JP4899508B2 - Method for producing polyether polyol - Google Patents

Description

  The present invention relates to a method for producing a polyether polyol having a primary terminal hydroxyl group using a double metal cyanide complex catalyst and a polyether polyol obtained by the production method.

Polyether polyols used as raw materials for polyurethane elastomers, adhesives, paints, sealants and the like have been produced so far by polymerizing alkylene oxides such as ethylene oxide and propylene oxide with initiators having active hydrogen atoms. As a typical alkylene oxide polymerization catalyst, a double metal cyanide complex (hereinafter also referred to as a DMC catalyst) is known. The DMC catalyst is a catalyst containing an organic ligand and a metal salt, and is a compound in which an organic ligand, water, and zinc chloride are coordinated to zinc hexacyanocobaltate (Zn ₃ [Co (CN) ₆ ] ₂ ). Is representative.

  Use of tert-butyl alcohol as an organic ligand can significantly extend the life of a DMC catalyst (Patent Document 1), and use of a highly active DMC catalyst using an organic ligand such as tert-butyl alcohol It has also been reported that a polyether polyol can be produced by alkylene oxide polymerization with a small amount of catalyst, and the step of removing the DMC catalyst from the produced polyether polyol can be dispensed with (Patent Document 2).

  By the way, when a polyurethane is produced by a reaction of a polyether polyol and a polyisocyanate, in order to increase the reactivity between the polyether polyol and the polyisocyanate, it is carried out by adding ethylene oxide to the end of the polyether polyol to make it primary. It has been broken. However, for example, in order to make a secondary hydroxyl group at the end of a polyether polyol obtained by polymerizing propylene oxide into a primary hydroxyl group (primary), a small amount of ethylene oxide is converted to a secondary secondary hydroxyl group of the polyether polyol using a DMC catalyst. It was difficult to increase the primary hydroxylation rate of the terminal hydroxyl group without uniform addition of ethylene oxide at the end of the polyether polyol even if it was added to the end of the polyether polyol. A method for producing a terminal primary hydroxyl group-containing polyether polyol by addition polymerization of a mixture of ethylene oxide and propylene oxide to polyoxypropylene triol produced using glycerin as an initiator is known (Patent Documents 3 and 4). However, in the above-mentioned patent document, the polyether polyol produced has a molecular weight as low as about 3000 (hydroxyl value 56 mgKOH / g), and is incompatible with polyoxypropylene polyol, crystalline ethylene oxide homopolymer or terminally crystalline. There was a problem that a polyether polyol having a polyoxyethylene chain added was produced, the polyether polyol became cloudy, the fluidity at normal temperature was lost, or the handling became difficult.

  In addition, as a method for increasing the terminal primary ratio of a relatively high molecular weight polyether polyol produced using a DMC catalyst, the formation of a crystalline ethylene oxide homopolymer is suppressed by copolymerization of propylene oxide and ethylene oxide. (Patent Document 7), however, the amount of DMC catalyst used is large, and it is necessary to remove and purify the catalyst from the produced polyether polyol, or when the proportion of ethylene oxide used during polymerization is increased (80 %), However, there is a problem that the primary ratio of the obtained polyether polyol-terminated hydroxyl group is about 57% and is not high.

  Furthermore, a method (Patent Documents 4 and 8) has been proposed in which the terminal hydroxyl group primary ratio is 40% or more by block copolymerization of propylene oxide and ethylene oxide. Also in this case, since the ratio of ethylene oxide in the alkylene oxide mixture to be used is high (80 wt% or more), a product in which crystalline polyethylene oxide is added to a polyether polyol having a substantially 100% secondary hydroxyl group at the end tends to be formed. .

When producing a polyether polyol having a relatively large molecular weight, even if a small amount of ethylene oxide is to be added to the end, when the ethylene oxide is polymerized using a DMC catalyst, the resulting polyether polyol becomes solid and the fluidity is low. Loss and tend to increase viscosity. Therefore, normally, after producing a polyether polyol such as polyoxypropylene polyol with a DMC catalyst, an addition reaction of ethylene oxide is further performed with an alkali metal catalyst to suppress the formation of crystalline components, and there is no white turbidity or haze. Have produced a terminal-primary polyether polyol having an excellent appearance (Patent Documents 5 and 6). However, even in this case, steps such as neutralization, dehydration, and filtration / separation of the alkali metal catalyst are necessary, and an increase in production cost is a problem.
JP-A-4-145143 JP 2000-513389 Special table 2003-504468 gazette JP-T-2002-543228 Japanese Patent Laid-Open No. 9-3183 JP 2003-301041 A JP-A-3-244632 Special table 2003-503516 gazette

  When a high-molecular weight polyether polyol is produced by copolymerizing an alkylene oxide having 3 or more carbon atoms and ethylene oxide in the presence of a small amount of a highly active double metal cyanide complex that can eliminate the catalyst removal operation, There has been a problem in that a polyoxyethylene block having a high crystallinity and a long chain length that causes the polyether polyol to become cloudy is produced. Therefore, even when alkylene oxide polymerization including ethylene oxide is performed using a highly active double metal cyanide complex catalyst, the content of oxyethylene units and the primary hydroxylation rate of terminal hydroxyl groups are high, and the crystallinity is low. There has been a demand for a method capable of producing a polyether polyol having good properties and easy handling. In general, polyether polyols have a higher molecular weight and a higher ethylene oxide content, resulting in higher viscosity and difficulty in separating the used catalyst. There has been a demand for a method for producing a polyether polyol that can be used. The present invention uses only a small amount of DMC catalyst that can eliminate the catalyst removal operation from the produced polyether polyol, and is cloudy at room temperature even if the primary hydroxyl group primary group conversion rate is relatively high. An object of the present invention is to provide a method for producing a polyether polyol having good fluidity and easy handling.

The present invention has been made to solve the above problems.
That is, the method for producing a polyether polyol of the present invention supplies a mixture of alkylene oxide and ethylene oxide having 3 or more carbon atoms to a polyether polyol initiator in the presence of a double metal cyanide complex catalyst in a reactor. And a method for producing a polyether polyol in which an external block chain is formed on the polyether polyol initiator by performing a random copolymerization reaction under stirring,
As the polyether polyol initiator, a polyether polyol having an average number of functional groups per molecule of 1 to 8, a hydroxyl value of 18 to 200 mgKOH / g, and A% of the terminal hydroxyl groups is a primary hydroxyl group,
The ratio (E mol%) of ethylene oxide in the total mixture of alkylene oxide having 3 or more carbon atoms and ethylene oxide fed into the reactor, and the primary hydroxylation ratio (A%) of the terminal hydroxyl group of the polyether polyol initiator, The ratio of the polyether polyol initiator to the total mass of the polyether polyol obtained by the copolymerization reaction is 3 while maintaining the ratio of ethylene oxide (E mol%) so that the relationship of (EA) <40. The copolymerization reaction is carried out by supplying the mixture of alkylene oxide and ethylene oxide so as to be ˜60 mass%.

