JP2022179709A - Polycarbonate polyol and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce high-quality polycarbonate diol with high productivity, which makes it possible to produce polyurethane having excellent flexibility, mechanical strength, solvent resistance and the like, using diethylene glycol as the raw material, by preventing the occurrence of dioxane, when producing polycarbonate diol by polycondensation of polyhydric alcohol containing diethylene glycol and carbonate compound.

SOLUTION: Polyhydric alcohol containing diol (A) and carbonate compound are subjected to polycondensation to produce polycarbonate diol with hydroxyl value of 20-450 mgKOH/g. The diol (A) contains oxyalkylene glycol (A1) represented by the formula (1) of 60 wt.% or more, and the oxyalkylene glycol (A1) contains diethylene glycol. The amount of dioxane occurring in the polycondensation step is controlled to 1.0 wt.% or less relative to the amount of diethylene glycol to be added.

SELECTED DRAWING: None

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present invention suppresses the generation of dioxane and uses oxyalkylene glycol as a raw material in the production of polycarbonate polyol by polycondensation of a polyhydric alcohol containing oxyalkylene glycol and a carbonate compound, thereby improving flexibility, mechanical strength, The present invention relates to an industrially advantageous method for producing a high-quality polycarbonate polyol capable of producing a polyurethane excellent in solvent resistance and the like. The present invention also relates to a high-quality polycarbonate polyol produced by suppressing generation of dioxane, and a method for producing polyurethane using this polycarbonate polyol.

Conventionally, it has been known to produce a polycarbonate diol-containing composition by polymerizing a dihydroxy compound and a carbonate compound by transesterification reaction. Examples of industrially produced polycarbonate diol-containing compositions include polycarbonate diol-containing compositions in which a dihydroxy compound such as 1,6-hexanediol is used as a raw material dihydroxy compound. , is generally used as a raw material for polyurethane and polyurethane acrylate.

Among the polycarbonate diols that are currently widely available on the market, polycarbonate diols synthesized from 1,6-hexanediol are highly crystalline. However, it has a problem of high cost and poor flexibility, elongation, bending or elastic recovery, especially at low temperatures, which limits its use. Furthermore, it has been pointed out that the artificial leather produced using the obtained polyurethane as a raw material has a hard texture and is inferior to natural leather in "feel".

In order to solve these problems, polycarbonate diols using oxyalkylene glycol as a raw material and having excellent flexibility and solvent resistance have been proposed. Patent Documents 1 and 2 describe polycarbonate diols using diethylene glycol. It is Further, Patent Document 3 describes a polycarbonate diol obtained by copolymerizing 1,6-hexanediol and triethylene glycol.

However, when a dihydroxy compound containing diethylene glycol is used as a raw material and a polycarbonate diol-containing composition is polymerized by transesterification, dioxane is produced as a by-product due to cyclodehydration of diethylene glycol and decarboxylation of terminal units of the obtained polycarbonate diol. live. There is a problem that the productivity of the polycarbonate diol-containing composition deteriorates as the amount of dioxane by-produced at this time increases. In addition, the dioxane produced as a by-product causes coloring of the polycarbonate diol product, and furthermore, the polycarbonate diol obtained in a reaction system in which a large amount of dioxane is produced as a by-product has the problem of being inferior in reactivity as a raw material for polyurethane. .

In addition, dioxane is designated as a specified chemical substance under the Industrial Safety and Health Act, and restrictions are imposed on its release into the atmosphere. However, in the industrial production of polycarbonate diols in which the reaction is carried out under high vacuum conditions, it is difficult to capture dioxane with a low boiling point in terms of equipment, and the by-product of dioxane is an important factor in improving the productivity of oxyalkylene glycol-derived polycarbonate diols. was a problem.

In addition, when dioxane remains in the polycarbonate diol-containing composition as a raw material when producing polyurethane or polyurethane acrylate, dioxane is also contained in the polyurethane solution used for paints and the like. There was also the issue of adverse health effects.

In order to avoid the problem of by-production of dioxane, methods for reducing the amount of dioxane produced as a by-product when producing a polymer using a dihydroxy compound capable of by-producing dioxane as a raw material have conventionally been investigated.

For example, Patent Document 4 describes a method for reducing the amount of dioxane generated by devising the conditions for charging monomers and the reaction temperature in a method for producing a polyester polyol using diethylene glycol as a raw material. However, Patent Document 4 relates to the production of a polyester polyol, and requires a higher reaction temperature, a higher vacuum condition, and a longer reaction time in order to remove a terminal structure such as a carbonate terminal derived from a raw material, which is a terminal structure that tends to remain. There is no description of an example of application to polycarbonate polyols in which it is difficult to achieve both suppression of the amount of generated and high-quality products.

Japanese Patent No. 5448627 Japanese Patent No. 5111159 Japanese Patent No. 3684567 Japanese translation of PCT publication No. 2012-529542

The present invention has been made in view of the above-mentioned conventional situation, and in the production of polycarbonate polyol by polycondensation of a polyhydric alcohol containing diethylene glycol and a carbonate compound, the generation of dioxane is suppressed and diethylene glycol is used as a raw material. Accordingly, an object of the present invention is to provide a highly productive method for producing a high-quality polycarbonate polyol capable of producing a polyurethane excellent in flexibility, mechanical strength, solvent resistance, and the like. Another object of the present invention is to provide a high-quality polycarbonate polyol produced while suppressing the generation of dioxane, and a process for producing polyurethane using this polycarbonate polyol.

As a result of repeated studies to solve the above problems, the present inventors have found that the amount of dioxane generated relative to the amount of diethylene glycol added in the polycondensation step using diethylene glycol as the polyhydric alcohol used as a raw material is controlled to a predetermined value or less. Thus, the inventors have found that the above problems can be solved.
That is, the gist of the present invention is as follows.

[1] A method for producing a polycarbonate polyol comprising a step of polycondensing a polyhydric alcohol and a carbonate compound, wherein the polycarbonate polyol has a hydroxyl value of 20 mgKOH/g or more and 450 mgKOH/g or less, and the polyhydric alcohol is A diol (A) is included, the diol (A) includes an oxyalkylene glycol (A1) represented by the following formula (1), and the content of the oxyalkylene glycol (A1) in the diol (A) is 60% by weight or more, the oxyalkylene glycol (A1) contains diethylene glycol, and the ends derived from the carbonate compound contained in the polycarbonate polyol are 1.0 mol% or less of all the ends, and in the polycondensation step A method for producing a polycarbonate polyol, wherein the amount of dioxane generated is controlled to 1.0% by weight or less with respect to the amount of diethylene glycol added.

(In formula (1), m represents an integer of 2 to 4, and R ^A represents a carbon chain having 2 to 5 carbon atoms and may contain a branch. m R ^A contained in formula (1) may be the same or different).

[2] The method for producing a polycarbonate polyol according to [1], wherein the carbonate compound is a diaryl carbonate.

[3] The method for producing a polycarbonate polyol according to [1] or [2], wherein a metal salt of Group 2 of the long-period periodic table is used as a catalyst in the polycondensation step.

[4] The method for producing a polycarbonate polyol according to any one of [1] to [3], wherein the reaction temperature in the polycondensation step is 150°C or higher and 180°C or lower.

[5] characterized by including a step of removing unreacted monomers of the polyhydric alcohol after the polycondensation step, and adding a phosphoric acid-based deactivator before the step of removing the unreacted monomers; , The method for producing a polycarbonate polyol according to any one of [1] to [4].

[6] The polyhydric alcohol further contains a trivalent to hexavalent branched alcohol (B) having 3 to 12 carbon atoms, and the structural unit derived from the branched alcohol (B) in the polycarbonate polyol is the 0.005 mol% or more and 5.0 mol% or less with respect to the total structural units derived from the polyhydric alcohol in the polycarbonate polyol, according to any one of [1] to [5] A method for producing a polycarbonate polyol.

[7] The polycarbonate polyol according to any one of [1] to [6], wherein the Hazen color number value (APHA value: according to JIS K0071-1 (1998)) is 50 or less. A method for producing a polycarbonate polyol.

[8] A method for producing polyurethane using a polycarbonate polyol produced by the method for producing a polycarbonate polyol according to any one of [1] to [7].

[9] A polycarbonate polyol which is a polycondensation reaction product of a polyhydric alcohol and a carbonate compound, having a hydroxyl value of 20 mgKOH/g or more and 450 mgKOH/g or less, and wherein one end derived from the carbonate compound is one of all the ends. .0 mol% or less, and the Hazen color number value (APHA value: according to JIS K0071-1 (1998)) is 50 or less, and the polyhydric alcohol is a diol (A) and a carbon number of 3 to 12 trihydric to hexahydric branched alcohol (B), the diol (A) contains an oxyalkylene glycol (A1) represented by the following formula (1), and in the diol (A) The content of the oxyalkylene glycol (A1) in is 60% by weight or more, and the oxyalkylene glycol (A1) contains diethylene glycol.

(In formula (1), m represents an integer of 2 to 4, and R ^A represents a carbon chain having 2 to 5 carbon atoms and may contain a branch. m R ^A contained in formula (1) may be the same or different).

[10] The structural unit derived from the branched alcohol (B) in the polycarbonate polyol is 0.005 mol% or more and 5.0 mol with respect to the total structural units derived from the polyhydric alcohol in the polycarbonate polyol. % or less, the polycarbonate polyol according to [9].

ADVANTAGE OF THE INVENTION According to this invention, the high quality polycarbonate polyol which uses xyalkylene glycol containing diethylene glycol as a raw material can be manufactured with sufficient productivity.
By polymerizing the polycarbonate polyol produced according to the present invention with isocyanate or the like, a polyurethane having high flexibility and mechanical strength and excellent solvent resistance can be provided. It also prevents the problem of volatilization of dioxane when using polyurethane.

Polyurethanes produced using the polycarbonate polyols of the present invention have good reactivity during urethane polymerization and an excellent balance of flexibility, mechanical strength and solvent resistance. It is suitable for leather, paint, high-performance elastomer applications, and is extremely useful in industry.

Although the present invention will be described in detail below, the present invention is not limited to the following description, and can be arbitrarily modified without departing from the gist of the present invention.
In this specification, when a numerical value or a physical property value is sandwiched before and after the "~", it is used to include the values before and after it. Further, in the present specification, "% by weight" and "% by weight", "ppm by weight" and "ppm by weight", and "parts by weight" and "parts by weight" are synonymous. Moreover, when simply described as "ppm", it indicates "weight ppm".

[1. Polycarbonate polyol and its manufacturing method]
A method for producing a polycarbonate polyol of the present invention is a method for producing a polycarbonate polyol comprising a step of polycondensing a polyhydric alcohol and a carbonate compound, wherein the hydroxyl value of the polycarbonate polyol is 20 mgKOH/g or more and 450 mgKOH/g or less. , the polyhydric alcohol contains a diol (A), the diol (A) contains an oxyalkylene glycol (A1) represented by the following formula (1), and the oxyalkylene glycol in the diol (A) The content of (A1) is 60% by weight or more, the oxyalkylene glycol (A1) contains diethylene glycol, and the ends derived from the carbonate compound contained in the polycarbonate polyol are 1.0 mol% or less of all the ends. The amount of dioxane generated in the polycondensation step is controlled to 1.0% by weight or less with respect to the amount of diethylene glycol added.

(In formula (1), m represents an integer of 2 to 4, and R ^A represents a carbon chain having 2 to 5 carbon atoms and may contain a branch. m R ^A contained in formula (1) may be the same or different).

Hereinafter, the amount of dioxane generated relative to the amount of oxyalkylene glycol (A1) added in the polycondensation step according to the present invention is simply referred to as "dioxane generated amount".

Further, the polycarbonate polyol of the present invention is a polycarbonate polyol which is a polycondensation reaction product of a polyhydric alcohol and a carbonate compound, has a hydroxyl value of 20 mgKOH/g or more and 450 mgKOH/g or less, and the end derived from the carbonate compound is , is 1.0 mol% or less in all terminals, and the value of Hazen color number (APHA value: in accordance with JIS K0071-1 (1998)) is 50 or less, and the polyhydric alcohol is a diol (A) and a trivalent to hexavalent branched alcohol (B) having 3 to 12 carbon atoms, wherein the diol (A) comprises an oxyalkylene glycol (A1) represented by the following formula (1), and The content of the oxyalkylene glycol (A1) in the diol (A) is 60% by weight or more, and the oxyalkylene glycol (A1) contains diethylene glycol.

Hereinafter, the terminal derived from the carbonate compound according to the present invention is referred to as "carbonate terminal", and the ratio of carbonate terminal to all terminals in the polycarbonate polyol is simply referred to as "carbonate terminal amount".

According to the method for producing a polycarbonate polyol of the present invention, the above polycarbonate polyol of the present invention can be produced. The method for producing the polycarbonate polyol of the present invention is not particularly limited, but it is preferably produced by the above method for producing the polycarbonate polyol of the present invention.
Hereinafter, the polycarbonate polyol produced by the method for producing the polycarbonate polyol of the present invention is also referred to as "the polycarbonate polyol of the present invention".

<1-1. Characteristics of Dioxane Generated Amount, Carbonate Terminal Amount, and APHA Value>
In the method for producing a polycarbonate polyol of the present invention, the amount of dioxane generated in the polycondensation step of a polyhydric alcohol and a carbonate compound is controlled to 1.0% by weight or less with respect to the amount of charged diethylene glycol used in the production of the polycarbonate polyol. One of its characteristics is to

If the amount of dioxane generated in the polycondensation step is more than the above upper limit, productivity will decrease due to by-production of dioxane, physical properties of the resulting polycarbonate polyol will decrease and coloring problems will occur, and further, this polycarbonate polyol will be used to produce polyurethane. This is not preferable because problems such as a decrease in reactivity during processing and a decrease in the quality of the produced polyurethane occur. The smaller the amount of dioxane generated, the more preferable from the viewpoint of the productivity of the polycarbonate polyol and the quality of the polycarbonate polyol and the polyurethane. , more preferably 0.3% by weight or less, and particularly preferably 0.1% by weight or less.
The amount of dioxane generated can be analyzed by the method described in the Examples section below. Equivalent to.

Further, one of the features of the polycarbonate polyol of the present invention is that the content of carbonate ends is 1.0 mol % or less and the APHA value is 50 or less.

If the amount of carbonate ends exceeds the above upper limit, the reactivity in the production of polyurethane using this polycarbonate polyol is poor, and it becomes difficult to produce a polyurethane having a high molecular weight and excellent mechanical strength, chemical resistance, and the like. Further, a high APHA value of the polycarbonate polyol means that the polycarbonate polyol is colored, which is not preferable as a quality of the polycarbonate polyol itself. Moreover, the polyurethane produced using this polycarbonate polyol is also colored, which is not preferable.

Therefore, the carbonate terminal content of the polycarbonate polyol of the present invention is preferably as small as possible, and is 1.0 mol % or less, preferably 0.5 mol % or less, more preferably 0.1 mol % or less.
The amount of carbonate ends can be analyzed by the method described in the Examples section below. Here, "0.1 mol% or less" is the detection limit of the amount of carbonate ends in the analysis of the polycarbonate polyol product. corresponds to

The APHA value of the polycarbonate polyol is also preferably low, and the APHA value of the polycarbonate polyol of the present invention is preferably 50 or less, more preferably 30 or less, still more preferably 20 or less. When the APHA value exceeds 50, the color tone of the polyurethane obtained using the polycarbonate diol-containing composition as a raw material deteriorates, the commercial value of the polyurethane deteriorates, and the thermal stability deteriorates. In particular, a polycarbonate diol-containing composition made from an aliphatic dihydroxy compound having an alcoholic hydroxyl group exhibits various excellent properties such as flexibility, water resistance, and light resistance when processed into polyurethane. It is not easy to make the APHA value 50 or less because the heat history and the coloring due to the catalyst tend to be more remarkable than when the compound is used as the raw material. The APHA value of the polycarbonate polyol is measured by the method described in the Examples section below.

<1-2. Means for achieving dioxane generation amount, carbonate terminal amount, and APHA value>
There are no particular restrictions on the means for achieving a dioxane generation amount of 1.0% by weight or less in the polycondensation step, but examples include the following methods (1) to (5). The following achievement means (1) to (5) may be adopted in combination, and from the viewpoint of certainty of achievement, the following achievement means (1) to (5) are adopted in combination. is preferred, and it is particularly preferred to employ all of them.
In addition, by adopting the following achievement means (1) to (5) to control the amount of dioxane generated to 1.0% by weight or less, the carbonate terminal amount is 1.0 mol% or less and the APHA value is 50 or less. It is also possible to produce a polycarbonate polyol of

(1) Diaryl carbonate, particularly preferably diphenyl carbonate, is used as a carbonate compound starting material. When a carbonate compound other than diaryl carbonate, such as diphenyl carbonate, is used, the unreacted diethylene glycol is heated for a long time due to its low reactivity with polyhydric alcohol, and the amount of dioxane generated tends to increase. That is, by using a highly reactive diaryl carbonate such as diphenyl carbonate as a starting material for the carbonate compound, the amount of dioxane generated can be reduced. Moreover, since the reactivity is high, the concentration of the catalyst shown in (2) below can be reduced, so that the amount of dioxane generated can be similarly reduced.

(2) In the polycondensation step, a metal salt of Group 2 of the long-period periodic table (simply referred to as the “periodic table” in the present invention) is used as a catalyst. When a catalyst other than a metal salt of Group 2 of the periodic table is used as the catalyst, the amount of dioxane generated tends to increase. For example, metal salts of Group 1 of the periodic table are too basic, and metal salts of Groups 3 and 4 are too acidic, which accelerates the dioxane generation reaction as a side reaction. be done. On the other hand, when a metal salt of Group 2 of the periodic table is used, only the desired esterification reaction can be accelerated as a moderately basic catalyst, so that the amount of dioxane generated can be reduced.
When using a metal salt of Group 2 of the periodic table, the concentration in terms of metal in the polycondensation reaction solution is preferably 50 ppm or less, more preferably 30 ppm or less, still more preferably 20 ppm or less, particularly preferably 15 ppm or less, and As the lower limit, 1 ppm or more is preferable for more reliably reducing the amount of dioxane generated. When the concentration of the group 2 metal salt of the periodic table exceeds the upper limit or is lower than the lower limit, the amount of dioxane generated tends to increase.

