JP2022150988A - Thermoplastic polyester elastomer resin composition - Google Patents

Abstract

To provide a thermoplastic polyester elastomer composition having excellent acid resistance.SOLUTION: A thermoplastic polyester elastomer composition contains a resin component including a thermoplastic polyester elastomer A, and an inorganic filler B, wherein the thermoplastic polyester elastomer A is obtained by coupling a hard segment and a soft segment, the hard segment is composed of polyester including, as constituent components, an aromatic dicarboxylic acid, and aliphatic or alicyclic diol, wherein the soft segment includes aliphatic polycarbonate, the thermoplastic polyester elastomer resin composition contains 1 pts.mass or more and 40 pts.mass or less of the inorganic filler B with respect to 100 pts.mass of the resin component containing the thermoplastic polyester elastomer A, and an erosion depth of the thermoplastic polyester elastomer resin composition measured according to an acid resistance test method is 1.0 mm or less.SELECTED DRAWING: None

Description

The present invention relates to a thermoplastic polyester elastomer resin composition.

In JP-A-10-017657 (Patent Document 1), JP-A-2003-192778 (Patent Document 2), etc., crystalline polyesters such as polybutylene terephthalate (PBT) and polybutylene naphthalate (PBN) are used. Thermoplastic polyesters formed by bonding polyoxyalkylene glycols such as polytetramethylene glycol (PTMG) as hard segments and/or polyesters such as polycaprolactone (PCL) and polybutylene adipate (PBA) as soft segments. Elastomers are disclosed. The above thermoplastic polyester elastomer has been put into practical use.

However, polyester-polyether type elastomers using polyoxyalkylene glycols in the soft segment are known to be excellent in water resistance and low temperature properties, but poor in heat aging resistance. Polyester-polyester type elastomers using polyester for the soft segment are known to be excellent in heat aging resistance but inferior in water resistance and low-temperature properties.

For the purpose of solving these drawbacks, JP-B-07-039480 (Patent Document 3), JP-A-05-295049 (Patent Document 4), JP-A-06-306202 (Patent Document 5), In JP-A-10-182782 (Patent Document 6), JP-A-2001-206939 (Patent Document 7) and JP-A-2001-240663 (Patent Document 8), polyester using polycarbonate in the soft segment - Polycarbonate type elastomers are proposed. The above-described polyester-polycarbonate type elastomer is used in applications requiring high heat aging resistance, such as automotive engine peripheral parts, by taking advantage of its excellent characteristics.

JP-A-10-017657 Japanese Patent Application Laid-Open No. 2003-192778 Japanese Patent Publication No. 07-039480 JP-A-05-295049 JP-A-06-306202 JP-A-10-182782 JP-A-2001-206939 Japanese Patent Application Laid-Open No. 2001-240663

In the future automobile industry, the demand for on-board cables is expected to increase as electric vehicles take the place of conventional gasoline vehicles. The polyester-polycarbonate type elastomer described above is expected to be used as a material for next-generation automotive cables because of its high heat aging resistance and flexibility. However, conventional elastomers of this type have difficulty in passing the battery fluid (sulfuric acid) drop test, which is an essential item for the above applications.

In view of the above points, an object of the present invention is to provide a thermoplastic polyester elastomer resin composition having excellent acid resistance.

The present inventors have made extensive studies to provide a thermoplastic polyester elastomer resin composition having excellent acid resistance. As a result, the present inventors have surprisingly found that a thermoplastic polyester elastomer resin composition in which a specific inorganic filler is blended with a thermoplastic polyester elastomer has remarkably improved acid resistance, and have completed the present invention. The thermoplastic polyester elastomer resin composition also had excellent heat aging resistance.

That is, the present invention provides the following thermoplastic polyester elastomer resin composition.
[1] A thermoplastic polyester elastomer resin composition containing a resin component containing a thermoplastic polyester elastomer A and an inorganic filler B,
The thermoplastic polyester elastomer A is formed by combining hard segments and soft segments,
The hard segment is made of a polyester composed of an aromatic dicarboxylic acid and an aliphatic or alicyclic diol,
The soft segment comprises an aliphatic polycarbonate,
The thermoplastic polyester elastomer resin composition contains 1 part by mass or more and 40 parts by mass or less of the inorganic filler B with respect to 100 parts by mass of the resin component containing the thermoplastic polyester elastomer A,
A thermoplastic polyester elastomer resin composition, wherein the thermoplastic polyester elastomer resin composition has an erosion depth of 1.0 mm or less as measured according to the acid resistance test method.
[2] The resin component contains an olefinic elastomer C,
The thermoplastic polyester elastomer resin according to [1], wherein the resin component contains 10 parts by mass or more and 50 parts by mass or less of the olefin elastomer C with respect to the thermoplastic polyester elastomer A of 50 parts by mass or more and 90 parts by mass or less. Composition.
[3] The thermoplastic polyester elastomer resin composition according to [2], wherein the olefin elastomer C is a styrene elastomer.
[4] The resin component contains an epoxy group-containing polyolefin D,
[2] or [3], wherein the resin component contains 1 part by mass or more and 10 parts by mass or less of the epoxy group-containing polyolefin D with respect to a total of 100 parts by mass of the thermoplastic polyester elastomer A and the olefin elastomer C; A thermoplastic polyester elastomer resin composition as described.
[5] The thermoplastic polyester elastomer resin composition according to any one of [1] to [4], wherein the inorganic filler B has a pH of 9 or more and 11 or less.
[6] The hardness of the thermoplastic polyester elastomer resin composition measured according to the hardness test method for thermoplastics specified in ASTM D 2240 is D40 or more and D50 or less of [1] to [5]. The thermoplastic polyester elastomer resin composition according to any one of claims 1 to 3.
[7] The thermoplastic polyester elastomer A has a melting point of 150° C. or more and 225° C. or less,
Using a differential scanning calorimeter, the temperature is raised from room temperature to 300°C at a temperature increase rate of 20°C/min, held at 300°C for 3 minutes, and then cooled to room temperature at a temperature decrease rate of 100°C/min. Repeating the cycle three times. and the melting point (Tm3) of the thermoplastic polyester elastomer A measured at the third temperature drop in the operation. The thermoplastic polyester elastomer resin composition according to any one of [1] to [6], wherein the melting point difference (Tm1-Tm3) is from 0°C to 50°C.
[8] The thermoplastic polyester elastomer resin composition according to any one of [1] to [7], which is for extrusion molding.
[9] The thermoplastic polyester elastomer resin composition according to any one of [1] to [8], which is for cable coating.

According to the present invention, a thermoplastic polyester elastomer resin composition having excellent acid resistance can be provided.

Hereinafter, the thermoplastic polyester elastomer resin composition according to one embodiment (hereinafter also referred to as "this embodiment") of the present invention will be described in more detail. Here, in the present specification, the notation of the format "A to B" means the upper and lower limits of the range (that is, A to B or less), and when there is no unit description in A and only a unit is described in B , A and B are the same.

