JPH09316164A - Composition for thermoplastic polyurethane resin excellent in solubility, production of resin therefrom, and molded item made therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermoplastic polyurethane excellent in physical properties and solubility in solvents by reacting a specific long-chain polyol with a mixture of 4,4'-diphenylmethane diisocyanate and its isomer. SOLUTION: This compsn. for a thermoplastic polyurethane resin comprises an isocyanate component comprising 50-98wt.% 4,4'-diphenylmethane diisocyanate and 50-2wt.% its isomer and a long-chain polyol having a hydroxyl value of 50-150mgKOH/g in a molar ratio of NCO/OH of 0.85-1.15. Pellets and thermally molded items are obtd. from the compsn. The isocyanate component may contain another isocyanate. The polyol may be a polyester polyol, a polyether polyol, or an another-type polyol and pref. has a mol.wt. of 850-5,000. The compsn. may futher contain a chain extender such as ethylene glycol. A polyurethane resin obtd. from the compsn. can be used not only for molded items but also as solns. for adhesives or coating materials.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composition for thermoplastic polyurethane resin. More specifically, it relates to a composition for a thermoplastic polyurethane resin having particularly excellent solubility, a thermoplastic polyurethane resin obtained by hot molding using the composition, and a molded article.

[0002]

2. Description of the Related Art Thermoplastic polyurethane resins are excellent in various properties such as rubber elasticity, abrasion resistance, chemical resistance, and cold resistance, and molded articles can be easily obtained by molding ordinary thermoplastic resins. It is a material with excellent workability that can do things.
For example, Japanese Examined Patent Publication No. 62-40363 discloses an NCO group-terminated prepolymer obtained by reacting a poly (oxypropylene-oxyethylene) diol with an aromatic diisocyanate (4,4'-diphenylmethane diisocyanate). And obtaining a thermoplastic polyether polyurethane elastomer. Also, JP
JP-A-95119 describes a thermoplastic polyurethane resin using paraphenylene diisocyanate, a polyol and a chain extender. Furthermore, JP-A-6-1021
All of the techniques of 1, Japanese Patent Publication No. 1-34539, Japanese Patent Publication No. 64-8746, and Japanese Patent Publication No. 60-43445 add a polyisocyanate compound having an isocyanate group at the molecular end to a molten thermoplastic polyurethane resin. A method is known in which a cross-linking structure such as an allophanate bond is formed between molecules forming a linear thermoplastic polyurethane resin to obtain a thermoplastic polyurethane resin having performance close to that of a thermosetting polyurethane resin. Most of the organic diisocyanate components constituting the conventional thermoplastic polyurethane resin are 4,4'-diphenylmethane diisocyanate, which is one of the easy-to-handle isocyanates. Most of the properties of the thermoplastic polyurethane resin composed of 4,4′-diphenylmethane diisocyanate depend on the properties of the long-chain polyol, and the commercially available thermoplastic polyurethane resin has a hardness (HsA) of 80- 98.

[0003]

However, the thermoplastic polyurethane resin obtained by the conventionally known technique has excellent physical properties such as rubber elasticity, abrasion resistance, chemical resistance, and cold resistance, but is soluble in a solvent. Was inferior.
The inventors of the present invention have conducted extensive research and study on thermoplastic polyurethane resins having excellent physical properties and excellent solubility, and as a result, as an isocyanate compound, a specific diphenylmethane-based diisocyanate and a specific proportion of a long-chain polyol and a chain extension have been obtained. It has been found that the object is achieved by using the agent, and the present invention has been completed.

[0004]

That is, the present invention provides a thermoplastic polyurethane resin composition comprising (A) an isocyanate compound and (B) a long-chain polyol, wherein the (A) isocyanate compound is a diphenylmethane diisocyanate, and 50-98% by weight of 4'-diphenylmethane diisocyanate, 50-98% by weight of isomers other than 4,4'-
2% by weight, the hydroxyl value of the long-chain polyol (B) is 50 to 150 KOHmg / g, and the molar ratio of isocyanate group (A) / active hydrogen group (B) is 0.85 to 1.1.
It is a composition for thermoplastic polyurethane resin having excellent solubility, which is characterized by being 5.

