JP2003113237A - Polycarbonate and method for producing polyurethane using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polycarbonate capable of producing a product having excellent low-temperature properties when used for applications such as paints, adhesives, polyurethanes and polyamide elastomers. SOLUTION: The following formula (1): -OR ¹ -OR ² -O-CO- (1) (wherein, R ¹ and R ² may have a branch. Represented by an alkylene group having 3 to 20 carbon atoms, a cycloalkylene group or an arylene group) in an amount of 5 mol% or more, and having a number average molecular weight of 300 to 30,
000.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel polycarbonate, and more specifically to a paint, an adhesive, a synthetic leather,
TECHNICAL FIELD The present invention relates to a polycarbonate suitable for applications such as artificial leather, urethane acrylate, polyurethane and polyamide elastomer, and a method for producing polyurethane using the same.

[0002]

2. Description of the Related Art Conventionally, polycarbonates having a hydroxyl group at the molecular end have been used in the fields of paints, adhesives, polyurethanes and the like. Examples of such polycarbonates include 3-methyl-1,5-pentanediol and 1,6-
Polycarbonates obtained from polyhydric alcohols such as hexanediol and carbonic acid diesters or phosgene are known (Japanese Patent Application Laid-Open No. 3-281517, Patent No. 30).
45787, etc.). Among these polycarbonates, polycarbonate having a hydroxyl group at the terminal,
Polyurethane can be obtained by reacting with a bifunctional or higher functional isocyanate compound to produce an elastomer,
It is used in a wide range of applications such as paints, adhesives, coating agents and foams.

[0003]

However, although the conventional polycarbonate having a hydroxyl group at the molecular end and the polyurethane using the same are excellent in hydrolysis resistance, they are generally known to have a high glass transition temperature.
Therefore, since products obtained from these conventional polycarbonates are often used in combination with polyethers having a low glass transition temperature when used at low temperatures,
In general, there is a problem that the weather resistance is poor and it is easily deteriorated by heat or light.

Further, in order to lower the glass transition temperature of polycarbonate and polyurethane obtained therefrom,
It is useful to use a long-chain diol such as 1,9-nonanediol as the monomer diol, but even in this case, it is difficult to say that the improvement effect thereof sufficiently satisfies the market demand.

The object of the present invention is therefore to produce polycarbonates having a low glass transition temperature, which have excellent low-temperature properties when used in applications such as paints, adhesives, polyurethanes and polyamide elastomers. An object of the present invention is to provide a possible novel polycarbonate, and to provide a method for producing a polyurethane excellent in low-temperature properties using the same.

[0006]

As a result of intensive studies on the above problems, the present inventors have found that a polycarbonate having a specific structure can be obtained and can be solved by using this as a raw material for polyurethane, and completed the present invention.

That is, the present invention is A) The following formula (1)

[0008]

## STR2 ## ^{-O-R 1 -O-R 2} -O-CO- (1) ( wherein, ^{R 1} and ^{R 2} is an alkylene group having 3 to 20 carbon atoms which may have a branched, cyclo Represents an alkylene group or an arylene group, respectively)

A polycarbonate containing 5 mol% or more of the repeating unit represented by and having a number average molecular weight of 300 to 30,000. Further, the present invention is B) the polycarbonate described in A) above, wherein R ¹ and R ² are both butylene groups. Furthermore, the present invention provides C) as another polyfunctional alcohol component, 2-methyl-
1,3-propanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-methyl-
A) containing 5 to 95 mol% of at least one diol unit selected from 1,8-octanediol and 3-methyl-1,7-octanediol.
Or the polycarbonate described in B).

The present invention also provides: D) a method of reacting a high molecular weight polyol, a polyisocyanate and a chain extender to produce polyurethane, wherein the polycarbonate according to any one of A) to C) is used as a polyol component, A method for producing a polyurethane, characterized in that a diisocyanate compound is used as a polyisocyanate component, and a low-molecular weight compound having at least two active hydrogen atoms mainly composed of an aliphatic diol having 2 to 20 carbon atoms is used as a chain extender component. is there.
Furthermore, the present invention is E) a polyurethane obtained by the method described in D) above.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The polycarbonate of the present invention has the following formula (1):

[0012]

Embedded image —O—R ¹ —O—R ² —O—CO— (1) (In the formula, R ¹ and R ² are optionally branched C 3-20 alkylene groups, cyclo Represents an alkylene group or an arylene group, respectively)

