JP2021054933A - Thermoplastic polyurethane, method for producing the same, and molded article - Google Patents

Abstract

To provide: a thermoplastic polyurethane that can be applied to injection molding, has a short solidification time while being a non-yellowing type, and excels in high-cycle performance; a method for producing the same; and a molded article obtained using the thermoplastic polyurethane.SOLUTION: There is provided a thermoplastic polyurethane comprising: a constitutional unit derived from a long-chain diol; a constitutional unit derived from a short-chain diol; and a constitutional unit derived from 1,4-bis(isocyanatomethyl)cyclohexane. There are also provided a method for producing a thermoplastic polyurethane, comprising a step of reacting a long-chain diol, a short-chain diol, and 1,4-bis(isocyanatomethyl)cyclohexane, as well as a molded article comprising the thermoplastic polyurethane.SELECTED DRAWING: None

Description

The present invention relates to a thermoplastic polyurethane, a method for producing a thermoplastic polyurethane, and a molded product.

A thermoplastic polyurethane obtained by using an aliphatic diisocyanate or an alicyclic diisocyanate as a diisocyanate component is useful as a so-called non-yellowing type polyurethane which is hard to yellow even by an external stimulus such as light. However, since the non-yellowing type polyurethane generally has a slow solidification rate, the molding cycle tends to be long, and it cannot be said that it is very useful as a resin raw material for injection molding. Therefore, non-yellowing type polyurethane is mainly used as a resin raw material for extrusion molding.

On the other hand, so-called yellowing type polyurethane obtained by using aromatic diisocyanate as a diisocyanate component tends to have a faster solidification rate than non-yellowing type polyurethane. For this reason, yellowing type polyurethane is mainly developed as a resin material for injection molding in applications where yellowing is not a problem.

However, there is a strong desire to improve the productivity of various non-yellowing molded products by injection molding non-yellowing type polyurethane. As a related prior art, for example, in order to improve the moldability of a polyurethane obtained by using a diisocyanate component such as an aliphatic diisocyanate, the above-mentioned polyurethane is blended with an appropriate amount of an acrylic copolymer and acrylic fine particles to form a thermoplastic material. Elastomers have been proposed (Patent Document 1).

Japanese Unexamined Patent Publication No. 2001-172497

The elastomer proposed in Patent Document 1 contains polyurethane obtained by using an aliphatic diisocyanate, but has improved moldability to some extent. However, since the elastomer proposed in Patent Document 1 contains a resin component other than polyurethane, the texture and characteristics peculiar to polyurethane tend to be impaired. Therefore, a polyurethane-based resin material that is a non-yellowing type, has a short solidification time, and retains the properties peculiar to polyurethane has not been found so far.

The present invention has been made in view of the problems of the prior art, and the subject thereof is that although it is a non-yellowing type, it has a short solidification time and excellent high cycle property. The purpose is to provide a thermoplastic polyurethane applicable to injection molding. Another object of the present invention is to provide the above-mentioned method for producing a thermoplastic polyurethane and a molded product obtained by using the above-mentioned thermoplastic polyurethane.

That is, according to the present invention, the thermoplastic polyurethane shown below is provided.
[1] A thermoplastic polyurethane having a structural unit derived from a long-chain diol, a structural unit derived from a short-chain diol, and a structural unit derived from 1,4-bis (isocyanatomethyl) cyclohexane.
[2] The thermoplastic polyurethane according to the above [1], wherein the long chain diol is a polycarbonate polyol.
[3] The thermoplastic polyurethane according to the above [1] or [2], wherein the long-chain diol has a number average molecular weight of 500 to 5,000.
[4] The thermoplastic polyurethane according to any one of [1] to [3], wherein the long-chain diol has a number average molecular weight of 1,000 to 2,500.
[5] The mass ratio of the content (L) of the structural unit derived from the long-chain diol to the content (S) of the structural unit derived from the short-chain diol is L: S = 60: 40 to 98. : 2. The thermoplastic polyurethane according to any one of the above [1] to [4].
[6] The thermoplastic polyurethane according to any one of the above [1] to [5], wherein the 1,4-bis (isocyanatomethyl) cyclohexane contains 70 mol% or more of a trans form.
[7] The tensile strength measured according to JIS K 7311: 1995 is 20 to 50 MPa, the elastic modulus measured according to JIS K 7311: 1995 is 40% or more, and JIS The thermoplastic polyurethane according to any one of the above [1] to [6], wherein the compressive permanent strain measured according to K 6262: 2013 is 10 to 35%.
[8] The item according to any one of [1] to [7] obtained by reacting the long-chain diol, the short-chain diol, and the 1,4-bis (isocyanatomethyl) cyclohexane by a one-shot method. The thermoplastic polyurethane described.

