JP2000007771A - Thermoplastic polyester elastomer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide thermoplastic polyester elastomers which broaden the field of their applications due to the rubber elasticity thereof and are excellent in low temperature properties. SOLUTION: Desired thermoplastic polyester elastomers comprise (A) an aromatic dicarboxylic acid component, (B) a short chain glycol component, and (C) a copolymerization polyether glycol component represented by the formula: HO- (R1-O)a-(R2-O)b-(R3-O)c}n-OH (wherein R1, R2 and R3 each is a 2-10C alkylene unit and R2 is different from both R1 and R3, and R1 may be the same as R3; a, b, and c each is an integer of 0 or more which satisfies a+b+c>=2, provided that at least two of a, b and c are 1 or more; and n is an integer of 2 or more and, at the same time, a number capable of attaining the molecular weight of component (C) of 500-4,000) which has a molecular weight of 500-4,000 and is composed of different two or more alkylene units and satisfy condition (D) that alkylene units having quaternary carbons in the total weight of the entire polyether glycol components of the polyester elastomers are less than 10 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermoplastic polyester elastomer. More specifically, a thermoplastic polyester elastomer with excellent low temperature properties, especially a novel thermoplastic polyester elastomer suitable for molding materials for automotive exterior parts (gears, boots, emblems, belts, tubes, etc.) and industrial products (packings, sheets, etc.) About.

[0002]

2. Description of the Related Art Conventionally, as a thermoplastic polyester elastomer, a polybutylene terephthalate (PBT) unit has been used as a hard segment and a polytetramethylene glycol (PBT) has been used.
TMG) as a soft segment, polyetherester elastomer (JP-B-49-48195, JP-B-49-31558), PBT
Polyester ester elastomer having a hard segment as a unit and a polycaprolactone (PCL) unit as a soft segment (JP-B-48-4116, JP-A-59-12926, JP-A-59-15117), and PBT unit And polyester ester elastomers having a dimer fatty acid as a soft segment and a dimer fatty acid as a soft segment (JP-A-54-127955).

[0003]

However, the above-mentioned conventional elastomer has a problem in that the rubber properties are deteriorated in a low temperature range, so that the flexibility cannot be maintained at room temperature. In the present invention, this disadvantage is solved,
To provide a thermoplastic polyester elastomer having a wide range of applications due to rubber elasticity and excellent in low-temperature properties.

[0004]

Means for Solving the Problems The present inventors have found that the above problems can be solved by using a specific soft segment, and have reached the present invention.

That is, the present invention is a thermoplastic polyester elastomer containing the following components A, B, and C, and satisfying the condition D. A. Aromatic dicarboxylic acid component B. Short chain glycol component C.I. The molecular weight represented by the following chemical formula 2 is 500 to 4000
And a copolymerized polyether glycol component comprising two or more different alkylene units. Chemical formula 2: HO-｛(R1 -O) a-(R2 -O) b-(R3-
O) c｝ n-H (1) R1, R2 and R3 are alkylene units having 2 to 10 carbon atoms, and R2 is different from any of R1 and R3;
R1 may be the same or different from R3. (2) a, b, and c are integers of 0 or more satisfying a + b + c ≧ 2 (at least two of a, b, and c are 1 or more) (3) n is an integer of 2 or more and the molecular weight of compound 1 50
Represents a number that can achieve 0-4000. Condition D: The alkylene unit having a quaternary carbon is less than 10% by weight in the total weight of all the polyether glycol components of the thermoplastic polyester elastomer.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. In the polyester of the present invention, the acid component is mainly composed of an aromatic dicarboxylic acid, but terephthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, isophthalic acid, one or a combination of two or more selected from 5-sodium sulfoisophthalic acid. Preferably, the aromatic dicarboxylic acid accounts for at least 70 mol%, preferably at least 80 mol% of the total acid component. As other acid components, alicyclic dicarboxylic acids and aliphatic dicarboxylic acids are used, and examples of the alicyclic dicarboxylic acids include cyclohexanedicarboxylic acid, tetrahydrophthalic anhydride and the like.
As aliphatic dicarboxylic acids, succinic acid, glutaric acid,
Adipic acid, azelaic acid, sebacic acid, dodecane diacid, dimer acid, hydrogenated dimer acid and the like can be mentioned. These are used in a range that does not significantly lower the melting point of the resin, and the amount thereof is less than 30 mol%, preferably less than 20 mol% of the total acid components.