The present invention provides (A) an isocyanate compound,
In a thermoplastic polyurethane resin composition comprising (B) a long-chain polyol and (C) a chain extender, the (A) isocyanate compound is a diphenylmethane-based diisocyanate, which is 4,4′-diphenylmethane diisocyanate.
0 to 98% by weight and 50 to 2% by weight of isomers other than 4,4'-, and the (B) / (C) molar ratio of the (B) long-chain polyol and the (C) chain extender is 0.1 to 18, (B)
The hydroxyl value of the mixture obtained by mixing the long-chain polyol and the (C) chain extender is 10 to 150 KOHmg / g, and the molar ratio of the isocyanate group (A) / active hydrogen group (B) and (C) is 0. It is a composition for thermoplastic polyurethane resin having excellent solubility characterized by being 85 to 1.15.

The present invention is a method for producing a thermoplastic polyurethane resin having excellent solubility, which comprises reacting and pelletizing the above composition for thermoplastic polyurethane resin.

The present invention is a molded product characterized by hot molding the composition for thermoplastic polyurethane resin or thermoplastic polyurethane resin.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The (A) isocyanate compound constituting the composition for thermoplastic polyurethane resin of the present invention includes diphenylmethane diisocyanate (hereinafter referred to as MD).
Abbreviated as I) type diisocyanate. The MDI diisocyanate comprises 4,4'-MDI in the range of 50 to 98% by weight and MDI other than 4,4'-in 50 to 2% by weight, preferably 4,4'-MDI in the range of 50 to 90%. weight%
And 50 to 10% by weight of 2,2'- and 2,4'-MDI
It is. More preferably 4,4'-MDI is 71-86
Wt% and 2,2'- and 2,4'-MDI 29-14
% By weight. Of these, 2,2'-MDI and 2,4'-
The weight ratio of MDI is 2,9'-90% by weight of 2,4'-MDI to 0.5-10% by weight of 2,2'-MDI.
It is. In this case 2,2'- and 2,4'-MDI are 2
If it is less than 5% by weight, the solubility in a solvent becomes poor.

Further, the (A) isocyanate compound includes
Other polyisocyanates can be used in combination. For example, phenylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,4-naphthylene diisocyanate, 1,5-naphthylene diisocyanate, 4,4'-diphenyl ether diisocyanate, 2-nitrodiphenyl-4 ，
4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,
Aromatic polyisocyanates such as 4'-diphenylpropane diisocyanate, isophorone diisocyanate,
Aliphatic diisocyanates such as tetramethylene diisocyanate and hexamethylene diisocyanate, hydrogenated T
Alicyclic diisocyanates such as DI and hydrogenated MDI; These can be used alone or as a mixture of two or more kinds.

Examples of the long-chain polyol (B) constituting the composition for thermoplastic polyurethane resin of the present invention include ester-based, ether-based, lactone-based and carbonate-based polyols. Their molecular weight is 500 to 10
000, preferably 850-5000. Examples of the ester-based polyol include ethylene glycol, propylene glycol, 1,4-butanediol,
1,3-butanediol, 1,4-butenediol,
1,3-butenediol, 1,6-hexanediol,
Polyhydric alcohols such as 3-methyl 1,5-pentanediol, neopentyl glycol and 1,5-pentanediol, and fatty acids such as adipic acid, sebacic acid, azelaic acid, terephthalic acid, isophthalic acid and maleic acid, Or the polyester diol etc. which are obtained from aromatic carboxylic acid are mentioned. Examples of ether-based polyols include polyalkylene ether diols such as polyethylene glycol, polypropylene ether glycol, polytetramethylene ether glycol, and polyhexamethylene ether glycol. Examples of the lactone-based polyol include polycaprolactone glycol, polypropiolactone glycol, and polyvalerolactone glycol. Examples of the carbonate-based polyol include ethylene glycol, propylene glycol, 1,4-butanediol,
1,3-butanediol, 1,5-pentanediol,
Methylpentanediol, methyloctanediol,
Polycarbonate diols obtained by dealcoholation reaction of polyhydric alcohols such as 1,9-nonanediol with diethylene carbonate, dipropylene carbonate and the like can be mentioned. Particularly preferred polyols are polyester polyols and polyether polyols.

Examples of the (C) chain extender constituting the composition for thermoplastic polyurethane resin of the present invention include ethylene glycol, polypropylene glycol, 1,4-butanediol, 1,3-butanediol and 1,6-. Hexanediol, 3-methyl-1,5-pentanediol,
1,4-bis (β-hydroxyethoxy) benzene, neopentyl glycol, methyloctanediol, 1,
9-nonanediol, bisphenol, dimethylolpropane, polypropylene glycol and the like can be mentioned.
The hydroxyl value when the (B) long chain polyol of the present invention is used alone is 50 to 150 KOHmg / g, and when the (B) long chain polyol and the (C) chain extender are used, ) And (C) are used at a molar ratio of (B) / (C) of 0.1.
-18, and preferably the molar ratio of (B) / (C) is 0.1-70. The hydroxyl value of the mixture obtained by mixing the (B) long-chain polyol and the (C) chain extender is 10 to 150.
KOHmg / g, more preferably 10 to 130 KOHmg / g
It is.

