JP2011225734A - Method of producing polyether polycarbonate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing polyether polycarbonate, by which a by-product having a hydroxy group can be selectively removed with a simple operation and high purity polyether polycarbonate can be obtained with high yield.SOLUTION: The method of producing polyether polycarbonate includes the following steps 1 and 2. Step 1: a step of polycondensing a carbonic ester and a polyether diol by transesterification. Step 2: a step of subjecting a product obtained at the step 1 to a contact treatment with an activated carbon having an average pore diameter of 1.0 nm or less and a wetting index of 65 mN/m or less.

Description

  The present invention relates to a method for producing a polyether polycarbonate.

  It is known that specific polyether polycarbonates can be used as a main component to adhere adhesives to each other, but become adhesives having "selective adhesiveness" that has low adhesiveness to fingers and articles. (For example, see Patent Document 1).

  As a method for producing such a polycarbonate, a method in which a carbonic ester and a diol are transesterified and polycondensed is widely used (for example, see Patent Document 2). In addition, it is known that an organic compound having a hydroxyl group is generated as a by-product in the reaction (see, for example, Patent Document 3).

  Various methods have been proposed as a method for removing a compound having a hydroxyl group, but a removal method utilizing the adsorption characteristics of activated carbon is widely used industrially (see, for example, Patent Documents 4 and 5).

JP 2009-41004 A JP 2007-155421 A JP 2008-239650 A JP-A-3-207485 Japanese Patent Publication No. 61-51957

  When a polyether polycarbonate is produced by transesterification and polycondensation of a carbonate ester and a polyether diol, a compound having a hydroxyl group derived from the starting carbonate is contained as a reaction byproduct in the obtained reaction end product. . The reaction by-product having such a hydroxyl group gives off an irritating odor due to its low molecular weight, and there is a concern that the adhesive performance may be deteriorated due to a decrease in product purity of the polyether polycarbonate by the reaction by-product having a hydroxyl group. Therefore, it is necessary to provide a purification step for removing reaction byproducts after the polycondensation reaction by transesterification.

  To solve this problem, the technique described in Patent Document 3 uses an impurity removal method by distillation. However, when the polyether polycarbonate and impurities are separated by distillation, the separation operation becomes complicated because the melt viscosity of the polyether polycarbonate is very high. Further, a method of removing impurities using an adsorbent such as activated carbon as described in Patent Documents 4 and 5 after dissolving the polyether polycarbonate in a solvent or the like to lower the apparent viscosity is also conceivable. Since not only reaction by-products but also polyether polycarbonate is adsorbed, obtaining a high-purity polyether polycarbonate is accompanied by a significant decrease in yield.

  Accordingly, an object of the present invention is to produce a polyether polycarbonate capable of selectively removing a by-product having a hydroxyl group by a simple operation and obtaining a high-purity polyether polycarbonate in a high yield. It is to provide a method.

The present invention provides a method for producing a polyether polycarbonate comprising the following steps 1 and 2.
Step 1: Transesterification of carbonate ester and polyether diol and polycondensation Step 2: The product obtained in Step 1 has an average pore diameter of 1.0 nm or less and a wetting index of 65 mN / m or less. Process of contact with activated carbon

  According to the present invention, by-products having a hydroxyl group can be selectively removed by a simple operation, and a high-purity polyether polycarbonate can be obtained with a high yield.

[Polyether polycarbonate]
In the present invention, the polyether polycarbonate is preferably a polyether polycarbonate having a structural unit represented by the following general formula (I).

[式中、Ａは炭素数２〜６のアルキレン基、ｎは平均値で５〜１０００の数、ｐは平均値で５〜１００の数であり、（ｎ×ｐ）個のＡは同一でも異なっていても良い。]

[In the formula, A is an alkylene group having 2 to 6 carbon atoms, n is an average value of 5 to 1000, p is an average value of 5 to 100, and (n × p) A are the same. It may be different. ]

  In the general formula (I), A represents an alkylene group having 2 to 6 carbon atoms, and (n × p) A may be the same or different, but an alkylene group having 2 to 4 carbon atoms is preferable, and carbon An alkylene group having 2 or 3 is more preferred, and a mixture of an ethylene group and a propylene group is more preferred.

  Moreover, when it consists of different alkyleneoxy groups, these may have a block structure or a random structure, but a random structure is more preferable.

