, the Z unit, is obtained from the aromatic dicarboxylic component other than the terephthalic acid component and the 1,4-butanediol component. Consisting of

As aromatic dicarboxylic acid components other than terephthalic acid,
For example, isophthalic acid, phthalic acid, 1,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,7
Examples include -naphthalene dicarboxylic acid, 1,2-di(4-carboxyphenoxy)ethane, and bis(4-carboxyphenyl)sulfone.

Poly(tetramethylene oxide) glycol dicarboxylate units are formed by poly(tetramethylene oxide) glycol having a molecular weight of 400 to 6,000 and the above-mentioned aromatic dicarboxylic acids, that is, terephthalic acid and aromatic dicarboxylic acids other than terephthalic acid or esters thereof. and its derivatives.

The above-mentioned copolymer is obtained by combining the above-mentioned compounds and reacting them in a specific ratio, but the above-mentioned Yff component and Z component may be bonded randomly or block-bonded. However, they are usually combined randomly.

Considering the composition of the copolymer of the present invention, in Figure 1, the composition E or F contains many poly(tetramethylene oxide) glycol dicarboxylate units, so the initial modulus of the molded article is small. ,
-Lack of toughness and reduced resistance to thermal oxidation, resulting in poor thermal stability during melting as well as poor deterioration resistance at temperatures below the melting temperature.

The copolymer near H is poly(tetramethylene oxide)
Because it does not contain or contains only a small amount of glycol dicarboxylate units, it has a low elongation at yield, exhibits significant necking behavior, exhibits little behavior as a nidistomer, and has extremely poor low-temperature properties.

Further, copolymers near G have high melting points and are elastomers with excellent heat resistance, but they are not suitable for rotary molding, powder coating, etc. because of their high melting temperatures and poor heat resistance at molding temperatures.

It is also poorly soluble in common solvents, making it unsuitable for solvent processing.

Furthermore, the copolymer near ① has a low melting temperature, slow curing, and poor moldability due to the small amount of polytetramethylene terephthalate component.

The composition of the portion surrounded by points A'', B', C, and D of the present invention is within a preferable range because it has a relatively low melting temperature and good stability during melting.

The polymer of the present invention can be produced by conventional condensation polymerization methods.

A preferred method is dimethyl ester of terephthalic acid, 1,4
- As butanediol and other ester-forming derivatives, dimethyl esters of aromatic dicarboxylic acids other than terephthalic acid and poly(tetramethylene oxide) glycols were transesterified at about 150 to 240°C in the presence of a polycondensation catalyst. In this method, a polyester copolymer is obtained by heating the prepolymer to a high temperature, removing methanol formed by the transesterification reaction, and vacuum distilling excess low molecular weight alkylene glycol from the produced prepolymer.

In order to smoothly proceed with the above polymerization reaction, transesterification,
Preference is given to using polycondensation catalysts.

Particularly effective are zinc acetate-antimony trioxide,
Examples include magnesium acetate-antimony trioxide, calcium acetate-germanium dioxide, potassium titanyl oxalate, tetra-iso-propyl titanate, tetra-n-butyl titanate, magnesium hexabutoxyhydrodiene titanate, and the like.

Although the polymers of the present invention have many desirable properties as is, they can be further stabilized by adding various stabilizers.

Useful stabilizers include substituted benzophenones,
Examples include ultraviolet absorbers such as benzotriazole, antioxidants such as hindered phenols, thiodipropionic acid esters, aromatic amines and their derivatives, and hydrolysis stabilizers of polycarposisides.

Furthermore, antistatic agents, plasticizers, lubricants, flame retardants, etc. can be added to these polyester copolymers depending on the purpose.

Furthermore, these polyester copolymers contain inorganic or organic pigments, glass fibers, carbon fibers, asbestos,
It is also possible to modify the composition by adding powdered or fibrous fillers such as calcium carbonate, finely powdered silica, and talc.

In particular, they can increase the elastic modulus of the material.

The copolymer of the present invention usually has a melting point of 200°C or less,
Therefore, it has sufficient fluidity at a molding temperature of about 220°C.

Normally, this type of polymer has the disadvantage of rapidly deteriorating and becoming discolored when heated above 240°C in air, but the copolymer of the present invention has sufficient fluidity at temperatures below 220°C, so it does not deteriorate. Roll molding, press molding, calendar processing, melt casting molding, powder coating, etc. can be performed with almost no occurrence.

Furthermore, since the molten polymer cures quickly, it can be molded using various molding methods such as injection molding, extrusion molding, and blow molding.

Furthermore, the polymer of the present invention is capable of high frequency bonding.