Although the lower limit of the melting point is not particularly limited, it is generally preferably 150 ° C. or higher, particularly preferably 180 ° C. or higher.

[0008] The copolymer polyether glycol constituting the soft segment, that is, the long-chain polyester in the thermoplastic polyester elastomer of the present invention has a molecular weight of 5
And is represented by the following chemical formula 3. Chemical formula 3 HO-｛(R1 -O) a-(R2 -O) b-(R3-
O) c｝ n-H (1) R1, R2 and R3 are alkylene units having 2 to 10 carbon atoms, and R2 is different from any of R1 and R3;
R1 may be the same or different from R3. (2)
a, b, and c are integers of 0 or more satisfying a + b + c ≧ 2 (at least two of a, b, and c are 0 or more); (3) n is an integer of 2 or more and the molecular weight of compound 1 is 50
Represents a number that can achieve 0-4000. Further, n is preferably 4 or more, and most preferably 5 or more.

Further, the thermoplastic polyester elastomer of the present invention may contain a polyether glycol component other than the chemical formula 3, but an alkylene unit having a quaternary carbon in the total weight of all the polyether glycol components of the thermoplastic polyester elastomer. It must be less than 10% by weight, preferably less than 5% by weight, more preferably less than 3% by weight, and most preferably no quaternary carbon in the polyether glycol component. Polyester elastomers having quaternary carbon are inferior in weather resistance and gas permeability, and may deteriorate during use under severe conditions. The weight of the alkylene unit having a quaternary carbon in the weight of the polyether glycol component is calculated based on the alkylene oxide unit which is a raw material for producing the polyether glycol. That is, it is a unit of (RO) in the above chemical formula 3.

The copolymerized polyether glycol represented by the above formula 3 used in the thermoplastic polyester elastomer of the present invention is tetrahydrofuran (THF).
And a random copolymerized glycol obtained by ring-opening polymerization of ethylene oxide (EO). The content of the copolymerized polyether glycol represented by the above Chemical Formula 3 is preferably 5 to 95% by weight based on the whole polymer. More preferably,
Its content is from 15 to 80% by weight, even more preferably from 25 to 70% by weight. If the amount of the copolymerized polyether glycol is less than 5% by weight, phase separation tends to occur, and the elasticity is insufficient. On the other hand, if the content exceeds 95% by weight, the blockability of the obtained elastomer decreases, so that the melting point and softening point of the polymer decrease.

In the thermoplastic polyester elastomer of the present invention, the glycol components other than the copolymerized polyether glycol include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, and poly (tetramethylene oxide) glycol having a molecular weight of 400 to 6000. And polyalkylene ether glycols and mixtures thereof, and copolymerized polyether glycols obtained by copolymerizing these polyether glycol constituents, and aliphatic dicarboxylic acids having 2 to 12 carbon atoms and aliphatic glycols having 2 to 10 carbon atoms. Polyesters produced, for example, polyethylene adipate, polytetramethylene adipate, polyethylene sebacate, polyneopentyl sebacate, polytetramethylene dodecanoate,
Polytetramethylene azelate, polyhexamethylene azelate, poly-ε-caprolactone and the like. These glycols are used in an appropriate combination depending on the balance of various properties. The amount is 40-9 based on the acid component.
It is 9 mol%, preferably 50 to 95 mol%.

As the short-chain glycol component in the present invention, glycols having 1 to 25 carbon atoms and ester-forming derivatives thereof can be used. The glycol having 1 to 25 carbon atoms includes, for example, ethylene glycol, diethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-
Hexanediol, 1,9-nonanediol, neopentyl glycol, dimethylol heptane, dimethylol pentane, tricyclodecane dimethanol, ethylene oxide derivatives of bisphenol X (X is A, S, F) and their ester-forming derivatives Is mentioned. Preferably, ethylene glycol, 1,4-butanediol and their ester-forming derivatives are mentioned.