[Thermoplastic polyester elastomer resin composition]
The thermoplastic polyester elastomer resin composition according to this embodiment is a thermoplastic polyester elastomer resin composition containing a resin component containing a thermoplastic polyester elastomer A and an inorganic filler B. The above thermoplastic polyester elastomer A is formed by bonding hard segments and soft segments. The hard segment is made of a polyester composed of an aromatic dicarboxylic acid and an aliphatic or alicyclic diol. The soft segment comprises aliphatic polycarbonate. The thermoplastic polyester elastomer resin composition contains 1 part by mass or more and 40 parts by mass or less of the inorganic filler B with respect to 100 parts by mass of the resin component containing the thermoplastic polyester elastomer A. Furthermore, the depth of corrosion of the thermoplastic polyester elastomer resin composition measured according to the acid resistance test method is 1.0 mm or less. A thermoplastic polyester elastomer resin composition having such characteristics can have excellent acid resistance. The thermoplastic polyester elastomer resin composition can also have excellent heat aging resistance. Further, the thermoplastic polyester elastomer resin composition can have good outer diameter stability and surface smoothness in extrusion molding.

Therefore, the thermoplastic polyester elastomer resin composition according to the present embodiment is suitable for use as various molding materials such as fibers, films, and sheets. is preferably used as a molding material for The thermoplastic polyester elastomer resin composition is useful for applications requiring heat aging resistance, water resistance, low-temperature properties, acid resistance, etc., such as automobiles and home appliance parts, such as joint boots and wire coating materials. That is, the thermoplastic polyester elastomer resin composition is preferably for extrusion molding. It is also preferable that the thermoplastic polyester elastomer resin composition is used for cable coating.

In this specification, the "thermoplastic polyester elastomer resin composition" may be composed of a resin component containing a thermoplastic polyester elastomer A and an inorganic filler B. Further, the resin component may contain, in addition to the thermoplastic polyester elastomer A, an olefin elastomer C, an epoxy group-containing polyolefin D, and the like, as will be described later. Furthermore, the thermoplastic polyester elastomer resin composition may contain, in addition to the resin component containing the thermoplastic polyester elastomer A and the inorganic filler B, a cross-linking agent, an additive, and the like. In the present specification, the thermoplastic polyester elastomer resin composition in any of the above cases will be described with the same term "thermoplastic polyester elastomer resin composition".

The thermoplastic polyester elastomer resin composition according to the present embodiment can be evaluated as having excellent acid resistance due to the following properties. That is, when the depth of corrosion of the thermoplastic polyester elastomer resin composition measured according to the acid resistance test method is 1.0 mm or less, it can be evaluated as having excellent acid resistance. A method for measuring the depth of corrosion of the thermoplastic polyester elastomer resin composition using the acid resistance test method will be described below.

First, a 3 mm-thick plate-shaped molded product is obtained from the above thermoplastic polyester elastomer resin composition. Next, 0.1 μL of a 37% by mass sulfuric acid aqueous solution is dropped on the surface of the molded product, and then the molded product is heat-treated at 90° C. for 8 hours. Further, 0.1 μL of a 37% by mass sulfuric acid aqueous solution is added dropwise to the same spot on the surface of the molded product, and heat treatment is performed at 90° C. for 16 hours. Such an operation is regarded as one cycle, and a total of two cycles are performed. After that, the molded article is cut so as to include the eroded portion caused by dropping the sulfuric acid aqueous solution, and a cross section of the molded article is obtained. Finally, the depth of erosion of the thermoplastic polyester elastomer resin composition can be obtained by measuring the depth of erosion formed in the cross section of the molded product.

In this case, the erosion depth of the thermoplastic polyester elastomer resin composition is measured to be 1.0 mm or less. The erosion depth of the thermoplastic polyester elastomer resin composition is preferably 0.9 mm or less, more preferably 0.8 mm or less, and even more preferably 0.7 mm or less. If the erosion depth is 1.0 mm or less, it can be evaluated as having excellent acid resistance in the battery fluid (sulfuric acid) dropping test described above.

Furthermore, it is preferable that the thermoplastic polyester elastomer resin composition according to the present embodiment has excellent hardness due to the following properties. That is, the hardness of the thermoplastic polyester elastomer resin composition measured according to the hardness test method for thermoplastics specified in ASTM D 2240 is preferably D40 or more and D50 or less. In this embodiment, the hardness of the thermoplastic polyester elastomer resin composition can be obtained as follows according to the hardness test method for thermoplastics specified in ASTM D 2240.

First, the above thermoplastic polyester elastomer resin composition was injected from an injection molding machine with a cylinder temperature +20° C. of the melting point of the above resin composition and a mold temperature of 50° C. to obtain a length of 100 mm×width of 100 mm. An injection molded article with a thickness of 2.0 mm is obtained. Next, a predetermined needle tip is dropped in an environment of 23.degree. The hardness of the thermoplastic polyester elastomer resin composition can be obtained from the instantaneous Shore D value. The hardness means so-called surface hardness.

In this case, the hardness of the thermoplastic polyester elastomer resin composition is preferably D40 or more and D50 or less. The hardness of the thermoplastic polyester elastomer resin composition is more preferably D42 to D47, more preferably D43 to D46. When the hardness is D40 or more and D50 or less, the thermoplastic polyester elastomer resin composition can be particularly suitable for uses such as cable coating. If the hardness exceeds D50, the flexibility of the thermoplastic polyester elastomer resin composition may be insufficient. If the hardness is less than D40, the thermoplastic polyester elastomer resin composition becomes excessively soft, which may make it impossible to ensure the strength of the molded article.

<Thermoplastic polyester elastomer A>
The thermoplastic polyester elastomer resin composition according to this embodiment contains the resin component containing the thermoplastic polyester elastomer A and the inorganic filler B as described above. The above thermoplastic polyester elastomer A is formed by bonding hard segments and soft segments. The hard segment is made of a polyester composed of an aromatic dicarboxylic acid and an aliphatic or alicyclic diol. The soft segment comprises aliphatic polycarbonate. In this specification, the hard segment and the soft segment are "combined" means a state in which the hard segment and the soft segment are combined with a chain extender such as an isocyanate compound, and a configuration that constitutes the hard segment and the soft segment. It means both states in which the units are directly linked via an ester bond and/or a carbonate bond. Among these, it is preferable that the hard segment and the soft segment are in a state in which the structural units constituting the hard segment and the soft segment are directly bonded via an ester bond and/or a carbonate bond.

(hard segment)
The hard segment consists of a polyester composed of an aromatic dicarboxylic acid and an aliphatic or alicyclic diol as described above. Conventionally known aromatic dicarboxylic acids can be widely used as the aromatic dicarboxylic acid that constitutes the polyester of the hard segment, and is not particularly limited. Preferred examples of the aromatic dicarboxylic acid include terephthalic acid and naphthalenedicarboxylic acid (among the isomers, 2,6-naphthalenedicarboxylic acid is preferred). The content of these aromatic dicarboxylic acids is preferably 70 mol % or more, more preferably 80 mol % or more, of the total dicarboxylic acids constituting the hard segment polyester. Other dicarboxylic acids include aromatic dicarboxylic acids such as diphenyldicarboxylic acid, isophthalic acid, and 5-sodium sulfoisophthalic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid and tetrahydrophthalic anhydride, succinic acid, glutaric acid, and adipine. Acids, aliphatic dicarboxylic acids such as azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, hydrogenated dimer acid, and the like can be included. These dicarboxylic acids can be used within a range that does not significantly lower the melting point of the thermoplastic polyester elastomer A. It is more preferable to have

As the aliphatic or alicyclic diol constituting the polyester of the hard segment, conventionally known aliphatic or alicyclic diols can be widely used without particular limitation. The above aliphatic or alicyclic diols are preferably alkylene glycols having 2 to 8 carbon atoms. Specific examples include ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, and 1,4-cyclohexanedimethanol. Among these, either ethylene glycol or 1,4-butanediol is preferred.