In the said manufacturing method, it is preferable to perform copolymerization, stirring the reaction mixture in a reactor using stirring power of 4 kW / m < ³ > or more.

  Furthermore, the copolymerization reaction is preferably performed under a reaction temperature of 120 ° C. or higher.

  In the above production method, the polyether polyol initiator has an oxyethylene block chain obtained by polymerizing ethylene oxide alone in the presence of an alkali metal compound catalyst or a phosphazene compound catalyst, or has a carbon number. It is preferable that a terminal has a random copolymer chain obtained by copolymerizing a mixture of three or more alkylene oxides and ethylene oxide.

Furthermore, this invention relates to the polyether polyol which can be manufactured using the said manufacturing method and has the following characteristics.
(A) The content of oxyethylene units is 40 to 85% by mass,
(B) The primary hydroxylation rate of the terminal hydroxyl group is 40 to 75 mol%,
(C) In terms of polystyrene, the molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) is 1.05-1.30,
(D) the total degree of unsaturation is 0.010 meq / g or less,
(E) the content of all metals derived from the double metal cyanide complex catalyst is 30 ppm or less,
A polyether polyol having a hydroxyl value of less than 18 mgKOH / g.

  In the present invention, the average number of functional groups per molecule of the polyether polyol initiator refers to the average number of active hydrogen atoms per molecule of the active hydrogen atom-containing compound used in producing this initiator. The average number of functional groups per molecule of polyether polyol is the average number of functional groups per molecule of the polyether polyol initiator used in the production method of the present invention.

  The hydroxyl value (mgKOH / g) and the total unsaturation (meq / g) in the present invention are values measured according to JIS-K-1557.

  By using the method for producing a polyether polyol of the present invention, only a small amount of DMC catalyst can be used so that the catalyst removal operation from the produced polyether polyol can be omitted, and by copolymerizing ethylene oxide, oxyethylene units. Even if the primary hydroxylation rate of the terminal hydroxyl group is increased by containing a relatively large amount, no white turbidity occurs at room temperature, the molecular weight distribution is narrow, the total degree of unsaturation is low, the fluidity is good, and the handling is easy. An easy polyether polyol is obtained.

  Below, the manufacturing method of this invention and the polyether polyol manufactured using it are demonstrated in detail.

As described above, the method for producing the polyether polyol of the present invention is a mixture of alkylene oxide and ethylene oxide having 3 or more carbon atoms with respect to the polyether polyol initiator in the presence of the double metal cyanide complex catalyst in the reactor. And a random copolymerization reaction is performed with stirring to form an external block chain in the polyether polyol initiator. Here, the “external block chain” means a molecular chain formed by polymerizing alkylene oxide on the terminal hydroxyl group of the polyether polyol initiator.
Hereinafter, each raw material used for the manufacturing method of this invention and manufacturing conditions are demonstrated.

(Double metal cyanide complex)
The double metal cyanide complex that can be used in the present invention can be produced by a known production method, and can be obtained, for example, by a method described in each of the above patent documents. For example, an organic ligand is coordinated to a reaction product obtained by reacting a metal halide salt and an alkali metal cyanometalate in an aqueous solution, then the solid component is separated, and the resulting solid component is organically separated. A method of further washing with an aqueous ligand solution, or reacting a metal halide salt and an alkali metal cyanometalate in an aqueous organic ligand solution, separating the resulting reaction product (solid component), and obtaining the solid A double metal cyanide complex can be produced by a method of washing the components with an organic ligand aqueous solution.

  A powdery double metal cyanide complex catalyst can be prepared by drying and pulverizing a cake (solid component) obtained by washing and filtering the reaction product obtained by the above method. In addition, an aqueous solution of an organic ligand containing a composite metal cyanide complex catalyst is dispersed in a polyether polyol, and then an excess amount of water and the organic ligand are distilled off to obtain a slurry-like composite metal cyanide. A fluoride complex catalyst can also be prepared.

  As the organic ligand, alcohol, ether, ketone, ester, amine, amide and the like can be used. Particularly preferred organic ligands include tert-butyl alcohol, tert-pentyl alcohol, and ethylene glycol mono-tert- Butyl ether, as well as combinations thereof, for example, tert-butyl alcohol and ethylene glycol mono-tert-butyl ether. By using an organic ligand selected from these, a highly active double metal cyanide complex catalyst can be obtained.

(Polyether polyol initiator)
In the present invention, the polyether polyol initiator has an average functional group number of 1 to 8 per molecule, a hydroxyl value of 18 to 200 mgKOH / g, preferably 18 to 112 mgKOH / g, more preferably 18 to 40 mgKOH / g. The polyether polyol which is g is used. The average functional group number of the polyether polyol initiator is the largest factor that determines the number of functional groups of the polyether polyol finally produced according to the production method of the present invention.

  In the above production method, the polyether polyol initiator has an oxyethylene block chain obtained by polymerizing ethylene oxide alone in the presence of an alkali metal compound catalyst or a phosphazene compound catalyst, or has a carbon number. It is preferable that a terminal has a random copolymer chain obtained by copolymerizing a mixture of three or more alkylene oxides and ethylene oxide.

  The polyether polyol initiator can be produced by polymerizing alkylene oxide to an arbitrarily selected initiator having a molecular weight lower than that of the polyether polyol initiator. Examples of initiators for this include monools such as methanol, ethanol, propanol, butanol, and hexanol, water, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, trimethylolpropane, glycerin, pentaerythritol, sorbitol, And polyols such as sucrose are preferably used.

  Examples of the alkylene oxide having 3 or more carbon atoms include propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, epichlorohydrin, styrene oxide, cyclohexene oxide, and oxetane. Two or more of these can be used in combination. Propylene oxide is particularly preferred.

  As a catalyst used for manufacture of the said polyether polyol initiator, an alkali catalyst is preferable and NaOH, KOH, CsOH, etc. are especially preferable. The alkali metal compound catalyst and the phosphazene compound catalyst need to use a larger amount of the catalyst for the alkylene oxide polymerization as compared with the DMC catalyst, and further, a catalyst removal step is required after the alkylene oxide polymerization. However, these catalysts are well known as catalysts capable of relatively uniformly adding ethylene oxide to the end of the polyether polyol. When producing a polyether polyol initiator having a high content of oxyethylene units, This is advantageous as a catalyst that hardly forms a crystalline polyoxyethylene chain that causes white turbidity.

  The primary hydroxylation of the polyether polyol initiator is performed by random copolymerization of a mixture of an alkylene oxide having 3 or more carbon atoms and an ethylene oxide directly or after polymerizing an alkylene oxide having 3 or more carbon atoms to an appropriate initiator. Can be done. At this time, the primary ratio can be controlled by changing the ratio of the ethylene oxide monomer to the alkylene oxide having 3 or more carbon atoms. That is, in general, the higher the proportion of ethylene oxide, the higher the proportion of primary hydroxyl ends of the resulting polyether polyol initiator.

