WO2010073512A1 - グリコリドの製造方法 - Google Patents
グリコリドの製造方法 Download PDFInfo
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- WO2010073512A1 WO2010073512A1 PCT/JP2009/006713 JP2009006713W WO2010073512A1 WO 2010073512 A1 WO2010073512 A1 WO 2010073512A1 JP 2009006713 W JP2009006713 W JP 2009006713W WO 2010073512 A1 WO2010073512 A1 WO 2010073512A1
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- glycolide
- glycolic acid
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- acid oligomer
- organic solvent
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D319/00—Heterocyclic compounds containing six-membered rings having two oxygen atoms as the only ring hetero atoms
- C07D319/10—1,4-Dioxanes; Hydrogenated 1,4-dioxanes
- C07D319/12—1,4-Dioxanes; Hydrogenated 1,4-dioxanes not condensed with other rings
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- the present invention relates to a method for producing glycolide having a high purity by a depolymerization method in a solution phase of a glycolic acid oligomer.
- Polyglycolic acid is a resin material with excellent biodegradability, gas barrier properties, strength, etc., medical polymer materials such as sutures and artificial skin; packaging materials such as bottles and films; injection molded products, fibers, and vapor deposition It is used in a wide range of technical fields as resin materials for various industrial products such as films and fishing lines.
- Polyglycolic acid is a polymer having a repeating unit having a structure formed by dehydration polycondensation of glycolic acid.
- the method of dehydrating polycondensation of glycolic acid only yields a low polymerization degree polyglycolic acid having a weight average molecular weight of 20,000 or less.
- the polyglycolic acid having a low degree of polymerization is generally called a glycolic acid oligomer and has insufficient strength, melt processability, gas barrier properties, and the like.
- Polyglycolic acid having a low degree of polymerization has a too high degradation rate in a natural environment or in vivo, and cannot satisfy the durability requirement when applied to many applications.
- glycolide According to the method for ring-opening polymerization of glycolide, it is easy to control the polymerization degree of polyglycolic acid, and it is possible to synthesize polyglycolic acid having a high polymerization degree.
- Glycolide is a cyclic ester compound having a cyclic dimer structure in which two molecules of water are eliminated from two molecules of glycolic acid.
- glycolide cannot be synthesized even if glycolic acid is subjected to a dehydration reaction, and only low-polymerization polyglycolic acid (glycolic acid oligomer) is obtained.
- a typical method for producing glycolide is a depolymerization method of glycolic acid oligomers. Specifically, the following reaction formula 4
- glycolic acid is polycondensed to synthesize a glycolic acid oligomer having a low polymerization degree. Then, the following reaction formula 5
- glycolide is synthesized by depolymerizing the glycolic acid oligomer.
- ring-opening polymerization of glycolide the following formula 6
- polyglycolic acid can be produced.
- polyglycolic acid having a high degree of polymerization can be synthesized, and the degree of polymerization can be easily controlled.
- Solution phase depolymerization is a method in which a mixture containing glycolic acid oligomer and a high-boiling polar organic solvent is heated to form a solution phase of glycolic acid oligomer, and heating is continued in that state to perform depolymerization. It is.
- a solubilizer is contained in the mixture.
- JP-A-9-328481 Patent Document 1
- an ⁇ -hydroxycarboxylic acid oligomer such as glycolic acid oligomer is dissolved by heating in a high-boiling polar organic solvent, and heating is continued in this state for depolymerization.
- a method for producing a cyclic dimer ester in which the produced cyclic dimer ester is distilled together with a high-boiling polar organic solvent and the cyclic dimer ester (for example, glycolide) is recovered from the distillate. Yes.
- Patent Document 2 a mixture containing an aliphatic polyester such as low molecular weight polyglycolic acid and a specific polyalkylene glycol ether is brought to a temperature at which depolymerization of the aliphatic polyester occurs.
- the aliphatic polyester is depolymerized in a state of being heated and in a uniform solution phase, and the cyclic ester generated by the depolymerization is distilled together with the polyalkylene glycol ether, and the cyclic ester (for example, A method for producing a cyclic ester for recovering glycolide) has been proposed.
- JP 2004-523596 A discloses a depolymerization reaction system containing a glycolic acid oligomer and a high-boiling polar organic solvent, in which a glycolic acid oligomer or a glycolic acid oligomer and a high-boiling polarity are continuously or intermittently added.
- a process for producing glycolide is disclosed in which a depolymerization reaction is continuously performed while a mixture with an organic solvent is added.
- the depolymerization reaction in addition to enabling mass production of glycolide, the depolymerization reaction can be carried out stably.
- the method disclosed in Patent Document 3 even if the depolymerization reaction is continuously performed in the same reaction vessel, the production rate of glycolide due to impurities accumulated in the depolymerization reaction system is reduced. Generation of heavy materials can be suppressed.
- the glycolic acid oligomer is continuously or intermittently introduced into a depolymerization reaction system containing a glycolic acid oligomer and a high-boiling polar organic solvent.
- the depolymerization reaction is continuously performed in the same apparatus, the continuous operation can be performed for a relatively long period of time.
- the lines such as piping and heat exchangers are blocked.
- the mixture containing the glycolic acid oligomer and the high boiling polar organic solvent in the reaction tank is heated to perform depolymerization, and the produced glycolide is co-distilled with the high boiling polar organic solvent.
- the distillate is led out of the depolymerization reaction system through lines such as piping and heat exchangers.
- the depolymerization reaction is usually carried out under reduced pressure.
- the distillate is cooled by a heat exchanger and liquefied.
- Glycolide is recovered from the liquid co-distillate.
- the high boiling polar organic solvent contained in the co-distillate is refluxed into the depolymerization reaction system.