As the component constituting the polyester of the hard segment, a structural unit derived from butylene terephthalate (a structural unit derived from terephthalic acid and 1,4-butanediol), or a structural unit derived from butylene naphthalate (2,6- A component composed of structural units derived from naphthalenedicarboxylic acid and 1,4-butanediol) is preferable from the viewpoint of physical properties, moldability and cost performance.

The above-mentioned thermoplastic polyester elastomer A can be prepared by previously producing an aromatic polyester suitable as the polyester constituting the hard segment, and then copolymerizing it with the soft segment component described below. In this case, the above aromatic polyester can be easily obtained according to a normal polyester production method. The polyester constituting the hard segment preferably has a number average molecular weight of 10,000 to 40,000.

(soft segment)
The soft segment comprises an aliphatic polycarbonate as described above. The aliphatic polycarbonate preferably contains structural units mainly derived from aliphatic diols having 2 to 12 carbon atoms. Examples of these aliphatic diols include ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 2,2 -dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,9-nonanediol, 2-methyl-1,8-octane A diol etc. can be illustrated. In particular, from the viewpoint of imparting flexibility and low-temperature properties to the thermoplastic polyester elastomer A, the aliphatic polycarbonate preferably contains a structural unit derived from an aliphatic diol having 5 to 12 carbon atoms. These components may be used singly or in combination of two or more, as required, based on the examples described below.

As the aliphatic polycarbonate diol, which is a raw material for the aliphatic polycarbonate, those having a low melting point (for example, 70° C. or lower) and a low glass transition temperature are preferred. For example, an aliphatic polycarbonate diol composed of structural units derived from 1,6-hexanediol has a low glass transition temperature of around -60°C and a melting point of around 50°C, and is therefore preferable because it has good low-temperature properties. Further, an aliphatic polycarbonate diol obtained by copolymerizing an appropriate amount of 3-methyl-1,5-pentanediol with the above aliphatic polycarbonate diol has a slightly higher glass transition point than the aliphatic polycarbonate diol before copolymerization. However, it is preferable because the melting point is lowered or becomes amorphous, and the low-temperature characteristics are improved. Furthermore, for example, an aliphatic polycarbonate diol composed of 1,9-nonanediol and 2-methyl-1,8-octanediol has a melting point of about 30°C and a glass transition temperature of about -70°C, which are sufficiently low. is particularly good, so it is preferable.

The above-mentioned aliphatic polycarbonate should not necessarily be limited to being composed only of a polycarbonate component, and may be copolymerized with a small amount of other glycol, dicarboxylic acid, ester compound, ether compound, or the like. Examples of such copolymer components include, for example, glycols such as dimer diol, hydrogenated dimer diol and modified products thereof; dicarboxylic acids such as dimer acid and hydrogenated dimer acid; Examples include polyesters or oligoesters composed of dicarboxylic acid and glycol, polyesters or oligoesters composed of ε-caprolactone, polyalkylene glycols such as polytetramethylene glycol and polyoxyethylene glycol, or oligoalkylene glycols. On the other hand, it is also preferred that the soft segment consists of an aliphatic polycarbonate.

The copolymerization component can be contained to such an extent that the effect of the aliphatic polycarbonate segment is not substantially lost. In the thermoplastic polyester elastomer A, the mass ratio of the hard segment to the soft segment is preferably hard segment:soft segment=30:70 to 95:5, more preferably 40:60 to 90:10, More preferably 45:55 to 90:10, most preferably 50:50 to 90:10.

Generally, in the thermoplastic polyester elastomer A, the higher the hard segment ratio, the better the heat aging resistance and acid resistance. On the other hand, the higher the hard segment ratio, the higher the hardness, which tends to impair flexibility and low-temperature properties. Therefore, in the thermoplastic polyester elastomer A, the mass ratio of the hard segment to the soft segment is preferably within the range described above.

Thermoplastic polyester elastomer A can be produced by a known method. For example, a method of obtaining a reaction product by subjecting a lower alcohol diester of a dicarboxylic acid, an excessive amount of a low molecular weight glycol, and a soft segment component to a transesterification reaction in the presence of a catalyst, and polycondensing the reaction product; A method of obtaining a reaction product by subjecting an excessive amount of glycol and a soft segment component to an esterification reaction in the presence of a catalyst, and polycondensing the reaction product; A method of adding components and randomizing by transesterification, a method of linking the hard segment and the soft segment with a chain linking agent, and ε-caprolactone in the hard segment when poly(ε-caprolactone) is used for the soft segment The thermoplastic polyester elastomer A can be produced by selecting an appropriate method from methods such as addition reaction of monomers.

Here, the thermoplastic polyester elastomer A preferably has a melting point of 150°C or higher and 225°C or lower. In this case, using a differential scanning calorimeter, the temperature is raised from room temperature to 300 ° C. at a temperature increase rate of 20 ° C./min, held at 300 ° C. for 3 minutes, and then cooled to room temperature at a temperature decrease rate of 100 ° C./min. The melting point (Tm1) of the thermoplastic polyester elastomer A measured at the first temperature drop in the operation repeated three times, and the melting point (Tm1) of the thermoplastic polyester elastomer A measured at the third temperature drop in the operation ( The melting point difference (Tm1-Tm3) from Tm3) is preferably 0° C. or more and 50° C. or less. The above-mentioned thermoplastic polyester elastomer resin composition can exhibit the effects of the present embodiment with good yield by containing the thermoplastic polyester elastomer A having the above-mentioned melting point characteristics.

The melting point difference (Tm1-Tm3) is more preferably 0 to 40.degree. C., even more preferably 0 to 30.degree. The melting point difference is a measure of the ability of the thermoplastic polyester elastomer A to retain its blocking properties. The thermoplastic polyester elastomer A can be evaluated to have excellent blocking ability as the melting point difference decreases. When the melting point difference of the thermoplastic polyester elastomer A is 0° C. or higher and 50° C. or lower, it is possible to obtain a molded product with excellent uniformity in quality due to the excellent ability to retain block property. If the melting point difference exceeds 50° C., the ability to retain the blocking property is deteriorated, and quality fluctuations during molding processing become large, so there is a risk that the uniformity of quality and recyclability of the molded product will deteriorate.

Furthermore, the melting point of the thermoplastic polyester elastomer A is more preferably 190-220°C. If the melting point is less than 150°C, the thermoplastic polyester elastomer A will melt at high temperatures, which may limit its use in high-temperature environments. If the melting point exceeds 225°C, the molding temperature becomes excessively high, so that the soft segment tends to decompose during molding, and it may be difficult to obtain the desired heat aging resistance.

The melting point (Tm) of thermoplastic polyester elastomer A can be obtained by the following method. That is, the thermoplastic polyester elastomer A dried under reduced pressure at 50° C. for 15 hours was measured using a differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corporation) at a temperature elevation rate of 20° C./min from room temperature. The melting point (Tm) of the thermoplastic polyester elastomer A can be determined as the temperature at which the endothermic peak occurs. A sample for measuring the melting point of the thermoplastic polyester elastomer A was prepared by weighing 10 mg in an aluminum pan (manufactured by TA Instruments, product number 900793.901), and an aluminum lid (manufactured by TA Instruments , part number 900794.901). Also, the melting point is measured in an argon atmosphere.