It is necessary that the content of the repeating unit represented by the formula is 5 mol% or more and the number average molecular weight is 300 to 30,000. In the above formula (1), R ¹ and R
² represents an alkylene group having 3 to 20 carbon atoms which may have a branch, a cycloalkylene group or an arylene group, and examples of the alkylene group having 3 to 20 carbon atoms include, for example, a propylene group, a butylene group and a pentane group. Examples thereof include methylene, hexamethylene group, heptamethylene group, octamethylene group, and the like. Examples of the cycloalkylene group include:
1,4-cyclohexylene group and the like, examples of the arylene group, for example, 1,2-phenylene group, 1,3-
Examples thereof include a phenylene group and a 1,4-phenylene group.
These groups may have a branch (substituent). Among these, it is preferable that both R ¹ and R ² are alkylene groups having 3 to 9 carbon atoms, and it is particularly preferable that both R ¹ and R ² are butylene groups.

The polycarbonate of the present invention can be produced, for example, from a diol having an ether bond represented by the following formula (2) and a carbonic acid diester or phosgene represented by the formula (3).

[0015]

Embedded image HO—R ¹ —O—R ² —OH (2) (wherein R ¹ and R ² are as defined above).

[0016]

Embedded image wherein R ³ —O—CO—O—R ⁴ (3) (wherein R ³ and R ⁴ represent an alkyl group, a cycloalkyl group or an aryl group, respectively, or R ³ and R ⁴ are Together, it represents a divalent saturated hydrocarbon group which may contain an oxygen atom in the carbon chain.)

In the above formula (3), R ³ and R ⁴
Represents an alkyl group, a cycloalkyl group or an aryl group, respectively, or represents a divalent saturated hydrocarbon group in which R ³ and R ⁴ are united to each other and may contain an oxygen atom in the carbon chain. As the alkyl group, for example,
Examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group.Examples of the cycloalkyl group include a 1,4-cyclohexyl group and the like, and an aryl group. Is, for example, 1,2-phenyl group, 1,3-phenyl group, 1,4
A phenyl group and the like. These groups may have a branch (substituent).

The polycarbonate provided by the present invention is composed of the repeating unit represented by the above formula (1), and a specific example of the diol represented by the above formula (2), which is one component constituting the repeating unit, is shown. And an ether diol which is a combination of various diols. Examples of the diol constituting the ether diol include propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol and 2,2-diethyl-diol.
1,3-propanediol, 2-butyl-2-ethyl-
1,3-propanediol, 1,3-butanediol,
1,4-butanediol, 2-methyl-1,4-butanediol, 1,5-pentanediol, 3-methyl-
1,5-pentanediol, 1,6-hexanediol, 2-methyl-1,8-octanediol, 2,7-
Dimethyl-1,8-octanediol, 1,9-nonanediol, 2-methyl-1,9-nonanediol, 2,
Aliphatic diols such as 8-dimethyl-1,9-nonanediol and 1,10-decanediol; 1,4-cyclohexanediol, cyclohexanedimethanol, 3,8-
Dihydroxytricyclo (5.2.1.0 ^2,6 ) decane, 4,9-dihydroxytricyclo (5.2.1.0)
Examples of the alicyclic diol include ^2,6 ) decane, and the target ether diol can be obtained from one or two diols selected from these. Among these,
Ether diols composed of aliphatic diols are preferable, and 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,9-nonanediol, 2-methyl-1,3-propanediol, A dimer ether diol such as 3-methyl-1,5-pentanediol is more preferable, and a dimer ether diol of 1,4-butanediol is particularly preferable.

Examples of the carbonic acid diester represented by the above formula (3) include dimethyl carbonate, diethyl carbonate,
Examples thereof include ethylene carbonate and diphenyl carbonate. These may be used alone or in combination of two or more. Also, phosgene can be used instead of the carbonic acid diester.

The polycarbonate of the present invention must contain the repeating unit represented by the above formula (1) in an amount of 5 mol% or more, preferably 10 mol% or more. When the content of the repeating unit represented by the above formula (1) is less than 5 mol%, the effect of improving the low temperature properties of the obtained polycarbonate may not be sufficiently exhibited, which is not preferable.