Further, according to the present invention, the following method for producing a thermoplastic polyurethane is provided.
[9] A method for producing a thermoplastic polyurethane, which comprises a step of reacting a long-chain diol, a short-chain diol, and 1,4-bis (isocyanatomethyl) cyclohexane.
[10] The method for producing a thermoplastic polyurethane according to the above [9], wherein the long chain diol, the short chain diol, and the 1,4-bis (isocyanatomethyl) cyclohexane are reacted by a one-shot method.
[11] The isocyanate group (NCO) of the 1,4-bis (isocyanatomethyl) cyclohexane and the hydroxyl groups (OH) of the long-chain diol and the short-chain diol are combined with NCO / OH = 0.95-1. The method for producing a thermoplastic polyurethane according to the above [9] or [10], wherein the reaction is carried out at a molar ratio of 05.

Further, according to the present invention, the following molded products are provided.
[12] A molded product made of the thermoplastic polyurethane according to any one of the above [1] to [8].

According to the present invention, by using a specific aliphatic diisocyanate, a thermoplastic polyurethane applicable to injection molding, which is a non-yellowing type but has a short solidification time and excellent high cycle property, is provided. be able to. Further, by using a specific aliphatic diisocyanate, it is possible to provide a thermoplastic polyurethane having a high rebound resilience, a small compression set, and a sufficient tensile strength. Further, according to the present invention, it is possible to provide the above-mentioned method for producing a thermoplastic polyurethane and a molded product obtained by using the above-mentioned thermoplastic polyurethane.

<Thermoplastic polyurethane>
Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments. The thermoplastic polyurethane of the present embodiment (hereinafter, also simply referred to as “polyurethane”) is composed of a structural unit derived from a long-chain diol, a structural unit derived from a short-chain diol, and 1,4-bis (isocyanatomethyl) cyclohexane. Has a building block of origin. Hereinafter, the details of the polyurethane of the present embodiment will be described.

(Long chain diol)
The polyurethane of this embodiment has a structural unit derived from a long chain diol. The long chain diol is a high molecular weight compound (monomer) having two hydroxyl groups in its molecular structure, a macromonomer, a polymer, or the like. Examples of the long-chain diol include polycarbonate polyol, polyether polyol, polyester polyol, polyolefin polyol, polymethacrylate polyol and the like.

Examples of the polycarbonate polyol include polytrimethylene carbonate polyol, polytetramethylene carbonate polyol, polypentamethylene carbonate polyol, polyneopentyl carbonate polyol, polyhexamethylene carbonate polyol, poly (1,4-cyclohexanedimethylene carbonate) polyol, and polydeca. Methylene carbonate polyol and the like can be mentioned.

Examples of the polyether polyol include those obtained by polymerizing or copolymerizing an alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) or a heterocyclic ether (tetrahydrofuran, etc.). More specifically, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyethylene glycol-polytetramethylene glycol (block or random copolymer), polytetramethylene ether glycol, polyhexamethylene glycol and the like can be mentioned.

Polyester polyols include aliphatic dicarboxylic acids (eg, succinic acid, adipic acid, sebacic acid, glutaric acid, azelaic acid, etc.) and aromatic dicarboxylic acids (eg, isophthalic acid, terephthalic acid, etc.) and low molecular weight. Glycos (eg, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, 1,6-hexamethylene glycol, neopentyl glycol, 1,4-bishydroxymethylcyclohexane) Etc.) and the polymerized product. More specifically, polyethylene adipate polyol, polybutylene adipate polyol, polyhexamethylene adipate polyol, polyneopentyl adipate polyol, polyethylene adipate polyol, polybutylene adipate polyol, polyneopentyl adipate polyol, polyhexyl adipate polyol, poly-3. -Methylpentane adipate polyol, polybutylene isophthalate polyol and the like can be mentioned.

Further, as the polyester polyol, ring-opening polymerization of lactones such as ε-caprolactone and γ-valerolactone and lactides such as L-lactide and D-lactide is carried out using the above low molecular weight glycols as an initiator. Examples of the obtained polycaprolactone polyol, polyvalerolactone polyol and the like can be mentioned.