In addition, the copolymer of the present invention not only dissolves in a solvent at a relatively high concentration and is suitable for various solvent processing, but also provides a stable emulsion, which enables emulsion processing, and can be used in a wide range of applications.

The present invention will be explained in more detail below using Examples.

In the present invention, the strength characteristics were measured by the following method.

(1) Crystal melting point The temperature was raised at a rate of 1° C./1 minute using a micro melting point measuring device (Natsumoto Seisakusho), and the temperature at which it became a dark field under a polarizing microscope was determined.

(2) Solution viscosity Using a mixed solvent of phenol nitetrachloroethane and 6:4 (weight ratio), the concentration is 0.2? /100cc at 30℃
The reduced specific viscosity was determined.

(3) Using a flow tester with a high flow start temperature, the hole diameter is 1 inch and the length is 1Q mm.
The temperature at which the discharge speed becomes 0.001 cni/sec when a pressure of 100 kg/crA is applied was measured.

(4) Tensile strength JIS K6301 method (5) Elongation at break Same as above (6) Brittle temperature Same as above (7) Surface hardness ASTM-DI484 method, JIS
K6301 method (8) Necking JI No. 83 dumbbell (thickness 2 cm x width 5 cm x length 10 cm
) was pulled at a pulling speed of 5QQmm/min, and the constriction at the center of the sample was visually determined.

Example 1 Poly(tetramethylene oxide) glycol 1050 parts Coal (average molecular weight 1250) ■,4-butanediol 4050 parts Dimethyl terephthalate 3780 parts Dimethyl isophthalate 2040 parts Tetrabutyl titanate 3.8 parts Ionox 330 (manufactured by Shell) 15 .1 part of the above substance was put into a polymerization pot to make polyester copolymer P1.
threatened.

The above substance was placed in an autoclave, purged with nitrogen, and then heated to bring the internal temperature to 250°C over 100 minutes.

During this time, methanol was distilled out due to the transesterification reaction.

After reaching 250°C, the pressure was gradually reduced to 0.1 mmHft or less for 100 minutes, and polycondensation was carried out.

Polycondensation under reduced pressure was completed in 120 minutes, and the polymer was extruded into a strand shape from an autoclave under nitrogen pressure, and after cooling, it was pelletized.

The solution viscosity of this product was ηsp/c=1.57 (molecular weight 23,000).

Comparative Example 1 1.4-Butanediol 1350 parts Dimethyl terephthalate 1260 // Dimethyl isophthalate 680 Tetrabutyl titanate 1.1 Ionox 330
4.4 // Comparative polymer Q1 was made from the above material.

The solution viscosity of this product was ηsp/c=1.31.

Table 1 shows the properties of polyester copolymer P1 and comparative polymer Q1.

The polyester copolymer of the present invention does not exhibit obvious necking, exhibits elastic behavior, and exhibits excellent low-temperature properties, but
The comparative polymer exhibits necking behavior under tension, exhibits no elasticity, and has poor low-temperature properties with an embrittlement temperature of -35°C.

Comparative Example 2 1Rike1Uyt-y-vyta''-IM)')
°”′ □.

5 parts (average molecular weight 1050) 1.4-butanediol 2025//dimethyl terephthalate 2910//tetrabutyl titanate 2.1 Polyester copolymer Q2 was prepared from the above materials according to the method of Example 1.

The solution viscosity of this product was ηsp/c=1.60.

Table 2 shows the properties of comparative polymer Q2.

Since comparative polymer Q2 exhibits necking behavior, it only exhibits elastic behavior when the strain is within 40% of the elongation at yield point.

Furthermore, comparative polymer Q2 needs to be molded at a high temperature of 220° C. or higher, and thermal oxidative deterioration is significant when exposed to air for a long time.

Furthermore, the heat-sealed portion of the film from Comparative Polymer Q2 turned white.

High frequency bonding was not possible.

Example 2, Comparative Example 3 Polyester copolymer P2 and comparative polymer Q2 were prepared from the above materials according to the method of Example 1.

The solution viscosity of P2 is 77 sp/c = 1.89 (molecular weight 24000), and that of Q3 is ηsp/c =
It was 2.03.

Table 3 shows the properties of P2 and Q3. Table 3 Comparative polymer Q3, which has too many polytetramethylene dicarboxylate units out of the scope of the present invention, has a low crystal melting point and flow initiation temperature, making it impractical.

Comparative Examples 4, 5 Comparative Polymer Q was prepared from the above materials according to the method of Example 1.
4. I made Q5.

The viscosity of each solution is ηsp/c = 2.23, 3
．． It was 06.

Their properties are shown in Table 4.