The polycarbonate of the present invention may contain units derived from other polyols in addition to the units derived from the diol represented by the above formula (2). Examples of units of such other polyols include ethylene glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,3-butylene glycol, 1.4-butanediol, and 2 -Methyl-1,4-butanediol, 1,5-
Pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 2-methyl-1,8
-Octanediol, 2,7-dimethyl-1,8-octanediol, 1,9-nonanediol, 2-methyl-
1,9-nonanediol, 2,8-dimethyl-1,9-
Nonanediol, 1,10-decanediol, 2,2-
Diethyl-1,3-propanediol, 2-butyl-2
Units derived from aliphatic diols such as ethyl-1,3-propanediol; 1,4-cyclohexanediol, cyclohexanedimethanol, 3,8-dihydroxytricyclo (5.2.1.0 ^2,6 ). Decane 4,9
Units derived from alicyclic diols such as dihydroxytricyclo (5.2.1.0 ^2,6 ) decane; trimethylolpropane, 1,4-bis (β-hydroxyethoxy) benzene, bis (β- Units derived from aromatic ring-containing diols such as hydroxyethoxy) terephthalate;
Trimethylolethane, trimethylolpropane, glycerin, 1,2,6-hexanetriol, 1,2,4
-Units derived from trifunctional or higher functional polyols such as butanetriol, units derived from carboxyl group-containing polyols such as dimethylolpropionic acid, and the like. Among these, units derived from an aliphatic diol are preferable, and 2-methyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 1,9-
A unit derived from at least one diol selected from nonanediol, 2-methyl-1,8-octanediol, 3-methyl-1,7-octanediol and the like is more preferable. The unit derived from the above diol is 5 to 95 mol% in the polycarbonate, preferably 10 to 9
It is desirable to contain 0 mol%.

Further, the polycarbonate of the present invention is required to have a number average molecular weight of 300 to 30,000, as described above, and it is preferably in the range of 700 to 20,000. The number average molecular weight of polycarbonate is 3
If the number average molecular weight of the polycarbonate is more than 30,000, the mechanical properties such as strength and flexibility of the polyurethane obtained from the polycarbonate become poor. It is not preferable because the characteristics are poor.

When the polycarbonate of the present invention is used, for example, in the production of polyurethane, it is necessary to use one having a hydroxyl group at the molecular end. The terminal structure of the polycarbonate can be appropriately adjusted by changing the charged molar ratio of the polyol component as a raw material and the carbonic acid diester or phosgene component. The optimum number of hydroxyl groups present in the polycarbonate varies depending on the application, but if the number of hydroxyl groups is generally 2 or more per molecule, and especially within the range of 2 to 3, the polycarbonate is used for many applications. Is possible,
It becomes versatile.

The method for producing the polycarbonate of the present invention is not particularly limited, and a conventionally known method for producing a polycarbonate can be applied. For example, 1,4-
4,4'-Dihydroxydibutyl ether, which is a dimer of butanediol, and carbonic acid diester or phosgene are charged at a predetermined ratio, a condensation reaction is performed, and the obtained reaction product is heated at high temperature in vacuum in the presence of a polycondensation catalyst. Further, a polycondensation reaction can be carried out to produce a polycarbonate having a desired molecular weight. A wide variety of polycondensation catalysts can be used, and examples thereof include titanium compounds such as tetramethoxy titanium, tetraethoxy titanium, tetra-n-propoxy titanium, tetraisopropoxy titanium, and tetrabutoxy titanium; di-n-butyltin oxide. , Tin compounds such as di-n-butyltin dilaurate and butyltin diacetate; and combinations of acetate salts such as magnesium, calcium and zinc with antimony oxide or the above titanium compounds. These polycondensation catalysts are usually used in the range of 5 to 500 ppm based on the total polycarbonate produced.

The polycarbonate of the present invention has a low glass transition temperature, and when used as a raw material for producing paints, adhesives, polyurethanes, etc., it is possible to obtain products having excellent low-temperature properties. Further, the polycarbonate of the present invention is applicable not only to the above-mentioned raw materials for production but also to various other uses.

As the method for producing the polyurethane of the present invention, for example, in the method of producing a polyurethane by reacting a polymer polyol, a polyisocyanate and a chain extender, the polycarbonate of the present invention is used as a polyol component and a polyisocyanate component is used. As the chain extender component, a diisocyanate compound is used as the component, and a low-molecular compound having at least two active hydrogen atoms mainly containing an aliphatic diol having 2 to 20 carbon atoms is used.

In the method for producing polyurethane of the present invention, the following formula (1) is used.