In general formula (I), n shows the average addition mole number of an alkyleneoxy group, is a number of 5-1000, Preferably it is a number of 7-700, More preferably, it is a number of 10-500. p represents an average repeating number of _[(AO) n COO] structural units, the number of 5 to 100, preferably 7 to 70, more preferably a number from 10 to 50.

  From the viewpoint of reducing stickiness, the weight average molecular weight of the polyether polycarbonate is preferably 80,000 or more, more preferably 100,000 or more, and further preferably 150,000 or more. Depending on the application, when used as an adhesive having “selective tackiness”, it is preferably 1,000,000 or less, more preferably 500,000 or less, and even more preferably 300,000 or less from the viewpoint of exhibiting sufficient tackiness at room temperature. .

  The weight average molecular weight of the polyether polycarbonate is a value measured by the method described in Examples.

[Method for producing polyether polycarbonate]
The method for producing a polyether polycarbonate of the present invention includes the following step 1 and step 2.

<Step 1>
Step 1 is a step of subjecting carbonate ester and polyether diol to polycondensation by transesterification.

  The carbonic acid ester used in Step 1 is preferably a carbonic acid ester of an alcohol having 1 to 12 carbon atoms, and is not particularly limited, but specifically, dimethyl carbonate, diphenyl carbonate, diethyl carbonate, ethylene carbonate, carbonic acid Examples thereof include propylene and the like, and dimethyl carbonate and diphenyl carbonate are preferable.

  As the polyether diol used in Step 1, a compound represented by the following general formula (II) is suitable.

HO- (AO) _n -H (II)
[Wherein, A is an alkylene group having 2 to 6 carbon atoms, n is an average value of 5 to 1000, and n A may be the same or different. ]

  In the general formula (II), A represents an alkylene group having 2 to 6 carbon atoms, and n A's may be the same or different, but an alkylene group having 2 to 4 carbon atoms is preferable, and 2 or 3 carbon atoms. Are more preferable, and those in which an ethylene group and a propylene group are mixed are more preferable.

  Moreover, when it consists of different alkyleneoxy groups, these may have a block structure or a random structure, but a random structure is more preferable.

  In general formula (II), n shows the average addition mole number of an alkyleneoxy group, is a number of 5-1000, Preferably it is 7-700, More preferably, it is a number of 10-500.

  Specific examples of the polyether diol represented by the general formula (II) include, but are not limited to, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and a copolymer of ethylene oxide and propylene oxide. A copolymer of ethylene oxide and propylene oxide is preferred, and a random copolymer of ethylene oxide and propylene oxide is more preferred. Commercially available products may be used as the polyether diol, and examples thereof include ADEKA polyether PR-3005, 3007, PR-5007 (manufactured by ADEKA Corporation) and the like.

  From the viewpoint of obtaining good solubility in water or alcohol, the number average molecular weight of the polyether diol used in the present invention is preferably 200 to 50000, more preferably 300 to 30000, and still more preferably 400 to 20000.

  In step 1 of the present invention, other polyols may coexist in addition to the polyether diol. Other polyols include diols such as ethylene glycol, propylene glycol, butanediol, tetramethylene glycol, 2,2-dimethyl-1,3-propanediol, pentanediol and hexanediol, polyols such as glycerin, sorbitol, and pentaerythritol. And aromatic-containing diols such as bisphenol A and ethylene oxide adducts of bisphenol A.

  The ratio of the polyether diol to the total polyol is preferably 50% by weight or more, more preferably 80% by weight or more, and still more preferably 90% by weight or more.

  From the viewpoint of selective tackiness, the reaction molar ratio between the carbonate ester and the polyether diol when transesterifying the carbonate ester and the polyether diol is expressed as 1 / mol of the carbonate ester / mol of the polyether diol. 0.9 to 1 / 1.1 is preferable, and 1 / 0.95 to 1 / 1.05 is more preferable.

  When transesterifying the carbonate ester and the polyether diol, a normal ester exchange reaction catalyst can be used. Examples of such catalysts include alkali metals, alkaline earth metals, and alkoxides, hydrides, hydroxides, carbonates, acetates, oxides, zinc, aluminum, tin, titanium, lead, germanium, and the like. , Antimony, bismuth, nickel, iron, manganese, zirconium and the like. Moreover, organic base compounds, such as a triethylamine and imidazole, can also be used. Among these catalysts, compounds of alkali metals such as sodium, potassium, rubidium and cesium, and compounds such as tin and titanium are preferable.