Examples of the polyolefin polyol include polybutadiene glycol, polyisoprene glycol, and hydrides thereof. Examples of the polymethacrylate polyol include α, ω-polymethylmethacrylate polyol and α, ω-polybutyl methacrylate polyol.

As the long-chain diol, a polycarbonate polyol is preferable, and a polyhexamethylene carbonate polyol is particularly preferable. By having a structural unit derived from a polycarbonate polyol, it is possible to obtain a thermoplastic polyurethane having excellent heat resistance and hydrolysis resistance.

The number average molecular weight of the long-chain diol is preferably 500 to 5,000, more preferably 1,000 to 2,500, and particularly preferably 1,200 to 2,000. By using a long-chain diol whose number average molecular weight is within the above range, the solidification rate can be further increased, and a thermoplastic polyurethane having excellent transparency can be obtained.

(Short chain diol)
The polyurethane of this embodiment has a structural unit derived from a short chain diol. The short chain diol is a low molecular weight compound having two hydroxyl groups in its molecular structure, and is a component used as a so-called "chain extender". Examples of short chain diols include ethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, and 3-. Aliphatic glycols such as methyl-1,5-pentanediol; alicyclic glycols such as 1,4-bishydroxymethylcyclohexane and 2-methyl-1,1-cyclohexanedimethanol; can be mentioned. Of these, 1,4-butanediol is particularly preferable.

The mass ratio of the content (L) of the structural unit derived from the long-chain diol and the content (S) of the structural unit derived from the short-chain diol in the thermoplastic polyurethane is L: S = 60: 40 to It is preferably 98: 2, more preferably L: S = 70: 30 to 95: 5, and particularly preferably L: S = 75: 25 to 90:10. The mass ratio (L: S) of the content (L) of the structural unit derived from the long-chain diol and the content (S) of the structural unit derived from the short-chain diol is within the above range to solidify. The speed can be further increased, and the thermoplastic polyurethane having excellent transparency can be obtained.

(Polyisocyanate)
The polyurethane of the present embodiment has a structural unit derived from 1,4-bis (isocyanatomethyl) cyclohexane (hereinafter, also referred to as “1,4-H _{6 XDI”) which is a polyisocyanate.} By having a structural unit derived from 1,4-H ₆ XDI, it is possible to obtain a so-called non-yellowing type thermoplastic polyurethane which is hard to yellow even by the action of light. Further, by having a structural unit derived from 1,4-H ₆ XDI, the solidification time is shortened even though it is a non-yellowing type. Therefore, it is possible to obtain a thermoplastic polyurethane that has excellent high cycle properties and is applicable to injection molding. Further, since the moldability is improved without blending other resin components, the properties peculiar to polyurethane are maintained. Further, by using 1,4-H ₆ XDI, it is possible to obtain a thermoplastic polyurethane having a high rebound resilience, a small compression set, and a sufficient tensile strength.

1,4-Bis (isocyanatomethyl) cyclohexane (1,4-H ₆ XDI) usually contains a cis-trans isomer. _{The 1,4-H 6} XDI used as the polyisocyanate in the polyurethane of the present embodiment preferably contains 70 mol% or more of the trans form, and preferably 70 to 99 mol%. _{By using 1,4-H 6} XDI having a transformer content of 70 mol% or more, the solidification rate can be further increased.

_{If necessary, polyisocyanates other than 1,4-H 6} XDI (other polyisocyanates) can be used as long as the effects of the present invention are not impaired. Other polyisocyanates include aliphatic polyisocyanates, alicyclic polyisocyanates ( _{excluding 1,4-H 6} XDI), aromatic polyisocyanates, and aromatic aliphatic polyisocyanates used in the production of general polyurethanes. Isocyanate and the like can be mentioned.

(Thermoplastic polyurethane)
Since the polyurethane of the present embodiment _{has a structural unit derived from 1,4-H 6} XDI, as described above, it has not only the property of being a non-yellowing type but having a short solidification time, but also having a rebound resilience. In addition to being high, it also exhibits characteristics such as low compression set and sufficient tensile strength. More specifically, the tensile strength of the polyurethane of the present embodiment measured in accordance with JIS K 7311: 1995 is preferably 20 to 50 MPa, more preferably 25 to 45 MPa. The elastic modulus of the polyurethane of the present embodiment measured in accordance with JIS K 7311: 1995 is preferably 40% or more, more preferably 45 to 60%. Further, the compression set of the polyurethane of the present embodiment measured according to JIS K 6262: 2013 is preferably 10 to 35%, more preferably 20 to 30%.

