JP2016113529A - Method for producing acyclic alkylene polycarbonate diol - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an acyclic alkylene polycarbonate diol having a carbonate bond and an ester bond, and a method for producing the same.SOLUTION: A method for producing an acyclic alkylene polycarbonate diol is characterized by the reaction between a polycarbonate diol and a cyclic ester compound, the acyclic alkylene polycarbonate diol having a repeating unit represented by formula (A) and a repeating unit represented by formula (B) and also having hydroxy groups at both terminals of a molecule (Z is a C2-12 straight/branched alkylene group).SELECTED DRAWING: None

Description

  The present invention relates to a method for producing an acyclic alkylene polycarbonate diol.

Conventionally, as a method for producing a polycarbonate diol having both a carbonate bond (carbonate skeleton) and an ester bond (ester skeleton), for example, the following method has been disclosed.
(1) Polyester polycarbonate diol (lactone-modified polycarbonate diol) is disclosed by reacting a polycarbonate diol based on cyclohexanedimethanol with a lactone (see, for example, Patent Document 1).
(2) There is a general description that a polyester polycarbonate diol as a polyurethane production raw material can be produced by reacting a lactone with a polycarbonate diol (for example, see Patent Document 2).
(3) A method of reacting polycarbonate diol, caprolactone and alkylene oxide (initiator) is disclosed (for example, see Patent Document 3).
(4) A method for producing a polyester polycarbonate diol by reacting a polycarbonate diol and a lactone, which discloses that the polycarbonate skeleton in the obtained compound is 30 to 70% by mass (for example, Patent Documents) 4).
(5) A method of reacting a polycarbonate diol with a large excess of lactone in the presence of a special amine is disclosed (for example, see Patent Document 5).
(6) A method of reacting polycarbonate diol with 5-200% caprolactone is disclosed (for example, see Patent Document 6).

JP 2013-216841 A JP 2012-184385 A International Publication No. 2005/116102 JP-A-11-001549 JP-A-8-059800 JP-A-2-014273

  However, Patent Document 1 only describes a polycarbonate diol having a cyclic alkylene group, and the polycarbonate diol in which an ester bond is introduced into a polycarbonate diol having an acyclic alkylene group, which is extremely versatile. There was no disclosure. In addition, there was no description of the difference in effect due to the difference in ester skeleton content (ratio where lactone was introduced).

  Patent Document 2 only describes a general method, and does not describe any difference in effect due to a difference in ester skeleton content (ratio in which lactone is introduced).

  In Patent Document 3, the ratio between the polycarbonate diol and the lactone is not limited at all, and the use ratio between the alkylene oxide and the lactone is only defined.

  In Patent Document 4, the weight of the polycarbonate skeleton (unit) is specified. However, since this is 23 to 75 mol% in terms of mole, the ester skeleton (lactone content) exceeds 0 mol% and exceeds 23 mol%. Less than, exceeding 75 mol% and less than 100 mol%, is clearly different from the range in which the effect is exhibited in the present invention.

  In Patent Document 5, a compound having a very high lactone ester content is obtained by using a large excess of lactone with respect to polycarbonate diol, but no specific ratio is described.

In Patent Document 6, the use ratio of polycarbonate diol and lactone is widely described as 5 to 200%, and there is no description that the effect is exerted in a specific range. In the examples, since the amount used is 33% by weight, the lactone skeleton weight is 26.4% by weight, and the molar ratio is about 25% by mole. Therefore, the effective range is different from that of the present invention. .

  As described above, in any of the methods, there is only a specific disclosure of a reaction between a polycarbonate diol composed of 1,6-hexanediol and ε-caprolactone (in Patent Document 1, a polycarbonate diol containing a cyclic alkylene group). In addition, there was no description that the molar ratio of the ester skeleton derived from the lactone had an effect within a specific range.

  Therefore, an acyclic alkylene polycarbonate diol having an ester skeleton derived from a specific lactone and having excellent handling properties such as a low melting point and a low viscosity has been desired.

  The subject of this invention is providing the acyclic alkylene polycarbonate diol which has a carbonate bond and an ester bond, and its manufacturing method.