  A polyether polyol initiator can also be obtained by polymerizing an alkylene oxide having 3 or more carbon atoms with a suitable initiator and then further block-polymerizing ethylene oxide alone at the end of the obtained polyether polyol (this is called capping). Can be primary hydroxylated. When the primary hydroxyl group conversion rate of the polyether polyol initiator having a block polymer chain at the terminal is controlled by polymerizing ethylene oxide alone, the addition amount of ethylene oxide is usually the mass of the polyether polyol initiator. It is preferable to set it as 3-30 mass% (20-95% in a primary conversion rate) with respect to 5-20 mass% (30-90% in a primary conversion rate). Increasing this ratio increases the crystallinity of the polyether polyol initiator.

  The ratio of terminal hydroxyl groups in the polyether polyol initiator is expressed in A%. A is preferably a numerical value exceeding 0 and not exceeding 100%. In particular, it is preferably 5 to 95%, more preferably 10 to 90%.

  In addition, the polyether polyol initiator has an ester bond formed by ring-opening polymerization of a cyclic ester such as a tetramethyleneoxy chain or caprolactone formed by ring-opening polymerization of tetrahydrofuran within the range in which the transparency of the polyether polyol initiator is not lost. , And a carbonate bond formed by copolymerizing alkylene carbonate may be included as part of the molecular structure.

(Formation of external block for polyether polyol initiator by copolymerization of alkylene oxide having 3 or more carbon atoms and ethylene oxide: production of polyether polyol of the present invention)
The method for producing the polyether polyol of the present invention comprises a mixture of an alkylene oxide and an ethylene oxide having 3 or more carbon atoms with respect to the polyether polyol initiator in the presence of the above-mentioned double metal cyanide complex catalyst in a reactor. And a random copolymerization reaction is performed with stirring to form a polyether polyol initiator with an external block chain.

  In the prior art, when a block chain containing oxyalkylene units is formed by polymerizing an alkylene oxide containing ethylene oxide at the end of a polyether polyol initiator using a double metal cyanide complex catalyst, the resulting polyether polyol becomes cloudy. And the problem that the primary hydroxylation rate of the terminal hydroxyl group does not increase. This is because the polymerization activity of the double metal cyanide complex catalyst is high and the reactivity of ethylene oxide is high, so that the addition reaction of ethylene oxide concentrates on a specific terminal hydroxyl group, particularly a primary hydroxyl group, of the initiator. This is probably because an ethylene block is formed. This phenomenon is more remarkable when substantially 100% of the terminal hydroxyl groups of the polyether polyol initiator are secondary hydroxyl groups, or as the proportion of ethylene oxide in the alkylene oxide used for polymerization increases.

  The present inventors studied a method of preventing ethylene oxide from concentrating at a specific initiator terminal and homopolymerizing, and allowing ethylene oxide to react uniformly with each initiator terminal as much as possible. As a result, the ratio of primary hydroxyl groups (A%) of the terminal hydroxyl group of the polyether polyol initiator and the proportion of ethylene oxide in the total mixture of alkylene oxide and ethylene oxide having 3 or more carbon atoms to be reacted with this initiator (E mol%) By keeping the difference between E and A not exceeding 40, in other words, when it is desired to increase the proportion of ethylene oxide, the primary hydroxylation rate of the terminal hydroxyl group so that (EA) is less than 40 It was found that by using a polyether polyol initiator having a high viscosity, ethylene oxide can be prevented from being concentrated and polymerized at the end of a specific initiator, and a polyether polyol having excellent transparency and fluidity can be produced. It has been completed.

  Qualitatively speaking, the meaning of the parameters set as described above increases the proportion of ethylene oxide in the mixture of alkylene oxides by increasing the primary hydroxylation rate of the terminal hydroxyl groups of the polyether polyol initiator. In other words, the occurrence of non-uniform polymerization does not cause the molecular weight distribution of the obtained polyether polyol to be widened, fluidity is not impaired, and significant cloudiness does not occur.

  That is, in the method for producing a polyether polyol of the present invention, the proportion (E mol%) of ethylene oxide in the total mixture of alkylene oxide and ethylene oxide having 3 or more carbon atoms to be fed into the reactor for carrying out the polymerization reaction, and the polyether The relationship between the terminal hydroxyl group primary ratio (A%) of the polyol initiator is (EA) <40, more preferably −50 <(EA) <30, particularly preferably −50 <(E− A) The ratio of ethylene oxide (E mol%) is maintained so that <20, and the alkylene oxide polymerization reaction is performed.

  The value of E can take any value in the range of greater than 0 and less than 100, but in the present invention, E is preferably 41 to 90 mol%, more preferably 50 to 85 mol%, and 60 to 80 Mole% is particularly preferred. The value of E is close to the value of the primary ratio of the terminal hydroxyl group of the finally obtained polyether polyol. In the present invention, the larger the value of E, the more remarkable the effect of the present invention. That is, the higher the primary ratio of the terminal hydroxyl group of the polyether polyol to be finally obtained, the more remarkable the effect of the present invention.

  The primary hydroxylation rate of the terminal hydroxyl group of the polyether polyol obtained by conducting a polymerization reaction on the polyether polyol initiator using a mixture of propylene oxide and ethylene oxide having E of 41 to 90 mol% is determined by the production method of the present invention. When used, it is usually about 40-75%. In addition, the terminal hydroxyl group primary ratio of the polyether polyol obtained by performing a polymerization reaction on a polyether polyol initiator using a mixture of propylene oxide and ethylene oxide having E of 60 to 80 mol% is usually about 60 to 70. %. Thus, the primary hydroxylation rate of the terminal hydroxyl group of the polyether polyol obtained by polymerizing an alkylene oxide mixture containing ethylene oxide with a polyether polyol initiator generally has a specific value corresponding to the value of E. Therefore, setting (EA) to less than the above specific value means that the terminal hydroxyl group primary ratio of the polyether polyol initiator and the terminal hydroxyl group primary ratio of the finally obtained polyether polyol are determined. This also means that the difference is reduced to a value less than a specific value (which does not necessarily match the specific value of E). In this way, by preventing the ethylene oxide from concentrating on a specific initiator terminal and polymerizing, a polyether polyol having a narrow molecular weight distribution, no white turbidity, good fluidity and easy handling is produced. Is possible.

  The particularly preferred values of E and A can also vary depending on the molecular weight of the polyether polyol initiator to be produced. For example, the higher the molecular weight of the polyether polyol initiator, the easier it is to add ethylene oxide to the initiator non-uniformly. Therefore, as the molecular weight of the polyether polyol initiator increases, that is, as the hydroxyl value of the initiator decreases, the proportion (E mol%) of ethylene oxide in the alkylene oxide mixture used for polymerization and the terminal hydroxyl group of the polyether polyol initiator. It is preferable to set so that the difference (EA) in the primary rate (A%) becomes small.