In addition, the metal salt of Group 2 of the periodic table usually does not volatilize and remains in the polycarbonate diol. , the residual amount thereof must be 50 ppm or less, preferably 30 ppm or less, as a weight ratio in terms of metal to the polycarbonate diol. , more preferably 20 ppm or less, particularly preferably 15 ppm or less. On the other hand, if the amount of the catalyst is small, the above problems may occur.

(3) The reaction temperature in the polycondensation step is 150° C. or higher and 180° C. or lower. If the reaction temperature is less than 150°C, the polycondensation reaction cannot proceed smoothly, and a polycarbonate polyol having a sufficient molecular weight cannot be produced, or the amount of residual carbonate ends increases. Decomposition of diethylene glycol tends to increase the amount of dioxane generated and cause coloration. The reaction temperature is preferably 160° C. or higher and 170° C. or lower.

(4) The reaction time in the polycondensation step is 3 hours or more and 20 hours or less. When the reaction time is less than 3 hours, the polycondensation reaction cannot proceed sufficiently, and a polycarbonate polyol having a sufficient molecular weight cannot be produced, or the residual amount of carbonate terminals increases. The decomposition of diethylene glycol and decarboxylation of terminal units of polycarbonate diol tend to increase the amount of dioxane generated and cause coloration. The reaction time is preferably 5 hours or more and 10 hours or less.

(5) Adjust the degree of decompression. Although the reaction can be carried out under normal pressure, the transesterification reaction is an equilibrium reaction, and the reaction can be biased toward the production system by distilling off the low-boiling components to be produced out of the system. Therefore, it is usually preferable to carry out the reaction while gradually lowering the pressure from the middle of the reaction and distilling off the low-boiling components produced.
In particular, it is preferable to carry out the reaction by increasing the degree of pressure reduction in the final stage of the reaction, since by-products such as monoalcohol, phenol and other low-boiling components can be distilled off. That is, the minimum pressure is preferably less than 1.5 kPa, particularly preferably 1.0 kPa or less, and most preferably 0.8 to 0.1 kPa. If the pressure exceeds the above upper limit, the reactivity may decrease, the reaction time may become longer, the amount of dioxane generated may increase, and the APHA of the resulting polycarbonate diol may increase. However, if the pressure is too low, the rate of distillation of the by-product phenol is high, so that the rate of polymerization is increased and the control of the molecular weight may become difficult.

<1-3. Structural features derived from raw material polyhydric alcohol>
<1-3-1. Oxyalkylene glycol (A1) and its content>
The polycarbonate polyol of the present invention contains 60% by weight or more of oxyalkylene glycol (A1) represented by the following formula (1) in raw material diol (A), and diethylene glycol as an essential component in oxyalkylene glycol (A1). By including the oxyalkylene glycol (A1) in such a ratio, flexibility and solvent resistance (hereinafter referred to as solvent resistance including chemical resistance) are excellent. From the viewpoint of flexibility and solvent resistance, the content of the oxyalkylene glycol (A1) in the diol (A) is preferably 70% by weight or more, particularly 80% by weight or more, and 90% by weight or more. is particularly preferred.

(In formula (1), m represents an integer of 2 to 4, and R ^A represents a carbon chain having 2 to 5 carbon atoms and may contain a branch. m R ^A contained in formula (1) may be the same or different).

In the polycarbonate polyol of the present invention obtained by using the oxyalkylene glycol (A1) in such a ratio, the ratio of the structural units derived from the oxyalkylene glycol (A1) to the total structural units derived from the diol (A) is Usually 60% by weight or more, preferably 70% by weight or more, more preferably 80% by weight or more, particularly preferably 90% by weight or more.

The oxyalkylene glycol (A1) is essentially diethylene glycol and is not particularly limited as long as it is represented by the above formula (1). ^RA preferably has 2 or 3 carbon atoms, more preferably 2 carbon atoms. The optionally branched carbon chain of 2 to 5 carbon atoms of R ^A specifically includes a linear or branched alkylene group of 2 to 5 carbon atoms.

Preferred examples of oxyalkylene glycol (A1) other than diethylene glycol include triethylene glycol, tetraethylene glycol, and dipropylene glycol. Only one of these oxyalkylene glycols (A1) may be used, or two or more thereof may be used.

As the oxyalkylene glycol (A1), it is particularly preferable to use diethylene glycol, or diethylene glycol and triethylene glycol. % by weight or more, particularly 80% by weight or more, particularly preferably 90% by weight or more, from the viewpoint of flexibility and chemical resistance. Moreover, the upper limit of this content ratio is usually preferably 99.5% by weight or less, more preferably 99% by weight or less, and even more preferably 98% by weight or less.
The oxyalkylene glycol (A1) used in the present invention contains diethylene glycol, and the content of diethylene glycol in the raw material diol (A) is 50% by weight or more, preferably 60% by weight or more, particularly 70% by weight or more. is preferred from the viewpoint of flexibility and chemical resistance.

In particular, the combined use of diethylene glycol and triethylene glycol as the oxyalkylene glycol (A1) disturbs the regularity of the structural units in the polycarbonate polyol chain, thereby preventing aggregation due to hydrogen bonding and increasing flexibility. This is a preferred embodiment of the present invention, in which case the ratio of diethylene glycol and triethylene glycol used is diethylene glycol: triethylene glycol = 10:90 to 90:10, especially 20:80 to 80:20 by weight. is preferred, 30:70 to 70:30 is more preferred, and 40:60 to 60:40 is particularly preferred.

When the raw material diol (A) of the polycarbonate polyol of the present invention contains a diol other than the oxyalkylene glycol (A1) represented by the formula (A1), the other diols include ethylene glycol, 1,3- Propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decane diols, linear diols having 2 to 20 carbon atoms such as 1,11-undecanediol and 1,12-dodecanediol, 2-methyl-1,3-propanediol, 2-ethyl-1,3-propanediol, 2 ,2-dimethyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 3-methyl-1,5-pentanediol , 3,3-dimethyl-1,5-pentanediol, 2,2,4,4-tetramethyl-1,5-pentanediol, 2-ethyl-1,6-hexanediol, etc. branched diols, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 4,4-dicyclohexyldimethylmethanediol, 2,2′-bis(4-hydroxycyclohexyl)propane, 4, Cyclic diols having 6 to 20 carbon atoms such as 4′-isopropylidenedicyclohexanol, norbornane-2,3-dimethanol, etc., isosorbide, 3,4-dihydroxytetrahydrofuran, 3,9-bis(1,1-dimethyl -2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane (cas number: 1455-42-1), 2-(5-ethyl-5-hydroxymethyl-1,3 -Dioxan-2-yl)-2-methylpropan-1-ol (cas number: 59802-10-7) and other cyclic diols having a heteroatom in the ring.

These other diols may be used alone or in combination of two or more. In order to obtain this, the content in the diol (A) is 40% by weight or less, preferably 30% by weight or less, more preferably 20% by weight or less, and particularly preferably 10% by weight or less.

<1-3-2. Branched alcohol (B) and its content>
For the polycarbonate polyol of the present invention, the diol (A) containing the oxyalkylene glycol (A1) in the above ratio and the branched alcohol (B) may be used as raw material polyhydric alcohols. In this case, the structural unit derived from the branched alcohol (B) in the polycarbonate polyol is 0.005 mol% or more and 5.0 mol% or less with respect to the total structural units derived from the polyhydric alcohol in the polycarbonate polyol. Thus, the crosslinked structure introduced by the branched alcohol (B) can be excellent in mechanical strength without impairing the flexibility and solvent resistance of the oxyalkylene glycol (A1), which is preferable.

From the viewpoint of compatibility between flexibility and solvent resistance and mechanical strength, the ratio of the structural units derived from the branched alcohol (B) to the structural units derived from the polyhydric alcohol in the polycarbonate polyol of the present invention is 0.005. It is preferably up to 5.0 mol %, more preferably 0.05 to 3.0 mol %, even more preferably 0.5 to 2.0 mol %.

In order to make the structural units derived from the branched alcohol (B) occupying the structural units derived from the polyhydric alcohol in the polycarbonate polyol within the above range, the moles of the branched alcohol (B) occupying the polyhydric alcohol used as the starting material for the polycarbonate polyol What is necessary is just to make a content rate into the said range.
That is, in general, the ratio of each polyhydric alcohol in the raw material polyhydric alcohol is the ratio of the structural units derived from each polyhydric alcohol to the total number of structural units derived from the polyhydric alcohol in the resulting polycarbonate polyol. will be approximately equal.

Examples of trivalent to hexavalent branched alcohols (B) having 3 to 12 carbon atoms contained in the raw material polyhydric alcohol of the polycarbonate polyol of the present invention include glycerol, trimethylolmethane, trimethylolethane, trimethylolpropane, and trimethylolbutane. , 1,2,4-butanetriol, 1,2,3-hexanetriol, 1,2,4-hexanetriol, tris(hydroxymethyl)amine, tris(hydroxyethyl)amine, tris(hydroxypropyl)amine, penta Examples include erythritol, diglycerol, triglycerol, polyglycerol, bis(trimethylolpropane), tris(hydroxymethyl)isocyanurate, tris(hydroxyethyl)isocyanurate, sugars such as glucose, and sugar derivatives such as sorbitol. The polycarbonate polyol of the present invention may contain only one type of structural units derived from these branched alcohols (B), or may contain two or more types. That is, the number of branched alcohols (B) used as raw material polyhydric alcohols for the polycarbonate polyol of the present invention may be one, or two or more.

Of these, branched alcohols containing at least a portion, preferably all, of hydroxyl groups as methylol groups are particularly preferred from the viewpoint of the efficiency of introduction of a crosslinked structure, and the number of carbon atoms is preferably as small as possible. That is, a methylol group has a structure having a hydroxyl group via a methylene group, and thus has high reactivity. Moreover, when branched alcohols with the same number of moles are added, the one with a smaller number of carbon atoms can increase the crosslink density. However, if the number of carbon atoms in the branched alcohol (B) is too small, the reactivity of each hydroxyl group will deteriorate due to steric hindrance, and the cross-linking will be difficult to proceed. In addition, the cross-linking points are too dense, which may promote gelation. Accordingly, the branched alcohol (B) is preferably a branched alcohol having 3 to 12 carbon atoms and having a trivalent to hexavalent methylol group, more preferably 4 to 10 carbon atoms. Specifically, trihydric alcohols such as glycerol, trimethylolpropane, trimethylolethane, and trimethylolmethane, tetrahydric alcohols such as pentaerythritol and ditrimethylolpropane, and hexahydric alcohols such as dipentaerythritol are preferred, and particularly moderate A trihydric alcohol capable of forming a structural unit with a crosslink density and preventing gelation is preferred, and trimethylolpropane, which contains three highly reactive methylol groups, is easily available industrially and is inexpensive, is most preferred.

<1-3-3. Preferred raw material polyhydric alcohol>
The polycarbonate polyol of the present invention preferably uses, as raw material polyhydric alcohols, a diol (A) containing diethylene glycol or diethylene glycol and triethylene glycol, and a branched alcohol (B) containing trimethylolpropane, particularly diethylene glycol. , Using triethylene glycol and trimethylolpropane, 30 to 70 mol% of diethylene glycol, 30 to 70 mol% of triethylene glycol, and 0.005 to 5 mol% of trimethylolpropane with respect to the total 100 mol% of these, It is preferable from the viewpoint of flexibility, solvent resistance and mechanical strength.

The raw material polyhydric alcohol for the polycarbonate polyol of the present invention includes polyhydric alcohols other than the diol (A) and the branched alcohol (B) described above, such as trivalent or higher linear alcohols and trivalent or higher cyclic alcohols. However, in order to effectively obtain the above effects by using the diol (A) and the branched alcohol (B), the polyhydric alcohol other than the diol (A) and the branched alcohol (B) in the raw material polyhydric alcohol The alcohol content is 30% by weight or less, particularly 20% by weight or less, further 10% by weight or less, and it is most preferred that these alcohols are not contained in the starting polyhydric alcohol.

<1-4. Carbonate compound>
The carbonate compound used for producing the polycarbonate polyol of the present invention is not limited as long as it does not impair the effects of the present invention, and includes dialkyl carbonate, diaryl carbonate and alkylene carbonate.
Of these, the use of diaryl carbonate has the advantage of allowing the reaction to proceed rapidly and reacting with structural units in polyhydric alcohols and polycarbonate polyols with low reactivity, which in turn reduces the ratio of carbonate terminal structures. .
Moreover, as described above, from the viewpoint of reducing the amount of dioxane generated, it is preferable to use a diaryl carbonate such as diphenyl carbonate as the carbonate compound.

Specific examples of dialkyl carbonates, diaryl carbonates, and alkylene carbonates that can be used for producing the polycarbonate polyol according to the present invention are as follows.

Examples of dialkyl carbonate include dimethyl carbonate, diethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate, diisobutyl carbonate, ethyl-n-butyl carbonate, ethyl isobutyl carbonate and the like, preferably dimethyl carbonate and diethyl carbonate.

Examples of diaryl carbonate include diphenyl carbonate, ditolyl carbonate, bis(chlorophenyl) carbonate, di-m-cresyl carbonate and the like, preferably diphenyl carbonate.

Examples of alkylene carbonates include ethylene carbonate, trimethylene carbonate, tetramethylene carbonate, 1,2-propylene carbonate, 1,2-butylene carbonate, 1,3-butylene carbonate, 2,3-butylene carbonate, 1,2- pentylene carbonate, 1,3-pentylene carbonate, 1,4-pentylene carbonate, 1,5-pentylene carbonate, 2,3-pentylene carbonate, 2,4-pentylene carbonate, neopentyl carbonate, etc. ethylene carbonate, preferably ethylene carbonate.

These may be used individually by 1 type, and may use 2 or more types together.

Among these, diaryl carbonate is preferred because it is highly reactive and efficient in terms of industrial production, and diphenyl carbonate, which is readily available as an industrial raw material at low cost, is more preferred. As described above, diphenyl carbonate is also preferable from the viewpoint of reducing the amount of dioxane generated, the amount of carbonate ends, and the APHA value.

In the production of the polycarbonate polyol of the present invention, the amount of the carbonate compound used is not particularly limited. It is more preferably 0.60, and the upper limit is preferably 1.00, more preferably 0.98, still more preferably 0.97. If the amount of the carbonate compound used exceeds the above upper limit, the proportion of non-hydroxy terminal groups in the resulting polycarbonate polyol may increase, or the molecular weight may not fall within the predetermined range. or the raw material polyhydric alcohol may remain.

<1-5. transesterification catalyst>
The polycarbonate polyol of the present invention can be produced by subjecting the aforementioned polyhydric alcohol and carbonate compound to polycondensation through a transesterification reaction.

In the production of the polycarbonate polyol of the present invention, a transesterification catalyst (hereinafter sometimes referred to as a catalyst) is usually used to promote polycondensation. As the transesterification catalyst, any compound generally considered to have transesterification ability can be used without limitation.

Examples of transesterification catalysts include compounds of Group 1 metals of the periodic table such as lithium, sodium, potassium, rubidium and cesium; compounds of Group 2 metals of the periodic table such as magnesium, calcium, strontium and barium; titanium and zirconium. Compounds of Group 4 metals of the periodic table such as hafnium; compounds of Group 5 metals of the periodic table such as hafnium; compounds of Group 9 metals of the periodic table such as cobalt; compounds of Group 12 metals of the periodic table such as zinc; Group 13 metal compounds of the periodic table; compounds of group 14 metals of the periodic table such as germanium, tin and lead; compounds of group 15 metals of the periodic table such as antimony and bismuth; lanthanides such as lanthanum, cerium, europium and ytterbium metal compounds and the like. Among these, from the viewpoint of increasing the transesterification reaction rate, periodic table group 1 metal compounds, periodic table group 2 metal compounds, periodic table group 4 metal compounds, periodic table group 5 metal compounds, A compound of a metal of Group 9 of the periodic table, a compound of a metal of Group 12 of the periodic table, a compound of a metal of Group 13 of the periodic table, a compound of a metal of Group 14 of the periodic table, a compound of a metal of Group 1 of the periodic table, a compound of a metal of Group 1 of the periodic table, Compounds of Group 2 metals are more preferred, and compounds of Group 2 metals of the periodic table are even more preferred. Among the compounds of Group 1 metals of the periodic table, lithium, potassium and sodium compounds are preferred, lithium and sodium compounds are more preferred, and sodium compounds are even more preferred. Among the compounds of Group 2 metals of the periodic table, compounds of magnesium, calcium and barium are preferred, compounds of calcium and magnesium are more preferred, and compounds of magnesium are even more preferred. These metal compounds are mainly used as hydroxides, salts and the like. Examples of salts when used as salts include halide salts such as chlorides, bromides and iodides; carboxylates such as acetates, formates and benzoates; methanesulfonates and toluenesulfonates; , sulfonates such as trifluoromethanesulfonate; phosphorus-containing salts such as phosphates, hydrogen phosphates and dihydrogen phosphates; acetylacetonate salts; Catalyst metals can also be used as alkoxides such as methoxides and ethoxides.