Furthermore, the melting point difference (Tm1-Tm3) of the thermoplastic polyester elastomer A can be obtained by the following method. First, 10 mg of thermoplastic polyester elastomer A dried under reduced pressure at 50° C. for 15 hours was weighed in an aluminum pan (manufactured by TA Instruments, product number 900793.901), and an aluminum lid (manufactured by TA Instruments, product number 900794.901) was weighed. A sample for measurement is prepared by sealing with Next, using a differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corporation), the aluminum pan in which the measurement sample was sealed was heated from room temperature to 300 ° C. at a temperature increase rate of 20 ° C./min under a nitrogen atmosphere. and held at 300°C for 3 minutes. Thereafter, the aluminum pan is immersed in liquid nitrogen and rapidly cooled to lower the temperature to room temperature at a temperature lowering rate of 100° C./min. Subsequently, after standing at room temperature for 30 minutes, the differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corporation) is again used to raise the temperature from room temperature to 300° C. at a heating rate of 20° C./min. This cycle is repeated three times, and the melting point (Tm1) of the measurement sample (thermoplastic polyester elastomer A) is measured when the temperature is lowered to room temperature for the first time, and the above measurement is measured when the temperature is lowered to room temperature for the third time. The melting point difference (Tm1-Tm3) can be determined by measuring the melting point (Tm3) of the sample (thermoplastic polyester elastomer A).

<Inorganic filler B>
The thermoplastic polyester elastomer resin composition according to this embodiment contains the resin component containing the thermoplastic polyester elastomer A and the inorganic filler B as described above. The thermoplastic polyester elastomer resin composition contains 1 part by mass or more and 40 parts by mass or less of the inorganic filler B with respect to 100 parts by mass of the resin component containing the thermoplastic polyester elastomer A. Thereby, the thermoplastic polyester elastomer resin composition can be remarkably improved in acid resistance.

The inorganic filler B is added for the purpose of developing acid resistance in the thermoplastic polyester elastomer resin composition. As the inorganic filler B, conventionally known inorganic fillers may be used without particular limitation, as long as they do not impair the physical properties of the thermoplastic polyester elastomer resin composition and exhibit the effects of the present embodiment to exhibit acid resistance. be able to. Examples of the inorganic filler B include metals such as aluminum, copper, and nickel, oxides such as alumina, magnesium oxide, beryllium oxide, chromium oxide, and titanium oxide, calcium carbonate, boron nitride, aluminum nitride, silicon nitride, titanium nitride, Nitrides such as tantalum nitride and chromium nitride, borides such as titanium boride, zirconium boride, hafnium boride, yttrium boride, vanadium boride, magnesium diboride, niobium boride, tantalum boride, and thallium boride , boron carbide, titanium carbide, zirconium carbide, vanadium carbide, niobium carbide, tantalum carbide, chromium carbide, molybdenum carbide, tungsten carbide, tungsten carbide II, carbides such as silicon carbide, Fe—Si alloy, Fe—Al alloy, Fe— Si—Al alloy, Fe—Si—Cr alloy, Fe—Ni alloy, Fe—Ni—Co alloy, Fe—Ni—Mo alloy, Fe—Co alloy, Fe—Si—Al—Cr alloy, Fe—Si—B Alloys such as Fe-Si-Co-B alloy Mn-Zn ferrite, Mn-Mg-Zn ferrite, Mg-Cu-Zn ferrite, Ni-Zn ferrite, Ni-Cu-Zn ferrite, Cu-Zn ferrite, etc. can be exemplified. These inorganic fillers may be used individually by 1 type, and may use 2 or more types together.

The thermoplastic polyester elastomer resin composition contains 1 part by mass or more and 40 parts by mass or less of the inorganic filler B with respect to 100 parts by mass of the resin component containing the thermoplastic polyester elastomer A as described above. The thermoplastic polyester elastomer resin composition preferably contains 5 to 35% by mass, more preferably 10 to 35% by mass of the inorganic filler B with respect to 100 parts by mass of the resin component containing the thermoplastic polyester elastomer A, Most preferably, it contains 10 to 30% by mass. If the content of the inorganic filler B is less than 1% by mass with respect to 100 parts by mass of the resin component containing the thermoplastic polyester elastomer A, it becomes difficult to obtain the desired acid resistance. If the content of the inorganic filler B exceeds 40% by mass with respect to 100 parts by mass of the resin component containing the thermoplastic polyester elastomer A, the hardness becomes excessively high, making it difficult to obtain the desired heat aging resistance. becomes.

The inorganic filler B preferably has a pH of 9 or more and 11 or less. In this case, the thermoplastic polyester elastomer resin composition can be particularly excellent in acid resistance. The pH of the inorganic filler B is more preferably pH 9.2-11, and most preferably pH 9.5-11. If the inorganic filler B has a pH of less than 9.0, it may be difficult to obtain preferable acid resistance. If the pH of the inorganic filler B exceeds 11, the physical properties of the thermoplastic polyester elastomer resin composition itself may be deteriorated. Examples of preferable inorganic filler B include calcium carbonate and wollastonite.

<Olefin Elastomer C>
The thermoplastic polyester elastomer resin composition according to this embodiment contains the resin component containing the thermoplastic polyester elastomer A and the inorganic filler B as described above. The resin component preferably contains an olefinic elastomer C. In this case, by including the olefinic elastomer C, it is possible to impart acid resistance to the nonpolar resin, so that the acid resistance of the thermoplastic polyester elastomer resin composition can be improved. The resin component preferably contains 10 parts by mass or more and 50 parts by mass or less of the olefin elastomer C with respect to the thermoplastic polyester elastomer A of 50 parts by mass or more and 90 parts by mass or less.

The olefinic elastomer C may be an unmodified olefinic elastomer or a modified olefinic elastomer. For example, if the olefinic elastomer C is a modified olefinic elastomer, the modified ethylene/α- An olefinic copolymer is preferred.

The ethylene/α-olefin copolymer means a copolymer composed of ethylene and at least one α-olefin having 3 to 20 carbon atoms. Specific examples of at least one α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene and 1-decene. , 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3 -methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene , 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene and combinations thereof. . Among these α-olefins, α-olefins having 4 to 12 carbon atoms are preferred.

Modification of the olefinic elastomer is preferably acid modification performed with an unsaturated carboxylic acid or a derivative thereof. Specific examples of unsaturated carboxylic acids or derivatives thereof include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, methylmaleic acid, methylfumaric acid, citraconic acid, glutaconic acid, and metal salts of these carboxylic acids. , methyl hydrogen maleate, methyl hydrogen itaconate, methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, diethyl maleate, dimethyl itaconate, maleic anhydride, anhydrous Examples include itaconic acid, citraconic anhydride, maleimide, N-ethylmaleimide, N-butylmaleimide, N-phenylmaleimide, glycidyl acrylate, glycidyl methacrylate, glycidyl itaconate, and glycidyl citraconate. Among the modified olefin elastomers, the olefin elastomer C is composed of ethylene obtained by modifying with an unsaturated carboxylic acid and/or its acid anhydride and an α-olefin having 4 to 12 carbon atoms. It is preferably a copolymer with

The olefin elastomer C is preferably a styrene elastomer. The styrene-based elastomer can be a hydrogenated modified styrene-conjugated diene block copolymer (hereinafter also referred to as "hydrogenated styrene-conjugated diene block copolymer"). A styrene-conjugated diene block copolymer is a block copolymer consisting of a styrene block and a diene block. Including coalescence. A butadiene block, an isoprene block, etc. can be illustrated as a component of the said diene block copolymer.