  The subject of this invention is Formula (1).

(In the formula, n represents the number of repeating units.)
A polycarbonate diol represented by formula (2)

(In the formula, Z represents a linear or branched alkylene group having 2 to 12 carbon atoms.)
Characterized by reacting with a cyclic ester compound represented by:
Formula (A)

A repeating unit represented by formula (B)

(In the formula, Z represents a linear or branched alkylene group having 2 to 12 carbon atoms.)
And a method for producing an acyclic alkylene polycarbonate diol having a hydroxyl group at each of both ends of the molecule.
However, the number of repeating units represented by the formula (B) relative to the total number of repeating units of the acyclic alkylene polycarbonate diol (the number of repeating units represented by the formula (B) / [the number of repeating units represented by the formula (A) + formula (B )] Is 0.30 to 0.70.

  According to the present invention, an acyclic alkylene polycarbonate diol having excellent handling properties can be obtained. The acyclic alkylene polycarbonate diol of the present invention is a useful compound as a raw material for producing polyurethane resins and the like.

  In the present invention, the acyclic alkylene polycarbonate diol has the formula (1)

(In the formula, n represents the number of repeating units.)
A polycarbonate diol represented by formula (2)

(In the formula, Z represents a linear or branched alkylene group having 2 to 12 carbon atoms.)
By reacting with a cyclic ester compound represented by
Formula (A)

A repeating unit represented by formula (B)

(In the formula, Z represents a linear or branched alkylene group having 2 to 12 carbon atoms.)
And a cyclic alkylene polycarbonate diol having a hydroxyl group at each of both ends of the molecule (hereinafter also referred to as “reaction of the present invention”).
However, the number of repeating units represented by the formula (B) relative to the total number of repeating units of the acyclic alkylene polycarbonate diol (the number of repeating units represented by the formula (B) / [the number of repeating units represented by the formula (A) + formula (B )] Is 0.30 to 0.70.

(Polycarbonate diol)
The polycarbonate diol used in the reaction of the present invention is represented by the above formula (1). In the formula (1), n represents the number of repeating units. The polycarbonate diol can be obtained by reacting a carbonate or phosgene with a diol. By using a plant-derived diol, a polycarbonate diol having a high plant-derived component content can be obtained.

In the reaction of the present invention, an acyclic alkylene polycarbonate diol having a high plant-derived component content can be produced by using a polycarbonate diol having a high plant-derived component content.
In this way, by including plant-derived components at a high ratio, the so-called carbon neutral environment can be used even if carbon dioxide discharged by incineration and carbon dioxide absorbed in the process of plant growth do not become the same amount. Can be a friendly process.

(Cyclic ester compound)
The cyclic ester compound used in the reaction of the present invention is represented by the above formula (2). In the formula (2), Z is a linear or branched alkylene group having 2 to 12 carbon atoms. Specifically, for example, ethylene group (dimethylene group), propylene group (trimethylene group), butylene Group (tetramethylene group), pentylene group (pentamethylene group), hexylene group (hexamethylene group), heptamethylene group, octamethylene group, nonamethylene group, decamethylene group, undecamethylene group, dodecamethylene group, etc. , Preferably propylene group (trimethylene group), butylene group (tetramethylene group), pentylene group (pentamethylene group), more preferably propylene group (trimethylene group), butylene group (tetramethylene group), particularly preferably It is a butylene group (tetramethylene group).

  Specific examples of the cyclic ester compound include four-membered cyclic ester compounds such as β-propiolactone and β-butyrolactone; and five-membered cyclic ester compounds such as γ-butyrolactone and γ-valerolactone. A six-membered cyclic ester compound such as δ-valerolactone; and a seven-membered cyclic ester compound such as ε-caprolactone, preferably γ-butyrolactone, γ-valerolactone, δ-valerolactone, ε- Caprolactone, more preferably γ-valerolactone, δ-valerolactone, particularly preferably δ-valerolactone is used.