In the copolyester of the present invention,
It may contain a trifunctional or higher polycarboxylic acid or polyol component in a small amount. For example, trimellitic anhydride,
3 mol% of benzophenonetetracarboxylic acid, trimethylolpropane, glycerin, pyromellitic anhydride, etc.
The following can be used. The total amount of trifunctional or higher polycarboxylic acid and polyol components is 5 mol% or less, preferably 3 mol% or less, when the total of all polycarboxylic acid components and polyol components of the polyester is 100 mol%.

In the copolymerized polyester of the present invention, the reduced viscosity is desirably 0.5 to 4.0. Reduced viscosity
If it is less than 0.5, the mechanical properties are inferior, and if it exceeds 4.0, the fluidity is poor, so that the moldability is poor and the range of use as a molding material is limited.

In the production of the copolymerized polyester of the present invention,
Any known method can be applied. For example, melt polymerization method,
Any of a solution polymerization method, a solid phase polymerization method, and the like can be appropriately used.
In the case of a melt polymerization method, a transesterification method or a direct polymerization method may be used. It is, of course, desirable to carry out solid phase polymerization after melt polymerization in order to improve the viscosity of the resin.
After the polymerization of the polyester, the chain may be extended with an epoxy compound or the like.

As the catalyst used for the reaction, an antimony catalyst, a germanium catalyst and a titanium catalyst are preferred. In particular, titanium catalysts, more specifically, tetraalkyl titanates such as tetrabutyl titanate and tetramethyl titanate, and metal oxalates such as titanium potassium oxalate are preferable. The other catalyst is not particularly limited as long as it is a known catalyst, and examples thereof include tin compounds such as dibutyltin oxide and dibutyltin dilaurate, and lead compounds such as lead acetate.

The obtained polyester elastomer may contain known stabilizers (eg, heat stabilizers, light stabilizers, etc.). As a heat stabilizer, for example,
Phenol compounds such as 4,4-bis (2,6-di-tert-butylphenol), amine compounds such as N, N'-bis (β-naphthyl) -p-phenylenediamine, sulfur compounds such as dilaurylthionate Can be mentioned. Examples of the light stabilizer include substituted benzophenone and benzotriazole compounds. In addition to the stabilizer, a known resin, a low molecular compound, an inorganic substance, or the like may be blended, blended, or alloyed. For example, epoxy compounds, isocyanate compounds, pigments, reinforcing agents, additives and the like can be mentioned.

[0018]

The present invention will be described below in detail with reference to examples. In these examples, each measurement item followed the following method.

(1) Reduced viscosity 0.05 g of the polymer was dissolved in 25 ml of a mixed solvent (phenol / tetrachloroethane = 60/40) and measured at 30 ° C. using an Ostwald viscometer.

(2) Melting point and crystallization temperature The melting point was measured at a temperature of 20 ° C./min from room temperature using a DSC (differential scanning calorimeter) manufactured by Seiko Instruments Inc., and the peak temperature was measured. The crystallization temperature is from room temperature to 20 ° C / min.
The temperature was raised to a higher temperature by 2 ° C., melted and held at that temperature for 2 minutes, and then lowered at a rate of 10 ° C./min, and the peak temperature was taken as a measured value. The sample was placed in an aluminum pan and sealed with a lid.

(3) Surface hardness Measured according to ASTM D2240.

(4) A sample piece having a storage modulus of elasticity of 20 × 5 × 2 mm was placed on a rheovibron (DYNAMIC VISCOELAS
TOMETER) to -150 to 200 ° C 2 ° C /
Measured at a frequency of 110 Hz.

(5) Tensile strength, tensile elongation, 50% elongation stress Measured according to JIS K6251.

(6) Weather resistance JIS No. 3 dumbbell test pieces were punched out of a molded product having a thickness of 2 mm and subjected to a weather resistance test using a carbon arc two-light weatherometer. After the weathering treatment for 500 hours,
It was measured according to JIS K6251.

(7) Gas Permeability The gas permeability of oxygen was measured under a temperature condition of 30 ° C. using a double type C manufactured by Rika Seiki Kogyo Co., Ltd. The thickness of the test film was 100 μm.