A specific example of the hydrogenated styrene-conjugated diene block copolymer is hydrogenated styrene-ethylene-butylene-styrene block copolymer (SEBS), which is a hydrogenated product of styrene-butadiene-styrene block copolymer (SBS). , hydrogenated styrene-ethylene-propylene-styrene block copolymer (SEPS), which is a hydrogenated product of styrene-isoprene-styrene block copolymer (SIS), styrene-butadiene/isoprene-styrene block copolymer (SBIS) Hydrogenated styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS), which is a hydrogenated product of, can be exemplified. When the olefinic elastomer C is a modified hydrogenated styrene elastomer, its number average molecular weight is preferably 30,000 to 80,000, more preferably 40,000 to 60,000.

When the olefinic elastomer C is unmodified, the reaction with the acid terminal blocking agent can be suppressed, which is preferable. When the acid-modified olefinic elastomer C is blended, the reaction between the acid end-blocking agent and the acid-modified portion of the olefinic elastomer C or the reaction between the acid end-blocking agent and the acid end of the thermoplastic polyester elastomer A is complex. This is because there is a possibility that the viscosity may increase and gelation may occur, and the appearance of the extruded product may deteriorate.

When the thermoplastic polyester elastomer resin composition according to the present embodiment contains the olefin elastomer C as the resin component, the resin component is added to the thermoplastic polyester elastomer A of 50 parts by mass or more and 90 parts by mass or less. It is preferable that 10 parts by mass or more and 50 parts by mass or less of the olefinic elastomer C is included. That is, when the total of the thermoplastic polyester elastomer A and the olefin elastomer C is 100 parts by mass, the mass ratio (A/C) of the thermoplastic polyester elastomer A and the olefin elastomer C is 90/10 to 50/50. Preferably. The mass ratio (A/C) is more preferably 80/20 to 65/45, even more preferably 70/30 to 60/40. If the amount of the olefinic elastomer C added is less than 10 parts by mass, the acid resistance may be insufficient. is likely to be sufficient.

Here, in the thermoplastic polyester elastomer resin composition according to the present embodiment, if flexibility is not particularly required, the same olefinic resin as the olefinic elastomer C can be used instead of the olefinic elastomer C to achieve the same effect. You may use it in the compounding quantity of the range. In this case, polyethylene, polypropylene, ethylene tetrafluoroethylene and the like can be exemplified as the olefin resin.

<Epoxy group-containing polyolefin D>
The thermoplastic polyester elastomer resin composition according to this embodiment contains the resin component containing the thermoplastic polyester elastomer A and the inorganic filler B as described above. In addition to the olefin-based elastomer C, the resin component preferably contains an epoxy group-containing polyolefin D. In this case, by including the epoxy group-containing polyolefin D, the thermoplastic polyester elastomer A and the olefin-based elastomer C are made compatibilized, thereby suppressing the occurrence of pulsation and the like during extrusion molding of the resin composition. The resin component preferably contains 1 part by mass or more and 10 parts by mass or less of the epoxy group-containing polyolefin D with respect to a total of 100 parts by mass of the thermoplastic polyester elastomer A and the olefin elastomer C. The olefinic elastomer C and the epoxy group-containing polyolefin D can be distinguished by whether or not the molecule contains an epoxy group (or whether or not the molecule is epoxy-modified).

The epoxy group-containing polyolefin D means an epoxy-modified polyolefin resin, and preferably has an epoxy value of 0.01 to 0.5 meq/g. The epoxy group-containing polyolefin D reacts with the terminal groups of the thermoplastic polyester elastomer A, thereby compatibilizing the thermoplastic polyester elastomer A and the olefin elastomer C when the olefin elastomer C is unmodified. can act as an agent. Further, the epoxy group-containing polyolefin D can contribute to stabilization of the melt viscosity of the resin composition during melt retention due to its appropriate epoxy value. The epoxy value of the epoxy group-containing polyolefin D is preferably 0.05 to 0.45 meq/g, more preferably 0.1 to 0.3 meq/g. If the epoxy value is less than 0.01 meq/g, the compatibility between the thermoplastic polyester elastomer A and the olefinic elastomer C is lowered, which may cause pulsation during extrusion molding. If the epoxy value exceeds 0.5 meq/g, the melt viscosity increases during heat retention, and they themselves may gradually become coarse cross-linking points, causing gelation.

The epoxy group-containing polyolefin D is preferably an epoxy group-containing polyolefin copolymer. The epoxy group-containing polyolefin copolymer is preferably, for example, a terpolymer composed of an α-olefin, an unsaturated compound other than the α-olefin, and a glycidyl ester of an α,β-unsaturated acid. Examples of the α-olefin include ethylene, propylene, butene-1, etc. Among them, ethylene is preferably used. Examples of unsaturated compounds other than α-olefins include vinyl ethers, vinyl esters such as vinyl acetate and vinyl propionate, esters of acrylic acid and methacrylic acid such as methyl, ethyl, propyl and butyl, acrylonitrile and styrene. Among them, butyl acrylate, methyl acrylate or methyl methacrylate is preferably used. Examples of glycidyl esters of α,β-unsaturated acids include glycidyl acrylate, glycidyl methacrylate and glycidyl ethacrylate, with glycidyl methacrylate being preferred.

When the thermoplastic polyester elastomer resin composition according to the present embodiment contains the epoxy group-containing polyolefin D as the resin component in addition to the olefin elastomer C, the resin component is the thermoplastic polyester elastomer A as described above. The epoxy group-containing polyolefin D preferably contains 1 to 10 parts by mass, more preferably 1 to 9 parts by mass, and still more preferably 2 to 8 parts by mass, based on a total of 100 parts by mass including the olefin elastomer C. parts, most preferably 3 to 7 parts by weight. If less than 0.1 part by mass of the epoxy group-containing polyolefin D is included with respect to a total of 100 parts by mass of the thermoplastic polyester elastomer A and the olefin elastomer C, the effect as a compatibilizer may be insufficient. . When the epoxy group-containing polyolefin D is contained in an amount exceeding 10 parts by mass with respect to a total of 100 parts by mass of the thermoplastic polyester elastomer A and the olefin elastomer C, the acid terminal of the thermoplastic polyester elastomer A and the epoxy group are formed during retention. may react and cause gelation.

<Other ingredients>
The thermoplastic polyester elastomer resin composition according to the present embodiment can be blended with various additives as necessary within a range that does not impair the effects of the present embodiment.

If necessary, the thermoplastic polyester elastomer resin composition may be blended with general-purpose antioxidants such as aromatic amine-based, hindered phenol-based, phosphorus-based, and sulfur-based antioxidants.