As a method for synthesizing a thermoplastic polyurethane resin using the composition for thermoplastic polyurethane resin of the present invention, a known synthesis method can be used. Examples thereof include a continuous synthesis method using an extruder and a batch synthesis method having a kneading tank such as a kneader.

Various additives can be added to the composition for thermoplastic polyurethane resin of the present invention and the polyurethane resin using the composition. As the additive, for example,
Dyes and pigments for the purpose of coloring molded products, inorganic fillers such as glass fibers for the purpose of improving the shape retention and bending strength of the molded products, lubricants for the purpose of improving releasability during injection molding, etc. A flame retardant improver, an antistatic agent, an antifungal agent, etc. can be used.

The hot molding method using the composition for thermoplastic polyurethane resin of the present invention is a molding method using an injection molding machine or an extrusion molding machine for molding a usual thermoplastic resin. The following items are listed. In injection molding, there are many relatively complicated molded products, and examples thereof include various machine parts, various automobile parts, and various electromechanical parts. In extrusion molding, there are many relatively simple long molded products, and examples thereof include belts, sheets, films, hoses, tubes and the like. Further, as an application of extrusion molding, an ultrathin film obtained by blow molding and the like can be mentioned. In particular, the thermoplastic polyurethane resin of the present invention includes acetone, methyl ethyl ketone (hereinafter abbreviated as MEK), methylene chloride (hereinafter abbreviated as methylo), cyclohexanone (hereinafter abbreviated as anone), dimethylformamide (hereinafter abbreviated as DMF). ) Has good solubility in all solvents, and the solution can be used as various coating agents.

[0015]

Industrial Applicability The composition for thermoplastic polyurethane resin having excellent solubility provided by the present invention, and the method for producing a resin and the molded product using the composition are the same as those of the conventional 4,4'-
Compared with polyurethane resin molded products composed of MDI, it has excellent solubility, and can be easily molded and processed by injection molding machines and extrusion molding machines that mold and process ordinary thermoplastic resins. It has solubility without impairing properties such as mechanical strength and chemical resistance, and its solution is excellent in adhesiveness to various base materials and coating properties and can be used in various fields.

[0016]

EXAMPLES The present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples. In Examples and Comparative Examples, “parts” and “%” mean “parts by weight” and “% by weight”, respectively.

The raw materials used in the present invention are shown below. MDI (1): 2,2'-MDI 1.8%, 2,4'-MDI 27.0%, 4,4'-MDI 71.2% MDI (2): 2,2'-MDI 0. 9%, 2,4'-MDI 15.8%, 4,4'-MDI 83.3% MDI (3): 2,2'-MDI 0.1%, 2,4'-MDI 1.7% , 4,4'-MDI 98.2% 1,4-BD: 1,4-butanediol BHEB: 1,4-bis (β-hydroxyethoxy) benzene, Mitsui Oil & Chemicals PBA-1000: polybutylene Adipate glycol (number average molecular weight 1000, manufactured by Nippon Polyurethane Industry) PBA-2000: polybutylene adipate glycol (number average molecular weight 2000, manufactured by Nippon Polyurethane Industry)

Example 1 [Composition for thermoplastic polyurethane resin] (B) PBA-
A thermoplastic polyurethane resin composition comprising 800 parts of 1000 and 200 parts of (A) MDI (1) was obtained. Production of thermoplastic polyurethane resin 800 parts of PBA-1000 was charged into the kneader system (B
The hydroxyl value of the mixture of C and C is 112 KOHmg / g, (B) /
(The molar ratio of (C) is 0), and after the temperature inside the system is adjusted to 70 ° C., 200 parts of MDI (1) (NCO / OH =
(1.0) was made into a resin and then self-pulverized to produce a thermoplastic polyurethane resin. (Production of molded product) This thermoplastic polyurethane resin is used for extruder cylinder temperature 150 ° C, adapter temperature 160
C., the belt die temperature was adjusted to 170.degree. C., and strand pellets were obtained at a screw rotation speed of 40 rpm. The appearance was clear thermoplastic polyurethane resin pellets. This was used for the solubility test. The results are shown in Table 1. Next, the thermoplastic polyurethane resin pellets were prepared by an injection molding machine at a cylinder temperature of 160 ° C. and a nozzle temperature of 180 ° C. to prepare a 120 mm × 120 mm, 2 mm thick flat plate for physical property testing. Hardness (HsA) is 56, 100%
Modulus is 20 (Kgf / cm ² ), 300% modulus is 5
The tensile strength was 6 (Kgf / cm ² ), the tensile strength was 340 (Kgf / cm ² ), and the elongation was 630%.