Among these, the acetates, nitrates, sulfates, carbonates, phosphates, hydroxides, halides, and alkoxides of at least one metal selected from Group 2 metals of the periodic table are preferred, and more Preferred are group 2 metal acetates, carbonates, and hydroxides of the periodic table, more preferred are magnesium and calcium acetates, carbonates, and hydroxides, and particularly preferred are magnesium and calcium acetates. , most preferably magnesium acetate.
In addition, from the viewpoint of reacting the less reactive oxyalkylene glycol (A1), the branched alcohol (B), the end group of the oxyaryl structure derived from the carbonate compound, etc. that may be contained in the polycarbonate polyol of the present invention, a low-period metal compounds of Group 1 metals of the periodic table, compounds of group 2 metals of the periodic table, and compounds of group 4 of the periodic table that exhibit high transesterification catalysis due to their low electronegativity and strong coordination with carbonate compounds. Metal acetates, nitrates, sulfates, carbonates, phosphates, hydroxides, halides and alkoxides are preferred. On the other hand, strong acidity and strong bases cause decomposition of the oxyalkylene glycol (A1) contained in the raw material and the polycarbonate polyol structural unit, and harmful low-molecular-weight compounds (1,4-dioxane) that do not increase the molecular weight are produced as secondary substances. Compounds of Group 2 metals of the periodic table with moderate basicity are preferred, due to the problem of generation. In order to reduce the branched alcohol (B), which has particularly low reactivity, and the end groups of the oxyaryl structure derived from carbonate compounds, magnesium and calcium acetates, carbonates, and hydroxides that are highly stable even after long-term reactions are used. is preferred, most preferred is magnesium acetate.
Furthermore, as described above, from the viewpoint of reducing the amount of dioxane generated in the polycondensation step, the amount of carbonate ends in the polycarbonate polyol obtained, and the APHA value, metal salts of Group 2 of the periodic table are preferable, and magnesium, calcium acetate, and Carbonates are preferred, most preferably magnesium acetate.

When the above catalyst is used, if too much catalyst remains in the resulting polycarbonate polyol, the reaction may be inhibited or accelerated excessively during the production of polyurethane using the polycarbonate polyol. Sometimes.

Therefore, when using a transesterification catalyst, the amount used is preferably an amount that does not affect the performance even if it remains in the resulting polycarbonate polyol. , the upper limit is preferably 500 ppm, more preferably 100 ppm, even more preferably 50 ppm, particularly preferably 10 ppm. On the other hand, the lower limit is the amount at which sufficient polymerization activity can be obtained, preferably 0.01 ppm, more preferably 0.1 ppm, and even more preferably 1 ppm.
Further, when a compound of a Group 2 metal of the periodic table is used as a catalyst, the total amount of all metal atoms thereof is preferably 5 μmol or more, more preferably 7 μmol or more, and still more preferably 10 μmol per 1 mol of the total polyhydric alcohol used as a raw material. Above, it is preferably 500 μmol or less, more preferably 300 μmol or less, still more preferably 100 μmol or less, and particularly preferably 50 μmol or less.

Further, as described above, from the viewpoint of reducing the amount of dioxane generated in the polycondensation step and reducing the amount of carbonate ends and the APHA value of the resulting polycarbonate polyol, when a metal salt of Group 2 of the periodic table is used as a catalyst, The concentration in terms of metal in the polycondensation reaction solution is preferably 50 ppm or less, more preferably 30 ppm or less, still more preferably 20 ppm or less, particularly preferably 15 ppm or less, and the lower limit is preferably 1 ppm or more.

<1-6. Method for producing polycarbonate polyol>
The polycarbonate polyol of the present invention uses the above-mentioned polyhydric alcohol and the above-mentioned carbonate compound in the above-mentioned ratio, and in the presence of an optionally used transesterification catalyst, the above-mentioned (1) to (5). It can be produced by transesterification and polycondensation by adopting the achievement means. The manufacturing method thereof will be described below.

The method of charging the reaction raw materials is not particularly limited. A method of simultaneously charging the entire amount of the polyhydric alcohol, the carbonate compound and the transesterification catalyst and subjecting them to the reaction, or when the carbonate compound is solid, the carbonate compound is first charged and then heated and melted. A method in which the polyhydric alcohol and the transesterification catalyst are added later, a method in which the polyhydric alcohol is charged first and then melted, and a carbonate compound and the transesterification catalyst are added thereto. A method can be freely selected, such as a method of reacting a part with carbonate compounds or chlorocarbonates to synthesize a diester carbonate derivative of a polyhydric alcohol and then reacting it with the remaining polyhydric alcohol.
In the method for producing the polycarbonate polyol of the present invention, it is also possible to adopt a method of adding part of the polyhydric alcohol used at the end of the reaction in order to reduce the amount of carbonate ends. At that time, the upper limit of the amount of polyhydric alcohol to be added last is usually 20%, preferably 15%, more preferably 10% of the amount of polyhydric alcohol to be charged, and the lower limit is usually It is 0.1%, preferably 0.5%, more preferably 1.0%.

The suitable reaction temperature for the polycondensation reaction is as described above. If the reaction temperature is too high, the resulting polycarbonate polyol may be colored, or the ether structure may be degraded due to decarboxylation of carbonate groups or dehydration condensation between polyhydric alcohols. quality problems may occur. In addition, since the polycarbonate polyol of the present invention contains a structural unit derived from odiethylene glycol, if the above upper limit is exceeded, there are problems such as the oxyalkylene chain being cleaved and harmful dioxane being generated due to dehydration condensation.

Although the reaction can be carried out under normal pressure, the transesterification reaction is an equilibrium reaction, and the reaction can be biased towards the production system by distilling off the low-boiling components to be produced out of the system. Therefore, in the latter half of the reaction, it is usually preferable to adopt reduced pressure conditions and carry out the reaction while distilling off the low-boiling components. Alternatively, it is also possible to carry out the reaction while gradually lowering the pressure in the middle of the reaction and distilling off the low-boiling components produced.
In particular, it is preferable to carry out the reaction by increasing the degree of pressure reduction in the final stage of the reaction, since by-products such as alcohols and phenols can be distilled off.
In this case, the reaction pressure at the end of the polycondensation reaction is preferably set to the degree of pressure reduction described above.
At this time, in order to effectively distill off the low-boiling components, the reaction may be carried out while passing a small amount of an inert gas such as nitrogen, argon or helium into the reaction system.

In order to prevent the raw material from being distilled off in the initial stage of the reaction, a reflux pipe may be attached to the reactor to carry out the reaction while refluxing the carbonate compound and the polyhydric alcohol. In this case, it is possible to accurately adjust the ratio of the reagents without losing the charged raw materials, which is preferable.

The reaction time is also as described above, preferably 3 hours or more and 20 hours or less, particularly 5 hours or more and 10 hours or less.

As described above, when an ester exchange catalyst is used in the polycondensation reaction, the ester exchange catalyst usually remains in the polycarbonate polyol obtained. may not be possible. In order to suppress the effect of this residual catalyst, a phosphoric acid-based deactivator may be added after the polycondensation step and before the step of removing unreacted monomers. Furthermore, after adding the phosphoric acid-based deactivator, heat treatment as described later can efficiently deactivate the transesterification catalyst.

Examples of the phosphoric acid-based deactivator used for deactivating the transesterification catalyst include inorganic phosphoric acid such as phosphoric acid and phosphorous acid, dibutyl phosphate, tributyl phosphate, trioctyl phosphate, and triphosphate. organic phosphates such as phenyl and triphenyl phosphite;
These may be used individually by 1 type, and may use 2 or more types together.

The amount of the phosphoric acid-based deactivator used is not particularly limited, but it is preferably approximately equimolar to the used ester exchange catalyst, specifically, per 1 mol of the used ester exchange catalyst The upper limit is preferably 5 mol, more preferably 2 mol, and the lower limit is preferably 0.6 mol, more preferably 0.8 mol, still more preferably 1.0 mol. When the phosphoric acid-based deactivator is used in an amount less than this, the deactivation of the transesterification catalyst is insufficient, and when the obtained polycarbonate polyol is used as a raw material for polyurethane production, for example, the isocyanate group of the polycarbonate polyol It may not be possible to sufficiently reduce the reactivity to Also, if a phosphoric acid-based deactivator exceeding this range is used, the obtained polycarbonate polyol may be colored.

Deactivation of the transesterification catalyst by adding a phosphoric acid-based deactivator can be carried out at room temperature, but is more efficient when heated. The temperature of this heat treatment is not particularly limited, but the upper limit is preferably 180° C., more preferably 150° C., still more preferably 120° C., particularly preferably 100° C., and the lower limit is preferably 50° C., more preferably 50° C. is 60°C, more preferably 70°C. If the temperature is lower than this, deactivation of the transesterification catalyst takes a long time and is not efficient, and the degree of deactivation may be insufficient. On the other hand, if the temperature exceeds the upper limit, the resulting polycarbonate polyol may be colored.
Although the reaction time with the phosphoric acid deactivator is not particularly limited, it is usually 0.1 to 5 hours.

After the polycondensation reaction, impurities with an alkyloxy terminal structure in the polycarbonate polyol, impurities with an aryloxy group, phenols, unreacted monomers such as raw polyhydric alcohols and carbonate compounds, and added catalysts, etc. It is preferable to purify for the purpose of removing For purification at that time, a method of distilling off light boiling compounds by distillation can be adopted. Specific methods of distillation include reduced-pressure distillation, steam distillation, thin-film distillation, and the like, but the thin-film distillation is particularly effective. In addition, in order to remove water-soluble impurities, washing may be performed with water, alkaline water, acidic water, a chelating agent-dissolved solution, or the like. In that case, the compound to be dissolved in water can be arbitrarily selected.

The conditions for thin film distillation are not particularly limited, but the upper limit of the temperature during thin film distillation is preferably 250°C, more preferably 200°C. Also, the lower limit is preferably 120°C, more preferably 150°C.
By setting the lower limit of the temperature during thin-film distillation to the above value, the effect of removing light-boiling components becomes sufficient. Further, by setting the upper limit to 250° C., there is a tendency to prevent the polycarbonate polyol obtained after thin-film distillation from being colored.

The upper limit of the pressure during thin film distillation is preferably 500 Pa, more preferably 150 Pa, and even more preferably 50 Pa. By setting the pressure during thin-film distillation to the above upper limit or less, there is a tendency that a sufficient effect of removing low-boiling components can be obtained.
The upper limit of the temperature for keeping the polycarbonate polyol immediately before the thin film distillation is preferably 250°C, more preferably 150°C. Also, the lower limit is preferably 80°C, more preferably 120°C.

By setting the temperature at which the polycarbonate polyol is kept warm immediately before the thin film distillation to be equal to or higher than the lower limit, there is a tendency to prevent the decrease in fluidity of the polycarbonate polyol immediately before the thin film distillation. On the other hand, when the amount is not more than the upper limit, there is a tendency to prevent the polycarbonate polyol obtained after thin-film distillation from being colored.

<1-7. Physical Properties of Polycarbonate Polyol>
<1-7-1. Hydroxyl value>
The lower limit of the hydroxyl value of the polycarbonate polyol of the present invention is 20 mgKOH/g, preferably 25 mgKOH/g, more preferably 30 mgKOH/g, still more preferably 35 mgKOH/g. In addition, the upper limit of the hydroxyl value of the polycarbonate polyol is 450 mgKOH/g, preferably 230 mgKOH/g, more preferably 150 mgKOH/g, still more preferably 120 mgKOH/g, still more preferably 75 mgKOH/g, particularly preferably 60 mgKOH/g, most preferably 60 mgKOH/g. Preferably it is 45 mgKOH/g. If the hydroxyl value is less than the above lower limit, the viscosity may become too high and handling may become difficult during polyurethane formation.

<1-7-2. Molecular Weight Distribution>
The weight average molecular weight/number average molecular weight (Mw/Mn), which is the molecular weight distribution of the polycarbonate polyol of the present invention, is not particularly limited, but the lower limit is preferably 1.5, more preferably 1.8. The upper limit of weight average molecular weight/number average molecular weight (Mw/Mn) is preferably 3.5, more preferably 3.0. When the molecular weight distribution exceeds the above range, the physical properties of the polyurethane produced using this polycarbonate polyol tend to become hard at low temperatures and the elongation tends to decrease. Then, a sophisticated purification operation such as removal of oligomers may be required.
The weight average molecular weight of the polycarbonate polyol of the present invention is the polystyrene equivalent weight average molecular weight, and the number average molecular weight of the polycarbonate polyol of the present invention is the polystyrene equivalent number average molecular weight. may be abbreviated).

<1-7-3. Molecular chain end>
The molecular chain ends of the polycarbonate polyol of the present invention are mainly hydroxyl groups. However, in the case of a polycarbonate polyol obtained by the reaction of a polyhydric alcohol and a carbonate compound, there is a possibility that a portion of the molecular chain ends that are not hydroxyl groups may be present as impurities. A specific example thereof is one having an alkyloxy group or an aryloxy group at the molecular chain terminal, and most of them have a carbonate terminal structure.

For example, when diphenyl carbonate is used as the carbonate compound, the phenoxy group (PhO-) is used as the aryloxy group at the end of the carbonate, and when dimethyl carbonate is used, the methoxy group (MeO-) is used as the alkyloxy group, and diethyl carbonate is used. is an ethoxy group (EtO-), and when ethylene carbonate is used, a hydroxyethoxy group (HOCH ₂ CH ₂ O-) may remain as a molecular chain terminal (where Ph represents a phenyl group, Me represents a methyl group and Et represents an ethyl group).
As described above, the carbonate terminal content of the polycarbonate polyol of the present invention is preferably 1.0 mol% or less, more preferably 0.8 mol% or less, still more preferably 0.5 mol% or less, and particularly preferably 0.1 mol% or less. be. The terminal structure and terminal amount can usually be determined by ¹ H-NMR measurement.

<1-7-4. Residual Monomers, etc.>
When a diaryl carbonate such as diphenyl carbonate is used as a raw material, phenols are produced as a by-product during the production of polycarbonate polyol. Since phenols are monofunctional compounds, they may become a hindrance factor in the production of polyurethane, and the urethane bonds formed by phenols have weak bonding strength, so they can be damaged by heat in subsequent processes. It may dissociate, regenerate isocyanate and phenols, and cause problems. Moreover, since phenols are also stimulating substances, it is preferable that the residual amount of phenols in the polycarbonate polyol is as small as possible. Specifically, the weight ratio to the polycarbonate polyol is preferably 1000 weight ppm or less, more preferably 500 weight ppm or less, still more preferably 300 weight ppm or less, and particularly preferably 100 weight ppm or less. In order to reduce the amount of phenols in the polycarbonate polyol, it is effective to set the pressure of the polymerization reaction of the polycarbonate polyol to a high vacuum of 1 kPa or less as absolute pressure, or to perform thin film distillation or the like after the polymerization of the polycarbonate polyol.

In addition, the carbonate compound used as a raw material in manufacturing may remain in the polycarbonate polyol. The amount of the carbonate compound remaining in the polycarbonate polyol is not limited, but is preferably as small as possible. be. If the content of the carbonate compound in the polycarbonate polyol is too high, the reaction during polyurethane formation may be inhibited. On the other hand, the lower limit is not particularly limited, but is preferably 0.1% by weight, more preferably 0.01% by weight, and still more preferably 0% by weight.

Moreover, the polyhydric alcohol used at the time of production may remain in the polycarbonate polyol. The residual amount of the polyhydric alcohol in the polycarbonate polyol is not limited, but is preferably as small as possible. Preferably, it is 0.05% by weight or less. If the amount of residual polyhydric alcohol in the polycarbonate polyol is large, the molecular length of the soft segment portion of the polyurethane becomes insufficient, and desired physical properties may not be obtained.

Moreover, polycarbonate polyols may contain cyclic carbonates (cyclic oligomers) that are by-produced during production. For example, when 1,3-propanediol is used, 1,3-dioxan-2-one or a cyclic carbonate formed from two or more molecules of 1,3-dioxan-2-one may be formed and contained in the polycarbonate polyol. be. These compounds may cause side reactions in the polyurethane formation reaction and cause turbidity. It is preferable to remove as much as possible by performing thin film distillation or the like later. The content of these cyclic carbonates contained in the polycarbonate polyol is not limited, but is preferably 3% by weight or less, more preferably 1% by weight or less, and still more preferably 0.5% by weight or less as a weight ratio to the polycarbonate polyol. .

[2. Polyurethane manufacturing method]
Polyurethanes can be made using the polycarbonate polyols of the present invention.
The polyurethane produced using the polycarbonate polyol of the present invention is hereinafter referred to as "the polyurethane of the present invention".
The method for producing the polyurethane of the present invention using the polycarbonate polyol of the present invention employs known polyurethane-forming reaction conditions for producing ordinary polyurethanes.

For example, the polyurethane of the present invention can be produced by reacting the polycarbonate polyol of the present invention with a polyisocyanate and a chain extender at a temperature ranging from room temperature to 200°C.
Alternatively, the polycarbonate polyol of the present invention may be first reacted with an excess amount of polyisocyanate to produce a prepolymer having terminal isocyanate groups, and then a chain extender may be used to increase the degree of polymerization to produce the polyurethane of the present invention. can be done.

<2-1. Polyisocyanate>
Polyisocyanates used to produce polyurethanes using the polycarbonate polyols of the present invention include various known aliphatic, alicyclic or aromatic polyisocyanate compounds.

For example, the carboxyl groups of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate and dimer acid were converted to isocyanate groups. Aliphatic diisocyanates such as dimer diisocyanate; 1,4-cyclohexane diisocyanate, isophorone diisocyanate, 1-methyl-2,4-cyclohexane diisocyanate, 1-methyl-2,6-cyclohexane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate ,4-bis(isocyanatomethyl)cyclohexane and 1,3-bis(isocyanatomethyl)cyclohexane; xylylene diisocyanate, 4,4′-diphenyl diisocyanate, 2,4-tolylene diisocyanate, 2,6 -tolylene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate , 1,5-naphthylene diisocyanate, 3,3′-dimethyl-4,4′-biphenylene diisocyanate, polymethylene polyphenyl isocyanate, phenylene diisocyanate and m-tetramethylxylylene diisocyanate. These may be used individually by 1 type, and may use 2 or more types together.