In addition, the non-cyclic alkylene polycarbonate diol with a high plant-derived component content rate can be manufactured by using a cyclic ester compound with a high plant-derived component content rate as these cyclic ester compounds.
As a plant-derived cyclic ester compound, for example, δ-valerolactone can be produced using furfural, furfuryl alcohol, tetrahydrofurfuryl alcohol, or the like as a raw material.
In this way, by including plant-derived components at a high ratio, the so-called carbon neutral environment can be used even if carbon dioxide discharged by incineration and carbon dioxide absorbed in the process of plant growth do not become the same amount. Can be a friendly process.

  The amount of the cyclic ester compound used in the reaction of the present invention is preferably 0.45 to 5.0 mol, more preferably 0.50 to 4. mol, based on 1 mol of the 1,6-hexanediol skeleton of the polycarbonate diol. 5 mol, more preferably 0.55 to 4.0, particularly preferably 0.60 to 3.5.

(1,6-hexanediol)
In the reaction of the present invention, 1,6-hexanediol may be present to adjust the product to a desired molecular weight, and the amount is preferably 0 to 1 mol of lactone added. 0.5 mol, more preferably 0.01 to 0.2 mol.
In addition, a non-cyclic alkylene polycarbonate diol with a high plant-derived component content can be produced by using 1,6-hexanediol having a high plant-derived component content as these 1,6-hexanediols.

(catalyst)
The reaction of the present invention is promoted by performing it in the presence of a catalyst. As such a catalyst, those generally known as transesterification catalysts can be used, but preferably,
Metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, magnesium hydroxide, calcium hydroxide;
Metal carbonates such as lithium carbonate, sodium carbonate, potassium carbonate, magnesium carbonate, calcium carbonate;
Metal hydrogen carbonates such as lithium hydrogen carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate;
Metal carboxylates such as lithium acetate, sodium acetate, potassium acetate, magnesium acetate, calcium acetate, zinc acetate, manganese acetate, nickel acetate, antimony acetate;
Lithium methoxide, sodium methoxide, sodium ethoxide, potassium ethoxide, potassium t-butoxide, magnesium methoxide, calcium methoxide, calcium ethoxide, aluminum ethoxide, aluminum isopropoxide, aluminum sec-butoxide, zirconium isopropoxide , Zirconium t-butoxide, titanium tetraethoxide, titanium tetraisopropoxide, titanium tetra n-butoxide, titanium tetra t-butoxide, titanium tetracyclohexyl alkoxide, titanium tetrabenzyl alkoxide, triisopropoxy titanium stearate, tributoxy titanium Metal alkoxides such as stearate and antimony tripentoxide;
Metal diketonates such as aluminum acetylacetonate, zinc acetylacetonate, zirconium acetylacetonate, diisopropoxytitanium bisacetylacetonate, dihydroxytitanium lactate;
Examples include alkyl metals such as dibutyltin oxide, dibutyltin diacetate, and dibutyltin dilaurate.
Preferably, titanium tetraethoxide, titanium tetraisopropoxide, titanium tetra n-butoxide, titanium tetra t-butoxide, titanium tetracyclohexyl alkoxide, titanium tetrabenzyl alkoxide, triisopropoxy titanium stearate, tributoxy titanium stearate, dibutyl tin Oxide, dibutyltin diacetate, dibutyltin dilaurate,
More preferably, titanium tetraethoxide, titanium tetraisopropoxide, titanium tetra n-butoxide, titanium tetra t-butoxide is used.
In addition, you may use these catalysts individually or in mixture of multiple types. Moreover, when the said catalyst is contained in polycarbonate diol, this may be used for reaction of this invention as it is, and a deficiency may be supplemented separately.

  The amount of the catalyst used is preferably 1 to 10000 μg, more preferably 10 to 1000 μg, based on 1 g of the raw material polycarbonate diol.

  The reaction of the present invention is performed, for example, by a method of mixing polycarbonate diol, a cyclic ester compound, 1,6-hexanediol and a catalyst and reacting them while stirring. The reaction temperature in that case becomes like this. Preferably it is 100-300 degreeC, More preferably, it is 150-250 degreeC, Reaction pressure is 1-1000 kPa, More preferably, it is 3-150 kPa.