  In the present invention, a polyether polyol in which a mixture of an alkylene oxide having 3 or more carbon atoms having a specific monomer composition and ethylene oxide is supplied to a polyether polyol initiator to form an external block chain in the polyether polyol initiator. It is a manufacturing method. In the present invention, a multistage block copolymerization method in which the composition of a mixture of an alkylene oxide having 3 or more carbon atoms and ethylene oxide is changed stepwise can also be employed. In this case, in each stage of the multistage block copolymerization, the ratio (E mol%) of ethylene oxide in the mixture of alkylene oxide having 3 or more carbon atoms and ethylene oxide used for the polymerization, and the polyether polyol produced up to that stage The difference (EA) from the primary hydroxylation ratio (A%) of the terminal hydroxyl group is (EA) <40, more preferably −50 <(EA) <30, particularly preferably −50 <. The alkylene oxide polymerization reaction is carried out while maintaining the ratio of ethylene oxide (E mol%) so that (EA) <20.

  The hydroxyl value of the polyether polyol produced by the production method of the present invention is not particularly limited, but the production method of the present invention is particularly suitable for the production of a high molecular weight polyether polyol having an ethylene oxide copolymer chain. The hydroxyl value is particularly preferably less than 18 mgKOH / g. The lower limit of the hydroxyl value is not particularly limited, but is preferably 2 mgKOH / g or more, particularly preferably 5 mgKOH / g or more. Moreover, the primary hydroxylation rate of the terminal hydroxyl group of the polyether polyol obtained by the production method of the present invention is usually 40 to 75 mol%, and this is mainly determined according to the value of E as described above.

  When the polyether polyol is produced by the production method of the present invention, the proportion of the polyether polyol initiator in the total mass of the product polyether polyol is preferably 3 to 60% by mass, and 10 to 35%. More preferably it is. Therefore, a mixture of an alkylene oxide having 3 or more carbon atoms and an ethylene oxide in an amount corresponding to the remaining portion of the ratio of the polyether polyol initiator to the total mass of the polyether polyol obtained by the copolymerization reaction is supplied and co-polymerized. Perform a polymerization reaction.

  Further, the hydroxyl value of the polyether polyol to be produced is determined according to the amount of alkylene oxide having 3 or more carbon atoms and ethylene oxide to be addition-polymerized to the polyether polyol initiator. This is a technical matter well known to those skilled in the art.

  The polyether polyol initiator and the DMC catalyst are generally charged into the reactor before the polymerization reaction is started, but after the polymerization reaction is started, an additional polyether polyol initiator and / or DMC catalyst is added. You may supply in a reactor individually or with the mixture of C3 or more alkylene oxide and ethylene oxide. Here, “reactor” refers to all types of reactors used for the polymerization of alkylene oxide, such as batch reactors and continuous reactors.

Furthermore, in the production method of the present invention, it is preferable to use reaction conditions that can reduce the concentration of alkylene oxide and ethylene oxide having 3 or more carbon atoms in the reaction system, that is, in the reaction mixture, and make it as uniform as possible. When producing a high molecular weight polyether polyol, it is difficult to make the monomer concentration in the reaction system uniform because the viscosity of the reaction mixture is high, so it is particularly important to maintain the stirring condition of the reaction mixture at an appropriate condition. It is important in the manufacturing method of the invention. It is preferable to sufficiently stir the reaction mixture and move the reaction mixture up and down, left and right. For that purpose, it is preferable to use a large stirring blade having a shape suitable for stirring and mixing a high viscosity liquid. As stirring conditions, when the viscosity at 25 ° C. of the reaction mixture in the reactor is, for example, 3000 cp or more, further 4000 cp or more, particularly 5000 cp or more, the reaction mixture in the reactor is 4 kW / m ³ or more, preferably 6 kW / m It is preferable to stir using a stirring power of m ³ or more, more preferably 8 kW / m ³ or more.

  Here, the “stirring power” is a value calculated as a known power required for stirring, and this value is the volume and viscosity of the contents in the reactor, the shape of the reactor, and the shape of the stirring blade. And the required power per unit liquid amount of the contents calculated from the number of revolutions and the like. The preferable stirring power in the production method of the present invention refers to a value for the reaction mixture in the reactor at the end of the polymerization reaction. Therefore, it is not always necessary that the stirring power satisfy the above range from the start to the end of the polymerization reaction.

  Preferable examples of the stirring blade used in the present invention include the stirring blade described in JP-A-2003-342361. The stirring blade is particularly preferably a large blade, and examples thereof include large blades such as Full Zone (registered trademark) blade manufactured by Shinko Pantech Co., Ltd. and Max Blend (registered trademark) blade manufactured by Sumitomo Heavy Industries, Ltd. In addition, paddle blades, pitched paddle blades, turbine blades, propeller blades, and the like can also be used. In this case, the stirring blade diameter is 20 to 95%, preferably 30% to 90%, particularly preferably relative to the inner diameter of the reactor. It is in the range of 40 to 80%.

In the production method of the present invention, it is preferable to further use the following polymerization reaction conditions.
(1) The polymerization temperature is preferably 120 ° C. or higher, more preferably 130 ° C. or higher. By increasing the reaction temperature, the viscosity of the reaction mixture can be lowered to increase the stirring efficiency. The polymerization temperature is preferably 150 ° C. or lower in order not to lower the catalyst activity.
(2) The monomer feed rate into the reactor is made as low as possible to reduce the difference in the monomer concentration due to the difference in position in the reactor. In particular, in the stage where the addition reaction of the monomer to the polyether polyol initiator proceeds and the monomer is added to the polyether polyol having a hydroxyl value of less than 18 mgKOH / g, the monomer partial pressure of the gas phase in the reactor is The monomer supply rate is selected so that it is preferably 0.18 MPa or less, more preferably 0.12 MPa or less, and particularly preferably 0.08 MPa or less.
(3) By increasing the number of monomer supply nozzles arranged in the reactor, the monomer supply into the reaction system is dispersed as much as possible, and the monomer concentration at a specific position in the reactor is more conspicuous than the concentration at other positions. To prevent it from becoming high.

(Use amount of DMC catalyst)
The amount of the DMC catalyst used in the present invention is such that the DMC catalyst-derived metal (for example, Zn and Co) content remaining in the finally produced polyether polyol is 30 ppm or less, preferably 15 ppm or less, particularly preferably 10 ppm. The amount is preferably as follows. By reducing the metal derived from the DMC catalyst remaining in the polyether polyol, a purification process for removing the catalyst from the polyether polyol can be omitted. Conventionally, when trying to produce a polyether polyol with a small amount of DMC catalyst, a large molecular weight and a high content of oxyethylene units, normally, ethylene oxide is not uniformly added to the end of the polyether polyol molecule. It was difficult to produce a polyether polyol that did not occur. The catalyst may be initially charged into the reactor together with the polyether polyol initiator, or may be sequentially divided and added during the course of the polymerization reaction.

  In the present invention, the primary hydroxylation rate of the terminal hydroxyl group of the polyether polyol initiator, the proportion of ethylene oxide in the mixture of alkylene oxide and ethylene oxide having 3 or more carbon atoms used for block copolymerization, polymerization temperature, stirring conditions, etc. By selecting, it is possible to produce a polyether polyol which has a high molecular weight and does not become cloudy even if the content of oxyethylene units is high even if the amount of DMC catalyst used is reduced.