Among these, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and isophorone are preferable in terms of the balance of physical properties of the resulting polyurethane and in terms of industrial availability in large quantities at low cost. Diisocyanates are preferred.

<2-2. Chain extender>
The chain extender used in producing the polyurethane of the present invention is a low-molecular-weight compound having at least two active hydrogens that react with isocyanate groups when producing a prepolymer having an isocyanate group, which will be described later, and is usually a polyol. and polyamines.

Specific examples include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol and 1,9-nonanediol. , 1,10-decanediol, 1,12-dodecanediol, and other linear diols; 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 2,2-diethyl -1,3-propanediol, 2-methyl-2-propyl-1,3-propanediol, 2-methyl-1,4-butanediol, 2,4-heptanediol, 1,4-dimethylolhexane, 2 -ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol , diols having a branched chain such as dimer diol; diols having an ether group such as diethylene glycol and propylene glycol; Diols having a ring structure, diols having an aromatic group such as xylylene glycol, 1,4-dihydroxyethylbenzene, 4,4′-methylenebis(hydroxyethylbenzene); polyols such as glycerin, trimethylolpropane, pentaerythritol hydroxyamines such as N-methylethanolamine and N-ethylethanolamine; ethylenediamine, 1,3-diaminopropane, hexamethylenediamine, triethylenetetramine, diethylenetriamine, isophoronediamine, 4,4′-diaminodicyclohexylmethane, 2 -hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine, 4,4'-diphenylmethanediamine, methylenebis(o-chloro aniline), polyamines such as xylylenediamine, diphenyldiamine, tolylenediamine, hydrazine, piperazine, N,N'-diaminopiperazine; and water.

These chain extenders may be used alone or in combination of two or more. Among these, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1 ,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,4-cyclohexanedimethanol, 1,4-dihydroxyethylcyclohexane, ethylenediamine, 1,3-diaminopropane, isophoronediamine, 4, 4'-Diaminodicyclohexylmethane is preferred.

In addition, the chain extender in the case of producing a prepolymer having a hydroxyl group, which will be described later, is a low molecular weight compound having at least two isocyanate groups, specifically <2-1. polyisocyanate>.

<2-3. Chain terminator>
When producing the polyurethane of the present invention, a chain terminating agent having one active hydrogen group can be used as necessary for the purpose of controlling the molecular weight of the resulting polyurethane.

These chain terminators include aliphatic monools having one hydroxyl group such as methanol, ethanol, propanol, butanol and hexanol, diethylamine, dibutylamine, n-butylamine, monoethanolamine and diethanolamine having one amino group. , morpholine, and other aliphatic monoamines.
These may be used individually by 1 type, and may use 2 or more types together.

<2-4. Catalyst>
In the polyurethane-forming reaction for producing the polyurethane of the present invention, an amine-based catalyst such as triethylamine, N-ethylmorpholine and triethylenediamine, or an acid-based catalyst such as acetic acid, phosphoric acid, sulfuric acid, hydrochloric acid and sulfonic acid, and trimethyltin laurate. , dibutyltin dilaurate, dioctyltin dilaurate, dioctyltin dineodecanate, and other tin-based compounds, and furthermore, known urethane polymerization catalysts typified by organic metal salts such as titanium-based compounds can also be used. A urethane polymerization catalyst may be used individually by 1 type, and may use 2 or more types together.

<2-5. Polyol other than the polycarbonate polyol of the present invention>
In the polyurethane-forming reaction when producing the polyurethane of the present invention, the polycarbonate polyol of the present invention may be used in combination with other polyols, if desired. Here, the polyol other than the polycarbonate polyol of the present invention is not particularly limited as long as it is used in ordinary polyurethane production. mentioned. For example, when used in combination with polyether polyol, it is possible to obtain a polyurethane with further improved flexibility, which is a feature of the polycarbonate polyol of the present invention. Here, the weight ratio of the polycarbonate polyol of the present invention to the combined weight of the polycarbonate polyol of the present invention and other polyols is preferably 70% or more, more preferably 90% or more. If the weight ratio of the polycarbonate polyol of the present invention is small, the balance between flexibility and solvent resistance, which are characteristics of the polycarbonate polyol of the present invention, may be lost.

In the present invention, the polycarbonate polyol of the present invention described above can be modified and used for the production of polyurethane. As a method for modifying polycarbonate polyol, an epoxy compound such as ethylene oxide, propylene oxide, butylene oxide is added to polycarbonate polyol to introduce an ether group. , sebacic acid, terephthalic acid, etc. and their ester compounds to introduce an ester group. Ether modification is preferable because modification with ethylene oxide, propylene oxide, or the like reduces the viscosity of the polycarbonate polyol, and is therefore easy to handle. In particular, by modifying the polycarbonate polyol of the present invention with ethylene oxide or propylene oxide, the crystallinity of the polycarbonate polyol is reduced and the flexibility at low temperatures is improved. Since the water absorption and moisture permeability of the polyurethane that has been treated with the material increases, the performance of the artificial leather/synthetic leather may be improved. However, when the addition amount of ethylene oxide or propylene oxide is increased, various physical properties such as mechanical strength, heat resistance, and solvent resistance of the polyurethane produced using the modified polycarbonate polyol are lowered. ~50% by weight is suitable, preferably 5-40% by weight, more preferably 5-30% by weight. In addition, the method of introducing an ester group is preferable because modification with ε-caprolactone lowers the viscosity of the polycarbonate polyol and ease of handling. The amount of ε-caprolactone added to the polycarbonate polyol is preferably 5 to 50% by weight, preferably 5 to 40% by weight, more preferably 5 to 30% by weight. If the amount of ε-caprolactone added exceeds 50% by weight, the hydrolysis resistance, chemical resistance, etc. of the polyurethane produced using the modified polycarbonate polyol are lowered.

<2-6. Solvent>
The polyurethane-forming reaction in producing the polyurethane of the present invention may employ a solvent.
Preferred solvents include amide solvents such as dimethylformamide, diethylformamide, dimethylacetamide and N-methylpyrrolidone; sulfoxide solvents such as dimethylsulfoxide; ketone solvents such as methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; ether-based solvents; ester-based solvents such as methyl acetate, ethyl acetate and butyl acetate; and aromatic hydrocarbon-based solvents such as toluene and xylene. These solvents may be used alone or as a mixed solvent of two or more.

Preferred organic solvents among these are methyl ethyl ketone, ethyl acetate, toluene, dimethylformamide, dimethylacetamide, N-methylpyrrolidone and dimethylsulfoxide.
Aqueous dispersion polyurethane can also be produced from a polyurethane composition containing the polycarbonate polyol of the present invention, polydiisocyanate, and the chain extender.

<2-7. Polyurethane manufacturing method>
As a method for producing the polyurethane of the present invention using the above-mentioned reaction agent, production methods generally used experimentally or industrially can be used.
Examples thereof include the polycarbonate polyol of the present invention, polyols other than the polycarbonate polyol of the present invention that are used as necessary (hereinafter sometimes referred to as "other polyols"), polyisocyanate and a chain extender. A method of mixing and reacting (hereinafter sometimes referred to as a "one-step method"), or a method in which the polycarbonate polyol of the present invention, other polyols and polyisocyanate are first reacted to prepare a prepolymer having isocyanate groups at both ends. , a method of reacting the prepolymer with a chain extender (hereinafter sometimes referred to as a “two-step method”), and the like.

In the two-step method, the polycarbonate polyol of the present invention and other polyols are preliminarily reacted with one or more equivalents of polyisocyanate to prepare isocyanate intermediates at both ends corresponding to the soft segment of polyurethane. is. In this way, if the prepolymer is once prepared and then reacted with a chain extender, it may be easier to adjust the molecular weight of the soft segment portion, and it is useful when it is necessary to ensure phase separation between the soft segment and the hard segment. is useful.

<2-8. Single stage method>
The one-step method, which is also called a one-shot method, is a method in which the polycarbonate polyol of the present invention, other polyols, polyisocyanate and chain extender are charged all at once to carry out the reaction.

The amount of polyisocyanate used in the one-step method is not particularly limited, but when the sum of the total number of hydroxyl groups of the polycarbonate polyol of the present invention and other polyols, the number of hydroxyl groups and the number of amino groups of the chain extender is 1 equivalent , the lower limit is preferably 0.5 equivalents, more preferably 0.6 equivalents, more preferably 0.7 equivalents, particularly preferably 0.8 equivalents, and the upper limit is preferably 2.0 equivalents, more preferably 1.5 equivalents, more preferably 1.2 equivalents, particularly preferably 1.0 equivalents.
The equivalent ratio of the total number of isocyanate groups, total hydroxyl groups and total amino groups derived from the raw materials used is sometimes referred to as the NCO/OH ratio.

If the amount of polyisocyanate used is too large, unreacted isocyanate groups will cause side reactions, and the viscosity of the resulting polyurethane will tend to be too high, making handling difficult and flexibility likely to be impaired. If it is too large, the molecular weight of the polyurethane will not be sufficiently large, and there will be a tendency that the strength and solvent resistance of the polyurethane will not be sufficiently obtained.

The amount of the chain extender used is not particularly limited, but when the number obtained by subtracting the total number of hydroxyl groups of the polycarbonate polyol of the present invention and other polyols from the number of isocyanate groups of the polyisocyanate is 1 equivalent, the lower limit is preferably 0.7 equivalents, more preferably 0.8 equivalents, more preferably 0.9 equivalents, particularly preferably 0.95 equivalents, the upper limit is preferably 3.0 equivalents, more preferably 2.0 equivalents, still more preferably is 1.5 equivalents, particularly preferably 1.1 equivalents. If the amount of chain extender used is too large, the resulting polyurethane tends to be difficult to dissolve in the solvent and processing becomes difficult. In some cases, retention performance cannot be obtained, and in some cases, heat resistance deteriorates.

<2-9. Two-step method>
The two-step method, also called a prepolymer method, mainly includes the following methods.
(a) The polycarbonate polyol and other polyols of the present invention and excess polyisocyanate are added in advance so that the reaction equivalent ratio of polyisocyanate/(polycarbonate polyol and other polyols of the present invention) exceeds 1 to 10.0. to produce a prepolymer having an isocyanate group at the molecular chain end, and then adding a chain extender thereto to produce a polyurethane.
(b) a polyisocyanate and an excess of the polycarbonate polyol and other polyols of the present invention are preliminarily prepared so that the reaction equivalent ratio of polyisocyanate/(polycarbonate polyol and other polyol of the present invention) is 0.1 or more to less than 1.0; to produce a prepolymer having a hydroxyl group at the molecular chain end, and then reacting this with a polyisocyanate having an isocyanate group at the end as a chain extender to produce a polyurethane.

The two-step method can be carried out without solvent or in the presence of solvent.
Polyurethane production by the two-step method can be carried out by any one of the methods (1) to (3) described below.
(1) Without using a solvent, the polyisocyanate, the polycarbonate polyol of the present invention, and other polyols are directly reacted to synthesize a prepolymer, which is used as it is for the chain extension reaction.
(2) A prepolymer is synthesized by the method of (1), then dissolved in a solvent and used for subsequent chain extension reaction.
(3) Using a solvent from the beginning, the polyisocyanate, the polycarbonate polyol of the present invention, and other polyols are reacted, and then the chain extension reaction is carried out.

In the case of the method (1), in the chain extension reaction, the chain extension agent is dissolved in the solvent, or the prepolymer and the chain extension agent are dissolved in the solvent at the same time. It is important to obtain

The amount of polyisocyanate used in the two-step method (a) is not particularly limited, but the number of isocyanate groups when the total number of hydroxyl groups of the polycarbonate polyol of the present invention and other polyols is 1 equivalent is the lower limit of is preferably more than 1.0 equivalents, more preferably 1.2 equivalents, more preferably 1.5 equivalents, and the upper limit is preferably 10.0 equivalents, more preferably 5.0 equivalents, more preferably 3 .0 equivalent range.

If the amount of isocyanate used is too large, the excessive isocyanate groups tend to cause side reactions, making it difficult to achieve the desired physical properties of the polyurethane. may become less viable.

The amount of the chain extender used is not particularly limited, but the lower limit is preferably 0.1 equivalents, more preferably 0.5 equivalents, and still more preferably 0 equivalents per equivalent of the number of isocyanate groups contained in the prepolymer. 0.8 equivalents, and the upper limit is preferably 5.0 equivalents, more preferably 3.0 equivalents, still more preferably 2.0 equivalents.

For the purpose of adjusting the molecular weight, monofunctional organic amines and alcohols may coexist during the chain extension reaction.

In the two-step method (b), the amount of polyisocyanate to be used when preparing a prepolymer having a hydroxyl group at the end is not particularly limited. As the number of isocyanate groups when the 0.98 equivalents, more preferably 0.97 equivalents.

If the amount of isocyanate used is too small, the subsequent chain elongation reaction takes a long time to obtain the desired molecular weight, and production efficiency tends to decrease. It may decrease, or handling may be bad and productivity may be inferior.

The amount of the chain extender used is not particularly limited, but when the total number of hydroxyl groups of the polycarbonate polyol and other polyols used in the prepolymer is 1 equivalent, the total equivalent of the isocyanate group used in the prepolymer is added. As, the lower limit is preferably 0.7 equivalents, more preferably 0.8 equivalents, more preferably 0.9 equivalents, the upper limit is preferably less than 1.0 equivalents, more preferably 0.99 equivalents, more preferably It is in the range of 0.98 equivalents.

For the purpose of adjusting the molecular weight, monofunctional organic amines and alcohols may coexist during the chain extension reaction.

The chain extension reaction is usually carried out at 0° C. to 250° C., but this temperature varies depending on the amount of solvent, reactivity of raw materials used, reaction equipment, etc., and is not particularly limited. If the temperature is too low, the progress of the reaction may be slowed down, and the production time may be prolonged due to the low solubility of the raw materials and polymers. . The chain extension reaction may be performed under reduced pressure while defoaming.

Moreover, a catalyst, a stabilizer, etc. can also be added to a chain extension reaction as needed.
Examples of the catalyst include compounds such as triethylamine, tributylamine, dibutyltin dilaurate, stannous octoate, acetic acid, phosphoric acid, sulfuric acid, hydrochloric acid, and sulfonic acid. They may be used together. Examples of stabilizers include 2,6-dibutyl-4-methylphenol, distearylthiodipropionate, N,N'-di-2-naphthyl-1,4-phenylenediamine, tris(dinonylphenyl)phosphite, and the like. and may be used singly or in combination of two or more. When the chain extender is highly reactive such as a short-chain aliphatic amine, the reaction may be carried out without adding a catalyst.

<2-10. Aqueous polyurethane emulsion>
It is also possible to produce aqueous polyurethane emulsions using the polycarbonate polyols of the present invention.

In that case, a compound having at least one hydrophilic functional group and at least two isocyanate-reactive groups is used in reacting a polyol, including the polycarbonate polyols of the present invention, with an excess of polyisocyanate to produce a prepolymer. A prepolymer is formed by mixing, and an aqueous polyurethane emulsion is obtained through a process of neutralization and chlorination of hydrophilic functional groups, an emulsification process by adding water, and a chain extension reaction process.

The hydrophilic functional group of the compound having at least one hydrophilic functional group and at least two isocyanate-reactive groups used herein is, for example, a carboxyl group or a sulfonic acid group, which can be neutralized with an alkaline group. It is a base. In addition, the isocyanate-reactive group is a group that generally reacts with isocyanate to form a urethane bond or a urea bond, such as a hydroxyl group, a primary amino group, or a secondary amino group. It doesn't matter if you are.

Specific examples of compounds having at least one hydrophilic functional group and at least two isocyanate-reactive groups include 2,2′-dimethylolpropionic acid, 2,2-methylolbutyric acid, 2,2′ - dimethylol valeric acid and the like. Also included are diaminocarboxylic acids such as lysine, cystine, 3,5-diaminocarboxylic acid and the like. These may be used individually by 1 type, and may use 2 or more types together. When these are actually used, they are neutralized with amines such as trimethylamine, triethylamine, tri-n-propylamine, tributylamine and triethanolamine, and alkaline compounds such as sodium hydroxide, potassium hydroxide and ammonia. be able to.

When producing a water-based polyurethane emulsion, the amount of the compound having at least one hydrophilic functional group and at least two isocyanate-reactive groups should be adjusted to increase the dispersibility in water. It is preferably 1% by weight, more preferably 5% by weight, and still more preferably 10% by weight based on the total weight of polycarbonate polyol and other polyols. On the other hand, if too much is added, the properties of the polycarbonate polyol of the present invention may not be maintained, so the upper limit is preferably 50% by weight, more preferably 40% by weight, and still more preferably 30% by weight. is.

When producing an aqueous polyurethane emulsion, the reaction may be carried out in the presence of a solvent such as methyl ethyl ketone, acetone, or N-methyl-2-pyrrolidone in the prepolymer step, or may be carried out without a solvent. Moreover, when using a solvent, it is preferable to distill off the solvent by distillation after manufacturing an aqueous emulsion.

When the polycarbonate polyol of the present invention is used as a raw material to produce an aqueous polyurethane emulsion without solvent, the upper limit of the number average molecular weight obtained from the hydroxyl value of the polycarbonate polyol is preferably 5000, more preferably 4500, and still more preferably 4000. . Also, the lower limit of the number average molecular weight is preferably 300, more preferably 500, still more preferably 800. If the number average molecular weight obtained from the hydroxyl value exceeds 5000 or is smaller than 300, emulsification may become difficult.

Anionic surfactants typified by higher fatty acids, resin acids, acidic fatty alcohols, sulfate esters, higher alkyl sulfonates, alkylaryl sulfonates, sulfonated castor oil, sulfosuccinates, etc. for the synthesis or storage of aqueous polyurethane emulsions. , primary amine salts, secondary amine salts, tertiary amine salts, quaternary amine salts, cationic surfactants such as pyridinium salts, or known mixtures of ethylene oxide and long-chain fatty alcohols or phenols A nonionic surfactant or the like represented by the reaction product may be used in combination to maintain emulsion stability.

