JPH04285631A - Thermoplastic polyester elastomer - Google Patents

Abstract

PURPOSE:To provide the subject elastomer comprising polyester hard segments and polyoxyalkylene glycol soft segments and having a high elongation recovery rate and excellent resilience, low temperature stability, mechanical strength and transparency. CONSTITUTION:The objective elastomer is composed of (A) hard segments comprising (i) a dicarboxylic acid or an ester-forming derivative thereof, (ii) 30-94mol% (based on all diol compounds) of ethylene glycol or butanediol and (iii) 1-50mol% (based on all diol compounds) of a diol of the formula (R is ethylene; X, Y are integers satisfied with an inequality of 2<=X+Y<=6) such as bisphenol A-ethylene oxide adduct, and (B) 5-50mol% (based on all diol components) of a polyoxyalkylene glycol preferably having a number-average mol.wt. of 300-20000.

Description

[Detailed description of the invention]

0001

TECHNICAL FIELD The present invention relates to a thermoplastic polyester elastomer, and more particularly to a thermoplastic polyester elastomer having an excellent elongation recovery rate and comprising a polyester hard segment and a polyoxyalkylene glycol soft segment.

0002

[Prior Art] In general, thermoplastic polyester elastomers are block polyether polyesters made by copolymerizing polyethylene terephthalate units or polybutylene terephthalate units as hard segments that develop rigidity, and polyether glycol as soft segments that develop elasticity. be.

[0003] This thermoplastic polyester elastomer can be used in a wide range of applications, from soft rubber-like resins to hard resins used in engineering plastics, etc. by freely changing the blending ratio of hard segments and soft segments. It is possible to do so. In addition, thermoplastic polyester elastomers have mechanical properties and chemical resistance comparable to ordinary polyester resins, and even when the proportion of soft segments increases,
It is a resin with excellent properties such as a relatively high melting point and high impact resilience.

0004

[Problems to be Solved by the Invention] However, as the proportion of soft segments increases in conventional thermoplastic polyester elastomers, the elongation recovery rate decreases, making it difficult to mechanically perform elasticity as an elastomer for molding materials. This had problems such as deterioration of characteristics.

[0005]

[Means for Solving the Problems] In view of the above circumstances, the present inventors have conducted intensive studies on thermoplastic polyester elastomers, and have found that a specific diol can be copolymerized as a diol component constituting a polyester hard segment. The inventors have discovered that the elongation recovery rate of thermoplastic polyester elastomers can be significantly improved, and have arrived at the present invention.

That is, the thermoplastic polyester elastomer of the present invention contains a dicarboxylic acid or its ester-forming derivative, 30 to 94 mol% of ethylene glycol or butanediol in the total diol component, and a diol having the structure shown in Formula 2. It is characterized in that it contains 1 to 50 mol% of the total diol component, and 5 to 50 mol% of polyoxyalkylene glycol in the total diol component.

[0007]

[Case 2]

(In the formula, R is an ethylene group, and X and Y are integers satisfying 2≦X+Y≦6.) The molecular chain of the thermoplastic polyester elastomer of the present invention consists essentially of polyester units. It is composed of polyether units, with the polyester units acting as hard segments exhibiting rigidity, and the polyether units acting as soft segments exhibiting elasticity.

[0009] In the present invention, the polyester unit constituting the hard segment contains an acid component mainly composed of dicarboxylic acid or its ester-forming derivative, and a diol having the structure shown by chemical formula 1 such as ethylene glycol or butanediol as the main components. It is obtained by condensation polymerization of diol components.

The dicarboxylic acids or ester-forming derivatives thereof used in the present invention include terephthalic acid, isophthalic acid, naphthalene-1,4- or -2-,
Examples include, but are not limited to, carboxylic acids such as 6-dicarboxylic acid, and ester-forming derivatives thereof such as dialkyl esters and diaryl esters, and other dicarboxylic acids such as glutaric acid, adipic acid, sebacic acid, Oxalic acid, succinic acid, or derivatives thereof such as dialkyl esters and diaryl esters can also be used depending on the intended use of the thermoplastic polyester elastomer. In the present invention, terephthalic acid, naphthalene-2,6-dicarboxylic acid, or ester-forming derivatives thereof are particularly preferred, and 50% of the total acid component is
It is preferable that the content is mol % or more. This is because if less than 50 mol% of terephthalic acid, naphthalene-2,6-dicarboxylic acid, or their ester-forming derivatives are contained in the total acid components, heat resistance may be lowered.