Further, when producing the urethane resin of the present embodiment, it is preferable to react a long-chain diol, a short-chain diol, and 1,4-bis (isocyanatomethyl) cyclohexane by a one-shot method. The one-shot method is easier to operate than the so-called prepolymer method and is suitable for industrial production. Further, in the manufacturing process, the continuous method is preferable. The continuous method has higher productivity than the so-called batch method and is suitable for industrial production.

<Manufacturing method of thermoplastic polyurethane>
The method for producing a thermoplastic polyurethane according to an embodiment of the present invention is a method suitable for producing the above-mentioned polyurethane, and is a long-chain diol, a short-chain diol, and 1,4-bis (isocyanatomethyl) cyclohexane. It has a step of reacting (1,4-H _{6 XDI).}

The method for reacting each component (long-chain diol, short-chain diol, and 1,4-H ₆ XDI) is not particularly limited. Specifically, (i) a one-shot method in which a long-chain diol, a short-chain diol, and 1,4-H ₆ XDI are reacted together; (ii) a reaction of a long-chain diol and 1,4-H ₆ XDI. A prepolymer method in which a short-chain diol, which is a chain extender, is reacted with the obtained isocyanate-terminated prepolymer after the isocyanate-terminated prepolymer is obtained. Above all, it is preferable to react each component by (i) one-shot method. The one-shot method is preferable because the step of manufacturing the prepolymer is not required and the number of work steps is smaller than that of the prepolymer method.

The long-chain diol and the short-chain diol may be added to the reaction system individually or may be mixed in advance and added to the reaction system. Further, the isocyanate group (NCO) of 1,4-H ₆ XDI and the hydroxyl group (OH) of the long chain diol and the chain diol can be reacted at a molar ratio of NCO / OH = 0.95 to 1.05. Preferably, the reaction is more preferably carried out at a molar ratio of NCO / OH = 0.97 to 1.03.

<Molded product>
The molded product according to the embodiment of the present invention is composed of the above-mentioned thermoplastic polyurethane. The molded product of the present embodiment has, for example, various desired shapes such as pellet-shaped, plate-shaped, strand-shaped, film-shaped, sheet-shaped, pipe-shaped, hollow-shaped, box-shaped, etc. It can be manufactured by molding into.

Examples of the molding method include a thermoforming method using a specific mold, an injection molding method, a thermoforming processing method such as an extrusion molding method, and the like. Of these, an injection molding method that can obtain more molded products in a short time is preferable. As described above, polyurethane used as a molding raw material has a short solidification time and excellent high cycle property even though it is a non-yellowing type. Therefore, even in the case of mass production in a short time by the injection molding method, problems such as sprue breakage are less likely to occur, and the production yield can be improved.

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

<Manufacturing of polyurethane>
(Example 1: Pellet 1)
450.0 g of polyhexamethylene carbonate polyol (trade name "UH-200", manufactured by Ube Industries, Ltd., number average molecular weight 2,000) and 50.0 g of 1,4-butanediol were placed in a reaction vessel and added to 110 ° C. It was warm. _{Next, 151.4 g of 1,4-H 6} XDI (trade name "Fortimo", manufactured by Mitsui Chemicals, Inc.) heated to 60 ° C. was added, and the mixture was stirred for 12 seconds to react. The obtained reaction product was transferred to a tray and aged at 100 ° C. for 3 hours to obtain a lump. The pulverized product obtained by crushing the obtained lump product was put into an extruder, extruded into a strand shape, and then cut and pelletized to obtain a thermoplastic polyurethane pellet (pellet 1).

(Examples 2 to 4, Comparative Examples 1 to 4: Pellets 2 to 8)
Pellets (pellets 2 to 8) of thermoplastic polyurethane were obtained in the same manner as in Example 1 above, except that the formulations (unit: g) shown in the middle of Table 1 were used.