Example 2 Production of Thermoplastic Polyurethane Resin 750 parts of PBA-750 having a hydroxyl value of 150 KOHm
g / g, (B) / (C) molar ratio is 0, MDI (2) 25
A thermoplastic polyurethane resin was produced in the same manner as in Example 1, except that 0 part (this NCO / OH = 1.0) was used. (Production of Molded Article) In the same manner as in Example 1, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. The results are shown in Table 1. Next, a thermoplastic polyurethane resin pellet was prepared by an injection molding machine in the same manner as in Example 1 to prepare a flat plate for measuring physical properties. The hardness (HsA) was 63.

Example 3 [Composition for thermoplastic polyurethane resin] (B) PBA-
1000 for 750 parts, 1,4-BG for 13.5 parts,
(A) A composition for thermoplastic polyurethane resin consisting of 236 parts of MDI (1) was obtained. Production of thermoplastic polyurethane resin 750 parts of PBA-1000 and 13.5 of 1,4-BD
Part The hydroxyl value of this mixture is 132 KOHmg / g, (B) /
A thermoplastic polyurethane resin was produced in the same manner as in Example 1 except that the molar ratio of (C) was 0.2 and 236 parts of MDI (1) (this NCO / OH = 1.05). (Production of Molded Article) In the same manner as in Example 1, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. The results are shown in Table 1. Next, a thermoplastic polyurethane resin pellet was prepared by an injection molding machine in the same manner as in Example 1 to prepare a flat plate for measuring physical properties. The hardness (HsA) was 60.

Example 4 Production of Thermoplastic Polyurethane Resin 750 parts of PBA-1000 and 13.5 of 1,4-BD.
Part The hydroxyl value of this mixture is 132 KOHmg / g, (B) /
A thermoplastic polyurethane resin was produced in the same manner as in Example 1 except that (C) had a molar ratio of 0.2 and 236 parts of MDI (2) (this NCO / OH = 1.05). (Production of Molded Article) In the same manner as in Example 1, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. The results are shown in Table 1. Next, a thermoplastic polyurethane resin pellet was prepared by an injection molding machine in the same manner as in Example 1 to prepare a flat plate for measuring physical properties. The hardness (HsA) was 58.

Example 5 Preparation of thermoplastic polyurethane resin 699 parts of PBA-2000 and 56.7 of 1,4-BD.
Part The hydroxyl value of this mixture is 145 KOHmg / g, (B) /
A thermoplastic polyurethane resin was produced in the same manner as in Example 1 except that the molar ratio of (C) was 1.8 and 245 parts of MDI (1) (this NCO / OH = 1.00) was used. (Production of molded article) This thermoplastic polyurethane resin is used for extruder cylinder temperature 160 ° C, adapter temperature 170
C. and the belt die temperature was adjusted to 180.degree. C., and strand pellets were obtained at a screw rotation speed of 40 rpm. The appearance was clear thermoplastic polyurethane resin pellets. This was used for the solubility test. The results are shown in Table 1. Next, the thermoplastic polyurethane resin pellets were prepared by an injection molding machine at a cylinder temperature of 170 ° C. and a nozzle temperature of 185 ° C. to prepare a 120 mm × 120 mm, 2 mm thick flat plate for physical property testing. The hardness (HsA) was 70.

Example 6 Preparation of thermoplastic polyurethane resin 699 parts of PBA-2000 and 56.7 of 1,4-BD.
Part The hydroxyl value of this mixture is 145 KOHmg / g, (B) /
A thermoplastic polyurethane resin was produced in the same manner as in Example 1 except that the molar ratio of (C) was 1.8 and 245 parts of MDI (2) (this NCO / OH = 1.00). (Production of Molded Article) This thermoplastic polyurethane resin was obtained in the same manner as in Example 5 to obtain thermoplastic polyurethane resin pellets. This was used for the solubility test. The results are shown in Table 1. Next, a thermoplastic polyurethane resin pellet was prepared by an injection molding machine in the same manner as in Example 5 to form a flat plate for measuring physical properties. The hardness (HsA) was 68.