Further, ethylene glycol or 1,4-butanediol, which is used as the diol component constituting the polyester unit of the present invention, is preferably contained in a range of 30 to 94 mol % in the total diol component. This is because if the content of these diols is less than 30 mol%, the reactivity during polymerization and elasticity will decrease;
This is because if it exceeds mol%, the proportion of soft segments decreases and flexibility decreases.

Furthermore, in the present invention, it is necessary to contain a specific diol having the structure shown in Formula 1 as a diol component constituting the polyester unit. Specific examples of diols used include bisphenol A ethylene oxide adducts. These diols are preferably contained in an amount of 1 to 50 mol%, more preferably 2 to 30 mol%, in the total diol component. This is because if the content of these diols is less than 1 mol%, the expression of rigidity by the hard segment will decrease, and the impact resilience and elongation recovery rate will decrease, whereas if the content exceeds 50 mol%, the mechanical properties will decrease. It is. Further, it is preferable that the molar ratio of these diols to polyoxyalkylene glycol is in the range of 5:1 to 1:5 in terms of the balance between flexibility and elongation recovery rate of the elastomer.

[0013] Examples of the polyoxyalkylene glycol which is the soft segment constituting the thermoplastic polyester elastomer of the present invention include polyoxytetramethylene glycol and polyethylene glycol, which may be used alone or in combination. It's okay. In the present invention, polyoxyalkylene glycol is contained in a range of 5 to 50 mol%, preferably 8 to 30 mol%, in the total diol component. This is because if polyoxyalkylene glycol is less than 5 mol% of the total diol component, the soft segment will not exhibit elasticity, and if it exceeds 50 mol%, the resulting thermoplastic polyester elastomer will become an extremely flexible resin. , because it is not suitable for practical use.

[0014] Furthermore, the polyoxyalkyl glycol used in the present invention has a number average molecular weight of 300 to 20.
A value in the range of 000 is preferred. This is because when a polyoxyalkylene glycol with a number average molecular weight of less than 300 is used, the heat resistance and elastic modulus decrease, and the number average molecular weight is less than 2.
This is because if it exceeds 0,000, the compatibility with the hard segment becomes poor. In the present invention, when polyoxytetramethylene glycol is used as the polyoxyalkylene glycol, its number average molecular weight is 60
A number average molecular weight of 0 to 3,000 is preferred, and when polyethylene glycol is used, a number average molecular weight of 800 to 20,000 is preferred.

In the present invention, these diol components are added at the time of preparation in a range of 110 to 220 mol % based on the acid component, but other diol components such as neopentyl glycol, 1,6-cyclohexane An appropriate amount of dimethanol or the like may be added as a diol component.

Furthermore, in the present invention, for the purpose of accelerating the reaction rate during polymerization and increasing the melt viscosity of the final polymer, a trivalent or higher polyhydric carboxylic acid or a trivalent or higher polyhydric alcohol is added to the acid. It may be added in an amount of 0.01 to 5 mol% based on the components. The trivalent or higher polyhydric carboxylic acids or trivalent or higher polyhydric alcohols used include trimellitic acid, trimellitic anhydride, trimethylolpropane,
Examples include glycerin and the like.

The thermoplastic polyester elastomer of the present invention can be produced by known polyester production methods such as a direct polymerization method in which a dicarboxylic acid and a diol are directly reacted, and a transesterification method in which a dicarboxylic acid lower alkyl ester is reacted with a diol. can. Examples of catalysts used in the production of the thermoplastic polyester elastomer of the present invention include organic titanium compounds such as titanium tetrabutoxide, zinc acetate, magnesium acetate, cobalt acetate, germanium dioxide, and antimony trioxide. It is added in a range of 100 to 1000 ppm. When using 1,4-butanediol as the diol component, it is preferable to use an organic titanium compound, and when using ethylene glycol, it is preferable to use magnesium acetate, zinc acetate, manganese acetate, cobalt acetate, or antimony trioxide. Further, for the purpose of stabilizing the quality and improving the performance of the thermoplastic polyester elastomer, an appropriate amount of a stabilizer such as trimethyl phosphate may be added during production.

[0018]

[Function] The thermoplastic polyester elastomer of the present invention has a high elongation recovery rate by containing a diol having a specific structure such as bisphenol A ethylene oxide adduct in a predetermined content. be able to.

[0019]

EXAMPLES The present invention will be specifically explained below using examples. The intrinsic viscosity in the examples is 1,1 with phenol.
, 2,2,-tetrachloroethane were dissolved in a solvent mixed at a weight ratio of 1:1, and the solution was measured at 25° C. using an Ubbelohde viscometer. Glass transition point (Tg) and melting point (Tm)
was measured using a differential scanning calorimeter (Shimadzu DS40).
A sample melt-quenched at 0°C was measured at a heating rate of 5°C/min, and Tg was the shoulder value and Tm was the peak value. The elongation recovery rate is calculated by elongating a test piece with a diameter of 1 mm and a length of 200 mm to 200% at a temperature of 25°C, then removing the load and measuring the length of the recovered test piece. Calculated based on equation 3.