  The type of reaction may be any of batch type, continuous type, and a combination of batch type and continuous type, and the apparatus used may be any of tank type, tube type, tower type, vertical type, horizontal type. .

  The reaction temperature in the ester exchange / polycondensation reaction between the carbonate ester and the polyether diol is preferably 80 to 300 ° C. from the viewpoint of suppressing thermal decomposition of the reaction product and obtaining a good-quality polyether polycarbonate, and is preferably 100 to 250. ° C is more preferable, 110-200 ° C is still more preferable, and 120-180 ° C is especially preferable.

  The reaction pressure may be normal pressure, but is preferably under reduced pressure. In the case of reduced pressure, volatilization of the elimination alcohol is promoted, the elimination alcohol can be effectively removed out of the system, and the polycondensation reaction of the polyether polycarbonate can be efficiently advanced. As pressure reduction conditions, 0.1-67 kPa (absolute pressure) is preferable, and 0.5-40 kPa (absolute pressure) is more preferable.

  In the case of normal pressure, removal of the desorbed alcohol out of the system can be promoted by circulating an inert gas such as nitrogen. Furthermore, the combined use of reduced pressure and inert gas flow can more effectively remove the desorbed alcohol from the system.

  After completion of the transesterification / polycondensation reaction between the carbonate ester and the polyether diol, an alcohol having 1 to 4 carbon atoms is added to the obtained polyether polycarbonate, and it is uniformly diluted and dissolved. Can be extracted. The temperature at which alcohol is added to dilute and dissolve the polyether polycarbonate is preferably 15 to 120 ° C, more preferably 50 to 120 ° C, and still more preferably 60 to 100 ° C. The pressure for the dilution / dissolution operation may be normal pressure or increased pressure.

  The addition amount of the alcohol having 1 to 4 carbon atoms is preferably 0.01 to 20 parts by weight, more preferably 0.5 to 15 parts by weight, and still more preferably 1 to 10 parts by weight with respect to 1 part by weight of the polyether polycarbonate. .

<Process 2>
Step 2 is a step of contacting the product obtained in Step 1 with activated carbon having an average pore size of 1.0 nm or less and a wetting index of 65 mN / m or less.

  In Step 2, the by-product having a hydroxyl group generated during the reaction in Step 1 can be selectively removed. Here, as a by-product having a hydroxyl group, it is contained as an impurity in the carbonate ester or polyether diol used as a reaction raw material, including alcohol released from the carbonate ester during the ester exchange between the carbonate ester and the polyether diol. Low molecular weight hydroxyl groups formed by reacting these low molecular weight hydroxyl group compounds with each other or with a carbonate, polyether diol, or elimination alcohol during the reaction in Step 1. In particular, when an aromatic alcohol carbonate is used as a carbonate ester raw material in order to allow the reaction to proceed satisfactorily, the viewpoint of preventing the generation of irritating odors and off-flavors and the viewpoint of increasing product purity To aromatic compounds having by-produced hydroxyl groups, especially diphenyl carbonate It is desired to remove the phenol by-produced when the Le as a raw material.

  The activated carbon used in step 2 is carbon activated by carbonizing raw materials such as coconut shells, coal, and wood at a high temperature, and then performing activation treatment (that is, special treatment for generating pores in the carbide).

  Examples of activated carbon activation treatment methods include gas activation methods using activation gases other than halogen gas (for example, active gases such as water vapor, oxygen, and carbon dioxide), and chemical activation methods using chemicals such as phosphoric acid and zinc chloride. Although known, the activation method of the activated carbon used in the present invention is not particularly limited.

  Various forms of activated carbon such as powder, granules, granules, fibers, columns, and spheres are known, but the form of activated carbon used in the present invention is not particularly limited.

  The activated carbon used in the present invention has an average pore diameter of 1.0 nm or less, preferably 0.1 to 0.8 nm, more preferably 0, from the viewpoint of developing sufficient adsorption ability for by-products having a hydroxyl group. Those having an average pore diameter of 2 to 0.5 nm, more preferably 0.3 to 0.45 nm are suitable.