[0028]

Embedded image —O—R ¹ —O—R ² —O—CO— (1) (In the formula, R ¹ and R ² are optionally branched C 3-20 alkylene groups, cyclo Represents an alkylene group or an arylene group, respectively)

The above-mentioned polycarbonate containing 5 mol% or more of the repeating unit represented by and having a number average molecular weight of 300 to 30,000 is used.
In addition to the polycarbonate, other polyols such as polyester polyol, polyether polyol, and polycarbonate polyol can be added. These other polyols are usually used in the range of 40% by mass or less, more preferably 20% by mass or less, based on the total polyol components.

The polyisocyanate component used in the method of the present invention is not particularly limited, and diisocyanate compounds conventionally used in the production of polyurethane can be used. Examples of the diisocyanate compound include 4,4′-diphenylmethane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, 1,5-naphthylene diisocyanate, 3,3′-dichloro-4,4′-diphenylmethane diisocyanate, xylylene diisocyanate, Aromatic diisocyanates such as toluylene diisocyanate;
Aliphatic or alicyclic diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate and the like can be mentioned. These diisocyanate compounds may be used alone or in combination of two or more. In addition, in the method of the present invention, if necessary, triisocyanate or the like 3
It is also possible to use polyisocyanates that are functional or higher. In this case, thermosetting polyurethane is usually formed.

Further, in the method of the present invention, a low molecular weight compound having at least two active hydrogen atoms mainly composed of an aliphatic diol having 2 to 20 carbon atoms as a chain extender (hereinafter, simply referred to as "having an active hydrogen atom"). Sometimes referred to as "low molecular weight compound"). Specific examples of the low molecular weight compound having at least two active hydrogen atoms include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and , 8-Octanediol, 1,9-nonanediol, xylylene glycol, bishydroxybenzene, neopentyl glycol, 3,3-dichloro-4,4'-diaminophenylmethane, isophoronediamine, 4,4'-diaminodiphenylmethane , Hydrazine, dihydrazide, trimethylolpropane, glycerin and the like. These low molecular weight compounds may be used alone or in combination of two or more. The amount of the chain extender used is not particularly limited and may be appropriately selected depending on the hardness to be imparted to the target polyurethane, but is usually in the range of 10 mol or less per mol of the polycarbonate diol, and 0.2 It is desirable to be in the range of ˜6 mol.

Further, in the method of the present invention, any of catalysts, reaction accelerators, foaming agents, internal release agents, fillers, reinforcing agents, face dyes, stabilizers and the like which are commonly used in the production of polyurethanes can be used. Can be used as needed.

In the method of the present invention, when a polyol component, a polyisocyanate component and a chain extender component are reacted to produce a polyurethane, the diisocyanate compound which is the polyisocyanate component is the polycarbonate diol of the present invention which is the polyol component, For the total amount of active hydrogen atoms possessed by the low molecular weight compound having active hydrogen atoms which is the chain extender component and other components,
It is preferable to use it in such a ratio that the number of moles of the isocyanate group per 1 mol of the active hydrogen atom is 0.9 to 1.5 mol, and it is more preferable to use such a ratio that it is about 1 mol.

As the method for producing the polyurethane in the present invention, any known urethanization reaction technique can be used, and examples thereof include a prepolymer method and a one-shot method. As a specific example of the method for producing polyurethane, (a) a polycarbonate diol and a low molecular weight compound having an active hydrogen atom are mixed and heated to 40 to 100 ° C.,
After adding a diisocyanate compound in an amount such that the molar ratio of active hydrogen atoms and isocyanate groups in the mixture is 1: 1 to 1: 1.5 to the obtained mixture and stirring for a short time, the mixture is heated to, for example, 50 to 160 ° C. A method for producing polyurethane by heating; (b) a method for producing polyurethane by kneading a mixture of a polycarbonate diol, a low molecular weight compound having an active hydrogen atom and a diisocyanate compound at a high temperature of 180 to 260 ° C .; A polycarbonate diol, a low molecular weight compound having an active hydrogen atom, a diisocyanate compound, etc. are continuously supplied to an extruder such as an axial screw type extruder,
For example, a method for producing polyurethane by continuous melt polymerization at a high temperature of 180 ° C. to 260 ° C .; (d) A method for carrying out a polyurethane forming reaction consisting of a polycarbonate diol, a low molecular weight compound having an active hydrogen atom and a diisocyanate compound in an organic solvent; And so on.