  After completion of the reaction, the acyclic alkylene polycarbonate diol of the present invention can be obtained, for example, by removing unreacted raw materials from the reaction solution under reduced pressure. When a catalyst is used for the reaction, it is desirable to add a catalyst deactivator (for example, phosphate ester in the case of titanium alkoxide) after completion of the reaction.

The reaction of the present invention can be carried out in the presence or absence of a catalyst other than the above-described method,
“Method of mixing and reacting carbonate ester, diol compound, polylactone diol (ring-opening polymerization product of cyclic ester compound) and / or cyclic ester compound”,
"Method of mixing and reacting polylactone diol (ring-opening polymer of cyclic ester compound) and polycarbonate diol"
Can also be obtained.

(Acyclic alkylene polycarbonate diol)
The acyclic alkylene polycarbonate diol of the present invention is represented by the formula (A)

A repeating unit represented by formula (B)

(In the formula, Z represents a linear or branched alkylene group having 2 to 12 carbon atoms.)
And an acyclic alkylene polycarbonate diol having one hydroxyl group at each end of the molecule.
However, the number of repeating units represented by the formula (B) relative to the total number of repeating units of the acyclic alkylene polycarbonate diol (the number of repeating units represented by the formula (B) / [the number of repeating units represented by the formula (A) + formula (B )] Is 0.30 to 0.70, more preferably 0.35 to 0.70.

Preferred embodiments of the acyclic alkylene polycarbonate diol of the present invention are as follows.
Number average molecular weight; 500 or more melting point; 10 ° C. or less glass transition point; −60 ° C. or less viscosity; 1,100 cp or less (75 ° C.)

Further preferred embodiments of the acyclic alkylene polycarbonate diol of the present invention are as follows.
Number average molecular weight: 500-2,100
Melting point: -15 ° C to 10 ° C
Glass transition point: -80 ° C to -60 ° C
Viscosity: 50 to 1,100 cp (75 ° C.)

In addition, by using a cyclic ester compound having a high plant-derived component content as the polycarbonate diol and the cyclic ester compound, an acyclic alkylene polycarbonate diol having an extremely high plant-derived component content can be produced.
In this way, by including plant-derived components at a high ratio, the so-called carbon neutral environment can be used even if carbon dioxide discharged by incineration and carbon dioxide absorbed in the process of plant growth do not become the same amount. Can be a friendly process.

Next, the present invention will be specifically described with reference to examples, but the scope of the present invention is not limited thereto.
(Various analysis methods)
(1) Hydroxyl value: Measured according to JIS K 1557 method B.
(2) Acid value: Measured according to the indicator titration method of JIS K 1557.
(3) Moisture: Measured by a coulometric titration method using a Karl Fischer moisture meter.
(4) Melting point and glass transition temperature: differential scanning calorimetry (measurement temperature range: −100 ° C. to 10 ° C.
0 ° C., scanning speed: 10 ° C./min. ).
(5) Viscosity: measured at 75 ° C. using a B-type viscometer.
(6) Number average molecular weight: Calculated based on the hydroxyl value.
(7) Number of repeating units of formula (A) and number of repeating units of formula (B); measured by ¹ H-NMR.
(material)
The polycarbonate diol used in the examples is ETERNACOLL (registered trademark) UH-200N manufactured by Ube Industries, Ltd. (number average molecular weight is 2000, hydroxyl value is 56.0 mgKOH / g, acid value is 0.02 mgKOH / g, tetrabutoxy) Titanium catalyst was contained at 100 ppm).

Example 1 (Synthesis of acyclic alkylene polycarbonate diol)
Into a 200 mL internal volume glass flask equipped with a stirrer and a thermometer, 111.7 g of polycarbonate diol (55.85 mmol; 785 mmol as 1,6-diol skeleton) and 5.3 g of 1,6-hexanediol (45 Mmol) and dried under reduced pressure for 1 hour with stirring.
To the obtained solution, 85.1 g (850 mmol) of δ-valerolactone was added and reacted for 1 hour at 75 to 85 ° C. with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of the reaction, the reaction solution was cooled to room temperature to obtain 175 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.38
Number average molecular weight; 2010 g / mol hydroxyl value; 55.9 mg KOH / g
Acid value: 0.08 mgKOH / g
Melting point: -7 ° C
Viscosity: 1068 cp (75 ° C.)
Glass transition point: -61 ° C
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was within the scope of the present invention, the melting point was low.