In addition, when making a water-based polyurethane emulsion, water is mechanically mixed under high shear in the presence of an emulsifier with an organic solvent solution of the prepolymer, if necessary, without the neutralization and chlorination step, to produce the emulsion. You can also

The water-based polyurethane emulsion thus produced can be used for various purposes. In particular, there is a recent demand for chemical raw materials with less environmental impact, and it is possible to replace conventional products for the purpose of not using organic solvents.

Specific uses of water-based polyurethane emulsions include, for example, coating agents, water-based paints, adhesives, synthetic leathers, and artificial leathers. In particular, the water-based polyurethane emulsion produced using the polycarbonate polyol of the present invention is flexible and effective as a coating agent, etc., because it has a structural unit derived from oxyalkylene glycol (A1) in the polycarbonate polyol. It is possible to use

<2-11. Additive>
Polyurethanes of the present invention produced using the polycarbonate polyols of the present invention contain heat stabilizers, light stabilizers, colorants, fillers, stabilizers, UV absorbers, antioxidants, antiblocking agents, flame retardants, anti-aging agents. Various additives such as inhibitors and inorganic fillers can be added and mixed within limits that do not impair the properties of the polyurethane of the present invention.

Compounds that can be used as heat stabilizers include phosphoric acid, aliphatic, aromatic or alkyl-substituted aromatic esters of phosphorous acid, hypophosphorous acid derivatives, phenylphosphonic acid, phenylphosphinic acid, diphenylphosphonic acid, polyphosphonates, dialkyl Phosphorus compounds such as pentaerythritol diphosphite and dialkylbisphenol A diphosphite; phenol derivatives, especially hindered phenol compounds; Compounds containing sulfur; tin-based compounds such as tin malate, dibutyltin monoxide, and the like can be used.

Specific examples of hindered phenol compounds include "Irganox1010" (trade name: manufactured by BASF Japan Ltd.), "Irganox1520" (trade name: manufactured by BASF Japan Ltd.), "Irganox245" (trade name: manufactured by BASF Japan Ltd.). ) and the like.
Phosphorus compounds include "PEP-36", "PEP-24G", "HP-10" (all trade names: manufactured by ADEKA Corporation), "Irgafos 168" (manufactured by BASF Japan Ltd.), etc. are mentioned.
Specific examples of sulfur-containing compounds include thioether compounds such as dilaurylthiopropionate (DLTP) and distearylthiopropionate (DSTP).

Examples of light stabilizers include benzotriazole-based compounds and benzophenone-based compounds. ”, “SANOL LS-765” (manufactured by Sankyo Co., Ltd.) and the like can be used.

Examples of ultraviolet absorbers include "TINUVIN328" and "TINUVIN234" (manufactured by Ciba Specialty Chemicals Co., Ltd.).

Colorants include dyes such as direct dyes, acid dyes, basic dyes and metal complex dyes; inorganic pigments such as carbon black, titanium oxide, zinc oxide, iron oxide and mica; Organic pigments such as anthraquinone-based, thioindigo-based, dioxazone-based, and phthalocyanine-based pigments can be used.

Examples of inorganic fillers include short glass fibers, carbon fibers, alumina, talc, graphite, melamine, and clay.

Examples of flame retardants include additive and reactive flame retardants such as phosphorous and halogen containing organic compounds, bromine or chlorine containing organic compounds, ammonium polyphosphate, aluminum hydroxide, antimony oxide and the like.

These additives may be used alone, or two or more of them may be used in any combination and ratio.

As for the amount of these additives added, the lower limit is preferably 0.01% by weight, more preferably 0.05% by weight, and still more preferably 0.1% by weight, and the upper limit is preferably 10% by weight, as a weight ratio to polyurethane. % by weight, more preferably 5% by weight, and even more preferably 1% by weight. If the amount of the additive added is too small, the effect of addition cannot be sufficiently obtained, and if it is too large, it may precipitate in the polyurethane or cause turbidity.

<2-12. Polyurethane film/polyurethane plate>
When the polyurethane of the present invention is used to produce a film, the lower limit of the film thickness is preferably 10 μm, more preferably 20 μm, still more preferably 30 μm, and the upper limit is preferably 1000 μm, more preferably 500 μm, and even more preferably. is 100 μm.
If the thickness of the film is too thick, there is a tendency that sufficient moisture permeability cannot be obtained.

<2-13. Molecular weight>
The molecular weight of the polyurethane of the present invention is appropriately adjusted according to its use, and is not particularly limited. and more preferably 100,000 to 300,000. If Mw is less than the above lower limit, sufficient strength and hardness may not be obtained. In particular, by using the polycarbonate polyol of the present invention, a polyurethane having an Mw of 100,000 or more can be easily produced due to its excellent reactivity, and sufficient mechanical strength can be obtained.

<2-14. Solvent resistance>
<2-14-1. Olein resistance>
The polyurethane of the present invention can be evaluated, for example, by the method described in the Examples section below, as a rate of change in the weight of the polyurethane test piece after immersion in oleic acid with respect to the weight of the polyurethane test piece before immersion in oleic acid. (%) is preferably 20% or less, more preferably 10% or less, still more preferably 5% or less, particularly preferably 4% or less, and most preferably 3% or less.
If the weight change rate exceeds the above upper limit, sufficient oleic acid resistance may not be obtained.

<2-14-2. Ethanol resistance>
The polyurethane of the present invention can be evaluated, for example, by the method described in the Examples section below, with respect to the weight of the polyurethane test piece before immersion in ethanol, the weight change rate (%) of the polyurethane test piece after immersion in ethanol ) is preferably 20% or less, more preferably 18% or less, still more preferably 15% or less, particularly preferably 10% or less, most preferably 8% or less.
If the weight change rate exceeds the above upper limit, sufficient ethanol resistance may not be obtained.

<2-14-3. Ethyl acetate resistance>
The polyurethane of the present invention can be evaluated, for example, by the method described in the Examples section below, as a rate of change in the weight of the polyurethane test piece after immersion in the chemical with respect to the weight of the polyurethane test piece before immersion in ethyl acetate ( %) is preferably 50% or less, more preferably 40% or less, and even more preferably 35% or less.
If the weight change rate exceeds the above upper limit, desired chemical resistance may not be obtained.

<2-15. Tensile elongation at break>
The polyurethane of the present invention was measured on a strip-shaped sample with a width of 10 mm, a length of 100 mm, and a thickness of about 50 to 100 μm at a chuck distance of 50 mm and a tensile speed of 500 mm/min at a temperature of 23° C. and a relative humidity of 50%. It is preferable that the tensile elongation at break and the breaking strength are within the following ranges.
That is, the lower limit of breaking elongation is preferably 150%, more preferably 200%, still more preferably 300%, and the upper limit is preferably 3000%, more preferably 2000%, and still more preferably 1500%. If the elongation at break is less than the above lower limit, there is a tendency to impair handleability such as workability, and if it exceeds the above upper limit, sufficient solvent resistance may not be obtained.
In addition, the lower limit of breaking strength is preferably 1.0 MPa, more preferably 2.0 MPa, more preferably 3.0 MPa, and the upper limit is preferably 100 MPa, more preferably 8.0 MPa, further preferably 6.0 MPa. . If the breaking strength is less than the above lower limit, the handling property such as processability tends to be impaired, and if it exceeds the above upper limit, the flexibility may be impaired.

<2-16.100%/300% modulus>
The polyurethane of the present invention is prepared by a one-stage process under the condition that the total amount of 4,4'-diphenylmethane diisocyanate and 1,4-butanediol is 17 to 20% by weight based on the total amount of polyurethane in the polycarbonate polyol of the present invention. When the polyurethane was obtained by the reaction, a strip-shaped sample with a width of 10 mm, a length of 100 mm, and a thickness of about 50 to 100 μm was measured at a chuck distance of 50 mm and a tensile speed of 500 mm/min at a temperature of 23° C. and a relative humidity of 50. The 100% modulus and 300% modulus measured in % are preferably in the following ranges.
That is, the 100% modulus preferably has a lower limit of 0.7 MPa, more preferably 0.9 MPa, and still more preferably 1.0 MPa, and an upper limit of preferably 20 MPa, more preferably 10 MPa, and still more preferably 5.0 MPa. . If the 100% modulus is less than the above lower limit, the solvent resistance may be insufficient, and if it exceeds the above upper limit, flexibility tends to be insufficient, and handling properties such as workability tend to be impaired.
The 300% modulus preferably has a lower limit of 1.4 MPa, more preferably 2.0 MPa, and still more preferably 2.5 MPa, and an upper limit of preferably 15 MPa, more preferably 9.0 MPa, and still more preferably 6.0 MPa. is. If the 300% modulus is less than the above lower limit, the solvent resistance may not be sufficient, and if it exceeds the above upper limit, the flexibility tends to be insufficient, and the handleability such as workability tends to be impaired.

<2-17. Glass transition temperature>
The lower limit of the glass transition temperature of the polyurethane of the present invention is usually -70°C or higher, preferably -60°C or higher, more preferably -50°C or higher, and further preferably -40°C or higher. A temperature of -30°C or higher is particularly preferred. The upper limit is usually 0°C or lower, preferably -5°C or lower, more preferably -10°C or lower, even more preferably -15°C or lower, and -20°C or lower. is particularly preferred. When the glass transition temperature of the polyurethane is at least the above lower limit, the solvent resistance is good, and when it is at most the above upper limit, hardening at low temperatures can be prevented, and touch feeling tends to be improved.

<2-18. Application>
Since the polyurethane of the present invention has excellent solvent resistance and good flexibility and mechanical strength, it can be used for foams, elastomers, elastic fibers, paints, fibers, pressure-sensitive adhesives, adhesives, flooring materials, sealants, medical materials, It can be widely used for artificial leather, synthetic leather, coating agents, water-based polyurethane coatings, active energy ray-curable polymer compositions, and the like.

In particular, when the polyurethane of the present invention is used in applications such as artificial leather, synthetic leather, water-based polyurethane, adhesives, elastic fibers, medical materials, flooring materials, paints, and coating agents, solvent resistance, flexibility, and mechanical strength are improved. Because it has a good balance of A good characteristic of being strong can be imparted. Moreover, it can be suitably used for automobile applications where heat resistance is required and outdoor applications where weather resistance is required.

The polyurethanes of the invention can be used in cast polyurethane elastomers. Specific applications include rolling rolls, paper manufacturing rolls, office equipment, rolls such as pretension rolls, solid tires for forklifts, automobile vehicle nutrams, trolleys, trucks, casters, etc. Industrial products include conveyor belt idlers and guides. Rolls, pulleys, steel pipe linings, ore rubber screens, gears, connection rings, liners, pump impellers, cyclone cones, cyclone liners, etc. It can also be used for OA equipment belts, paper feed rolls, copying cleaning blades, snow plows, toothed belts, surf rollers and the like.

The polyurethanes of the invention also find application as thermoplastic elastomers. For example, it can be used for tubes and hoses, spiral tubes, fire hoses, etc. in pneumatic equipment used in the food and medical fields, coating equipment, analytical equipment, physical and chemical equipment, metering pumps, water treatment equipment, industrial robots, and the like. In addition, it is used as a belt such as a round belt, a V belt, a flat belt, etc. in various transmission mechanisms, spinning machines, packing machines, printing machines, and the like. It can also be used for heel tops and soles of footwear, couplings, packings, pole joints, bushes, gears, machine parts such as rolls, sporting goods, leisure goods, watch belts and the like. Automobile parts include oil stoppers, gearboxes, spacers, chassis parts, interior parts, and tire chain substitutes. Also, it can be used for films such as keyboard films and films for automobiles, curled cords, cable sheaths, bellows, conveyor belts, flexible containers, binders, synthetic leathers, dipping products, adhesives and the like.

The polyurethane of the present invention can also be applied as a solvent-based two-component paint, and can be applied to wood products such as musical instruments, Buddhist altars, furniture, decorative plywood, and sporting goods. It can also be used for automobile repair as tar epoxy urethane.

The polyurethane of the present invention can be used as a component of moisture-curable one-pack paints, blocked isocyanate-based solvent paints, alkyd resin paints, urethane-modified synthetic resin paints, ultraviolet-curable paints, water-based urethane paints, and the like. Paints for plastic bumpers, strippable paints, coating agents for magnetic tapes, overprint varnishes for floor tiles, flooring materials, paper, wood grain printing films, etc., varnishes for wood, coil coats for high processing, optical fiber protective coatings, solder resists, metals It can be applied to printing top coats, vapor deposition base coats, white coats for food cans, and the like.

The polyurethane of the present invention can also be applied as a pressure-sensitive adhesive or adhesive to food packaging, shoes, footwear, magnetic tape binders, decorative paper, wood, structural members, and the like. can also be used.

The polyurethane of the present invention can be used as a binder for magnetic recording media, inks, castings, baked bricks, graft materials, microcapsules, granular fertilizers, granular pesticides, polymer cement mortar, resin mortar, rubber chip binders, recycled foams, glass fiber sizing, and the like. Available.

The polyurethane of the present invention can be used as a component of a fiber processing agent for shrink-proofing, wrinkle-proofing, water-repellent finishing, and the like.
When the polyurethane of the present invention is used as an elastic fiber, the fiberization method is not particularly limited as long as it can be spun. For example, a melt spinning method can be employed in which the material is pelletized, melted, and spun directly through a spinneret. When the elastic fiber is obtained from the polyurethane of the present invention by melt spinning, the spinning temperature is preferably 250°C or lower, more preferably 200°C or higher and 235°C or lower.

The polyurethane elastic fiber of the present invention can be used as it is as a bare yarn, or can be covered with other fibers and used as a covered yarn. Examples of other fibers include conventionally known fibers such as polyamide fibers, wool, cotton and polyester fibers, among which polyester fibers are preferably used in the present invention. Further, the polyurethane elastic fiber of the present invention may contain a dyeing type disperse dye.

The polyurethane of the present invention can be used as a sealant and caulking for concrete rammed walls, induced joints, around sashes, wall-type PC (Precast Concrete) joints, ALC (Autoclaved Light-weight Concrete) joints, board joints, composite glass sealants, It can be used for insulating sash sealants, automotive sealants, etc.

The polyurethane of the present invention can be used as a medical material, including blood compatible materials such as tubes, catheters, artificial hearts, artificial blood vessels, and artificial valves, and disposable materials such as catheters, tubes, bags, and surgical gloves. , artificial kidney potting materials, etc.
By modifying the terminal of the polyurethane of the present invention, it can be used as a raw material for UV curable coatings, electron beam curable coatings, photosensitive resin compositions for flexographic printing plates, photocurable optical fiber coating compositions, and the like. can.

<2-19. Urethane (meth)acrylate oligomer>
A urethane (meth)acrylate oligomer can be produced by subjecting the polycarbonate polyol of the present invention to an addition reaction between a polyisocyanate and a hydroxyalkyl (meth)acrylate. When other raw material compounds such as a polyol and a chain extender are used in combination, the urethane (meth)acrylate oligomer can be produced by subjecting the polyisocyanate to an addition reaction with these other raw material compounds. .
In the present invention, the expression "(meth)acryl" such as (meth)acrylate or (meth)acrylic acid means acryl and/or methacryl.

In addition, the charging ratio of each raw material compound at that time is substantially the same as or the same as the composition of the desired urethane (meth)acrylate oligomer.
The amount of all isocyanate groups in the urethane (meth)acrylate oligomer and the amount of all functional groups that react with isocyanate groups such as hydroxyl groups and amino groups are usually theoretically equimolar.

When producing a urethane (meth)acrylate-based oligomer, the amount of hydroxyalkyl (meth)acrylate used is adjusted to the amount of hydroxyalkyl (meth)acrylate, polycarbonate polyol, and other raw material compounds used as needed, such as polyol and Usually 10 mol% or more, preferably 15 mol% or more, more preferably 25 mol% or more, and usually 70 mol% or less, preferably 50 mol%, relative to the total amount of the compound containing a functional group that reacts with isocyanate such as a chain extender. % or less. The molecular weight of the resulting urethane (meth)acrylate oligomer can be controlled according to this ratio. When the proportion of hydroxyalkyl (meth)acrylate is large, the molecular weight of the urethane (meth)acrylate oligomer tends to be small, and when the proportion is small, the molecular weight tends to be large.

The amount of polycarbonate polyol used is preferably 25 mol % or more, more preferably 50 mol % or more, and still more preferably 70 mol % or more, based on the total amount of polycarbonate polyol and polyol used. When the amount of the polycarbonate polyol used is at least the above lower limit, the resulting cured product tends to have good hardness and stain resistance, which is preferable.

The amount of polycarbonate polyol used is preferably 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more, and particularly preferably 50% by weight or more, based on the total amount of polycarbonate polyol and polyol used. is 70% by weight or more. When the amount of the polycarbonate polyol used is at least the above lower limit, the viscosity of the obtained composition is lowered and workability is improved, and the mechanical strength, hardness and abrasion resistance of the obtained cured product tend to be improved. It is preferable.

Furthermore, the amount of polycarbonate polyol used is preferably 25 mol % or more, more preferably 50 mol % or more, and still more preferably 70 mol % or more, relative to the total amount of polycarbonate polyol and polyol used. When the amount of the polycarbonate polyol used is at least the above lower limit, elongation and weather resistance of the resulting cured product tend to be improved, which is preferable.

Furthermore, when a chain extender is used, the amount of the polyol used is preferably 70 mol% or more, more preferably 80 mol%, relative to the total amount of the compound used, which is the combination of the polycarbonate polyol and the polyol and the chain extender. Above, more preferably 90 mol % or more, particularly preferably 95 mol % or more. When the amount of polyol is at least the above lower limit, the liquid stability tends to be improved, which is preferable.