Table 4 Q4. Composition with too many poly(tetramethylene oxide) glycol dicarboxylate units. Since Q5 has a low surface hardness and a low initial modulus, its lack of toughness limits its uses and is not preferred.

Example 3 Poly(tetramethylene oxide) glycol (average molecular weight 1000) 1000 notes 1.
4-Butanediol 1800 parts Dimethyl terephthalate 1253 parts Dimethyl isophthalate 784 parts Tetrabutyl titanate 1.6 parts Ionox 330 6.3 parts Polyester copolymer P3 was synthesized from the above materials according to the method of Example 1.

The solution viscosity of this polymer was ηsp/c=2.20 (molecular weight about 26,000).

Example 4 Poly(tetramethoxy 1゛) □ o o o
s glycol (average molecular weight 1000) 1.4-butanediol 1800 parts Dimethyl terephthalate 1096 parts Dimethyl isophthalate 941 parts Tetrabutyl titanate 1.6 parts Ionox 330
6.3 parts Polymer P4 was made from the above materials according to the method of Example 1.

The solution viscosity of this polymer was ηsp/c-2.30 (molecular weight approximately 25,000).

The properties of polymers P3 and P4 are shown in Table 5.

P3. The molded product obtained from the polymer of P4 is Q4 'Q
Compared to No. 5, the initial modulus (stress at 100% elongation) is larger, the tear strength is stronger, and it is a tough material.

Example 5 Poly(tetramethylene oxide) glycol (average molecular weight 1ooo) 1000@11
．． 4-7 Butanediol 10,800 parts Dimethyl terephthalate 4,528 parts Dimethyl isophthalate 7,946 parts Tetrabutyl titanate 8 parts Ionox 330
32 parts Polymer P5 was synthesized from the above materials according to the method of Example 1.

The solution viscosity of this polymer was ηsp/c=1.52 (molecular weight 20,000).

Example 6 1000 parts Glycol (average molecular weight 1000) 1.4-Butanediol 13500 parts Dimethyl terephthalate 10087 parts Dimethyl isophthalate 5724 parts Tetrabutyl titanate 10 parts Ionox 330
Polymer P6 was synthesized from 39 parts of the above material according to the method of Example 1.

The melting viscosity of this polymer was ηsp/c=1.60 (molecular weight approximately 23,000).

Polymer P5. The composition of P6 was as follows.

Polymer P5. P6 and comparative polymer Q.

It is shown in Table 6.

The properties of the polymer of the present invention P5. P6 does not exhibit obvious necking, and thus exhibits nystomeric behavior with a recovery rate from stretching exceeding 50%.

Furthermore, the low-temperature embrittlement temperature is low.

On the other hand, comparative polymer Q1 exhibits a significant necking phenomenon.

Therefore, the recovery rate from elongation beyond the yield point is extremely poor and it is difficult to call it a nidistomer.

Furthermore, the low-temperature embrittlement temperature is high and the low-temperature properties are poor.

Comparative Example 6 Poly(te1ramethyl oxide) 107 H glycol (average molecular weight 975) 1,4-butanediol 300 parts Dimethyl terephthalate 364.5 parts Dimethyl isofucrate 36.5 parts Tetrabutyl titanate 4 parts 8'-'- β-f 7 f)
Ii -p -7'' 2-Part Nylene Diamine Polymer Q6 (
(molecular weight approximately 23,000) was synthesized.

The composition and properties of Polymer Q6 are shown in Table 7.

Although Comparative Polymer Q6 is a material with a high melting point and high strength, the heat-sealed portion of the film made from this polymer turned white and high-frequency bonding was impossible.

On the other hand, with the polymer P1 of the present invention, sheet sealing was possible without whitening, and high frequency bonding was also easily possible.

[Brief explanation of the drawing]

Figure 1 is a triangular diagram showing the three precepts of the present invention: a terephthalate unit (Y), an ester unit of an aromatic dicarboxylic acid other than terephthalic acid (Z), and a poly(tetramethylene oxide) glycol dicarboxylate unit (X). It is a coordinate.

Claims (1)

[Scope of Claims] 1. Terephthalic acid or its ester-forming derivative; and 1.
, 4-butanediol and an aromatic dicarboxylic acid other than terephthalic acid or its ester-forming derivative and ester unit (Z) obtained from 1°4-butanediol and a molecular weight of 400 to 6.
The composition of the poly(tetramethylene oxide) glycol dicarboxylate unit (X) obtained from ,000 poly(tetramethylene oxide) glycol and terephthalic acid and an aromatic dicarboxylic acid other than terephthalic acid or an ester-forming derivative thereof is A method for producing a thermoplastic polyester copolymer, which comprises blending and reacting each component so as to form a portion surrounded by points A", B', C, and D in FIG. 1.