Comparative Example 1 (Synthesis of acyclic alkylene polycarbonate diol)
In a 200 mL internal volume glass flask equipped with a stirrer and a thermometer, 151.1 g of polycarbonate diol (76 mmol; 1061 mmol as 1,6-hexanediol skeleton) and 3.0 g of 1,6-hexanediol (26 mmol) ) And dried under reduced pressure with stirring.
To the obtained solution, 46.6 g (466 mmol) of δ-valerolactone was added and reacted at 190 to 195 ° C. for 4 hours with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of the reaction, the reaction solution was cooled to room temperature to obtain 200.7 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.28
Number average molecular weight; 1930 g / mol hydroxyl value; 58.1 mg KOH / g
Acid value: 0.01 mg KOH / g
Melting point: 13 ° C
Viscosity: 1161 cp (75 ° C.)
Glass transition point: -66 ° C
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was less than 0.30 (outside the scope of the present invention), the melting point was high.

Example 2 (Synthesis of acyclic alkylene polycarbonate diol)
In a 200 mL internal volume glass flask equipped with a stirrer and a thermometer, 130.93 g of polycarbonate diol (65 mmol; 920 mmol as 1,6-hexanediol skeleton) and 4.13 g of 1,6-hexanediol (35 mmol) ) And dried under reduced pressure with stirring.
To the obtained solution, 63.70 g (636 mmol) of δ-valerolactone was added and reacted at 190 to 195 ° C. for 4 hours with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of the reaction, the reaction solution was cooled to room temperature to obtain 198.76 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.38
Number average molecular weight; 1910 g / mol hydroxyl value; 58.8 mg KOH / g
Acid value: 0 mgKOH / g
Melting point: -8 ° C
Viscosity: 885 cp (75 ° C.)
Glass transition point: -68 ° C
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was within the scope of the present invention, the melting point was low.

Example 3 (Synthesis of acyclic alkylene polycarbonate diol)
In a 200 mL glass flask equipped with a stirrer and a thermometer, 111.7 g of polycarbonate diol (56 mmol; 785 mmol as 1,6-hexanediol skeleton) and 5.3 g of 1,6-hexanediol (45 mmol) ) And dried under reduced pressure with stirring.
To the obtained solution, 85.1 g (850 mmol) of δ-valerolactone was added and reacted for 4 hours at 175 to 180 ° C. with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of the reaction, the reaction solution was cooled to room temperature to obtain 175.1 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.48
Number average molecular weight; 2010 g / mol hydroxyl value; 55.9 mg KOH / g
Acid value: 0.08 mgKOH / g
Melting point: -7 ° C
Viscosity: 1068 cp (75 ° C.)
Glass transition point: -61 ° C
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was within the scope of the present invention, the melting point was low.

Example 4 (Synthesis of acyclic alkylene polycarbonate diol)
In a 100 mL glass flask equipped with a stirrer and a thermometer, 45.07 g of polycarbonate diol (23 mmol; 317 mmol as 1,6-hexanediol skeleton) and 3.28 g of 1,6-hexanediol (28 mmol) ) And dried under reduced pressure with stirring.
To the obtained solution, 51.71 g (516 mmol) of δ-valerolactone was added and reacted at 190 to 195 ° C. with stirring for 4 hours (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of the reaction, the reaction solution was cooled to room temperature to obtain 98.79 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.58
Number average molecular weight; 1990 g / mol hydroxyl value; 56.3 mg KOH / g
Acid value: 0.22 mg KOH / g
Melting point: -7 ° C
Viscosity: 556 cp (75 ° C.)
Glass transition point: -72 ° C
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was within the scope of the present invention, the melting point was low.