A solvent can be used for the purpose of adjusting the viscosity during the production of the urethane (meth)acrylate oligomer. A solvent may be used individually by 1 type, and may be used in mixture of 2 or more types. Any known solvent can be used as the solvent. Preferred solvents include toluene, xylene, ethyl acetate, butyl acetate, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, and the like. The solvent can be used in an amount of less than 300 parts by weight per 100 parts by weight of solids in the reaction system.

In the production of the urethane (meth)acrylate oligomer, the total content of the produced urethane (meth)acrylate oligomer and its raw material compound is preferably 20% by weight or more, preferably 40% by weight, based on the total amount of the reaction system. % or more is more preferable. The upper limit of this total content is 100% by weight. When the total content of the urethane (meth)acrylate-based oligomer and its raw material compounds is 20% by weight or more, the reaction rate tends to be high and the production efficiency tends to be improved, which is preferable.

An addition reaction catalyst can be used in the production of the urethane (meth)acrylate oligomer. Examples of the addition reaction catalyst include dibutyltin laurate, dibutyltin dioctate, dioctyltin dilaurate, and dioctyltin dioctate. The addition reaction catalyst may be used alone or in combination of two or more. Among these, the addition reaction catalyst is preferably dioctyltin dilaurate from the viewpoint of environmental adaptability, catalytic activity, and storage stability.

The addition reaction catalyst has an upper limit of usually 1000 ppm by weight, preferably 500 ppm by weight, and a lower limit of usually 10 ppm by weight, preferably Used at 30 ppm by weight.

Moreover, when a (meth)acryloyl group is included in the reaction system during the production of the urethane (meth)acrylate oligomer, a polymerization inhibitor can be used in combination. Examples of such polymerization inhibitors include phenols such as hydroquinone, methylhydroquinone, hydroquinone monoethyl ether and dibutylhydroxytoluene; amines such as phenothiazine and diphenylamine; copper salts such as copper dibutyldithiocarbamate; Salts, nitro compounds, nitroso compounds and the like are included. A polymerization inhibitor may be used individually by 1 type, and may be used in mixture of 2 or more types. Among these, the polymerization inhibitor is preferably a phenol.

The polymerization inhibitor has an upper limit of usually 3000 ppm, preferably 1000 ppm by weight, particularly preferably 500 ppm by weight, and a lower limit of It is usually used at 50 weight ppm, preferably 100 weight ppm.

During the production of the urethane (meth)acrylate oligomer, the reaction temperature is usually 20° C. or higher, preferably 40° C. or higher, more preferably 60° C. or higher. A reaction temperature of 20° C. or higher is preferable because the reaction rate tends to increase and the production efficiency tends to improve. Moreover, the reaction temperature is usually 120° C. or lower, preferably 100° C. or lower. When the reaction temperature is 120° C. or lower, it is preferable because side reactions such as allophanate reaction are less likely to occur. Further, when the reaction system contains a solvent, the reaction temperature is preferably below the boiling point of the solvent, and when (meth)acrylate is contained, it is 70 ° C. from the viewpoint of preventing the reaction of the (meth)acryloyl group. The following are preferable. The reaction time is usually about 5 to 20 hours.

The number average molecular weight of the urethane (meth)acrylate oligomer thus obtained is preferably 500 or more, particularly preferably 1,000 or more, and preferably 10,000 or less, particularly preferably 5,000 or less, particularly preferably 3,000 or less. When the number average molecular weight of the urethane (meth)acrylate oligomer is at least the above lower limit, the three-dimensional processability of the resulting cured film is favorable, and the balance between the three-dimensional processability and stain resistance tends to be excellent, which is preferable. When the number average molecular weight of the urethane (meth)acrylate oligomer is equal to or less than the above upper limit, the cured film obtained from the composition has good stain resistance, and tends to have an excellent balance between suitability for three-dimensional processing and stain resistance. Therefore, it is preferable. This is because three-dimensional processing suitability and stain resistance depend on the distance between cross-linking points in the network structure. It is presumed that this is because the structure becomes a strong structure and is excellent in stain resistance.

<2-20. Polyester Elastomer>
The polycarbonate polyol of the present invention can be used as a polyester elastomer. Polyester-based elastomers are copolymers composed of hard segments mainly composed of aromatic polyesters and soft segments mainly composed of aliphatic polyethers, aliphatic polyesters or aliphatic polycarbonates. When the polycarbonate polyol of the present invention is used as a constituent component of the soft segment, physical properties such as heat resistance and water resistance are superior to those in which aliphatic polyethers and aliphatic polyesters are used. In addition, compared to known polycarbonate polyols, the resulting polycarbonate ester elastomer has a fluidity when melted, that is, a melt flow rate suitable for blow molding and extrusion molding, and has an excellent balance with mechanical strength and other physical properties. , fibers, films, sheets and other molding materials such as elastic yarns, boots, gears, tubes and packings. Specifically, it can be effectively applied to applications such as joint boots for automobiles, household appliance parts, etc., which require heat resistance and durability, and electric wire coating materials.

<2-21. Active energy ray-curable polymer composition>
An active energy ray-curable polymer composition containing the above urethane (meth)acrylate oligomer (hereinafter sometimes referred to as "the active energy ray-curable polymer composition of the present invention") will be described.
The active energy ray-curable polymer composition of the present invention preferably has a molecular weight between calculated network crosslink points of 500 to 10,000.

In the present specification, the calculated network cross-linking point molecular weight of the composition is the average molecular weight between the active energy ray-reactive groups (hereinafter sometimes referred to as "crosslinking points") forming the network structure in the entire composition. represents a value. The molecular weight between the calculated network cross-linking points has a correlation with the network area at the time of forming the network structure, and the larger the molecular weight between the calculated network cross-linking points, the smaller the cross-linking density. In the reaction by active energy ray curing, when a compound having only one active energy ray reactive group (hereinafter sometimes referred to as a "monofunctional compound") reacts, it becomes a linear polymer, while active energy A network structure is formed when a compound having two or more linear reactive groups (hereinafter sometimes referred to as a "polyfunctional compound") reacts.

Therefore, here, the active energy ray reactive group possessed by the polyfunctional compound is a cross-linking point, the calculation of the molecular weight between the calculated network cross-linking points is centered on the polyfunctional compound having the cross-linking point, and the monofunctional compound is possessed by the polyfunctional compound. The molecular weight between the cross-linking points is treated as having the effect of extending the molecular weight between the cross-linking points, and the molecular weight between the cross-linking points of the calculated network is calculated. Further, the calculation of the molecular weight between cross-linking points in the calculated network is performed on the assumption that all the active energy ray-reactive groups have the same reactivity and that all the active energy ray-reactive groups react with the irradiation of the active energy ray. .

In a polyfunctional compound single-system composition in which only one type of polyfunctional compound reacts, twice the average molecular weight per active energy ray-reactive group possessed by the polyfunctional compound is the molecular weight between the calculated network crosslink points. . For example, (1000/2)×2=1000 for a bifunctional compound with a molecular weight of 1,000, and (300/3)×2=200 for a trifunctional compound with a molecular weight of 300.
In a polyfunctional compound mixed system composition in which multiple types of polyfunctional compounds react, the average value of the molecular weight between the calculated network crosslink points of each of the above single systems with respect to the total number of active energy ray reactive groups contained in the composition is It is the molecular weight between the calculated network crosslink points of the composition. For example, in a composition comprising a mixture of 4 mols of a bifunctional compound with a molecular weight of 1,000 and 4 mols of a trifunctional compound with a molecular weight of 300, the total number of active energy ray-reactive groups in the composition is 2×4+3×4=20. and the calculated molecular weight between network crosslink points of the composition is {(1000/2)×8+(300/3)×12}×2/20=520.

When a monofunctional compound is included in the composition, a molecule formed by a molar equivalent to each of the active energy ray reactive groups (i.e., cross-linking points) of the polyfunctional compound and a monofunctional compound linked to the cross-linking points is calculated. Assuming that the reaction is located in the center of the chain, the amount of elongation of the molecular chain by the monofunctional compound at one cross-linking point is the total molecular weight of the monofunctional compound and the total active energy ray reaction of the polyfunctional compound in the composition. Half of the value divided by the base. Here, since the molecular weight between the calculated network cross-linking points is considered to be twice the average molecular weight per one cross-linking point, the amount extended by the monofunctional compound with respect to the calculated molecular weight between the calculated network cross-linking points for the polyfunctional compound is , is a value obtained by dividing the total molecular weight of monofunctional compounds by the total number of active energy ray-reactive groups of polyfunctional compounds in the composition.

For example, in a composition comprising a mixture of 40 mols of a monofunctional compound with a molecular weight of 100 and 4 mols of a bifunctional compound with a molecular weight of 1,000, the number of active energy ray reactive groups of the polyfunctional compound is 2×4=8. , the extension amount due to the monofunctional compound in the molecular weight between cross-linking points in the calculated network is 100×40/8=500. That is, the molecular weight between calculated network crosslink points of the composition is 1000+500=1500.
From the above, it can be seen that for a mixture of M _A moles of monofunctional compound of molecular weight W _A , M _B moles of f _B- functional compound of molecular weight W B, and M _C moles of f _{C -} functional compound of molecular weight W _C , the composition The molecular weight between calculated network cross-linking points of a compound can be expressed by the following formula.

The calculated molecular weight between network crosslink points of the active energy ray-curable polymer composition of the present invention calculated in this manner is preferably 500 or more, more preferably 800 or more, and 1,000 or more. more preferably 10,000 or less, more preferably 8,000 or less, even more preferably 6,000 or less, and even more preferably 4,000 or less , 3,000 or less.

When the molecular weight between calculated network cross-linking points is 10,000 or less, the cured film obtained from the composition has good stain resistance and tends to have an excellent balance between suitability for three-dimensional processing and stain resistance, which is preferable. Further, when the molecular weight between the cross-linking points of the calculated network is 500 or more, the three-dimensional processability of the resulting cured film becomes favorable, and the balance between the three-dimensional processability and stain resistance tends to be excellent, which is preferable. This is because three-dimensional processing suitability and stain resistance depend on the distance between cross-linking points in the network structure. It is presumed that this is because the structure becomes a strong structure and is excellent in stain resistance.

The active energy ray-curable polymer composition of the present invention may further contain components other than the urethane (meth)acrylate oligomer. Such other components include, for example, active energy ray-reactive monomers, active energy ray-curable oligomers, polymerization initiators, photosensitizers, additives, and solvents.

In the active energy ray-curable polymer composition of the present invention, the content of the urethane (meth)acrylate-based oligomer is 40% by weight or more based on the total amount of the active energy ray-reactive components including the urethane (meth)acrylate-based oligomer. and more preferably 60% by weight or more. The upper limit of this content is 100% by weight. When the content of the urethane (meth)acrylate oligomer is 40% by weight or more, the curability is improved, and the three-dimensional processability tends to be improved without excessively increasing the mechanical strength of the cured product. It is preferable because

In addition, in the active energy ray-curable polymer composition of the present invention, the content of the urethane (meth)acrylate oligomer is preferably large in terms of elongation and film-forming properties. In terms of points, the smaller the number, the better. From this point of view, the content of the urethane (meth)acrylate oligomer is preferably 50% by weight or more with respect to the total amount of all components including other components in addition to the active energy ray-reactive component. , more preferably 70% by weight or more. The upper limit of the content of the urethane (meth)acrylate oligomer is 100% by weight, and the content is preferably 100% by weight or less.

In addition, in the active energy ray-curable polymer composition of the present invention, the total content of the active energy ray-reactive components including the urethane (meth)acrylate-based oligomer affects the curing speed and surface curability of the composition. From the viewpoint of being excellent and leaving no tack, the content is preferably 60% by weight or more, more preferably 80% by weight or more, and even more preferably 90% by weight or more, based on the total amount of the composition. , 95% by weight or more. The upper limit of this content is 100% by weight.

Any known active energy ray-reactive monomer can be used as the active energy ray-reactive monomer. These active energy ray-reactive monomers are used for the purpose of adjusting the hydrophilicity and hydrophobicity of the urethane (meth)acrylate oligomer, and the physical properties such as the hardness and elongation of the cured product when the resulting composition is cured. be done. The active energy ray-reactive monomers may be used singly or in combination of two or more.

Examples of such active energy ray-reactive monomers include vinyl ethers, (meth)acrylamides, and (meth)acrylates, and specific examples include styrene, α-methylstyrene, α-chlorostyrene. , vinyltoluene, and divinylbenzene; vinyl acetate, vinyl butyrate, N-vinylformamide, N-vinylacetamide, N-vinyl-2-pyrrolidone, N-vinylcaprolactam, divinyl adipate, and other vinyl monomers Ester monomers; vinyl ethers such as ethyl vinyl ether and phenyl vinyl ether; allyl compounds such as diallyl phthalate, trimethylolpropane diallyl ether and allyl glycidyl ether; (meth)acrylamide, N,N-dimethylacrylamide, N,N-dimethylmethacryl Amide, N-methylol(meth)acrylamide, N-methoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, Nt-butyl(meth)acrylamide, (meth)acryloylmorpholine, methylenebis(meth)acrylamide, etc. (Meth) acrylamides; (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, -n-butyl (meth) acrylate, (meth) acrylic acid - i-butyl, t-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, (meth)acrylic acid Tetrahydrofurfuryl, morpholyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, glycidyl (meth)acrylate , dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, phenoxyethyl (meth)acrylate, tricyclodecane (meth)acrylate, ( meth)dicyclopentenyl acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentenyl (meth)acrylate, allyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, (meth)acrylate Monofunctional (meth)acrylates such as isobornyl acrylate and phenyl (meth)acrylate and ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate ( n = 5 to 14), propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, di(meth)acrylate polypropylene glycol acrylate (n = 5 to 14), 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, polybutylene glycol di(meth)acrylate ( n = 3 to 16), poly(1-methylbutylene glycol) di(meth)acrylate (n = 5 to 20), di(meth)acrylic acid-1,6-hexanediol, di(meth)acrylic acid- 1,9-nonanediol, neopentyl glycol di(meth)acrylate, neopentyl glycol hydroxypivalate di(meth)acrylate, dicyclopentanediol di(meth)acrylate, tricyclo di(meth)acrylate Decane, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta( meth)acrylate, dipentaerythritol hexa(meth)acrylate, trimethylolpropane trioxyethyl (meth)acrylate, trimethylolpropane trioxypropyl (meth)acrylate, trimethylolpropane polyoxyethyl (meth)acrylate, trimethylolpropane poly Oxypropyl (meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate di(meth)acrylate, ethylene oxide-added bisphenol A di(meth)acrylate, ethylene oxide addition bisphenol F di(meth)acrylate, propylene oxide addition bisphenol A di(meth)acrylate, propylene oxide addition bisphenol F di(meth)acrylate, tri polyfunctional (meth)acrylates such as cyclodecane dimethanol di(meth)acrylate, bisphenol A epoxy di(meth)acrylate, bisphenol F epoxy di(meth)acrylate;

Among these, in applications where coating properties are particularly required, (meth)acryloylmorpholine, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, (meth)acrylic acid Having a ring structure in the molecule, such as trimethylcyclohexyl, phenoxyethyl (meth)acrylate, tricyclodecane (meth)acrylate, dicyclopentenyl (meth)acrylate, isobornyl (meth)acrylate, (meth)acrylamide, etc. Monofunctional (meth)acrylates are preferred, and on the other hand, in applications where mechanical strength of the resulting cured product is required, di(meth)acrylic acid-1,4-butanediol, di(meth)acrylic acid-1, 6-Hexanediol, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol Polyfunctional (meth)acrylates such as tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate are preferred. .

In the active energy ray-curable polymer composition of the present invention, the content of the active energy ray-reactive monomer is determined from the viewpoint of adjusting the viscosity of the composition and adjusting physical properties such as hardness and elongation of the resulting cured product. It is preferably 50% by weight or less, more preferably 30% by weight or less, even more preferably 20% by weight or less, and particularly preferably 10% by weight or less, relative to the total amount of the composition.

The said active-energy-ray-curable oligomer may be used individually by 1 type, and may be used in mixture of 2 or more types. Examples of the active energy ray-curable oligomers include epoxy (meth)acrylate oligomers and acrylic (meth)acrylate oligomers.

In the active-energy-ray-curable polymer composition of the present invention, the content of the active-energy-ray-reactive oligomer should be , preferably 50% by weight or less, more preferably 30% by weight or less, even more preferably 20% by weight or less, and particularly preferably 10% by weight or less.

The polymerization initiator is mainly used for the purpose of improving the initiation efficiency of the polymerization reaction that proceeds upon exposure to active energy rays such as ultraviolet rays and electron beams. As the polymerization initiator, a radical photopolymerization initiator which is a compound having a property of generating radicals by light is generally used, and any known radical photopolymerization initiator can be used. One of the polymerization initiators may be used alone, or two or more of them may be used in combination. Furthermore, a photoradical polymerization initiator and a photosensitizer may be used in combination.

Examples of photoradical polymerization initiators include benzophenone, 2,4,6-trimethylbenzophenone, 4,4-bis(diethylamino)benzophenone, 4-phenylbenzophenone, methylorthobenzoylbenzoate, thioxanthone, diethylthioxanthone, isopropylthioxanthone, chloro Thioxanthone, 2-ethylanthraquinone, t-butylanthraquinone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 1-hydroxycyclohexylphenylketone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, methylbenzoylformate, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2,6-dimethylbenzoyldiphenylphosphine oxide, 2 , 4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and 2- Hydroxy-1-[4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl]-2-methyl-propan-1-one and the like.

Among these, benzophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 2,4,6 are preferred because the curing speed is fast and the crosslink density can be sufficiently increased. -trimethylbenzoyldiphenylphosphine oxide and 2-hydroxy-1-[4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl]-2-methyl-propan-1-one Preferably 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 2-hydroxy-1-[4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl ]-2-methyl-propan-1-one is more preferred.

Further, when the active energy ray-curable polymer composition contains a compound having a cationically polymerizable group such as an epoxy group together with a radically polymerizable group, as a polymerization initiator, a photocationic polymerization initiator is used together with the photoradical polymerization initiator described above. A polymerization initiator may be included. Any known photocationic polymerization initiator can be used.