  The activated carbon used in the present invention has an average pore diameter in the above specific range and a wetness index of 65 mN / in, from the viewpoint of selectively adsorbing a by-product having a hydroxyl group and obtaining a polyether polycarbonate in a high yield. It is important that it is not more than m, and those showing a wetting index of preferably 20 to 65 mN / m, more preferably 20 to 63 mN / m are suitable. Here, the “wetting index” is a surface hydrophilicity / hydrophobicity parameter, and the larger the value, the higher the surface hydrophilicity, and the smaller the value, the higher the surface hydrophobicity. The “wetting index” of activated carbon is a value measured by the method described in the examples.

  In the present invention, the yield of the polyether polycarbonate is reduced by contact-treating the product (polyether polycarbonate solution) obtained in step 1 with activated carbon having an average pore diameter and a wetting index in the specific ranges described above. And by-products having a hydroxyl group can be selectively removed. Here, from the viewpoint of obtaining a high-purity polyether polycarbonate that does not exhibit an irritating odor or strange odor, the content of by-products having a hydroxyl group is preferably 20 mg / kg or less, more preferably 15 mg / kg, based on the polyether polycarbonate. In the following, it is more preferable to lower it to 10 mg / kg or less.

  The method for contacting the product (polyether polycarbonate solution) obtained in Step 1 with activated carbon is not particularly limited, and for example, a known method such as a batch method or a continuous method can be used. Specifically, 1) a batch method in which activated carbon is directly put into a polyether polycarbonate solution charged in an activated carbon treatment tank, and 2) the polyether polycarbonate solution is distributed to a fixed bed type adsorption tower packed with activated carbon. Examples thereof include a continuous method in which the liquid is passed in a circulating manner or a circulating manner.

  When the batch method is used, the shape of the activated carbon is not particularly limited, but is preferably a powder.

  In the batch method, the concentration of the polyether polycarbonate solution to be contacted with activated carbon is not particularly limited, but is preferably 3 to 50% by weight, and more preferably 5 to 30% by weight. Moreover, 10-500 weight% is preferable with respect to polyether polycarbonate, 20-400 weight% is more preferable, and, as for the addition amount of activated carbon, 30-300 weight% is still more preferable.

  In the batch method, the contact treatment temperature between the activated carbon and the polyether polycarbonate solution is not particularly limited, but is preferably in the range of 0 to 70 ° C, more preferably in the range of 5 to 40 ° C. The contact time is preferably 0.5 to 50 hours, more preferably 1 to 36 hours, and further preferably 3 to 24 hours.

  When the contact treatment is performed using a batch method, the activated carbon is separated from the polyether polycarbonate solution after the contact treatment. As a method for separating activated carbon, a known solid-liquid separation method such as filtration separation or centrifugation can be used. In the present invention, filtration separation is preferably used. In the filtration separation, a known filter aid can be used from the viewpoint of increasing the filtration efficiency.

  When the contact treatment is performed by a continuous method using a fixed bed adsorption tower, the shape of the activated carbon is not particularly limited, but is preferably granular.

  In the continuous method, the concentration of the polyether polycarbonate solution to be contacted with activated carbon is not particularly limited, but is preferably 3 to 50% by weight, and more preferably 5 to 30% by weight. Moreover, 10-500 weight% is preferable with respect to the polyether polycarbonate to contact-treat, and the usage-amount of activated carbon has more preferable 20-400 weight%, and 30-300 weight% is still more preferable.

When the contact treatment is performed by a continuous method, it is desirable to perform a pretreatment in order to remove the fine powder contained in the activated carbon. Examples of the pretreatment method include a method of passing a pretreatment liquid from the bottom of an adsorption tower filled with activated carbon. Examples of the pretreatment liquid include water, an organic solvent, a mixture of water and an organic solvent, and the like. It is preferable to use a solvent constituting the polyether polycarbonate solution. The superficial velocity of the pretreatment liquid is preferably 5 to 50 m / hr from the viewpoint of sufficiently removing fine powder and preventing leakage of activated carbon from the upper part of the adsorption tower and use of an excessive amount of pretreatment liquid. / Hr is more preferable. Here, the superficial velocity is obtained by dividing the flow rate [m ³ / hr] of the pretreatment liquid by the adsorption tower cross-sectional area [m ² ].

When the contact treatment is carried out by a continuous method using a fixed bed adsorption tower, the space velocity of the polyether polycarbonate solution is not particularly limited, but it is preferable from the viewpoint of sufficiently removing the by-product having a hydroxyl group and improving the productivity. It is 0.1-3 hr < ^-1 >, More preferably, it is 0.3-1.5 hr < ^-1 >. Here, the space velocity is obtained by dividing the flow rate [m ³ / hr] of the polyether polycarbonate solution by the activated carbon filling volume [m ³ ].