[0020]

[Chemical formula 3]

Example 1 206 parts by weight of terephthalic acid, 88 parts by weight of ethylene glycol.
4 parts by weight of bisphenol A ethylene oxide adduct, 4.2 parts by weight of bisphenol A ethylene oxide adduct, and 62 parts by weight of polyoxytetramethylene glycol having a number average molecular weight of 1000 are placed in a reaction vessel, heated and melted, and the generated moisture is removed to perform esterification. The temperature was raised to 240°C over about 4 hours from the start of the reaction. Next, 0.08 parts by weight of trimethyl phosphate was added, and 10 minutes later, 0.11 parts by weight of antimony trioxide was added, and the temperature was increased from 760 mmHg to 3
The pressure was reduced to below mmHg, and polycondensation was carried out at 280° C. for about 4 hours. The composition and physical properties of the obtained thermoplastic polyester elastomer are shown in Table 2. Table 1 shows the charging composition when the mixture was placed in the reaction vessel.

Example 2 136.7 parts by weight of dimethyl terephthalate, 69.7 parts by weight of 1,4-butanediol, 23.4 parts by weight of bisphenol A ethylene oxide adduct, number average molecular weight 10
00 polyoxytetramethylene glycol 140.8
parts by weight and 0.13 parts by weight of titanium tetrabutoxide are placed in a reaction vessel, heated and melted, methanol is removed and transesterification is carried out, and 2
After the temperature was raised to 40°C and the distillation of methanol was completed, 2
From 760mmHg to 3mmHg while increasing the temperature to 45℃
Polycondensation was carried out for about 4 hours under reduced pressure. The composition and physical properties of the obtained thermoplastic polyester elastomer are shown in Table 2. Table 1 shows the charging composition when the mixture was placed in the reaction vessel.

Example 3 Dimethyl naphthalene dicarboxylate 167.4 parts by weight, 1
, 64.2 parts by weight of 4-butanediol, 13.7 parts by weight of bisphenol A ethylene oxide adduct, 123.4 parts by weight of polyethylene glycol having a number average molecular weight of 600, and 0.05 parts by weight of titanium tetrabutoxide were placed in a reaction vessel. After heating and melting, methanol is removed and transesterification is performed, and the temperature is increased to 220°C over about 3 hours from the start of the reaction.
After the distillation of methanol is completed, the temperature is raised to 265℃.
Polycondensation was carried out for about 3 hours by reducing the pressure from 760 mmHg to 3 mmHg or less while raising the temperature to 3 mmHg. The composition and physical properties of the obtained thermoplastic polyester elastomer are shown in Table 2. Table 1 shows the charging composition when the mixture was placed in the reaction vessel.

Example 4 152.7 parts by weight of dimethyl naphthalene dicarboxylate, 1
, 4-butanediol 56.4 parts by weight, number average molecular weight 1
000 polyoxytetramethylene glycol 62.6
Part by weight, bisphenol A ethylene oxide adduct 1
03.8 parts by weight of titanium tetrabutoxide and 0.04 parts by weight of titanium tetrabutoxide were placed in a reaction vessel, heated and melted, methanol was removed and transesterification was performed, and the temperature was raised to 220°C over about 4 hours from the start of the reaction. After completing the distillation of methanol, the temperature was increased from 760 mmHg to 3
The pressure was reduced to below mmHg and polycondensation was carried out for about 4 hours. The composition and physical properties of the obtained thermoplastic polyester elastomer are shown in Table 2. Table 1 shows the charging composition when the mixture was placed in the reaction vessel.

Example 5 83.3 parts by weight of dimethyl terephthalate, 38.7 parts by weight of 1,4-butanediol, 14.2 parts by weight of bisphenol A ethylene oxide adduct, number average molecular weight 100
214.6 parts by weight of polyoxytetramethylene glycol 0.0, 0.16 parts by weight of trimellitic anhydride, and 0.08 parts by weight of titanium tetrabutoxide were placed in a reaction vessel, heated and melted, and methanol was removed to form the ester. After exchange, the temperature was raised to 220°C over about 4 hours from the start of the reaction.
After the distillation of methanol was completed, the pressure was reduced from 760 mmHg to 3 mmHg or less while increasing the temperature to 245°C, and polycondensation was carried out for about 4 hours. The composition and physical properties of the obtained thermoplastic polyester elastomer are shown in Table 2. Table 1 shows the charging composition when the mixture was placed in the reaction vessel.