When the thermoplastic polyester elastomer resin composition requires weather resistance, it is preferable to add an ultraviolet absorber and/or a hindered amine compound (hereinafter also collectively referred to as "light stabilizer"). For example, benzophenone-based, benzotriazole-based, triazole-based, nickel-based, and salicyl-based light stabilizers can be used. Specifically, 2,2′-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, pt-butylphenyl salicylate, 2,4-di-t-butylphenyl-3, 5-di-t-butyl-4-hydroxybenzoate, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t-amyl- phenyl)benzotriazole, 2-[2'-hydroxy-3',5'-bis(α,α-dimethylbenzylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'- methylphenyl)-5-chlorobenztriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzothiriazole, 2,5-bis-[5'- t-butylbenzoxazolyl-(2)]-thiophene, bis(3,5-di-t-butyl-4-hydroxybenzyl phosphate monoethyl ester) nickel salt, 2-ethoxy-5-t-butyl-2 a mixture of 85-90% '-ethyl oxalic acid-bis-anilide and 10-15% 2-ethoxy-5-t-butyl-2'-ethyl-4'-t-butyl oxalic acid-bis-anilide; 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, 2-ethoxy-2′-ethyloxazalic acid bisanilide, 2-[2′-hydroxy -5'-methyl-3'-(3'',4'',5'',6''-tetrahydrophthalimido-methyl)phenyl]benzotriazole, bis(5-benzoyl-4-hydroxy-2-methoxyphenyl ) methane, 2-(2′-hydroxy-5′-t-octylphenyl)benzotriazole, 2-hydroxy-4-i-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2-hydroxy-4- Light stabilizers such as octadecyloxybenzophenone and phenyl salicylate can be exemplified. When an ultraviolet absorber and/or a hindered amine compound is added to the thermoplastic polyester elastomer resin composition, the content thereof is 0.1 parts by mass or more and 5 parts by mass with respect to 100 parts by mass of the thermoplastic polyester elastomer resin composition. The following are preferable.

The thermoplastic polyester elastomer resin composition according to the present embodiment can be blended with various other additives. As additives, a resin other than the thermoplastic polyester elastomer, a thickener, a terminal blocking agent, a stabilizer, and an antiaging agent can be added within a range that does not impair the effects of the present embodiment. As other additives, coloring pigments, inorganic and organic fillers, coupling agents, tackiness improvers, quenchers, stabilizers such as metal deactivators, and flame retardants can be added. The amount of various additives to be added can be appropriately selected within a range that does not impair the effects of the present embodiment, and the amount of addition used in molding of ordinary thermoplastic resins can be employed. On the other hand, the thermoplastic polyester elastomer resin composition according to the present embodiment is the total of the thermoplastic polyester elastomer A, the inorganic filler B, the olefin elastomer C and the epoxy group-containing polyolefin D (however, the olefin elastomer C and the epoxy group-containing polyolefin D is an optional component) accounts for preferably 75% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more.

As a method for determining the composition and composition ratio of the thermoplastic polyester elastomer resin composition according to the present embodiment, for example, a sample is dissolved in a solvent such as deuterated chloroform and measured, and then calculated from the proton integral ratio of ¹ H-NMR. be able to.

<Effect>
The thermoplastic polyester elastomer resin composition according to this embodiment has excellent acid resistance and heat aging resistance. Furthermore, it is possible to retain the flexibility, moldability, chemical resistance, bending fatigue resistance, abrasion resistance, electrical properties and other properties inherent in the thermoplastic polyester elastomer. Therefore, the above thermoplastic polyester elastomer resin composition can be applied to a wide range of parts such as various parts of electric appliances, hoses, tubes and cable covering materials. In particular, it is suitable for use as a cable covering material. The thermoplastic polyester elastomer resin composition can be molded into various shapes by injection molding, transfer molding, blow molding, etc., in addition to extrusion molding.

[Method for producing thermoplastic polyester elastomer resin composition]
As long as the thermoplastic polyester elastomer resin composition according to the present embodiment contains the specific thermoplastic polyester elastomer A and the specific inorganic filler B in the ratio described above, this type of thermoplastic polyester elastomer resin composition can be produced. It can be obtained by applying a conventionally known manufacturing method. For example, the thermoplastic polyester elastomer resin composition according to this embodiment can be obtained by the following production method.

As the manufacturing method, first, a thermoplastic polyester elastomer A and an inorganic filler B for constituting the thermoplastic polyester elastomer resin composition are prepared. The thermoplastic polyester elastomer A is obtained by, for example, transesterifying a lower alcohol diester of a dicarboxylic acid, an excessive amount of a low molecular weight glycol, and a soft segment component (aliphatic polycarbonate diol) in the presence of a catalyst to obtain a reaction product. A method of polycondensing the reaction product, a method of obtaining a reaction product by esterifying a dicarboxylic acid, an excess amount of glycol and a soft segment component in the presence of a catalyst, and polycondensing the reaction product. A method of preparing a hard segment polyester, adding a soft segment component to the polyester, randomizing it by transesterification, a method of connecting the hard segment and the soft segment with a chain linking agent, and poly (ε-caprolactone) When it is used for the soft segment, it can be prepared by selecting an appropriate method from methods such as addition reaction of ε-caprolactone monomer to the hard segment. In this case, other additives such as the olefinic elastomer C and the epoxy group-containing polyolefin D can be added during the transesterification reaction or the addition reaction. Alternatively, for resin components such as olefin elastomer C and epoxy group-containing polyolefin D, the timing of producing a thermoplastic polyester elastomer resin composition from thermoplastic polyester elastomer A and inorganic filler B using a co-rotating twin-screw extruder or the like. and can also be added to the co-rotating twin-screw extruder.

Inorganic filler B can be prepared by obtaining a commercially available inorganic filler.

The thermoplastic polyester elastomer resin composition is prepared, for example, by charging the thermoplastic polyester elastomer A, the inorganic filler B, and, if necessary, the olefinic elastomer C and the epoxy group-containing polyolefin D into a co-rotating twin-screw extruder or the like. can be obtained by kneading and then pelletizing.

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples. Each measured value described in the examples was measured by the following measuring method.

<Hardness (surface hardness, Shore D)>
The surface hardness of the thermoplastic polyester elastomer resin composition of each example and comparative example was measured in a 23° C. environment according to the test method (Shore D) described in ASTM D 2240 as follows.

First, the above thermoplastic polyester elastomer resin composition was injected from an injection molding machine with a cylinder temperature +20° C. of the melting point of the above resin composition and a mold temperature of 50° C. to obtain a length of 100 mm×width of 100 mm. An injection molded product with a thickness of 2.0 mm was obtained. Next, a predetermined needle tip was dropped in an environment of 23.degree. The instantaneous Shore D value was defined as the hardness (surface hardness) of the resin composition.

<Measurement of acid resistance (dripping at 90°C), that is, corrosion depth>
In order to measure the corrosion depth of the thermoplastic polyester elastomer resin composition of each example and comparative example, an acid resistance test was conducted as follows.

First, a flat plate-shaped molded article having a thickness of 3 mm was obtained from the above thermoplastic polyester elastomer resin composition. Next, 0.1 μL of a 37% by mass sulfuric acid aqueous solution was dropped on the surface of the molded product, and then the molded product was heat-treated at 90° C. for 8 hours. Further, 0.1 μL of a 37% by mass sulfuric acid aqueous solution was added dropwise to the same portion of the surface of the molded product, and heat treatment was subsequently performed at 90° C. for 16 hours. A total of two cycles of such operations were performed as one cycle, and then the molded product was cut so as to include the eroded portion caused by dropping the sulfuric acid aqueous solution to obtain a cross section of the molded product. Finally, the depth (unit: mm) of the erosion formed in the cross section of the molded article was measured. If the erosion depth is as low as 1.0 mm or less, the thermoplastic polyester elastomer resin composition can be evaluated as having excellent acid resistance.