  The superficial velocity of the polyether polycarbonate solution is not particularly limited, but is preferably 5 m / hr or less from the viewpoint of reducing pressure loss and reducing equipment loads such as a liquid feed pump.

  In the continuous method, the contact treatment temperature between the activated carbon and the polyether polycarbonate solution is not particularly limited, but a range of 0 to 70 ° C is preferable, and a range of 5 to 40 ° C is more preferable.

  In both the batch method and the continuous method, the stabilizer can be added to the polyether polycarbonate solution after the polyether polycarbonate solution is contact-treated with activated carbon. A well-known thing can be used as a stabilizer, For example, a dibutylhydroxytoluene (BHT) is mentioned. The concentration of the stabilizer to be added is not particularly limited, but is preferably 10 to 1000 mg / kg with respect to the polyether polycarbonate.

  When using the polyether polycarbonate obtained by the manufacturing method of this invention for an adhesive, it is preferable to contain a solvent. Examples of the solvent include water and alcohols having 1 to 4 carbon atoms. The content of the solvent in the pressure-sensitive adhesive is preferably 99.9% by weight or less, and more preferably 99% by weight or less. Such an adhesive is applied to or transferred to one or both surfaces of a plastic film such as a polyester film, a porous material such as paper, nonwoven fabric or woven fabric, or a metal foil or the like, and is in the form of a sheet or tape. It can be used as a pressure-sensitive adhesive sheet, and is particularly useful as a selective pressure-sensitive adhesive having low adhesiveness, although the pressure-sensitive adhesives stick to each other.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited at all by this Example.

  In the following examples, the weight average molecular weight of the polyether polycarbonate, the residual phenol concentration, the polyether polycarbonate concentration of the polyether polycarbonate solution, the average pore diameter of the activated carbon, and the wetting index of the activated carbon were measured by the following methods.

<Measurement method of weight average molecular weight>
It measured on the following conditions by the gel filtration chromatography (GPC) using a polystyrene gel. The molecular weight was calibrated with a polystyrene standard sample, and the weight average molecular weight was determined.

GPC measurement conditions and sample concentration: 0.25 wt% (chloroform solution)
・ Sample injection volume: 100μL
・ Eluent: Chloroform ・ Flow rate: 1.0 mL / min
・ Measurement temperature: 40 ℃
・ Column: Product name `` KG '' (1) + Product name `` K-804L '' (2) (above, Shodex)
・ Detector: Differential refractometer (GPC device, trade name “HLC-8220GPC” (Tosoh Corporation) attached)
Polystyrene standard samples: `` TSKstandard POLYSTYRENE F-10 '' (molecular weight 102,000), F-1 (1020,000), A-1000 (870) (above, Tosoh Corporation) and `` POLYSTYRENE STANDARD '' (molecular weight 900,000, 30,000) ; Nishio Industry Co., Ltd.)

<Measurement method of residual phenol concentration>
The residual phenol concentration was measured by gas chromatography (GC) under the following conditions, and was determined by the absolute calibration method. The phenol concentration was calculated as the concentration relative to the polyether polycarbonate.

GC measurement conditions and equipment: Product name “6890N Network GC system” (Agilent Technologies)
Column: Trade name “DB-1” (Agilent Technologies; 100% dimethylpolysiloxane; model number Agilent 122-1031; length 30 m, diameter 0.25 mm, film thickness 0.1 μm)
・ Conditions: Split mode (split ratio 1:25), inlet temperature 250 ° C, detector temperature 300 ° C, column temperature 50 ° C, hold for 4 minutes, heat up to 300 ° C at 10 ° C / min · Detector: FID ( GC device Product name `` 6890N Network GC system '' (Agilent Technologies Inc.)

<Measurement method of polyether polycarbonate concentration of polyether polycarbonate solution>
The polyether polycarbonate concentration of the polyether polycarbonate solution was measured with an infrared moisture meter under the following conditions.

Infrared moisture meter measurement conditions and equipment: Product name "FD-240" (Kett Science Laboratory Co., Ltd.)
・ Measurement value standard: Solid content ・ Measurement condition: Drying temperature; 105 ℃, Measurement mode; Automatic measurement mode (monitoring time 60 seconds)

<Measurement method of average pore diameter of activated carbon>
The average pore diameter of the activated carbon was measured under the following conditions using a specific surface area / pore distribution measuring device.