Example 5 (Synthesis of acyclic alkylene polycarbonate diol)
Into a 200 mL internal volume glass flask equipped with a stirrer and a thermometer, 100.7 g of polycarbonate diol (50 mmol; 708 mmol as 1,6-hexanediol skeleton) and 18.4 g of 1,6-hexanediol (156 mmol) ) And dried under reduced pressure with stirring.
To the obtained solution, 86.4 g (863 mmol) of δ-valerolactone was added and reacted for 4 hours at 190 to 195 ° C. with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of stirring, the reaction solution was cooled to room temperature to obtain 205.5 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.48
Number average molecular weight; 1000 g / mol hydroxyl value; 112.4 mg KOH / g
Acid value: 0.01 mg KOH / g
Melting point: -14 ° C
Viscosity: 172 cp (75 ° C.)
Glass transition point: -77 ° C
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was within the scope of the present invention, the melting point was low.

Example 6 (Synthesis of acyclic alkylene polycarbonate diol)
In a 200 mL glass flask equipped with a stirrer and a thermometer, 38.1 g of polycarbonate diol (19 mmol; 268 mmol as 1,6-hexanediol skeleton) and 9.6 g of 1,6-hexanediol (81 mmol) ) And dried under reduced pressure with stirring.
To the obtained solution, 52.4 g (523 mmol) of δ-valerolactone was added and reacted for 4 hours at 190 to 195 ° C. with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of the stirring, the reaction solution was cooled to room temperature to obtain 100.1 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.60
Number average molecular weight; 1240 g / mol hydroxyl value; 90.5 mg KOH / g
Acid value: 0.001 mg KOH / g
Melting point: -10 ° C
Viscosity: 144 cp (75 ° C.)
Glass transition point: -78 ° C
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was within the scope of the present invention, the melting point was low.

Example 7 (Synthesis of acyclic alkylene polycarbonate diol)
In a 200 mL internal volume glass flask equipped with a stirrer and a thermometer, 26.3 g of polycarbonate diol (13 mmol; 185 mmol as 1,6-hexanediol skeleton) and 10.3 g of 1,6-hexanediol (87 mmol) ) And dried under reduced pressure with stirring.
63.5 g (634 mmol) of δ-valerolactone was added to the obtained solution, and reacted for 4 hours at 190 to 195 ° C. with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of stirring, the reaction solution was cooled to room temperature to obtain 0.0 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.69
Number average molecular weight: 1110 g / mol hydroxyl value: 100.8 mg KOH / g
Acid value: 0.02 mg KOH / g
Melting point: -3 ° C
Viscosity: 105 cp (75 ° C.)
Glass transition point: -78 ° C
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was within the scope of the present invention, the melting point was low.

Comparative Example 2 (Synthesis of acyclic alkylene polycarbonate diol)
A glass flask having an internal volume of 200 mL equipped with a stirrer and a thermometer was charged with 30.95 g of polycarbonate diol (15 mmol; 217 mmol as a 1,6-hexanediol skeleton) and 7.10 g of 1,6-hexanediol (60 mmol). ) And dried under reduced pressure with stirring.
111.73 g (1116 mmol) of δ-valerolactone was added to the obtained solution and reacted for 4 hours at 190 to 195 ° C. with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of the stirring, the reaction solution was cooled to room temperature to obtain 149.61 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol was a novel compound represented by the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.81
Number average molecular weight; 1890 g / mol hydroxyl value; 59.4 mg KOH / g
Acid value: 3.84 mg KOH / g
Melting point: 36 ° C
Viscosity: 420 cp (75 ° C.)
Glass transition point: -65 ° C
Since the number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] exceeded 0.65 (out of the scope of the present invention), the melting point was high.