<Melting point (Tm) and melting point difference (Tm1-Tm3)>
The melting point (Tm) of the thermoplastic polyester elastomer A in each example and comparative example was obtained by the following method. That is, the thermoplastic polyester elastomer A dried under reduced pressure at 50° C. for 15 hours was measured using a differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corporation) at a temperature elevation rate of 20° C./min from room temperature. The melting point (Tm) of the thermoplastic polyester elastomer A was determined as the temperature at which the endothermic peak occurred. Here, a sample for measuring the melting point of the thermoplastic polyester elastomer A was prepared by weighing 10 mg in an aluminum pan (manufactured by TA Instruments, product number 900793.901), followed by an aluminum lid (manufactured by TA Instruments). , Part No. 900794.901) was used to make a sealed state. Moreover, the above melting points were measured in an argon atmosphere.

Further, the melting point difference (Tm1-Tm3) of thermoplastic polyester elastomer A was determined by the following method. First, 10 mg of thermoplastic polyester elastomer A dried under reduced pressure at 50° C. for 15 hours was weighed in an aluminum pan (manufactured by TA Instruments, product number 900793.901), and an aluminum lid (manufactured by TA Instruments, product number 900794.901) was weighed. A sample for measurement was prepared by making it a sealed state using. Next, using a differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corporation), the aluminum pan in which the measurement sample was sealed was heated from room temperature to 300 ° C. at a temperature increase rate of 20 ° C./min under a nitrogen atmosphere. and held at 300° C. for 3 minutes. Thereafter, the aluminum pan was immersed in liquid nitrogen and rapidly cooled to lower the temperature to room temperature at a temperature lowering rate of 100° C./min. Subsequently, after being left at room temperature for 30 minutes, the differential scanning calorimeter DSC-50 (manufactured by Shimadzu Corporation) was again used to raise the temperature from room temperature to 300°C at a heating rate of 20°C/min. This cycle is repeated three times, and the melting point difference (Tm1-Tm3) is calculated from the melting point (Tm1) measured at the first temperature drop to room temperature and the melting point (Tm3) measured at the third temperature drop to room temperature. asked.

<Heat aging resistance test 1 (measurement of retention rate of elongation at break after heat treatment)>
In order to evaluate the heat aging resistance of the thermoplastic polyester elastomer resin compositions of Examples and Comparative Examples, the following elongation retention rate test at break was conducted.

(Preparation of test piece)
First, the above thermoplastic polyester elastomer resin composition was injected from an injection molding machine with a cylinder temperature +20° C. of the melting point of the above resin composition and a mold temperature of 30° C. to obtain a length of 100 mm×width of 100 mm. An injection molded product with a thickness of 2.0 mm was obtained. Next, a test piece was produced by punching out a JIS No. 3 dumbbell shape along the direction of flow of the injection-molded product.

(Dry heat treatment and elongation retention measurement at break)
The test piece was treated in a gear-type hot air dryer at 175°C for 240 hours. Thereafter, the absolute tensile elongation (elongation retention rate at break) of the test piece was measured according to JIS K6251:2010. The absolute tensile elongation (elongation retention rate at break) of the test piece was evaluated according to the following criteria. A can be evaluated as superior to B.
A: Absolute tensile elongation (elongation retention rate at break) of 100% or more.
B: Absolute tensile elongation (elongation retention rate at break) of less than 100%.

<Heat aging resistance test 2 (crack confirmation by winding test after heat treatment)>
In order to evaluate the heat aging resistance of the thermoplastic polyester elastomer resin composition of each example and comparative example, cracks were confirmed by the following winding test after heat treatment.

(Preparation of test piece)
A test piece (JIS No. 3 dumbbell shape) of the thermoplastic polyester elastomer composition was prepared in the same manner as in the heat aging resistance test 1 above.

(Dry heat treatment, winding test)
The test piece was treated in a gear-type hot air dryer at 175°C for 240 hours. Then, after sufficiently cooling the test piece, it is further cooled at -25 ° C. for 5 hours or more, and in the cooled state, it is wound around a mandrel according to ASTM D 618, and whether cracks occur in the cross section of the test piece. No, I observed. The observation results were evaluated according to the following criteria.
A: No crack occurs at all.
B: Winding is possible, but cracks are slightly observed.
C: Unable to wind, or many cracks.

<pH value measurement of inorganic filler B by pigment test method>
The pH of inorganic filler B was measured according to the test method of JIS K 5101-17-2:2004.

The following raw materials were used in Examples and Comparative Examples.
<Thermoplastic polyester elastomer A>
As the thermoplastic polyester elastomer A, the following compounds were prepared.

(Thermoplastic polyester elastomer A-1)
100 parts by mass of aliphatic polycarbonate diol (trade name: "Carbonate Diol UH-CARB 200", molecular weight 2000, 1,6-hexanediol type, manufactured by Ube Industries, Ltd.) and 8.6 parts by mass of diphenyl carbonate were placed in reaction vessels. and reacted at a temperature of 205° C. and 130 Pa. After 2 hours, the content in the reaction vessel was cooled to obtain an aliphatic polycarbonate diol (number average molecular weight: 10,000). Next, 30 parts by mass of the aliphatic polycarbonate diol (PCD) and 70 parts by mass of polybutylene terephthalate (PBT) having a number average molecular weight of 30,000 were charged into a reaction vessel, and 1 After the content was made transparent by stirring for a period of time, the content was taken out and cooled to produce a thermoplastic polyester elastomer A-1. The thermoplastic polyester elastomer A-1 had a melting point of 212° C., a reduced viscosity of 1.20 dl/g, and a terminal acid value of 45 eq/ton.

(Thermoplastic polyester elastomer A-2)
100 parts by mass of aliphatic polycarbonate diol (trade name: "Carbonate Diol UH-CARB 200", molecular weight 2000, 1,6-hexanediol type, manufactured by Ube Industries, Ltd.) and 8.6 parts by mass of diphenyl carbonate were placed in reaction vessels. and reacted at a temperature of 205° C. and 130 Pa. After 2 hours, the content in the reaction vessel was cooled to obtain an aliphatic polycarbonate diol (number average molecular weight: 10,000). Next, 43 parts by mass of the aliphatic polycarbonate diol (PCD) and 57 parts by mass of polybutylene terephthalate (PBT) having a number average molecular weight of 30,000 were charged into a reaction vessel, and 1 After the content was made transparent by stirring for a period of time, the content was taken out and cooled to produce a thermoplastic polyester elastomer A-2. The thermoplastic polyester elastomer A-2 had a melting point of 207° C., a reduced viscosity of 1.21 dl/g, and a terminal acid value of 44 eq/ton.

(Thermoplastic polyester elastomer A-3)
Using dimethyl terephthalate, 1,4-butanediol and poly(tetramethylene oxide) glycol having a number average molecular weight of 1000 as raw materials, a polycondensation reaction was performed using a reaction vessel equipped with a stirring blade, and the soft segment content was 36% by mass. A thermoplastic polyester elastomer A-3 was produced. The thermoplastic polyester elastomer A-3 had a melting point of 201° C., a reduced viscosity of 1.75 dl/g, and a terminal acid value of 50 eq/ton.

<Inorganic filler B>
As inorganic filler B, the following inorganic compounds were prepared.
(B-1) Calcium carbonate (trade name: “Whiten P-50” manufactured by Toyo Fine Chemicals, average particle size 18 μm, pH 9.5)
(B-2) Wollastonite (trade name: "VM8", manufactured by Hayashi Kasei Co., Ltd., average particle size 11 µm, pH = 10.5)
(B-3) Kaolin (trade name: “ASP-90G”, manufactured by BASF, average particle size 0.2 μm, pH 6-8).