Measurement condition equipment for specific surface area / pore distribution measuring device: Product name “ASAP2020” (manufactured by Shimadzu Corporation)
Measurement temperature: Liquid nitrogen temperature (approximately 77K)
Surface area measurement method: Multipoint average pore diameter measurement method: BJH method activated carbon Pretreatment temperature: 250 ° C (5 hours)

<Method for measuring wetness index of activated carbon>
The wetness index of the activated carbon was measured by the following procedure.

  Surface tension 73mN / m, 70mN / m, 65mN / m, 60mN / m, 56mN / m, 50mN / m, 45mN / m, 40mN / m, 35mN / m, 30mN / m 1 mL of a standard solution defined in K 6768 was placed in a separate glass container (volume 2 mL). Next, 0.1 mg of powdered (powder particle size range: 10 to 100 μm) activated carbon is sequentially added from a container containing a standard solution having a high surface tension (ie, 73 mN / m → 70 mN / m → 65 mN / m → ·). (... → 30 mN / m in order), sprinkled on the liquid surface. The surface tension of the liquid mixture for wet tension test when activated carbon first settled from the liquid surface was defined as the wetting index of the activated carbon sample. The test was conducted at 25 ° C., and the presence or absence of sedimentation was judged in a state one minute after the activated carbon was sprinkled on each wet tension test mixture.

Example 1
Step 1: A random vessel of ethylene oxide and propylene oxide (number average molecular weight 5000, hydroxyl value 22.08 mgKOH / g, manufactured by ADEKA Co., Ltd.) in a reaction vessel (internal volume 220 L) equipped with a paddle blade type stirrer, a fractionation condenser and a thermometer (Product name `` ADEKA Polyether PR-5007 '') 50.00 kg, diphenyl carbonate 2.12 kg, 1.0 M potassium tert-butoxide / tert-butanol solution 10 mL was added, and the temperature was raised to 80 ° C. with stirring at 30 r / min And heated for 1 hour. While continuing to stir, the temperature was further raised to 100 ° C. and heated for 1 hour, then further heated to 120 ° C. and heated for 1 hour. Thereafter, while maintaining the temperature at 120 ° C., the pressure was reduced to 6.7 kPa (absolute pressure) and held for 1 hour, and then further reduced to 0.67 kPa (absolute pressure) and held for 1 hour. Thereafter, while maintaining the pressure at 0.67 kPa (absolute pressure), the temperature was raised stepwise to 140 ° C. (held for 1 hour), 160 ° C. (held for 1 hour), and 180 ° C. (held for 6 hours). Next, the temperature was lowered to 160 ° C. and held for 4 hours, then the temperature was lowered to 50 ° C., the pressure was returned to normal pressure, and 115 kg of ethanol was added to the reaction vessel. Twenty-two hours after the addition of ethanol, a 30 wt% polyether polycarbonate solution was withdrawn from the reaction vessel. The resulting polyether polycarbonate had a weight average molecular weight Mw of 190,000.

  500 g of the 30 wt% polyether polycarbonate solution thus obtained was placed in a 2 L volume plastic bottle, and 1000 g of ethanol was added to the solution. The plastic bottle was shaken up and down to mix. The polyether polycarbonate concentration and the phenol concentration of the obtained polyether polycarbonate solution are shown in Table 1.

Step 2: Into a 200 mL Erlenmeyer flask, 10 g of activated carbon (Filtrasorb 600, Mitsubishi Chemical Calgon, average pore size: 0.38 nm, wetting index: 56 mN / m, specific surface area 730 m ² / g), the polyether obtained in Step 1 100 g of the polycarbonate solution was added, and the mixture was stirred at 25 ° C. using a magnetic stirrer for 21 hours. After 21 hours, the activated carbon and the polyether polycarbonate solution were separated by filtration, and the polyether polycarbonate solution was recovered. Table 1 shows the polyether polycarbonate concentration and the phenol concentration of the recovered solution.