  Although an example of the outline of the procedure in the case of actually manufacturing polyether polyol using the manufacturing method of this invention is as follows, embodiment of this invention is not limited to this. Usually, in the molecular design of the polyether polyol, the primary hydroxylation rate of the terminal hydroxyl group, the ratio of the oxyethylene unit in the polyether polyol, the average number of functional groups per molecule, the average molecular weight, and the like are determined. When propylene oxide is used as the alkylene oxide having 3 or more carbon atoms and a mixture of this and ethylene oxide is copolymerized at the end of the polyether polyol initiator, the polyether polyol terminal hydroxyl group is obtained depending on the proportion of propylene oxide and ethylene oxide used. The value of the primary rate is almost determined. Therefore, when the value of the primary ratio of the terminal hydroxyl group of the target polyether polyol is determined, the proportion of ethylene oxide (E mol%) in the monomer is determined accordingly. Next, based on the value of E, the primary ratio A% of the polyether polyol initiator terminal hydroxyl group to be used is determined so that (EA) <40. Thereafter, the molecular weight and average number of functional groups of the initiator, the amount of monomer added to the initiator, and the like are determined so that the desired polyether polyol can be obtained, and the polymerization reaction is performed using the above-described preferable reaction conditions. Those skilled in the art can easily determine these parameters as appropriate.

(Alkylene oxide having 3 or more carbon atoms)
Examples of the alkylene oxide having 3 or more carbon atoms used in the present invention include propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, epichlorohydrin, styrene oxide, cyclohexene oxide, and oxetane. Two or more of these may be used in combination. Propylene oxide is particularly preferred. A monomer other than alkylene oxide selected from cyclic carbonates and cyclic esters may be copolymerized with an alkylene oxide having 3 or more carbon atoms. When a monomer other than alkylene oxide is used, the amount used is preferably 10% by mass or less of the entire monomer including alkylene oxide.

(Polyether polyol)
Furthermore, the following (c) to (e) are achieved by using an appropriate amount of a highly active DMC catalyst in the production method of the present invention, and the content of oxyethylene units in the polyether polyol obtained in the production method of the present invention In accordance with the chemical structure and amount of the polyether polyol initiator, the amount of the monomer to be polymerized to the polyether polyol initiator, and the proportion of ethylene oxide in the whole monomer. In addition to (c) to (e), the following (a) and (a) can be easily set by using the production conditions of the present invention. A polyether polyol having the characteristics of (b) and not easily clouded and having a hydroxyl value of less than 18 mgKOH / g is obtained.
(A) The content of oxyethylene units is 40 to 85% by mass,
(B) The primary hydroxylation rate of the terminal hydroxyl group is 40 to 75 mol%,
(C) In terms of polystyrene, the molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) is 1.05-1.30,
(D) the total degree of unsaturation is 0.010 meq / g or less,
(E) The content of all metals derived from the double metal cyanide complex catalyst is 30 ppm or less.

Furthermore, the above (a) to (e)
(A ′) the content of oxyethylene units is 55 to 80% by mass,
(B ′) the primary hydroxyl group conversion rate is 50 to 70 mol%,
(C ′) in terms of polystyrene, the molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) is 1.10 to 1.30,
(D ′) the total unsaturation is 0.008 meq / g or less,
(E ′) the content of all metals derived from the double metal cyanide complex catalyst is 15 ppm or less,
It is preferable.

  By producing using the production method of the present invention, a polyether polyol having fluidity is obtained even when stored at room temperature (20 to 25 ° C.) for 1 month or longer without becoming cloudy.

  The polyether polyol having the characteristics (a) to (e) above is an example of a preferred embodiment of the polyether polyol produced using the production method of the present invention, and the production method of the present invention is the above (a) to (a) The method is not limited to the method for producing the polyether polyol having the feature (e).

(Use of polyether polyol)
The polyether polyol obtained by the production method of the present invention is suitable for the production of polyurethane foam and polyurethane elastomer. In general, when a polyurethane bond is formed from a polyether polyol and a polyisocyanate compound in the production of a polyurethane resin, the larger the primary ratio of the terminal hydroxyl group of the polyether polyol, the faster the polyurethane bond forming reaction. The production method of the present invention is excellent as a method for obtaining a polyether polyol having a high reaction rate with a polyisocyanate compound. Further, by controlling the amount of oxyethylene units contained in the polyether polyol using the method for producing the polyether polyol of the present invention, the hydrophilicity and hydrophobicity of the polyether polyol and the solubility in water can be improved. A polyether polyol can be produced that is controllable and has desirable properties as a base polyol for surfactants, hydraulic oils, and lubricating oils.

  For example, in recent years, in order to avoid unmanned equipment and the risk of fire, hydraulic oil used in hydraulic equipment has been replaced by water-glycol flame retardant hydraulic oil instead of flammable mineral oil. It is becoming. Water-glycol flame retardant hydraulic oil is generally composed of 40% water, 40% glycol, and 20% polyether polyol. Among these, water is glycol for the purpose of imparting flame retardancy to hydraulic oil. Is used to prevent the hydraulic oil from freezing and solidifying at low temperatures. Therefore, the polyether polyol blended in the flame retardant hydraulic oil needs to be mixed well with water, and a polyether polyol having a high content of oxyethylene units is used. Polyether polyols give hydraulic oils viscosity and lubricity that are insufficient with water and glycols alone. Further, the hydraulic oil needs to have a small viscosity change due to temperature, that is, a large viscosity index, but the viscosity index increases as the molecular weight of the polyether polyol increases. It is preferred to use a large polyether polyol. In addition, the higher the molecular weight of the polyether polyol used in the hydraulic oil, the smaller the coefficient of friction due to the oil film formed on the metal surface and the better the lubricity. Therefore, polyether polyols containing oxyethylene units produced by the method of the present invention in the molecular chain are particularly useful for water-glycol flame retardant hydraulic fluids.

〔Example〕
Hereinafter, the present invention will be specifically described based on Examples and Comparative Examples, but the present invention is not limited thereto. Reference Example 1 is a production example of a double metal cyanide complex catalyst, and Reference Examples 2 to 6 are production examples of a polyether initiator. The manufacture example of the polyether polyol of this invention was shown as Comparative Examples 1-5 as Examples 1-10.

The weight average molecular weight Mw, number average molecular weight Mn, and molecular weight distribution Mw / Mn of the polyethers obtained in the following examples were measured by GPC (gel permeation chromatography) method at room temperature and using a tetrahydrofuran solvent as an eluent. The value measured using a calibration curve obtained using a standard polystyrene sample with a known molecular weight.
The total unsaturation degree (meq / g) of the polyether polyol was measured according to JIS-K-1557.