Reference Example 1 (polycarbonate diol having no ester bond)
Polycarbonate diol produced from 1,6-hexanediol and carbonic acid diester (ETERNACOLL (registered trademark) UH-200N manufactured by Ube Industries, Ltd .; 1,6-hexanediol: carbonic acid diester = 1: 1 (molar ratio)) The physical properties were measured and found to be as follows.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0
Melting point: 49 ° C
Viscosity: 2245cp (75 ° C)
Glass transition point: -56 ° C

Reference Example 2 (Synthesis of acyclic alkylene polycarbonate diol)
Into a glass flask having an internal volume of 200 mL equipped with a stirrer and a thermometer, 100.7 g of polycarbonate diol (50 mmol; 708 mmol as 1,6-hexanediol skeleton) and 5.5 g of 1,6-hexanediol (46 mmol) ) And dried under reduced pressure with stirring.
To the obtained solution, 87.2 g (764 mmol) of ε-caprolactone was added and reacted for 4 hours at 185 to 195 ° C. with stirring (the titanium compound contained in the polycarbonate diol acts as a catalyst).
After completion of the stirring, the reaction solution was cooled to room temperature to obtain 193.3 g of an acyclic alkylene polycarbonate diol.

The obtained acyclic alkylene polycarbonate diol has the following physical property values.
Number of repeating units of formula (B) / [number of repeating units of formula (A) + number of repeating units of formula (B)] = 0.51
Number average molecular weight; 2130 g / mol hydroxyl value; 52.6 mg KOH / g
Acid value: 0.02 mg KOH / g
Melting point: 15 ° C
Viscosity: 1044 cp (75 ° C.)
Since the number of repeating units of formula (B) / [the number of repeating units of formula (A) + the number of repeating units of formula (B)] was within the scope of the present invention, the melting point was lower than that of the polycarbonate diol of Reference Example 1.

  The results are summarized in Table 1.

  From the above results, it was found that low melting point, low viscosity and low glass transition point can be achieved by introducing an ester group into polycarbonate diol.

  According to the present invention, an acyclic alkylene polycarbonate diol having excellent handling properties can be obtained. The acyclic alkylene polycarbonate diol of the present invention is a useful compound as a raw material for producing polyurethane resins and the like.

Claims (7)

Formula (1)

(In the formula, n represents the number of repeating units.)
A polycarbonate diol represented by formula (2)

(In the formula, Z represents a linear or branched alkylene group having 2 to 12 carbon atoms.)
Characterized by reacting with a cyclic ester compound represented by:
Formula (A)

A repeating unit represented by formula (B)

(In the formula, Z represents a linear or branched alkylene group having 2 to 12 carbon atoms.)
And a method for producing an acyclic alkylene polycarbonate diol having a hydroxyl group at each of both ends of the molecule.
However, the number of repeating units represented by the formula (B) relative to the total number of repeating units of the acyclic alkylene polycarbonate diol (the number of repeating units represented by the formula (B) / [the number of repeating units represented by the formula (A) + formula (B )] Is 0.30 to 0.70.   The method for producing an acyclic alkylene polycarbonate diol according to claim 1, wherein the amount of the cyclic ester compound used is 0.45 to 5.0 mol as 1 mol of 1,6-hexanediol skeleton of the polycarbonate diol. The manufacturing method of the acyclic alkylene polycarbonate diol of Claim 1 whose acyclic alkylene polycarbonate diol is shown by the following physical-property values.
Number average molecular weight; 500 or more melting point; 10 ° C. or less glass transition point; −60 ° C. or less viscosity; 1,100 cp or less (75 ° C.)   The method for producing an acyclic alkylene polycarbonate diol according to any one of claims 1 to 3, wherein Z is a butylene group. Formula (A)

A repeating unit represented by formula (B)

(In the formula, Z represents a linear or branched alkylene group having 2 to 12 carbon atoms.)
An acyclic alkylene polycarbonate diol having a repeating unit represented by the formula (1) and having hydroxyl groups at both ends of the molecule.
However, the number of repeating units represented by the formula (B) relative to the total number of repeating units of the acyclic alkylene polycarbonate diol (the number of repeating units represented by the formula (B) / [the number of repeating units represented by the formula (A) + formula (B )] Is 0.30 to 0.70. The acyclic alkylene polycarbonate diol according to claim 5, wherein the acyclic alkylene polycarbonate diol is represented by the following physical property values.
Number average molecular weight; 500 or more melting point; 10 ° C. or less glass transition point; −60 ° C. or less viscosity; 1,100 cp or less (75 ° C.)   The acyclic alkylene polycarbonate diol according to any one of claims 5 to 6, wherein Z is a butylene group.