<Olefin Elastomer C>
As the olefinic elastomer C, the following organic compounds were prepared. Although (C-2) and (C-3) below are not classified as the olefinic elastomer C, they are described in this column for comparison with the olefinic elastomer C.
(C-1) Styrene-ethylene/butylene-styrene block copolymer (trade name: “Tuftec L523”, manufactured by Asahi Kasei Corporation, styrene/ethylene/butylene ratio = 6/94 (mass ratio), MFR (190 ° C., 2 .16 kg) = 4.5 g/10 min)
(C-2) polyethylene (trade name: "HI-ZEX 6203B", manufactured by PRAIM POLYMER, polyethylene = 100 (weight ratio), MFR (190 ° C., 2.16 kg) = 0.35 g / 10 min)
(C-3) Ethylene tetrafluoroethylene (trade name: “AH-2000” manufactured by Asahi Glass Co., Ltd., MFR (297° C., 5.00 kg)=25 g/10 min).

<Epoxy group-containing polyolefin D>
As the epoxy group-containing polyolefin D, the following organic compounds were prepared.
(D-1) Epoxy group-containing olefin copolymer (trade name: “Bond First BF-7M” manufactured by Sumitomo Chemical Co., Ltd., epoxy value: 0.4 meq/g).

<Preparation of Thermoplastic Polyester Elastomer Resin Compositions of Examples 1 to 11 and Comparative Examples 1 to 4>
The above thermoplastic polyester elastomer A, inorganic filler B, olefin elastomer C and epoxy group-containing polyolefin D are combined and ratios (parts by mass) shown in Table 1, and the cylinder temperature is set to 180 to 230 ° C. Twin-screw extrusion Pellets of the thermoplastic polyester elastomer resin compositions of Examples 1 to 11 and Comparative Examples 1 to 4 were obtained by kneading them with the twin screw extruder. . Using the pellets described above, the various evaluations described above were performed. Table 1 shows the results.

<Discussion>
According to Table 1, it is understood that the thermoplastic polyester elastomer resin compositions of Examples 1 to 11 have both excellent acid resistance and heat aging resistance. Especially from the comparison between Example 1 and Example 2, it is understood that the effect of further improving acid resistance is obtained by increasing the amount of inorganic filler B added. Furthermore, from the comparison between Example 2 and Example 4, it is understood that the higher the basicity of the inorganic filler B improves the neutralizing ability and further improves the acid resistance. Example 5, in which the thermoplastic polyester elastomer A had a high soft segment ratio, had slightly lower acid resistance than the other examples, but had improved flexibility. In Example 6, in which the epoxy group-containing polyolefin D was not added, the acid resistance was good, but the dispersibility of the olefin elastomer C was lowered, so the heat aging resistance was slightly lowered. In Example 7, in which the amount of the olefinic elastomer C added was increased, the acid resistance was good, but the heat aging resistance was slightly lowered due to the increase in the olefin component. Examples 8 and 9 are examples in which polyethylene or ethylene tetrafluoroethylene was used as the olefinic elastomer C. Although the acid resistance was good, the hardness was improved and the flexibility was lowered. In Example 10, in which the olefinic elastomer C and the epoxy group-containing polyolefin D were not added, although the acid resistance was good, the hardness was improved and the flexibility was lowered. In Example 11, in which the content of the inorganic filler B was increased, the flexibility was lowered and the absolute elongation was slightly lowered due to the increase in hardness due to the inorganic filler component. On the other hand, the thermoplastic polyester elastomer resin compositions of Comparative Examples 1 to 4 were inferior to those of Examples in at least acid resistance and at least one of hardness and heat aging resistance.

Specifically, Comparative Example 1, in which inorganic filler B was not added, was inferior in acid resistance. In Comparative Example 2, glass beads were used as the inorganic filler B, but the acid resistance was poor. Comparative Example 3 was an example in which an excessive amount of inorganic filler B was added, and poor dispersion occurred and the hardness was improved, resulting in poor acid resistance, heat aging resistance and flexibility. Comparative Example 4 was inferior in acid resistance and heat aging resistance because the soft segment of the thermoplastic polyester elastomer A was polyether.

As described above, the thermoplastic polyester elastomer resin composition according to the present embodiment is characterized by excellent acid resistance and excellent heat aging resistance.

Although the embodiments and examples of the present invention have been described above, it is originally planned to appropriately combine the configurations of the above-described embodiments and examples.

It should be considered that the embodiments and examples disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the meaning and range of equivalents of the scope of the claims.

Claims (9)

A thermoplastic polyester elastomer resin composition containing a resin component containing a thermoplastic polyester elastomer A and an inorganic filler B,
The thermoplastic polyester elastomer A is formed by combining hard segments and soft segments,
The hard segment is made of a polyester composed of an aromatic dicarboxylic acid and an aliphatic or alicyclic diol,
The soft segment comprises an aliphatic polycarbonate,
The thermoplastic polyester elastomer resin composition contains 1 part by mass or more and 40 parts by mass or less of the inorganic filler B with respect to 100 parts by mass of the resin component containing the thermoplastic polyester elastomer A,
A thermoplastic polyester elastomer resin composition, wherein the thermoplastic polyester elastomer resin composition has an erosion depth of 1.0 mm or less as measured according to the acid resistance test method. The resin component contains an olefinic elastomer C,
2. The thermoplastic polyester elastomer resin according to claim 1, wherein the resin component contains 10 parts by mass or more and 50 parts by mass or less of the olefin elastomer C with respect to the thermoplastic polyester elastomer A of 50 parts by mass or more and 90 parts by mass or less. Composition. 3. The thermoplastic polyester elastomer resin composition according to claim 2, wherein said olefin elastomer C is a styrene elastomer. The resin component contains an epoxy group-containing polyolefin D,
4. The resin component according to claim 2 or 3, wherein the epoxy group-containing polyolefin D is contained in an amount of 1 part by mass or more and 10 parts by mass or less with respect to a total of 100 parts by mass of the thermoplastic polyester elastomer A and the olefin elastomer C. A thermoplastic polyester elastomer resin composition as described. The thermoplastic polyester elastomer resin composition according to any one of claims 1 to 4, wherein the inorganic filler B has a pH of 9 or more and 11 or less. 6. Any one of claims 1 to 5, wherein the thermoplastic polyester elastomer resin composition has a hardness of D40 or more and D50 or less measured according to the hardness test method for thermoplastics specified in ASTM D 2240. The thermoplastic polyester elastomer resin composition according to the above item. The thermoplastic polyester elastomer A has a melting point of 150° C. or higher and 225° C. or lower,
Using a differential scanning calorimeter, the temperature is raised from room temperature to 300°C at a temperature increase rate of 20°C/min, held at 300°C for 3 minutes, and then cooled to room temperature at a temperature decrease rate of 100°C/min. Repeating the cycle three times. and the melting point (Tm3) of the thermoplastic polyester elastomer A measured at the third temperature drop in the operation. The thermoplastic polyester elastomer resin composition according to any one of claims 1 to 6, wherein the melting point difference (Tm1-Tm3) is 0°C or higher and 50°C or lower. The thermoplastic polyester elastomer resin composition according to any one of claims 1 to 7, which is for extrusion molding. The thermoplastic polyester elastomer resin composition according to any one of claims 1 to 8, which is for cable coating.