The content of these polymerization initiators in the active energy ray-curable polymer composition of the present invention is preferably 10 parts by weight or less with respect to a total of 100 parts by weight of the active energy ray-reactive components. It is more preferably 5 parts by weight or less. When the content of the polymerization initiator is 10 parts by weight or less, the mechanical strength is less likely to be lowered by decomposition products of the initiator, which is preferable.

The photosensitizer can be used for the same purpose as the polymerization initiator. The photosensitizers may be used singly or in combination of two or more. As the photosensitizer, any known photosensitizer can be used as long as the effect of the present invention can be obtained. Examples of such photosensitizers include ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, amyl 4-dimethylaminobenzoate, and 4-dimethylaminoacetophenone.

In the active energy ray-curable polymer composition of the present invention, the content of the photosensitizer is preferably 10 parts by weight or less with respect to a total of 100 parts by weight of the active energy ray-reactive components. , 5 parts by weight or less. When the content of the photosensitizer is 10 parts by weight or less, the mechanical strength is less likely to decrease due to the decrease in the crosslink density, which is preferable.

The additive is optional, and various materials added to compositions used for similar purposes can be used as additives. Additives may be used singly or in combination of two or more. Examples of such additives include glass fibers, glass beads, silica, alumina, calcium carbonate, mica, zinc oxide, titanium oxide, mica, talc, kaolin, metal oxides, metal fibers, iron, lead, and metal powders. fillers such as; carbon fibers, carbon black, graphite, carbon nanotubes, carbon materials such as fullerenes such as C60 (fillers and carbon materials may be collectively referred to as "inorganic components"); antioxidant agent, heat stabilizer, ultraviolet absorber, HALS (hindered amine light stabilizer), anti-fingerprint agent, surface hydrophilizing agent, antistatic agent, slip agent, plasticizer, release agent, antifoaming agent, leveling agent, Anti-settling agents, surfactants, thixotropic agents, lubricants, flame retardants, flame retardant aids, polymerization inhibitors, fillers, modifiers such as silane coupling agents; coloring agents such as pigments, dyes, and hue modifiers agents; and monomers and/or oligomers thereof, or curing agents, catalysts, curing accelerators necessary for synthesizing inorganic components; and the like.

In the active energy ray-curable polymer composition of the present invention, the content of the additive is preferably 10 parts by weight or less with respect to a total of 100 parts by weight of the active energy ray-reactive components. It is more preferably not more than parts by weight. When the content of the additive is 10 parts by weight or less, the mechanical strength is less likely to decrease due to the decrease in crosslink density, which is preferable.

The solvent is used for the purpose of adjusting the viscosity of the active energy ray-curable polymer composition of the present invention, depending on, for example, the coating method for forming the coating film of the active energy ray-curable polymer composition of the present invention. can be used. A solvent may be used individually by 1 type, and may mix and use 2 or more types. As the solvent, any known solvent can be used as long as the effects of the present invention can be obtained. Preferred solvents include toluene, xylene, ethyl acetate, butyl acetate, isopropanol, isobutanol, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, and the like. The solvent can usually be used in an amount of less than 200 parts by weight per 100 parts by weight of the solid content of the active energy ray-curable polymer composition.

There are no particular limitations on the method of adding optional components such as the above-described additives to the active energy ray-curable polymer composition of the present invention, and conventionally known mixing and dispersing methods can be used. In order to more reliably disperse the optional components, it is preferable to perform the dispersion treatment using a disperser. Specifically, for example, two-roll, three-roll, bead mill, ball mill, sand mill, pebble mill, tron mill, sand grinder, segvariator, planetary stirrer, high speed impeller disperser, high speed stone mill, high speed impact A method of treating with a mill, a kneader, a homogenizer, an ultrasonic disperser, or the like can be mentioned.

The viscosity of the active-energy-ray-curable polymer composition of the present invention can be appropriately adjusted according to the application, mode of use, etc. of the composition. Therefore, the viscosity at 25 ° C. in an E-type viscometer (rotor 1 ° 34 ′ × R24) is preferably 10 mPa s or more, more preferably 100 mPa s or more. It is preferably 000 mPa·s or less, more preferably 50,000 mPa·s or less. The viscosity of the active energy ray-curable polymer composition can be adjusted by, for example, the content of the above-mentioned urethane (meth)acrylate-based oligomer, the types of the above-mentioned optional components, their mixing ratios, and the like.

Examples of coating methods for the active energy ray-curable polymer composition of the present invention include a bar coater method, an applicator method, a curtain flow coater method, a roll coater method, a spray method, a gravure coater method, a comma coater method, and a reverse roll coater method. , a lip coater method, a die coater method, a slot die coater method, an air knife coater method, a dip coater method and the like can be applied, and among them, a bar coater method and a gravure coater method are preferable.

<2-22. Cured Film and Laminate>
The active energy ray-curable polymer composition of the present invention can be made into a cured film by irradiating it with an active energy ray.
Infrared rays, visible rays, ultraviolet rays, X rays, electron beams, α rays, β rays, γ rays, etc. can be used as the active energy rays used when curing the above composition. From the viewpoint of equipment cost and productivity, it is preferable to use electron beams or ultraviolet rays. Lasers, He--Cd lasers, solid-state lasers, xenon lamps, high-frequency induction mercury lamps, sunlight, etc. are suitable.

The irradiation dose of the active energy ray can be appropriately selected according to the type of the active energy ray. For example, in the case of curing by electron beam irradiation, the irradiation dose is preferably 1 to 10 Mrad. In the case of ultraviolet irradiation, it is preferably 50 to 1,000 mJ/cm ² . The atmosphere during curing may be air or an inert gas such as nitrogen or argon. Alternatively, irradiation may be performed in a closed space between the film or glass and the metal mold.

The thickness of the cured film can be appropriately determined according to the intended use, but the lower limit is preferably 1 μm, more preferably 3 μm, and particularly preferably 5 μm. The upper limit is preferably 200 µm, more preferably 100 µm, and particularly preferably 50 µm. When the film thickness is 1 μm or more, the appearance of design and functionality after three-dimensional processing is good, and on the other hand, when it is 200 μm or less, internal curability and suitability for three-dimensional processing are good, which is preferable. For industrial use, the lower limit of the film thickness of the cured film is preferably 1 µm, and the upper limit is preferably 100 µm, more preferably 50 µm, particularly preferably 20 µm, and most preferably 10 µm.

It is possible to obtain a laminate having a layer composed of the above cured film on a substrate. This laminate is not particularly limited as long as it has a layer composed of a cured film, and may have a layer other than the substrate and the cured film between the substrate and the cured film, or may have a layer other than the substrate and the cured film. may have. Moreover, the laminate may have a plurality of substrates and cured films.

As a method for obtaining a laminate having a cured film of multiple layers, there is a method in which all layers are laminated in an uncured state and then cured with active energy rays, and the lower layer is cured or semi-cured with active energy rays and then A known method is applied, such as a method of applying an upper layer and curing with active energy rays again, a method of applying each layer to a release film or a base film, and then bonding the layers together in an uncured or semi-cured state. Although it is possible, from the viewpoint of enhancing the adhesion between layers, a method of laminating in an uncured state and then curing with an active energy ray is preferable. As a method of laminating in an uncured state, a known method such as sequential coating in which the lower layer is applied and then the upper layer is applied, or simultaneous multilayer coating in which two or more layers are applied at the same time from multiple slits is applied. It is possible, but not limited to this.

Examples of substrates include polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyolefins such as polypropylene and polyethylene, various plastics such as nylon, polycarbonate, and (meth)acrylic resins, and various shapes such as metal plates. goods.
The cured film can be made into a film that is excellent in stain resistance and hardness against general household contaminants such as ink and ethanol. It can be excellent in protection.

In addition, the active energy ray-curable polymer composition of the present invention has flexibility, breaking elongation, mechanical strength, and stain resistance that can follow deformation during three-dimensional processing, considering the molecular weight between the calculated network crosslink points. A cured film having both properties and hardness can be obtained.
In addition, the active energy ray-curable polymer composition of the present invention is expected to enable the simple production of a thin resin sheet by single-layer coating.

The breaking elongation of the cured film was measured by cutting the cured film into a width of 10 mm and using a Tensilon tensile tester (Tensilon UTM-III-100, manufactured by Orientec Co., Ltd.) at a temperature of 23 ° C. and a tensile speed of 50 mm / min between chucks. The value measured by performing a tensile test at a distance of 50 mm is preferably 50% or more, more preferably 75% or more, further preferably 100% or more, and 120% or more. is particularly preferred.

The cured films and laminates described above can be used as coating substitute films, and can be effectively applied, for example, to interior and exterior building materials, automobiles, various members of home appliances, and the like.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples unless it exceeds the gist thereof.

[Evaluation method]
The conditions of the polycondensation step and the evaluation methods of the obtained polycarbonate polyols and polyurethanes in the following examples and comparative examples are as follows.

[Polycondensation step]
<Amount of dioxane generated>
The polycarbonate polyol-containing composition and the distillate produced by the polycondensation reaction were analyzed by gas chromatography (GC) and quantified, and the ratio (% by weight) to the charged diethylene glycol was calculated.

[Evaluation of Polycarbonate Polyol]
<Quantification of Carbonate Terminal Amount, Diol, Branched Alcohol Content and Phenol Content>
Polycarbonate polyol is dissolved in CDCl ₃ , 400 MHz ¹ H-NMR (AL-400 manufactured by JEOL Ltd.) is measured, and from the signal position of each component, the amount of carbonate ends such as phenoxy groups, diol, branched alcohol, and phenol are determined. Each content was calculated from the integrated value. The detection limit at that time is 100 ppm as the weight of phenol with respect to the weight of the entire sample, and the compound represented by the above formula (A) and the dihydroxy compound such as the compound represented by the above formula (B) is 0.1% by weight. be. In addition, the ratio of the carbonate terminal amount such as phenoxy group is obtained from the ratio of the integrated value of the carbonate terminal amount such as phenoxy group for one proton and the integrated value for one proton of the entire terminal. The limit of detection is 0.1 mol % for the entire terminus. Similar calculations were made for the ethoxy group (EtO--) when diethyl carbonate was used and the hydroxyethoxy group (HOCH ₂ CH ₂ O--) when ethylene carbonate was used.

<Content ratio of oxyalkylene glycol (A1) (% by weight)>
The content ratio (% by weight) of the oxyalkylene glycol (A1) in the diol (A) is obtained as follows by performing GC analysis after hydrolysis of the polycarbonate polyol.
0.5 g of polycarbonate polyol was precisely weighed, put into a 100 mL Erlenmeyer flask, and dissolved by adding 5 mL of tetrahydrofuran. Next, 45 mL of methanol and 5 mL of 25% by weight sodium hydroxide aqueous solution were added. A condenser was set in a 100 mL Erlenmeyer flask, and the mixture was heated in a water bath at 75 to 80° C. for 30 minutes for hydrolysis. After allowing to cool to room temperature, 5 mL of 6N hydrochloric acid was added to neutralize the sodium hydroxide and adjust the pH to 2-4. The entire amount was transferred to a 100 mL volumetric flask, the inside of the Erlenmeyer flask was washed twice with an appropriate amount of methanol, and the washing liquid was also transferred to the 100 mL volumetric flask. After adding an appropriate amount of methanol to make 100 mL, the liquids were mixed in a volumetric flask. The supernatant was collected, filtered through a filter, and then analyzed by GC. For the concentration of each diol contained in diol (A), a calibration curve was prepared from standard substances, and the weight % was calculated from the area ratio obtained by GC.

<Molar Ratio of Structural Units Derived from Oxyalkylene Glycol (A1) to Structural Units Derived from Branched Alcohol (B)>
Polycarbonate polyol was dissolved in CDCl ₃ , and ¹ H-NMR (AL-400 manufactured by JEOL Ltd.) was measured at 400 MHz. From the signal position of each component, structural units derived from oxyalkylene glycol (A1) and branched alcohol The molar ratio with the structural unit derived from (B) was determined. The molar ratio of the terminal derived from the oxyalkylene glycol (A1) and the terminal derived from the branched alcohol (B) was similarly determined.

<Hydroxyl value>
According to JIS K1557-1, the hydroxyl value of the polycarbonate polyol was measured by a method using an acetylation reagent.

<Measurement of APHA value>
It was measured in accordance with JIS K0071-1 (1998) by comparing polycarbonate polyol with a standard solution in a colorimetric tube. As a reagent, a chromaticity standard solution of 1000 degrees (1 mgPt/mL) (Kishida Chemical Co., Ltd.) was used.

[Evaluation of Polyurethane]
<Solvent resistance>
The polyurethane solution was applied onto a fluororesin sheet (fluorocarbon tape Nitoflon 900, thickness 0.1 mm, manufactured by Nitto Denko Corporation) using a 9.5 mil applicator, and then heated at 50°C for 5 hours, at 100°C for 0.5 hours, It was dried under vacuum conditions at 100° C. for 0.5 hours and at 80° C. for 15 hours in that order. A test piece of 3 cm x 3 cm was cut out from the obtained polyurethane film, placed in a glass petri dish with an inner diameter of 10 cm in which 50 mL of the test solvent was placed, and the weight after immersion in each test solvent at the following temperature for the following time was determined. Measure the weight change rate (%) between the weight of the test piece before immersion and the weight of the test piece after immersion (= (weight of test piece after immersion - weight of test piece before immersion) / test before immersion Weight of piece x 100) was calculated. Here, the closer the weight change rate is to 0%, the better the resistance to oleic acid.
Oleic Acid Resistance: A test piece was immersed in oleic acid at 80° C. for 16 hours.
Ethyl acetate resistance: The specimen was immersed in ethyl acetate for 20 minutes at room temperature.
Ethanol resistance: A test piece was immersed in ethanol at room temperature for 1 hour.

<Room temperature tensile test>
According to JIS K6301, a strip-shaped polyurethane test piece having a width of 10 mm, a length of 100 mm, and a thickness of about 50 μm is chucked using a tensile tester [manufactured by Orientec, product name "Tensilon UTM-III-100"]. A tensile test was performed at a temperature of 23° C. (relative humidity of 55%) at a distance of 50 mm and a tensile speed of 500 mm/min, and the stress at each elongation until the test piece broke was measured. The stress at 100% and 300% elongation is defined as 100% modulus (100% M) and 300% modulus (300% M).

[raw materials used]
Raw materials used in the production of polycarbonate polyol (hereinafter sometimes abbreviated as PCP) and polyurethane are as follows.
Diethylene glycol (hereinafter sometimes abbreviated as DEG): Mitsubishi Chemical Corporation Triethylene glycol (hereinafter sometimes abbreviated as TEG): Mitsubishi Chemical Corporation trimethylolpropane (hereinafter sometimes abbreviated as TMP Yes): 1,6-hexanediol manufactured by Mitsubishi Gas Chemical Co., Ltd. (hereinafter sometimes abbreviated as 16HD): diphenyl carbonate manufactured by BASF (hereinafter sometimes abbreviated as DPC): diethyl manufactured by Mitsubishi Chemical Corporation Carbonate (hereinafter sometimes abbreviated as DEC): Wako Pure Chemical Industries, Ltd. Ethylene carbonate (hereinafter sometimes abbreviated as EC): Mitsubishi Chemical Corporation magnesium acetate tetrahydrate (hereinafter, Mg ( OAc)): Titanium tetrabutoxide manufactured by Wako Pure Chemical Industries, Ltd. (hereinafter sometimes abbreviated as Ti(OBu)): Sodium ethoxide manufactured by Wako Pure Chemical Industries, Ltd. (hereinafter NaOEt ): manufactured by Wako Pure Chemical Industries, Ltd. 1,4-butanediol: manufactured by Mitsubishi Chemical Corporation Diphenylmethane diisocyanate (hereinafter sometimes abbreviated as MDI): urethanization catalyst manufactured by Nippon Polyurethane Industry Co., Ltd. Neostan U-830: manufactured by Nitto Kasei Co., Ltd. Dehydrated N,N-dimethylformamide: manufactured by Wako Pure Chemical Industries, Ltd.

[Production and Evaluation of Polycarbonate Polyol]
<Example I-1>
Diethylene glycol (DEG): 231.8 g, triethylene glycol (TEG): 219.6 g, trimethylolpropane (TMP):7. 5 g, diphenyl carbonate (DPC): 741.2 g, magnesium acetate tetrahydrate aqueous solution: 1.9 mL (concentration: 8.4 g/L) were added, and nitrogen gas was substituted. While stirring, the internal temperature was raised to 160° C. to heat and dissolve the contents. After that, the pressure was lowered to 24 kPa over 2 minutes, and the reaction was allowed to proceed for 90 minutes while removing phenol out of the system. Next, the pressure was lowered to 9.3 kPa over 90 minutes, and further lowered to 0.7 kPa over 30 minutes to continue the reaction, and then the temperature was raised to 170° C. to remove phenol and unreacted dihydroxy compounds out of the system. The reaction was continued for 15 hours (18.5 hours in total). Thereafter, 0.45 mL of a 0.85% aqueous solution of phosphoric acid was added to deactivate the catalyst to obtain a polycarbonate polyol-containing composition. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC.

The obtained polycarbonate polyol-containing composition was fed to a thin film distillation apparatus at a flow rate of 20 g/min, and thin film distillation (temperature: 200°C, pressure: 53 to 67 Pa) was performed. As the thin-film distillation apparatus, a molecular distillation apparatus MS-300 special type manufactured by Shibata Scientific Co., Ltd. with an internal condenser having a diameter of 50 mm, a height of 200 mm and an area of 0.0314 m ² and a jacket was used.
Tables 1A and 1B show the evaluation results of the properties and physical properties of the polycarbonate polyols obtained by thin-film distillation, together with the production conditions.