Among these methods, when the polyurethane is produced by the method (d), by controlling the concentrations of the polycarbonate diol, the low molecular weight compound having an active hydrogen atom and the diisocyanate compound, a high molecular weight polyurethane can be easily produced. can do. At this time, the concentrations of the polycarbonate diol, the low molecular weight compound having an active hydrogen atom and the diisocyanate compound are preferably in the range of 10 to 40 mass% with respect to the total amount of these and the organic solvent. As the organic solvent, dimethylformamide, dimethylacetamide, dimethylsulfoxide,
Tetrahydrofuran, toluene, methyl ethyl ketone,
Ethyl acetate, isopropanol, ethyl cellosolve and the like can be used. These organic solvents may be used alone or in combination of two or more.

The polyurethane obtained by the above-mentioned method of the present invention is excellent in hydrolysis resistance and is also excellent in balance of mechanical properties such as mechanical strength and flexibility.
Film, foam, roll, gear, solid tire,
Belts, hoses, tubes, packing materials, anti-vibration materials, shoe soles, sports shoes, machine parts, building materials, automobile parts,
It can be used in a wide range of applications such as furniture, linings, sealing materials, waterproof materials, sports goods, elastic fibers, artificial leather, fiber treatment agents, adhesives, coating agents, various binders, and paints.

[0037]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In addition, the number average molecular weight of polycarbonate and the evaluation of hydrolyzability in the following Examples and Comparative Examples were performed by the following methods. (Measurement of number average molecular weight) The hydroxyl value of the obtained polycarbonate was measured according to JIS K1557, and calculated based on the obtained value. (Measurement of glass transition temperature) Regarding the obtained polycarbonate and polyurethane, DSC (differential scanning calorimeter)
Was determined under a temperature rising condition of 10 ° C./min.

Example 1 175 g of diethyl carbonate and 151 g of 4,4'-dihydroxydibutyl ether, 73 g of 3-methyl-1,5-pentanediol and 40 of tetraisopropyl titanate.
mg was charged into a reactor, and the reaction was carried out while refluxing diethyl carbonate in a nitrogen atmosphere under normal pressure and distilling the produced ethanol together with diethyl carbonate out of the system. The temperature was gradually raised from the time when the amount of ethanol produced diminished, and the mixture was allowed to cool when the temperature reached 200 ° C. and the distillation of ethanol stopped. The pressure was reduced with a vacuum pump, and the excess diol component was distilled off while heating again to give a number average molecular weight of 2100.
Polycarbonate (hereinafter abbreviated as Polycarbonate A) was obtained. The glass transition temperature of Polycarbonate A was −60 ° C.

Example 2, Example 3 and Comparative Examples 1 to 3 Polycarbonates (polyesters) were prepared in the same manner as in Example 1 except that the diol and carbonic acid diester components shown in Table 1 were used in the molar ratios shown in Table 1. Hereinafter, the polycarbonates obtained in Examples 2 and 3 were referred to as polycarbonate B and polycarbonate C, and the polycarbonates obtained in Comparative Examples 1 to 3 were abbreviated as polycarbonate D to polycarbonate F). Polycarbonate B ~
The glass transition temperature of F is shown in Table 1.

[0040]

[Table 1]

In Table 1 above, the carbonic acid diester component and the diol component are indicated by the following abbreviations. DEC: diethyl carbonate (special grade of reagent) DHDBE: 4,4'-dihydroxydibutyl ether (4, obtained from tetrahydrofuran and acetic anhydride)
What was obtained by methanolysis of 4'-diacetoxy dibutyl ether was used. ) MPD: 3-methyl-1,5-pentanediol (manufactured by Kuraray) ND-65: 1,9-nonanediol (manufactured by Kuraray)
And ND-15 (manufactured by Kuraray Co.) mixed product (1,9-nonanediol / 2-methyl-1,8-octanediol is 6
5/35 (mass ratio)). DEG: Diethylene glycol (special grade reagent)

From Table 1, the glass transition temperature of the polycarbonate using DHDBE, which is a dimer ether diol composed of a diol having 4 carbon atoms, decreases with the amount of modification, but DEG which is a dimer ether diol composed of a diol having 2 carbon atoms. In the case of, it can be seen that the glass transition temperature rises due to denaturation. Furthermore, compared with the one modified with ND-65, which is a saturated hydrocarbon diol having 9 carbon atoms, the one modified with DHDBE is
It can also be seen that the effect of reducing the glass transition temperature is great.