The meanings of the product names and abbreviations in Table 1 are shown below.
-UH-200: Polyhexamethylene carbonate polyol, manufactured by Ube Industries, Ltd., number average molecular weight 2,000
-PTMG2000: Polytetramethylene glycol, manufactured by Mitsubishi Chemical Corporation, number average molecular weight 2,000
-Plaxel 220: Polycaprolactone diol, manufactured by Daicel, with a number average molecular weight of 2,000.
・ 1,4-BD: 1,4-butanediol ・ EG: Ethylene glycol ・ 1,4-H ₆ XDI: 1,4-bis (isocyanatomethyl) cyclohexane (trans form content ratio 70% or more)
・ HDI: Hexamethylene diisocyanate ・ MDI: Diphenylmethane diisocyanate

<Evaluation (1)>
(Solidification time)
Using pellets 1 to 8 as molding materials, an injection molding machine (model name "HM7-C", manufactured by Nissei Resin Industry Co., Ltd.) and a thick flat plate mold (3.5 cm x 4 cm x 2 mm) are used, and the rear temperature is 210. Injection molding was performed under the conditions of ° C., intermediate temperature 215 ° C., front temperature 215 ° C., and nozzle temperature 220 ° C. to obtain injection molded plates 1-1 to 8-1. At that time, the time during which the injection-molded plate was separated from the mold without causing sprue breakage and without deformation was measured as "solidification time (seconds)". The results are shown in Table 2.

(Heat-resistant)
Using pellets 1 to 8 as molding raw materials, injection molding is performed using an injection molding machine (model "SAV-100-75", manufactured by Yamashiro Seiki Co., Ltd.) and a thick flat plate mold (10 cm x 10 cm x 2 mm) for injection. Molded plates 1-2-8-2 were obtained. The obtained injection molded plate was placed in a hot air dryer (manufactured by Kyowa Riki Seisakusho Co., Ltd.) and stored at 120 ° C. for 6 weeks. The tensile strength of the injection-molded plate before and after the hot air dryer was charged was measured, and the "tensile strength retention rate (%)" was calculated with the value of the tensile strength before charging as the initial value. The results are shown in Table 2.

(Hydrolysis resistance)
Using pellets 1 to 8 as molding raw materials, injection molding is performed using an injection molding machine (model "SAV-100-75", manufactured by Yamashiro Seiki Co., Ltd.) and a thick flat plate mold (10 cm x 10 cm x 2 mm) for injection. Molded plates 1-3 to 8-3 were obtained. The obtained injection molded plate was placed in a constant temperature and humidity chamber (model "IH400", manufactured by Yamato Scientific Co., Ltd.) and stored at 80 ° C. and 95% RH for 6 weeks. The tensile strength of the injection-molded plate before and after charging into the constant temperature and humidity chamber was measured, and the "tensile strength retention rate (%)" was calculated with the value of the tensile strength before charging as the initial value. The results are shown in Table 2.

<Evaluation (2)>
(Tensile strength)
Using pellets 1 to 8 as molding raw materials, injection molding is performed using an injection molding machine (model "SAV-100-75", manufactured by Yamashiro Seiki Co., Ltd.) and a thick flat plate mold (10 cm x 10 cm x 2 mm) for injection. I got a molded plate. According to JIS K 7311: 1995, test pieces 1-1 to 8-1 were prepared using the obtained injection molded plate, and the tensile strength (MPa) was measured. The results are shown in Table 3.

(Repulsive modulus)
Using pellets 1 to 8 as molding raw materials, injection molding is performed using an injection molding machine (model "SAV-100-75", manufactured by Yamashiro Seiki Co., Ltd.) and a thick flat plate mold (10 cm x 10 cm x 2 mm) for injection. I got a molded plate. According to JIS K 7311: 1995, test pieces 1-2 to 8-2 were prepared using the obtained injection molded plate, and the elastic modulus (%) was measured. The results are shown in Table 3.

(Compressive permanent strain)
Using pellets 1 to 8 as molding raw materials, an injection molding machine (model "SAV-100-75", manufactured by Yamashiro Seiki Co., Ltd.) and a cylindrical mold (diameter 29.0 ± 0.5 mm, thickness 12.5 ±) 0.5 mm) was used for injection molding to obtain test pieces 1-3 to 8-3. According to JIS K 6262: 2013, the compression set (%) of the obtained test piece was measured under the conditions of 70 ° C. and 24 hours. The results are shown in Table 3.