Example 7 Preparation of Thermoplastic Polyurethane Resin 751 parts of PBA-1000 and 59.6 parts of BHEB The hydroxyl value of this mixture is 146 KOHmg / g, (B) / (C).
Has a molar ratio of 0.4, MDI (1) 189 parts (this NCO
/OH=1.00) in the same manner as in Example 1 to produce a thermoplastic polyurethane resin. (Production of Molded Article) In the same manner as in Example 5, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. The results are shown in Table 1. Next, a thermoplastic polyurethane resin pellet was prepared by an injection molding machine in the same manner as in Example 5 to form a flat plate for measuring physical properties. The hardness (HsA) was 74.

Example 8 Preparation of thermoplastic polyurethane resin 751 parts of PBA-1000 and 59.6 parts of BHEB The hydroxyl value of this mixture is 146 KOHmg / g, (B) / (C).
Has a molar ratio of 0.4, MDI (2) 189 parts (this NCO
/OH=1.00) in the same manner as in Example 1 to produce a thermoplastic polyurethane resin. (Production of Molded Article) In the same manner as in Example 5, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. The results are shown in Table 1. Next, a thermoplastic polyurethane resin pellet was prepared by an injection molding machine in the same manner as in Example 5 to form a flat plate for measuring physical properties. The hardness (HsA) was 72.

Example 9 Production of Thermoplastic Polyurethane Resin 651 parts of PBA-2000 and 129 parts of BHEB The hydroxyl value of this mixture is 140 KOHmg / g, the molar ratio of (B) / (C) is 2.0, and MDI ( 1) 220 parts (this NCO /
OH = 0.90) and a thermoplastic polyurethane resin was produced in the same manner as in Example 1. (Production of Molded Article) In the same manner as in Example 5, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. The results are shown in Table 1. Next, a thermoplastic polyurethane resin pellet was prepared by an injection molding machine in the same manner as in Example 5 to form a flat plate for measuring physical properties. The hardness (HsA) was 73.

Example 10 Production of thermoplastic polyurethane resin PBA-2000 651 parts, BHEB 129 parts This mixture has a hydroxyl value of 140 KOHmg / g, a (B) / (C) molar ratio of 2.0, and an MDI ( 2) 220 parts (this NCO /
OH = 0.90) and a thermoplastic polyurethane resin was produced in the same manner as in Example 1. (Production of Molded Article) In the same manner as in Example 5, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. The results are shown in Table 1. Next, a thermoplastic polyurethane resin pellet was prepared by an injection molding machine in the same manner as in Example 5 to form a flat plate for measuring physical properties. The hardness (HsA) was 71.

Comparative Example 1 Preparation of Thermoplastic Polyurethane Resin 750 parts of PBA-1000 having a hydroxyl value of 150 KO
Hmg / g, (B) / (C) molar ratio is 0, MDI (3) 2
A thermoplastic polyurethane resin was produced in the same manner as in Example 1 with 50 parts (this NCO / OH = 1.00). (Production of molded article) This thermoplastic polyurethane resin is used for extruder cylinder temperature 175 ° C, adapter temperature 185
C., the temperature of the belt die was adjusted to 195.degree. C., and strand pellets were obtained at a screw rotation speed of 40 rpm. Thermoplastic polyurethane resin pellets were obtained in the same manner as in Example 1. This was used for the solubility test. Table 2 shows the results. Next, the thermoplastic polyurethane resin pellets were made into a flat plate for measuring physical properties by the same method as in Example 1 using an injection molding machine. The hardness (HsA) was 84.

Comparative Example 2 Production of Thermoplastic Polyurethane Resin 750 parts of PBA-1000 and 13.5 of 1,4-BD.
Part The hydroxyl value of this mixture is 132 KOHmg / g, (B) /
A thermoplastic polyurethane resin was produced in the same manner as in Example 1 except that the molar ratio of (C) was 0.2 and 236 parts of MDI (3) (this NCO / OH = 1.05). (Production of Molded Article) By the same method as in Comparative Example 1, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. Table 2 shows the results. Next, a thermoplastic polyurethane resin pellet was used to prepare a flat plate for measuring physical properties in the same manner as in Comparative Example 1 using an injection molding machine. The hardness (HsA) is
78.