Examples 4 to 6 and Comparative Examples 4 to 6 Polyurethanes were produced by the following method using each of the polycarbonates A to F obtained in Examples 1 to 3 and Comparative Examples 1 to 3. That is, each of the polycarbonate diols A to F is 0.05 mol (about 100 g; calculated from each molecular weight), 1,4-butanediol 0.10 mol (9
g), 0.15 mol (37.5 g) of 4,4′-diphenylmethane diisocyanate and 340 g of N, N′-dimethylformamide (abbreviated as DMF), and added at 80 ° C.
At room temperature for 6 to 8 hours to obtain a DMF solution of polyurethane (nonvolatile content 30%). DMF of the obtained polyurethane
The solution was cast on a glass plate and dried to obtain a dry film having a thickness of 100 μm. Using this film, the glass transition temperature was measured by the above method and used as an index of low temperature characteristics. The results obtained are shown in Table 2 below.

[0044]

[Table 2]

In Table 2 above, the polyurethane constituents are indicated by the following abbreviations. MDI: 4,4′-diphenylmethane diisocyanate (special grade reagent) BD: 1,4-butanediol (special grade reagent)

From Table 2 above, the glass transition temperature of the polyurethane obtained using DHDBE, which is a dimer ether diol consisting of a diol having 4 carbon atoms, decreases with the amount of modification, but the dimer consisting of a diol having 2 carbon atoms. In the case of DEG which is an ether diol, it can be seen that the glass transition temperature rises due to the modification. It can also be seen that the glass transition temperature-lowering effect is greater in the one modified with DHDBE than in the one modified with ND-65, which is a saturated hydrocarbon diol having 9 carbon atoms.

[0047]

Since the polycarbonate of the present invention has a low glass transition temperature, a product having excellent low-temperature properties can be obtained when it is used for applications such as paints, adhesives and polyurethanes. By carrying out the simple production method of the present invention using, it is possible to provide a polyurethane excellent in low-temperature characteristics.

Continued front page    F term (reference) 4J029 AA09 AB01 AD01 AD07 AE17                       BA02 BA04 BA05 BA07 BA08                       BA09 BA10 BB00 BB04A                       BB04B BB05A BB05B BD00                       BD03A BD04A BD07A BF00                       BF07 BF08 BF11 FC02 FC03                       FC05 HC01 HC04A HC05A                       JA091 JB131 JB161 JC751                       JF131 JF141 JF181 JF251                       JF371 JF471 KC01 KD02                       KD07 KE05 LA04 LB02                 4J034 BA08 CA04 CA05 CA15 CB03                       CC03 CC12 CC26 CC62 CC67                       CE03 DA01 DB03 DF01 DF02                       DF15 DF16 DG00 HA06 HA07                       HC02 HC12 HC13 HC22 HC61                       HC64 HC67 HC71 HC73 JA01                       JA02 JA06 JA14 JA32 JA38                       QA05 QB03 QB10 QB14 RA03                       RA07 RA08 RA10 RA11 RA12                       RA15

Claims (5)

[Claims] 1. The following formula (1): embedded image —O—R ¹ —O—R ² —O—CO— (1) (In the formula, R ¹ and R ² may have a branch. A good alkylene group having 3 to 20 carbon atoms, a cycloalkylene group or an arylene group, respectively) is contained in an amount of 5 mol% or more, and the number average molecular weight is 300 to 30,
Polycarbonate of 000. 2. The polycarbonate according to claim 1, wherein R ¹ and R ² are both butylene groups. 3. As another polyfunctional alcohol component, 2-methyl-1,3-propanediol, 3-methyl-1,5
-Pentanediol, 1,9-nonanediol, 2-methyl-1,8-octanediol, 3-methyl-1,7
Polycarbonate according to claim 1 or 2, characterized in that it contains at least 5 mol% of at least one diol unit selected from octanediol. 4. A method for producing a polyurethane by reacting a polymer polyol, a polyisocyanate and a chain extender, wherein the polycarbonate according to any one of claims 1 to 3 is used as a polyol component and a diisocyanate is used as a polyisocyanate component. A method for producing a polyurethane, wherein each of the compounds is a low molecular weight compound having at least two active hydrogen atoms mainly composed of an aliphatic diol having 2 to 20 carbon atoms as a chain extender component. 5. A polyurethane obtainable by the method of claim 4.