Example 1 310.2 g of dimethyl terephthalate (DMT), 1,
239.3 g of 4-butanediol (BD), THF and E
O random copolymer (molecular weight 2000, THF / EO
= 70/30 (molar ratio)) 440.0 g, 1.60 g of Irganox-1330 (manufactured by Nippon Ciba Geigy), and 0.80 g of tetrabutyl titanate (TBT) were charged into a 4 L autoclave, and it was heated from room temperature to 220 ° C for 3 hours. Then, the temperature was raised to perform a transesterification reaction. Then, the pressure inside the can was gradually reduced and the temperature was further raised.
The initial condensation reaction was performed at a torr or lower. Further 250
The polymerization reaction was carried out at a temperature of 1 ° C. or lower at 2 ° C. for 2 hours, and the polymer was taken out in a pellet form. The reduced viscosity of the obtained polymer was 1.47. A predetermined test was performed on the obtained copolyester.

Example 2 319.4 g of dimethylnaphthalate (DMN), BD
192.3 g, random copolymer of THF and EO (molecular weight: 2,000, THF / EO = 70/30 (molar ratio))
440.0 g, 1.60 g of Irganox-1330, TB
0.80 g of T was charged into a 4 L autoclave, and the thermoplastic elastomer was polymerized. The reaction temperature was appropriately adjusted.

Comparative Example 1 310.2 g of DMT, 239.4 g of BD, PTMG
(Molecular weight 2000) 440.0 g, Irganox-133
1.60 g and 0.80 g of TBT were charged into a 4 L autoclave, and a thermoplastic elastomer was polymerized. The reaction temperature was appropriately adjusted.

Comparative Example 2 DMT 310.2 g, BD 219.5 g, PTMG
(Molecular weight 1000) 440.0 g, Irganox-133
1.60 g and 0.80 g of TBT were charged into a 4 L autoclave, and a thermoplastic elastomer was polymerized. The reaction temperature was appropriately adjusted.

Comparative Example 3 A copolymer composed of 310.2 g of DMT, 239.4 g of BD and THF and neopentylene oxide (NPO) (molecular weight: 2,000, THF / NPO = 70/30 (mo)
1 ratio)) 440.0 g, Irganox-1330 1.60
g and 0.80 g of TBT were charged into a 4 L autoclave to polymerize a thermoplastic elastomer. The reaction temperature was appropriately adjusted.

Table 1 shows the results of predetermined tests performed on Examples 1 and 2 and Comparative Examples 1, 2, and 3.

[0032]

[Table 1]

[0033]

As described above, the thermoplastic polyester elastomer of the present invention maintains flexibility even at low temperatures, and has a high crystal melting point and excellent thermal properties, so that it can be used at high temperatures. That is, from a low temperature around −30 to 12
It is an unprecedented polyester elastomer that maintains its properties as an elastomer at high temperatures around 0 ° C. Furthermore, since it has excellent weather resistance and low gas permeability, there is little deterioration in acid value over a long period of time, so that it can be widely used for various molding materials.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hitoshi Ueno 2-1-1 Katata, Otsu-shi, Shiga F-term in Toyobo Co., Ltd. Research Laboratory (reference) 4J029 AA03 AB04 AC02 AD01 AD06 AD10 AE01 BF25 BF27 CA02 CA04 CA05 CA06 CB05A CB06A CB10A CC05A CD03 CH06 EG09 FC03 FC05 FC35 FC36 HA01 HB01 HB03A JB171 JC751 JE182 JF321 JF361 JF371 JF381 JF471 KE02 KE03 KE05 KE09 KE12 KH01

Claims (1)

[Claims] 1. A thermoplastic polyester elastomer containing the following components A, B and C and satisfying the condition D: A. Aromatic dicarboxylic acid component B. Short chain glycol component C.I. The molecular weight represented by the following chemical formula 1 is 500 to 4000
And a copolymerized polyether glycol component comprising two or more different alkylene units. Chemical formula 1: HO-｛(R1 -O) a-(R2 -O) b-(R3-
O) c｝ n-H (1) R1, R2 and R3 are alkylene units having 2 to 10 carbon atoms, and R2 is different from any of R1 and R3;
R1 may be the same or different from R3. (2) a, b, and c are integers of 0 or more satisfying a + b + c ≧ 2 (at least two of a, b, and c are 1 or more); and (3) n is an integer of 2 or more, and Molecular weight 50
Represents a number that can achieve 0-4000. Condition D: 10 alkylene units having a quaternary carbon in the total weight of all polyether glycol components of the thermoplastic polyester elastomer
% By weight.