The primary ratio of the polyether polyol initiator and the terminal hydroxyl group of the polyether polyol was measured by H-NMR method. That is, after adding trifluoroacetic acid to a CDCl ₃ solution of a polyether to esterify a terminal hydroxyl group, (i) a methine hydrogen atom (terminal 2) formed by addition of beta-cleavage of propylene oxide at the molecular end. Multiple peaks (5.20-5.30 ppm; based on tetramethylsilane (0 ppm), the same shall apply hereinafter) based on the hydrogen atom bonded to the carbon atom to which the secondary hydroxyl group is bonded), (ii) propylene oxide is alpha-cleavaged at the molecular end Two types of double line peaks (5.25 ppm and 4.30 ppm) of methylene hydrogen atoms (hydrogen atoms bonded to carbon atoms bonded with terminal primary hydroxyl groups) formed by addition of (iii) molecular ends A methylene hydrogen atom formed by adding ethylene oxide to a hydrogen atom bonded to a carbon atom bonded with a terminal primary hydroxyl group. By measuring the intensity ratio of the triplet peak (4.48-4.50 ppm), the percentage of primary hydroxyl groups of the polyether polyol initiator and the polyether polyol is determined. At this time, the hydrogen atom of the methylidene group CH ₂ of the terminal allyl group (CH ₂ ═CH—CH ₂ —) measured from the H-NMR spectrum before adding trifluoroacetic acid to the polyether polyol initiator or polyether polyol ( A correction is made to subtract the intensity of 5.15-5.30 ppm (quadruplex peak) from the intensity of 5.20-5.30 ppm after addition of trifluoroacetic acid.

(Reference Example 1) “Production of DMC catalyst”
An aqueous solution consisting of 10.2 g of zinc chloride and 10 g of water was placed in a 500 mL flask. An aqueous solution consisting of 4.2 g of potassium hexacyanocobaltate (K ₃ Co (CN) ₆ ) and 75 g of water was added dropwise to the aqueous zinc chloride solution in the flask over 30 minutes while stirring at 300 rpm (number of revolutions / minute). added. During this time, the mixed solution in the flask was kept at 40 ° C. After the dropwise addition of the aqueous potassium hexacyanocobaltate solution, the mixture in the flask was further stirred for 30 minutes, and then 80 g of tert-butyl alcohol (hereinafter abbreviated as TBA), 80 g of water, and 0.6 g of polyol P (using KOH). Then, a mixture consisting of 168 mg KOH / g polyether triol obtained by adding propylene oxide to glycerin) was added and stirred at 40 ° C. for 30 minutes and further at 60 ° C. for 60 minutes. The obtained mixture was filtered under pressure (0.25 MPa) using a circular filter plate having a diameter of 125 mm and a quantitative filter paper for fine particles (No. 5C manufactured by ADVANTEC), and the composite metal cyanide complex was contained. A solid (cake) was isolated.

  Subsequently, the cake containing the obtained double metal cyanide complex was transferred to a flask, a mixture of 36 g of TBA and 84 g of water was added and stirred for 30 minutes, and then pressure filtration was performed under the same conditions as above to obtain a cake. The obtained cake was transferred to a flask, a mixture of 108 g of TBA and 12 g of water was further added and stirred for 30 minutes, and a double metal cyanide complex catalyst (hereinafter also referred to as DMC catalyst) was dispersed in the TBA-water mixed solvent. A liquid (slurry) was obtained. After 120 g of the above polyol P was added to and mixed with this slurry, volatile components were distilled off under reduced pressure at 80 ° C. for 3 hours and further at 115 ° C. for 3 hours to obtain a slurry-like DMC catalyst. The concentration of the solid catalyst component in the slurry was 3.9% by mass.

  The preparation of the polyether polyol initiator is shown in (Reference Example 2) to (Reference Example 7). Table 1 shows the EO content (% by mass), the hydroxyl value (mgKOH / g), and the primary rate (%) of the obtained polyether initiator.

Reference Example 2 “Preparation 1 of Polyether Polyol Initiator 1”
In a 10 L reactor equipped with a paddle blade stirring device, 191 g of glycerin and 24 g of KOH were added, the inside of the reactor was purged with nitrogen, the internal temperature was raised to 120 ° C., and vacuum dehydration was performed for 4 hours. Thereafter, a mixture of ethylene oxide (EO) and propylene oxide (PO) (mass ratio EO / PO = 80/20) was continuously supplied to the 7809 g reactor in total to perform ring-opening polymerization at 100 ° C.

  After the supply of the mixture of EO and PO was completed, the mixture was further heated and stirred at 100 ° C. for 120 minutes to react unreacted PO as much as possible, and then degassing was performed for 120 minutes while maintaining the internal temperature at 100 ° C.

  To the obtained polyether polyol, a powder of sodium acid pyrophosphate was added as a neutralizing agent. The amount of sodium acid pyrophosphate added is 1.5 equivalents with respect to KOH contained in the polyether polyol, and the mixture is stirred at 90 ° C. for 1 hour and 120 ° C. for 1 hour to neutralize the polyether polyol. Went. After the neutralization reaction, an amount of synthetic magnesium silicate (trade name: KW600, manufactured by Kyowa Chemical Industry Co., Ltd.) in an amount corresponding to 0.5% by mass of the polyether polyol was added and stirred at 120 ° C. for 1 hour. The vacuum degassing was performed at 120 ° C. for 120 minutes. A neutralizer and an adsorbent, which are solid components, were separated from the polyether polyol using a filter, and a purified transparent polyether polyol initiator was obtained.

Reference Example 3 “Preparation 2 of Polyether Polyol Initiator”
In a 10 L reactor equipped with a paddle blade stirring device, 276 g of propylene glycol and 24 g of KOH were added, the inside of the reactor was purged with nitrogen, the internal temperature was raised to 120 ° C., and vacuum dehydration was performed for 4 hours. . Thereafter, a total of 7724 g of a mixture of EO and PO (mass ratio EO / PO = 80/20) was continuously supplied to the reactor, and ring-opening polymerization was performed at 100 ° C. After completion of the reaction, vacuum degassing was performed for 120 minutes. The obtained transparent polyether polyol initiator was purified in the same manner as in Reference Example 2.

Reference Example 4 “Preparation 3 of Polyether Polyol Initiator”
In a 10 L reactor equipped with a paddle blade stirring device, 191 g of glycerin and 24 g of KOH were added, the inside of the reactor was purged with nitrogen, the internal temperature was raised to 120 ° C., and vacuum dehydration was performed for 4 hours. Thereafter, 5770 g of PO was supplied and reacted at 100 ° C. Further, 890 g of EO was supplied and reacted at 100 ° C. After the reaction, vacuum degassing was performed for 120 minutes. The obtained transparent polyether polyol initiator was purified in the same manner as in Reference Example 2.

Reference Example 5 “Preparation 4 of Polyether Polyol Initiator”
In a 10 L reactor equipped with a paddle blade stirring device, 191 g of glycerin and 24 g of KOH were added, the inside of the reactor was purged with nitrogen, the internal temperature was raised to 120 ° C., and vacuum dehydration was performed for 4 hours. Thereafter, 6450 g of PO was supplied and reacted at 100 ° C. After the reaction, vacuum degassing was performed for 120 minutes. The obtained transparent polyether polyol initiator was purified in the same manner as in Reference Example 2.