<Evaluation (3)>
(Light resistance)
Using pellets 1 to 8 as molding raw materials, injection molding is performed using an injection molding machine (model "SAV-100-75", manufactured by Yamashiro Seiki Co., Ltd.) and a thick flat plate mold (10 cm x 10 cm x 2 mm) for injection. I got a molded plate. The injection-molded plate obtained by using a press machine was pressed to prepare press sheets 1-1 to 8-1 having a thickness of 0.5 mm. The produced press sheet was subjected to a light irradiation test under the conditions shown below, and then the color difference (ΔE, Δb ^* ) was measured and calculated using a spectrophotometer. The results are shown in Table 4.
・ Light source: Metering lamp ・ Irradiation amount: 150MJ × 33.6 hours ・ Black panel temperature: 63 ℃

(chemical resistance)
Using pellets 1 to 8 as molding raw materials, injection molding is performed using an injection molding machine (model "SAV-100-75", manufactured by Yamashiro Seiki Co., Ltd.) and a thick flat plate mold (10 cm x 10 cm x 2 mm) for injection. I got a molded plate. The injection-molded plate obtained by using a press machine was pressed to prepare a press sheet 1-2 to 8-2 having a thickness of 0.5 mm. The prepared press sheet was immersed in ethanol and oleic acid for 24 hours, respectively, and the coefficient of linear expansion (%) was measured. The results are shown in Table 4.

(NOX resistance)
Using pellets 1 to 8 as molding raw materials, injection molding is performed using an injection molding machine (model "SAV-100-75", manufactured by Yamashiro Seiki Co., Ltd.) and a thick flat plate mold (10 cm x 10 cm x 2 mm) for injection. I got a molded plate. The injection-molded plate obtained by using a press machine was pressed to prepare press sheets 1-3 to 8-3 having a thickness of 0.5 mm. The produced press sheet was subjected to a NOX resistance test in accordance with JIS L 0855: 2005, and then the color difference (ΔE, Δb ^* ) was measured and calculated using a spectrophotometer. The results are shown in Table 4.

The thermoplastic polyurethane of the present invention is useful as a resin raw material for producing a non-yellowing type molded product made of polyurethane by injection molding.

Claims (12)

A thermoplastic polyurethane having a structural unit derived from a long chain diol, a structural unit derived from a short chain diol, and a structural unit derived from 1,4-bis (isocyanatomethyl) cyclohexane. The thermoplastic polyurethane according to claim 1, wherein the long-chain diol is a polycarbonate polyol. The thermoplastic polyurethane according to claim 1 or 2, wherein the long-chain diol has a number average molecular weight of 500 to 5,000. The thermoplastic polyurethane according to any one of claims 1 to 3, wherein the long-chain diol has a number average molecular weight of 1,000 to 2,500. The mass ratio of the content (L) of the structural unit derived from the long-chain diol to the content (S) of the structural unit derived from the short-chain diol is L: S = 60: 40 to 98: 2. The thermoplastic polyurethane according to any one of claims 1 to 4. The thermoplastic polyurethane according to any one of claims 1 to 5, wherein the 1,4-bis (isocyanatomethyl) cyclohexane contains 70 mol% or more of a trans form. The tensile strength measured in accordance with JIS K 7311: 1995 is 20 to 50 MPa.
The elastic modulus measured in accordance with JIS K 7311: 1995 is 40% or more.
The thermoplastic polyurethane according to any one of claims 1 to 6, wherein the compression set has a compression set of 10 to 35% measured according to JIS K 6262: 2013. The thermoplastic polyurethane according to any one of claims 1 to 7, which is obtained by reacting the long chain diol, the short chain diol, and the 1,4-bis (isocyanatomethyl) cyclohexane by a one-shot method. A method for producing a thermoplastic polyurethane, which comprises a step of reacting a long chain diol, a short chain diol, and 1,4-bis (isocyanatomethyl) cyclohexane. The method for producing a thermoplastic polyurethane according to claim 9, wherein the long-chain diol, the short-chain diol, and the 1,4-bis (isocyanatomethyl) cyclohexane are reacted by a one-shot method. The isocyanate group (NCO) of the 1,4-bis (isocyanatomethyl) cyclohexane and the hydroxyl group (OH) of the long-chain diol and the short-chain diol are arranged in a molar amount of NCO / OH = 0.95 to 1.05. The method for producing a thermoplastic polyurethane according to claim 9 or 10, wherein the reaction is carried out by a ratio. A molded product made of the thermoplastic polyurethane according to any one of claims 1 to 8.