Comparative Example 3 Preparation of Thermoplastic Polyurethane Resin 699 parts of PBA-2000 and 56.7 of 1,4-BD.
Part The hydroxyl value of this mixture is 145 KOHmg / g, (B) /
A thermoplastic polyurethane resin was produced in the same manner as in Example 1 except that (C) had a molar ratio of 1.8 and 245 parts of MDI (3) (this NCO / OH = 1.00). (Production of Molded Article) By the same method as in Comparative Example 1, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. Table 2 shows the results. Next, a thermoplastic polyurethane resin pellet was used to prepare a flat plate for measuring physical properties in the same manner as in Comparative Example 1 using an injection molding machine. The hardness (HsA) is
83.

Comparative Example 4 Production of Thermoplastic Polyurethane Resin 751 parts of PBA-1000 and 59.6 parts of BHEB The hydroxyl value of this mixture is 146 KOHmg / g, (B) / (C).
Has a molar ratio of 0.4, MDI (3) 189 parts (this NCO
/OH=1.00) in the same manner as in Example 1 to produce a thermoplastic polyurethane resin. (Production of Molded Article) By the same method as in Comparative Example 1, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. Table 2 shows the results. Next, a thermoplastic polyurethane resin pellet was used to prepare a flat plate for measuring physical properties in the same manner as in Comparative Example 1 using an injection molding machine. The hardness (HsA) is
It was 87.

Comparative Example 5 Production of Thermoplastic Polyurethane Resin 651 parts of PBA-2000 and 129 parts of BHEB The hydroxyl value of this mixture is 140 KOHmg / g, the molar ratio of (B) / (C) is 0.9, and MDI ( 3) 220 parts (this NCO /
OH = 0.90) and a thermoplastic polyurethane resin was produced in the same manner as in Example 1. (Production of Molded Article) In the same manner as in Example 1, thermoplastic polyurethane resin pellets were obtained. This was used for the solubility test. Table 2 shows the results. Next, a thermoplastic polyurethane resin pellet was used to prepare a flat plate for measuring physical properties in the same manner as in Comparative Example 1 using an injection molding machine. The hardness (HsA) is
It was 84.

Solubility Test The pellets of Examples 1-10 and Comparative Examples 1-5 were tested. 80 parts of each solvent shown in Tables 1 and 2 was added to 20 parts of the pellet, and the mixture was stirred and dissolved at 40 ° C. for 180 minutes. Evaluation method ○: Complete dissolution △: Gel-like dissolution ×; Swelling (insoluble)

[0034]

[Table 1]

[0035]

[Table 2]

Physical Properties Measurement Hardness, 100% modulus, 300% modulus, tensile strength, elongation, etc. were measured according to JIS-K-7331.

Claims (4)

[Claims] 1. An isocyanate compound (A) and (B)
In a composition for a thermoplastic polyurethane resin comprising a long-chain polyol, the (A) isocyanate compound is a diphenylmethane diisocyanate containing 4,4′-diphenylmethane diisocyanate in an amount of 50 to 98% by weight and 4,4 ′.
50% to 2% by weight of isomers other than-, the hydroxyl value of the long-chain polyol (B) is 50 to 150 KOHmg / g, and the molar ratio of isocyanate group (A) / active hydrogen group (B) is 0. The composition for thermoplastic polyurethane resin having excellent solubility, which is 85 to 1.15. 2. A thermoplastic polyurethane resin composition comprising (A) an isocyanate compound, (B) a long-chain polyol and (C) a chain extender, wherein the (A) isocyanate compound is a diphenylmethane-based diisocyanate.
50 'to 4'-diphenylmethane diisocyanate
%, And isomers other than 4,4′-comprising 50 to 2% by weight, and the (B) / (C) molar ratio of the (B) long-chain polyol and the (C) chain extender is 0.1. The hydroxyl value of the mixture obtained by mixing (B) the long chain polyol and (C) the chain extender is 10 to 150 KOHmg / g, and the isocyanate group (A) / active hydrogen group (B) and (C) ,
The composition for thermoplastic polyurethane resin having excellent solubility, characterized in that the molar ratio thereof is 0.85 to 1.15. 3. A method for producing a thermoplastic polyurethane resin having excellent solubility, which comprises reacting and pelletizing the composition for thermoplastic polyurethane resin according to claim 1. 4. A molded product obtained by hot molding the composition for thermoplastic polyurethane resin according to claim 1 or 2, or the thermoplastic polyurethane resin according to claim 3.