Reference Example 6 “Preparation 5 of Polyether Polyol Initiator”
In a 10 L reactor equipped with a paddle blade stirring device, 276 g of propylene glycol and 24 g of KOH were added, the inside of the reactor was purged with nitrogen, the internal temperature was raised to 120 ° C., and vacuum dehydration was performed for 4 hours. . Thereafter, a total of 7780 g of PO was continuously supplied to the reactor to perform ring-opening polymerization at 100 ° C. After completion of the polymerization, vacuum degassing was performed for 120 minutes. The obtained transparent polyether polyol initiator was purified in the same manner as in Reference Example 2.

Reference Example 7 “Preparation 6 of Polyether Polyol Initiator”
In a 10 L reactor equipped with a paddle blade stirring device, 276 g of propylene glycol and 24 g of KOH were added, the inside of the reactor was purged with nitrogen, the internal temperature was raised to 120 ° C., and vacuum dehydration was performed for 4 hours. . Thereafter, a total of 7722 g of a mixture of EO and PO (mass ratio EO / PO = 50/50) was continuously supplied to the reactor to perform ring-opening polymerization at 100 ° C. After completion of the reaction, vacuum degassing was performed for 120 minutes. The obtained transparent polyether polyol initiator was purified in the same manner as in Reference Example 2.

  The production of polyether polyol is shown in [Example 1] to [Example 10]. Table 2 shows the physical property values of the obtained polyether polyol.

[Example 1] "Production of polyether polyol 1"
In a 10 L reactor equipped with a paddle blade (stirring blade diameter is 50% of the inner diameter of the reactor), 2546 g of the initiator of Reference Example 2 and 10.3 g of a slurry DMC catalyst (0.4 g of solid catalyst) Including ingredients.). After replacing the inside of the reactor with nitrogen, the internal temperature was raised to 130 ° C., and 255 g of an EO / PO mixture (the ratio E of EO in the mixture was 71.0 mol%) was added. Copolymerization began with catalyst activation. Once the pressure inside the reactor has dropped, EO / PO is fed into the 2600 g reactor at a rate of 20 g / min, and then 10 g so that the gas phase monomer partial pressure does not exceed 0.08 MPa. 2600 g of EO / PO was supplied at a rate of 1 min / min or less. While supplying EO / PO into the reactor, the polymerization reaction was carried out by stirring at a rotational speed of 220 rpm (stirring power = 12 kW / m ³ ) while maintaining the internal temperature of the reactor at about 130 ° C. . After the completion of the reaction, the mixture was further heated and stirred at 130 ° C. for 60 minutes to react unreacted EO / PO as much as possible.
EO content (mass%), hydroxyl value (mgKOH / g), primary ratio (%), total unsaturation degree (meq / g), polystyrene-reduced weight average molecular weight (Mw) of the obtained polyether polyol Table 2 shows the ratio of / number average molecular weight (Mn), the ratio (mass%) of the initiator to the polyol, the viscosity (cp) at 25 ° C., and the metal residue (Zo, Co) (ppm). Table 2 also shows the state after 1 month storage at 25 ° C. The proportion (mol%) of ethylene oxide (EO) in the mixture of alkylene oxide (PO) having 3 or more carbon atoms and ethylene oxide (EO) in this example and the primary ratio of initiator polyether polyol (%) The difference was 71.0-45.6 = 25.4.

[Example 2]
In the catalyst activation at the beginning of the polymerization reaction, 255 g of a mixture of EO / PO mixture (the ratio of EO in the mixture is 77.8 mol%) and 5200 g in the subsequent polymerization reaction at a rate of 10 g / min. A high molecular weight EO / PO copolymer polyether polyol was produced in the same manner as in Example 1 except that it was supplied. The results are shown in Table 2. The difference between the proportion (mol%) of ethylene oxide in the monomer and the primary conversion ratio (%) of the polyether polyol initiator in this example was 77.8-45.6 = 32.2.

Example 3
In the same 10 L reactor as in Example 1, 1697 g of the polyether polyol initiator produced in Reference Example 2 and 10.3 g of a slurry DMC catalyst (containing 0.4 g of a solid catalyst component) were charged. After replacing the inside of the reactor with nitrogen, the internal temperature was raised to 130 ° C., and 170 g of an EO / PO mixture (the ratio of EO in the mixture was 78.3 mol%) was added. Copolymerization starts with catalyst activation, and once the pressure inside the reactor has dropped, 2500 g of EO / PO mixture is supplied at a rate of 10 g / min, and then the monomer partial pressure in the gas phase is 0.08 MPa. While maintaining the temperature not exceeding, a further 3633 g of EO / PO mixture was fed at a rate of 10 g / min or less to carry out the polymerization reaction. Thereafter, a polyether polyol was produced in the same manner as in Example 1. The results are shown in Table 2. The difference between the proportion (mol%) of ethylene oxide in the monomer and the primary ratio (%) of the polyether polyol initiator in this example was 78.3-45.6 = 32.7.

Example 4
In the same 10 L reactor as in Example 1, 1157 g of the polyether polyol initiator produced in Reference Example 2 and 10.3 g of a slurry DMC catalyst (containing 0.4 g of a solid catalyst component) were charged. After replacing the inside of the reactor with nitrogen, the internal temperature was raised to 130 ° C., and 116 g of an EO / PO mixture (the ratio of EO in the mixture was 78.9 mol%) was added. Copolymerization started with catalyst activation, and 2000 g of EO / PO mixture was supplied at a rate of 10 g / min after the pressure in the reactor once increased, and the monomer partial pressure in the gas phase exceeded 0.08 MPa. An additional 4727 g of EO / PO mixture was fed at a rate of 10 g / min or less. Thereafter, a polyether polyol was produced in the same manner as in Example 1. The results are shown in Table 2. The difference between the proportion (mol%) of ethylene oxide in the EO / PO mixture in this example and the primary conversion ratio (%) of the polyether polyol initiator was 78.9-45.6 = 33.3.

Example 5
In the same 10 L reactor as in Example 1, 1455 g of the polyether polyol initiator produced in Reference Example 3 and 10.3 g of a slurry DMC catalyst (containing 0.4 g of a solid catalyst component) were charged. After replacing the inside of the reactor with nitrogen, the internal temperature was raised to 130 ° C., and 146 g of an EO / PO mixture (the ratio of EO in the mixture was 73.8 mol%) was added. Copolymerization starts with catalyst activation, and 2500 g of EO / PO mixture is supplied at a rate of 10 g / min after the pressure inside the reactor once lowered, and the monomer partial pressure in the gas phase exceeds 0.08 MPa. 3899 g of EO / PO mixture was fed at a rate of not more than 10 g / min. Thereafter, a polyether polyol was produced in the same manner as in Example 1. The results are shown in Table 2. The difference between the proportion (mol%) of ethylene oxide in the EO / PO mixture in this example and the primary conversion ratio (%) of the polyether polyol initiator was 73.8-52.6 = 21.2.

Example 6
A polyether polyol was produced in the same manner as in Example 5 except that the ratio of EO in the EO / PO mixture fed into the reactor was 78.9%. The results are shown in Table 2. The difference between the ratio (mol%) of ethylene oxide in the EO / PO mixture in this example and the primary conversion ratio (%) of the polyether polyol initiator was 78.9-52.6 = 26.3.