Example 2
Step 1: The polyether polycarbonate solution obtained in Step 1 of Example 1 was used.
Step 2: Activated carbon (GW10 / 32 made by Kuraray Chemical Co., average pore size: 0.30 nm, wetting index: 60 mN / m, specific surface area 1100 m ² / g) 10 g in the Erlenmeyer flask with a volume of 200 mL, the poly obtained in Step 1 100 g of an ether polycarbonate solution was added, and the mixture was stirred at 25 ° C. using a magnetic stirrer for 15.5 hours. After 15.5 hours, the activated carbon and the polyether polycarbonate solution were separated by filtration, and the polyether polycarbonate solution was recovered. Table 1 shows the polyether polycarbonate concentration and the phenol concentration of the recovered solution.

Example 3
Step 1: The polyether polycarbonate solution obtained in Step 1 of Example 1 was used.
Step 2: 490 g of the polyether polycarbonate solution obtained in Step 1 is filled with 41 g of activated carbon (Filtrasorb 600 manufactured by Mitsubishi Chemical Calgon, average pore size: 0.38 nm, wetting index: 56 mN / m, specific surface area 730 m ² / g) A column (inner diameter: 20 mm, activated carbon volume: 75 mL) was passed through at a flow rate of a space velocity of 1.0 hr ⁻¹ . Table 1 shows the polyether polycarbonate concentration and phenol concentration of the polyether polycarbonate solution after passing through the column.

Comparative Example 1
Step 1: The polyether polycarbonate solution obtained in Step 1 of Example 1 was used.
Step 2: Activated carbon (KW10 / 32, Kuraray Chemical Co., Ltd., average pore size: 0.55 nm, wetting index: 70 mN / m, specific surface area 1090 m ² / g) 10 g, obtained in Step 1 in a 200 mL Erlenmeyer flask 100 g of an ether polycarbonate solution was added, and the mixture was stirred at 25 ° C. using a magnetic stirrer for 23 hours. After 23 hours, the activated carbon and the polyether polycarbonate solution were separated by filtration, and the polyether polycarbonate solution was recovered. Table 1 shows the polyether polycarbonate concentration and the phenol concentration of the recovered solution.

Comparative Example 2
Step 1: The polyether polycarbonate solution obtained in Step 1 of Example 1 was used.
Step 2: In a Erlenmeyer flask with a volume of 200 mL, 10 g of activated carbon (SW manufactured by Kuraray Chemical Co., Ltd., average pore diameter: 0.50 nm, wetting index: 70 mN / m, specific surface area 1090 m ² / g), polyether polycarbonate obtained in Step 1 100 g of the solution was added, and the mixture was stirred at 25 ° C. using a magnetic stirrer for 21 hours. After 21 hours, the activated carbon and the polyether polycarbonate solution were separated by filtration, and the polyether polycarbonate solution was recovered. Table 1 shows the polyether polycarbonate concentration and the phenol concentration of the recovered solution.

Comparative Example 3
Step 1: The polyether polycarbonate solution obtained in Step 1 of Example 1 was used.
Step 2: Activated carbon (GLC10 / 32 manufactured by Kuraray Chemical Co., Ltd., average pore size: 2.00 nm, wetting index: 73 mN / m, specific surface area 1740 m ² / g) 10 g in the Erlenmeyer flask with a volume of 200 mL, 100 g of an ether polycarbonate solution was added, and the mixture was stirred at 25 ° C. for 15 hours using a magnetic stirrer. After 15 hours, the activated carbon and the polyether polycarbonate solution were separated by filtration, and the polyether polycarbonate solution was recovered. Table 1 shows the polyether polycarbonate concentration and the phenol concentration of the recovered solution.

Claims (5)

A process for producing a polyether polycarbonate comprising the following steps 1 and 2.
Step 1: Transesterification of carbonate ester and polyether diol and polycondensation Step 2: The product obtained in Step 1 has an average pore diameter of 1.0 nm or less and a wetting index of 65 mN / m or less. Process of contact with activated carbon   The method for producing a polyether polycarbonate according to claim 1, wherein the product obtained in step 1 contains a by-product having a hydroxyl group.   The method for producing a polyether polycarbonate according to claim 2, wherein the carbonate used in Step 1 is a carbonate of an aromatic alcohol, and the by-product is an aromatic compound having a hydroxyl group.   The method for producing a polyether polycarbonate according to claim 2 or 3, wherein the carbonate used in Step 1 is a carbonate of phenol and the by-product is phenol.   The method for producing a polyether polycarbonate according to any one of claims 2 to 4, wherein in step 2, the content of by-products having a hydroxyl group is reduced to 20 mg / kg or less with respect to the polyether polycarbonate.