Comparative Example 1 61.4 parts by weight of dimethyl terephthalate, 17.1 parts by weight of 1,4-butanediol, 253.1 parts by weight of polyoxytetramethylene glycol having a number average molecular weight of 1000, and 0.06 parts by weight of titanium tetrabutoxide. After heating and melting the mixture, methanol was removed and transesterification was carried out, and the temperature was raised to 220°C over about 4 hours from the start of the reaction, and after the methanol distillation was completed, the temperature was raised to 245°C. Polycondensation was carried out for about 4 hours by reducing the pressure from 760 mmHg to 3 mmHg or less while increasing the temperature. The composition and physical properties of the obtained thermoplastic polyester elastomer were
Shown in the table. Table 1 shows the charging composition when the mixture was placed in the reaction vessel.

Comparative Example 2 Dimethyl naphthalene dicarboxylate 158.1 parts by weight, 1
, 39 parts by weight of 4-butanediol, 150.5 parts by weight of bisphenol A ethylene oxide adduct, polyoxytetramethylene glycol 19 with a number average molecular weight of 1000.
．． 4 parts by weight, and 0.05 parts by weight of titanium tetrabutoxide were placed in a reaction vessel, heated and melted, methanol was removed and transesterification was carried out, the temperature was raised to 220°C over about 4 hours from the start of the reaction, and methanol After the distillation of
From 760mmHg to 3mmH while increasing the temperature to 245℃
Polycondensation was carried out for about 4 hours under reduced pressure until the pressure was below 1.5 g. The composition and physical properties of the obtained thermoplastic polyester elastomer are shown in Table 2. Table 1 shows the charging composition when the mixture was placed in the reaction vessel.

Comparative Example 3 20.9 parts by weight of dimethyl terephthalate, 83.8 parts by weight of dimethyl isophthalate, 17 parts by weight of ethylene glycol, 15 parts by weight of bisphenol A ethylene oxide adduct
2 parts by weight, 80.9 parts by weight of polyoxytetramethylene glycol with a number average molecular weight of 1000, and 0.0 parts by weight of manganese acetate.
After putting 5 parts by weight into a reaction container and heating and melting, the generated moisture is removed and esterification is performed.
The temperature was raised to 240°C over time. Next, 0.03 parts by weight of trimethyl phosphate was added, and 10 minutes later, 0.05 parts by weight of antimony trioxide was added, and the pressure was reduced from 760 mmHg to 3 mmHg or less while increasing the temperature to 280°C. Although polycondensation was carried out for 4 hours, the degree of polymerization stopped increasing midway through the reaction and an elastomer could not be obtained. Table 1 shows the charging composition when the mixture was placed in the reaction vessel.

[0029]

[Table 1]

[0030]

[Table 2]

The thermoplastic polyester elastomers of Examples 1 to 5 of the present invention exhibit high elongation recovery rates as shown in Table 2, and in particular, the thermoplastic polyester elastomers of Examples 1 to 3 have a high elongation recovery rate of over 95%. It shows an excellent elongation recovery rate. Further, the thermoplastic polyester elastomers of Examples 1 to 5 are also excellent in rebound modulus, low temperature stability, mechanical strength, and transparency. On the other hand, the thermoplastic polyester elastomers of Comparative Examples 1 to 3 all showed elongation recovery rates of less than 60%.

[0032]

Effects of the Invention The thermoplastic polyester elastomer of the present invention has a high elongation recovery rate, as well as excellent rebound modulus, low-temperature stability, mechanical strength, and transparency, and is suitable for industrial, food, medical, and textile applications. It can be used in a wide range of applications such as molding materials, packaging materials, and adhesive materials.

Claims (3)

[Claims] [Claim 1] A dicarboxylic acid or an ester-forming derivative thereof, ethylene glycol or butanediol in an amount of 30 to 94 mol% in the total diol component, and a diol having the structure shown in Formula 1 in an amount of 1 to 50 mol% in the total diol component. ,
5 polyoxyalkylene glycols out of all diol components
A thermoplastic polyester elastomer characterized by comprising ~50 mol%. [Formula 1] (wherein, R is an ethylene group, and X and Y are 2≦X+
It is an integer satisfying Y≦6. ) 2. The thermoplastic polyester elastomer according to claim 1, wherein the polyoxyalkylene glycol has a number average molecular weight of 300 to 20,000. 3. The thermoplastic polyester elastomer according to claim 1, wherein the diol having the structure represented by Chemical Formula 1 is an ethylene oxide adduct of bisphenol A.