<Example I-2>
Diethylene glycol (DEG): 786.1 g, triethylene glycol (TEG): 744.7 g, trimethylolpropane (TMP): 25.0 g, triethylene glycol (TEG): 25.0 g, triethylene glycol (TEG): 744.7 g, triethylene glycol (TEG): 25.0 g, triethylene glycol (TEG): 744.7 g. 5 g, diphenyl carbonate (DPC): 2525.0 g, magnesium acetate tetrahydrate aqueous solution: 6.3 mL (concentration: 8.4 g/L) were added, and the mixture was replaced with nitrogen gas. While stirring, the internal temperature was raised to 160° C. to heat and dissolve the contents. After that, the pressure was lowered to 24 kPa over 2 minutes, and the reaction was allowed to proceed for 90 minutes while removing phenol out of the system. Next, the pressure was lowered to 9.3 kPa over 90 minutes, and further lowered to 0.7 kPa over 30 minutes to continue the reaction, and then the temperature was raised to 170° C. to remove phenol and unreacted dihydroxy compounds out of the system. while reacting for 2 hours (5.5 hours in total) to obtain a polycarbonate polyol-containing composition. 0.85% phosphoric acid aqueous solution: 1.4 mL was added to deactivate the catalyst to obtain a polycarbonate polyol-containing composition. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC. After that, the same thin film distillation as in Example 1 was performed.
The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 1A and 1B together with the production conditions.

<Example I-3>
Diethylene glycol (DEG): 1081.3 g, triethylene glycol (TEG): 383.5 g, trimethylolpropane (TMP): 47.0 g, triethylene glycol (TEG): 47.0 g, triethylene glycol (TEG): 383.5 g, triethylene glycol (TEG): 47.0 g, triethylene glycol (TEG): 383.5 g 5 g, diphenyl carbonate (DPC): 2687.8 g, magnesium acetate tetrahydrate aqueous solution: 6.7 mL (concentration: 8.4 g/L) were added, and nitrogen gas was substituted. While stirring, the internal temperature was raised to 160° C. to heat and dissolve the contents. After that, the pressure was lowered to 24 kPa over 2 minutes, and the reaction was allowed to proceed for 90 minutes while removing phenol out of the system. Next, the pressure was lowered to 9.3 kPa over 90 minutes, and further lowered to 0.7 kPa over 30 minutes to continue the reaction, and then the temperature was raised to 170° C. to remove phenol and unreacted dihydroxy compounds out of the system. while reacting for 2 hours (5.5 hours in total) to obtain a polycarbonate polyol-containing composition. 0.85% phosphoric acid aqueous solution: 1.4 mL was added to deactivate the catalyst to obtain a polycarbonate polyol-containing composition. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC. After that, the same thin film distillation as in Example 1 was performed.
The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 1A and 1B together with the production conditions.

<Example I-4>
Diethylene glycol (DEG): 490.2 g, triethylene glycol (TEG): 462.4 g, diphenyl carbonate (DPC): 1547.4 g in a 5 L glass separable flask equipped with a stirrer, distillate trap, and pressure regulator , magnesium acetate tetrahydrate aqueous solution: 4.3 mL (concentration: 8.4 g/L) was added, and the atmosphere was replaced with nitrogen gas. While stirring, the internal temperature was raised to 160° C. to heat and dissolve the contents. After that, the pressure was lowered to 24 kPa over 2 minutes, and the reaction was allowed to proceed for 90 minutes while removing phenol out of the system. Next, the pressure was lowered to 9.3 kPa over 90 minutes, and further lowered to 0.7 kPa over 30 minutes to continue the reaction, and then the temperature was raised to 170° C. to remove phenol and unreacted dihydroxy compounds out of the system. while reacting for 2 hours (5.5 hours in total) to obtain a polycarbonate polyol-containing composition. 0.85% phosphoric acid aqueous solution: 1.1 mL was added to deactivate the catalyst to obtain a polycarbonate polyol-containing composition. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC. After that, the same thin film distillation as in Example 1 was performed.
The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 1A and 1B together with the production conditions.

<Example I-5>
Diethylene glycol (DEG): 166.8 g, trimethylolpropane (TMP): 3.2 g, diphenyl carbonate (DPC): 330.0 g was placed in a 1 L glass separable flask equipped with a stirrer, distillate trap, and pressure regulator. , magnesium acetate tetrahydrate aqueous solution: 0.8 mL (concentration: 8.4 g/L) was added, and nitrogen gas was substituted. While stirring, the internal temperature was raised to 160° C. to heat and dissolve the contents. After that, the pressure was lowered to 24 kPa over 2 minutes, and the reaction was allowed to proceed for 90 minutes while removing phenol out of the system. Next, the pressure was lowered to 9.3 kPa over 90 minutes, and further lowered to 0.7 kPa over 30 minutes to continue the reaction, and then the temperature was raised to 170° C. to remove phenol and unreacted dihydroxy compounds out of the system. After reacting for 2 hours (total 5.5 hours) while stirring, 0.45 mL of 0.85% aqueous solution of phosphoric acid was added to deactivate the catalyst to obtain a polycarbonate polyol-containing composition. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC.
The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 1A and 1B together with the production conditions.

<Example I-6>
Diethylene glycol (DEG): 753.0 g, 1,6-hexanediol (16HD): 462.2 g, trimethylolpropane (TMP) in a 5 L glass separable flask equipped with a stirrer, distillate trap, and pressure regulator. : 22.5 g, diphenyl carbonate (DPC): 2262.3 g, and magnesium acetate tetrahydrate aqueous solution: 5.7 mL (concentration: 8.4 g/L) were introduced and replaced with nitrogen gas. While stirring, the internal temperature was raised to 160° C. to heat and dissolve the contents. After that, the pressure was lowered to 24 kPa over 2 minutes, and the reaction was allowed to proceed for 90 minutes while removing phenol out of the system. Next, the pressure was lowered to 9.3 kPa over 90 minutes, and further lowered to 0.7 kPa over 30 minutes to continue the reaction, and then the temperature was raised to 170° C. to remove phenol and unreacted dihydroxy compounds out of the system. After reacting for 2 hours (total 5.5 hours) while stirring, 1.1 mL of a 0.85% aqueous solution of phosphoric acid was added to deactivate the catalyst to obtain a polycarbonate polyol-containing composition. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC. After that, the same thin film distillation as in Example 1 was performed.
The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 1A and 1B together with the production conditions.

<Comparative Example I-1>
Diethylene glycol (DEG): 231.7 g, triethylene glycol (TEG): 202.5 g, trimethylol were added to a 1 L glass separable flask equipped with a stirrer, a packed rectification column, a distillate trap, and a pressure regulator. Propane (TMP): 6.9 g, diethyl carbonate (DEC): 577.9 g, and titanium tetrabutoxide: 0.23 g were added and replaced with nitrogen gas. While stirring, the internal temperature was raised to 100° C. to heat and dissolve the contents. Thereafter, the mixture was reacted for 20 hours at an internal temperature of 100 to 130° C. under atmospheric pressure while removing ethanol and diethyl carbonate (DEC) from the system. Then, the pressure was lowered to 9.3 kPa over 240 minutes, and the reaction was continued at 160° C. for 10 hours. After further lowering the pressure to 5.0 kPa over 60 minutes and continuing the reaction, the temperature was raised to 170° C. and the reaction was allowed to proceed for 10 hours (45 hours in total) while ethanol and unreacted dihydroxy compounds were removed from the system. A composition was obtained. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC.
The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 2A and 2B together with the production conditions.

<Comparative Example I-2>
Diethylene glycol (DEG): 231.7 g, triethylene glycol (TEG): 202.5 g, trimethylol were added to a 1 L glass separable flask equipped with a stirrer, a packed rectification column, a distillate trap, and a pressure regulator. Propane (TMP): 6.9 g, diethyl carbonate (DEC): 577.9 g, and sodium ethoxide: 0.19 g were added and replaced with nitrogen gas. While stirring, the internal temperature was raised to 100° C. to heat and dissolve the contents. Thereafter, the mixture was reacted for 20 hours at an internal temperature of 100 to 130° C. under atmospheric pressure while removing ethanol and diethyl carbonate (DEC) from the system. Then, the pressure was lowered to 9.3 kPa over 240 minutes, and the reaction was continued at 160° C. for 10 hours. After further lowering the pressure to 5.0 kPa over 60 minutes and continuing the reaction, the temperature was raised to 170° C. and the reaction was allowed to proceed for 10 hours (45 hours in total) while removing ethanol and unreacted dihydroxy compounds from the system. A composition was obtained. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC.
The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 2A and 2B together with the production conditions.

<Comparative Example I-3>
Diethylene glycol (DEG): 231.7 g, triethylene glycol (TEG): 202.5 g, trimethylol were added to a 1 L glass separable flask equipped with a stirrer, a packed rectification column, a distillate trap, and a pressure regulator. Propane (TMP): 6.9 g, ethylene carbonate (EC): 376.9 g, and titanium tetrabutoxide: 1.0 g were added and replaced with nitrogen gas. While stirring, the internal temperature was raised to 160° C. to heat and dissolve the contents. Then, after heating at an internal temperature of 160° C. under atmospheric pressure for 3 hours, the pressure was reduced to 10 kPa, and the reaction was carried out for 20 hours while removing ethylene glycol and ethylene carbonate out of the system. Then, the pressure was lowered to 5.0 kPa over 60 minutes, and the reaction was continued at 160° C. for 10 hours. After further lowering the pressure to 2.0 kPa over 60 minutes and continuing the reaction, the temperature was raised to 170° C. and the reaction was allowed to proceed for 10 hours while removing ethanol and unreacted dihydroxy compound from the system to obtain a polycarbonate polyol-containing composition. (45 hours total). The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC. The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 2A and 2B together with the production conditions.

<Comparative Example I-4>
Diethylene glycol (DEG): 211.4 g, triethylene glycol (TEG): 200.2 g, trimethylolpropane (TMP):6. 8 g, diphenyl carbonate (DPC): 690.6 g, and an aqueous solution of magnesium acetate tetrahydrate: 1.7 mL (concentration: 8.4 g/L) were added and replaced with nitrogen gas. While stirring, the internal temperature was raised to 160° C. to heat and dissolve the contents. After that, the pressure was lowered to 24 kPa over 2 minutes, and the reaction was allowed to proceed for 90 minutes while removing phenol out of the system. Next, the pressure was lowered to 9.3 kPa over 90 minutes, and further lowered to 0.7 kPa over 30 minutes to continue the reaction, and then the temperature was raised to 170° C. to remove phenol and unreacted dihydroxy compounds out of the system. while reacting for 30 minutes (4 hours in total). Thereafter, 0.45 mL of a 0.85% aqueous phosphoric acid solution was added to deactivate the catalyst to obtain a polycarbonate polyol-containing composition. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC. After that, the same thin film distillation as in Example 1 was performed. The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 2A and 2B together with the production conditions.

<Comparative Example I-5>
Diethylene glycol (DEG): 231.8 g, triethylene glycol (TEG): 219.6 g, trimethylolpropane (TMP):7. 5 g, diphenyl carbonate (DPC): 741.2 g, magnesium acetate tetrahydrate aqueous solution: 1.9 mL (concentration: 8.4 g/L) were added, and nitrogen gas was substituted. While stirring, the internal temperature was raised to 130° C. to heat and dissolve the contents. After that, the pressure was lowered to 24 kPa over 2 minutes, and the reaction was allowed to proceed for 90 minutes while removing phenol out of the system. Next, the pressure was lowered to 9.3 kPa over 90 minutes, and further lowered to 0.7 kPa over 30 minutes to continue the reaction, while removing phenol and unreacted dihydroxy compounds from the system while maintaining the temperature at 130°C. The reaction was allowed to proceed for 7 hours (10.5 hours in total). Thereafter, 0.45 mL of a 0.85% aqueous solution of phosphoric acid was added to deactivate the catalyst to obtain a polycarbonate polyol-containing composition. The amount of dioxane contained in the distillate trap, polycarbonate polyol-containing composition was quantified using GC.
The properties and physical properties of the obtained polycarbonate polyol are shown in Tables 2A and 2B together with the production conditions.

[Production and Evaluation of Polyurethane]
<Example II-1, Comparative Example II-4>
Polyurethanes were synthesized by the following method using the polycarbonate polyol produced in Example I-1 (Example II-1) and the polycarbonate polyol produced in Comparative Example I-4 (Comparative Example II-4). , evaluated its physical properties.

A separable flask equipped with a thermocouple and equipped with a stirrer was charged with 81.4 g of polycarbonate polyol preheated to 80° C., 2.8 g of 1,4-butanediol, and 232.2 g of dehydrated N,N-dimethylformamide. and 22.2 mg of the urethanization catalyst (Neostan U-830) were added, and the separable flask was immersed in an oil bath set at 55°C. Stirred for about an hour. After the polycarbonate polyol was dissolved in the solvent, diphenylmethane diisocyanate (MDI) was added little by little over 3 hours, and when a total of 15.0 g of MDI was added, a polyurethane solution was obtained. A test film was prepared from the obtained polyurethane solution by the method described above, and its physical properties were evaluated.
Table 3 shows the results.

As described above, the smaller the weight change rate in the solvent resistance evaluation, the higher the solvent resistance, which is preferable as a polyurethane.
In addition, the smaller the 100% M and 300% M, the higher the flexibility, which is preferable as a polyurethane. In addition, the higher the elongation at break and the strength at break, the higher the mechanical strength, which is preferable for polyurethane.

[Discussion]
In Examples I-1 to I-6, it was possible to obtain a polycarbonate polyol having a dioxane generation amount of 0.1% by weight or less and a low carbonate terminal amount.

In Comparative Examples I-1 to I-3, since a carbonate source other than diphenyl carbonate was used, the reaction rate was low, and although the reaction was carried out for a long time, the amount of carbonate ends was large. A large amount of dioxane was also generated. Moreover, the APHA value was high and the polycarbonate polyol was colored.
In Comparative Example I-4, the amount of carbonate ends was large due to the short reaction time.
Since the reaction temperature was low in Comparative Example I-5, the amount of carbonate ends was large.
From the urethane evaluation results of Example II-1 and Comparative Example II-4, the polyurethane synthesized from the polycarbonate polyol of Example I-1, which has a small amount of carbonate ends, is superior in solvent resistance, elongation at break, and strength at break. Furthermore, it turns out that it is compatible with flexibility.

Claims (10)

A method for producing a polycarbonate polyol, comprising the step of polycondensing a polyhydric alcohol and a carbonate compound,
The polycarbonate polyol has a hydroxyl value of 20 mgKOH/g or more and 450 mgKOH/g or less,
The polyhydric alcohol contains a diol (A),
The diol (A) contains an oxyalkylene glycol (A1) represented by the following formula (1),
The content of the oxyalkylene glycol (A1) in the diol (A) is 60% by weight or more, and the oxyalkylene glycol (A1) contains diethylene glycol,
Terminals derived from the carbonate compound contained in the polycarbonate polyol are 1.0 mol% or less of all terminals,
A method for producing a polycarbonate polyol, wherein the amount of dioxane generated in the polycondensation step is controlled to 1.0% by weight or less with respect to the amount of diethylene glycol added.

(In formula (1), m represents an integer of 2 to 4, and R ^A represents a carbon chain having 2 to 5 carbon atoms and may contain a branch. m R ^A contained in formula (1) may be the same or different). 2. The method for producing a polycarbonate polyol according to claim 1, wherein the carbonate compound is a diaryl carbonate. 3. The method for producing a polycarbonate polyol according to claim 1 or 2, wherein a metal salt of Group 2 of the long-period periodic table is used as a catalyst in the polycondensation step. The method for producing a polycarbonate polyol according to any one of claims 1 to 3, wherein the reaction temperature in the polycondensation step is 150°C or higher and 180°C or lower. 4. The method according to claim 1, further comprising a step of removing unreacted monomers of said polyhydric alcohol after said polycondensation step, and adding a phosphoric acid-based deactivator before said step of removing said unreacted monomers. A method for producing a polycarbonate polyol according to any one of 1 to 4. The polyhydric alcohol further contains a trivalent to hexavalent branched alcohol (B) having 3 to 12 carbon atoms,
The structural unit derived from the branched alcohol (B) in the polycarbonate polyol is 0.005 mol% or more and 5.0 mol% or less with respect to the total number of structural units derived from the polyhydric alcohol in the polycarbonate polyol. The method for producing a polycarbonate polyol according to any one of claims 1 to 5, characterized in that The polycarbonate polyol according to any one of claims 1 to 6, wherein the Hazen color number value (APHA value: according to JIS K0071-1 (1998)) of the polycarbonate polyol is 50 or less. Production method. A method for producing polyurethane using the polycarbonate polyol produced by the method for producing polycarbonate polyol according to any one of claims 1 to 7. A polycarbonate polyol that is a polycondensation reaction product of a polyhydric alcohol and a carbonate compound,
a hydroxyl value of 20 mgKOH/g or more and 450 mgKOH/g or less,
The end derived from the carbonate compound is 1.0 mol% or less in all the ends, and the value of Hazen color number (APHA value: in accordance with JIS K0071-1 (1998)) is 50 or less,
The polyhydric alcohol contains a diol (A) and a trihydric to hexahydric branched alcohol (B) having 3 to 12 carbon atoms,
The diol (A) contains an oxyalkylene glycol (A1) represented by the following formula (1), and the content of the oxyalkylene glycol (A1) in the diol (A) is 60% by weight or more. A polycarbonate polyol, wherein the oxyalkylene glycol (A1) contains diethylene glycol.

(In formula (1), m represents an integer of 2 to 4, and R ^A represents a carbon chain having 2 to 5 carbon atoms and may contain a branch. m R ^A contained in formula (1) may be the same or different). The structural unit derived from the branched alcohol (B) in the polycarbonate polyol is 0.005 mol% or more and 5.0 mol% or less with respect to the total number of structural units derived from the polyhydric alcohol in the polycarbonate polyol. 10. Polycarbonate polyol according to claim 9, characterized in that