Example 7
In the same 10 L reactor as in Example 1, 970 g of the polyether polyol initiator produced in Reference Example 3 and 10.3 g of DMC catalyst slurry (containing 0.4 g of solid catalyst component) were charged. After replacing the inside of the reactor with nitrogen, the internal temperature was raised to 130 ° C., and 97 g of an EO / PO mixture (the ratio of EO in the mixture was 74.3 mol%) was added. Copolymerization starts with catalyst activation, and once the pressure inside the reactor has dropped, 3000 g of EO / PO mixture is fed into the reactor at a rate of 10 g / min, and the gas phase monomer partial pressure is 0 In order not to exceed 0.08 MPa, 3933 g of an EO / PO mixture was fed into the reactor at a rate of 10 g / min or less. Thereafter, a polyether polyol was produced in the same manner as in Example 1. The results are shown in Table 2. The difference between the ratio (mol%) of ethylene oxide in the EO / PO mixture in this example and the primary conversion ratio (%) of the polyether polyol initiator was 74.3-52.6 = 21.7.

Example 8
A polyether polyol was produced in the same manner as in Example 7 except that the monomer fed into the reactor was an EO / PO mixture (the ratio of EO in the mixture was 78.9 mol%). The results are shown in Table 2. The difference between the ratio (mol%) of ethylene oxide in the EO / PO mixture in this example and the primary conversion ratio (%) of the polyether polyol initiator was 78.9-52.6 = 26.3.

Example 9
2000 g of the polyether polyol initiator prepared in Reference Example 4 was used as an initiator, and an EO / PO mixture in the initial catalyst activation stage of the polymerization reaction (the ratio of EO in the mixture was 78.3 mol%) 200 g, then 3500 g of EO / PO mixture at a rate of 10 g / min is constantly fed into the reactor, and further the rate of 10 g / min or less so that the monomer partial pressure in the gas phase does not exceed 0.08 MPa. A polyether polyol was produced in the same manner as in Example 1 except that 1640 g of the EO / PO mixture was fed into the reactor. The results are shown in Table 2. The difference between the ratio (mol%) of ethylene oxide in the EO / PO mixture in this example and the primary conversion ratio (%) of the polyether polyol initiator was 78.3-81.3 = -3.

Example 10
1500 g of the polyether polyol initiator prepared in Reference Example 4 was used as an initiator, and an EO / PO mixture in the initial catalyst activation stage of the polymerization reaction (the ratio of EO in the mixture was 78.3 mol%) 150 g of EO / PO mixture at a rate of 10 g / min is continuously fed into the reactor, and the monomer partial pressure in the gas phase is not more than 0.08 MPa, and is not more than 10 g / min. A polyether polyol was produced in the same manner as in Example 1 except that 3350 g of the EO / PO mixture was fed into the reactor at a rate. The results are shown in Table 2. The difference between the ratio (mol%) of ethylene oxide in the EO / PO mixture in this example and the primary conversion ratio (%) of the polyether polyol initiator was 78.3-81.3 = -3.

  Comparative examples for the present invention are shown below as [Comparative Example 1] to [Comparative Example 6]. The results are shown in Table 3.

[Comparative Example 1]
A polyether polyol was produced in the same manner as in Example 1 except that the polyether polyol initiator produced in Reference Example 5 was used instead of the polyether polyol initiator used in Example 1. The results are shown in Table 3. The difference between the proportion (mol%) of ethylene oxide in the EO / PO mixture used in Comparative Example 1 and the primary conversion ratio (%) of the polyether polyol initiator was 71.0−0.4 = 70.6. there were.

[Comparative Example 2]
A polyether polyol was produced in the same manner as in Example 5 except that the polyether polyol initiator produced in Reference Example 6 was used instead of the polyether polyol initiator used in Example 5. The results are shown in Table 3. The difference between the ratio (mol%) of ethylene oxide in the EO / PO mixture used in Comparative Example 2 and the primary conversion ratio (%) of the polyether polyol initiator is 73.8−0.3 = 73.5. there were.

[Comparative Example 3]
A polyether polyol was produced in the same manner as in Example 8 except that the polyether polyol initiator produced in Reference Example 7 was used. The difference between the ratio (mol%) of ethylene oxide in the EO / PO mixture used in Comparative Example 3 and the primary conversion ratio (%) of the polyether polyol initiator is 78.9-14.5 = 64.4. there were. The molecular weight distribution of the polyether polyol obtained in Comparative Example 3 was wider than that of the polyether polyol obtained in Example 8, and white turbidity was observed at room temperature.

Claims (5)

In the reactor, a mixture of alkylene oxide and ethylene oxide having 3 or more carbon atoms is supplied to the polyether polyol initiator in the presence of a double metal cyanide complex catalyst, and a random copolymerization reaction is performed with stirring to perform the random copolymerization reaction. A method for producing a polyether polyol in which an outer block chain is formed on a polyether polyol initiator,
As the polyether polyol initiator, a polyether polyol having an average number of functional groups per molecule of 1 to 8, a hydroxyl value of 18 to 200 mgKOH / g, and A% of the terminal hydroxyl groups is a primary hydroxyl group,
The ratio (E mol%) of ethylene oxide in the total mixture of alkylene oxide having 3 or more carbon atoms and ethylene oxide fed into the reactor, and the primary hydroxylation ratio (A%) of the terminal hydroxyl group of the polyether polyol initiator, The ratio of the polyether polyol initiator to the total mass of the polyether polyol obtained by the copolymerization reaction is 3 while maintaining the ratio of ethylene oxide (E mol%) so that the relationship of (EA) <40. A method for producing a polyether polyol, comprising carrying out a copolymerization reaction by supplying the alkylene oxide and ethylene oxide mixture so as to be ˜60 mass%. The method for producing a polyether polyol according to claim 1, wherein the copolymerization reaction is performed while stirring the reaction mixture in the reactor using a stirring power of 4 kW / m ³ or more.   The method for producing a polyether polyol according to claim 1 or 2, wherein the copolymerization reaction is performed under a reaction temperature of 120 ° C or higher.   The polyether polyol initiator has an oxyethylene block chain obtained by polymerizing ethylene oxide alone in the presence of an alkali metal compound catalyst or a phosphazene compound catalyst, or an alkylene oxide and ethylene oxide having 3 or more carbon atoms. The manufacturing method of the polyether polyol as described in any one of Claims 1-3 which has a random copolymer chain obtained by copolymerizing this mixture at the terminal. Manufactured by the method according to any one of claims 1 to 4,
(A) The content of oxyethylene units is 40 to 85% by mass,
(B) The primary hydroxylation rate of the terminal hydroxyl group is 40 to 75 mol%,
(C) In terms of polystyrene, the molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) is 1.05-1.30,
(D) the total degree of unsaturation is 0.010 meq / g or less,
(E) the content of all metals derived from the double metal cyanide complex catalyst is 30 ppm or less,
A polyether polyol having a hydroxyl value of less than 18 mgKOH / g.