- a new glycolic acid oligomer is added to the depolymerization reaction system.
- glycolide obtained by depolymerization of glycolic acid oligomers is not sufficiently high in purity and is called crude glycolide.
- Glycolide used as a monomer for ring-opening polymerization is required to have a high purity of 99.9% or more. Therefore, the crude glycolide obtained by depolymerization is highly purified by a purification treatment such as recrystallization or washing. If the purity of the crude glycolide is low, the purification cost cannot be reduced, and in addition, the purification process may cause blockage of the line.
- the main cause of line blockage in the depolymerization reaction is that impurities contained in the fraction distilled from the depolymerization reaction system act as a polymerization initiator, and glycolide produced and distilled by depolymerization is an oligomer in the middle of the line. It is estimated that this oligomer is attached to the surface of each part of the apparatus. In fact, the crude glycolide obtained by depolymerization contains various impurities.
- glycolic acid glycolic acid chain dimer, glycolic acid chain trimer and the like are detected. It is presumed that such impurities include those contained in glycolic acid oligomers and those generated during the depolymerization reaction of glycolic acid oligomers.
- An object of the present invention is to provide a new production method capable of obtaining glycolide with high purity in a method for producing glycolide by depolymerization of glycolic acid oligomers in a solution phase.
- the purity of glycolide obtained from the co-distillate in the initial stage is particularly low. The reason for this is presumed to be that low boiling point impurities are easily distilled off in the initial stage.
- the purity of glycolide tends to be improved.
- glycolic acid oligomers are continuously or intermittently added to the depolymerization reaction system and the continuous operation is performed, the purity of glycolide obtained immediately after the addition decreases again.
- glycolic acid oligomers or glycolic acid oligomers supplied to the depolymerization reaction and high-boiling polar organics It is necessary that the mixture containing the solvent is difficult to distill off impurities.
- the present inventors have paid attention to the fact that it is extremely important to produce high-purity glycolide in order to suppress the blockage of the line and realize a stable continuous operation of the depolymerization reaction. If high-purity glycolide can be obtained by depolymerization reaction, glycolide distilled from the depolymerization reaction system will be oligomerized under the influence of impurities in the middle of the line and adhere to the surface of lines such as piping and heat exchangers. And can be blocked. If high-purity glycolide can be obtained by depolymerization, the purification cost can be suppressed, and line blockage in the purification process can be prevented.
- the present inventors include a step of depolymerizing the glycolic acid oligomer in a solution phase by heating a mixture containing the glycolic acid oligomer and the high-boiling polar organic solvent.
- a high-purity glycolide having a purity of 99.0% or more can be obtained by adopting a method in which the mixture is totally refluxed and then depolymerized with glycolic acid oligomers.
- high-purity glycolide can be obtained in the subsequent depolymerization reaction step by carrying out the total reflux treatment is a surprising result that cannot be expected from the technical common sense.
- Obtaining high purity glycolide means that the amount of impurities contained in the distillate distilled from the depolymerization reaction system is reduced. When the amount of impurities in the distillate passing through the line is reduced, blockage of the line due to oligomerization of glycolide due to the impurities is suppressed. When high-purity glycolide is obtained by depolymerization, the load in the purification process is reduced, and the blockage of the purification line is also suppressed.
- the present invention has been completed based on these findings.
- a method for producing glycolide comprising a step of depolymerizing the glycolic acid oligomer in a solution phase by heating a mixture containing the glycolic acid oligomer and the high-boiling polar organic solvent, (1) A mixture containing a glycolic acid oligomer and a high-boiling polar organic solvent having a boiling point in the range of 230 to 450 ° C.
- step 1 in which a total reflux treatment is performed under a reflux time within a range of 0.1 to 20 hours under a condition in which substantially all of the distillate distilled from the system is refluxed into the reflux system;
- the glycolic acid oligomer is depolymerized under normal pressure or reduced pressure in a mixture obtained by adding the high-boiling polar organic solvent to the glycolic acid oligomer component collected from the mixture after the total reflux treatment or the mixture after the total reflux treatment.
- the glycolic acid oligomer is depolymerized in a solution phase by heating to a temperature at which the glycolide is depolymerized together with the high-boiling polar organic solvent from the depolymerization reaction system containing the mixture.
- a process for producing glycolide comprising the steps of:
- high purity glycolide can be produced by depolymerization of glycolic acid oligomer in the solution phase. If the production method of the present invention is applied to a glycolide depolymerization step by continuous operation, blockage of the line can be suppressed, so that long-term operability (long run property) can be remarkably improved. High-purity glycolide also contributes to reducing the load in the subsequent purification process and suppressing line blockage. As a result, according to the production method of the present invention, the cost of glycolide can be reduced, and as a result, the cost of polyglycolic acid can be reduced.
- FIG. 1 is an explanatory diagram showing an example of an apparatus for performing total reflux.
- FIG. 2 is an explanatory diagram showing an example of an apparatus for performing a depolymerization reaction.
- FIG. 3 is an explanatory diagram showing an example of an apparatus used for continuous operation of the depolymerization reaction.
- Glycolic acid oligomer is a polyglycolic acid having a weight average molecular weight (Mw) of 20,000 or less, and often 10,000 or less, and a low polymerization degree (low molecular weight).
- the glycolic acid oligomer can be synthesized by polycondensation of glycolic acid.
- Glycolic acid may be in the form of its ester (eg, lower alkyl ester) or salt (eg, sodium salt).
- Glycolic acid is heated to a temperature of usually 100 to 250 ° C., preferably 140 to 230 ° C. in the presence of a polycondensation catalyst or a transesterification catalyst as required, and distillation of low molecular weight substances such as water and alcohol is substantially performed.
- the polycondensation reaction is carried out until it disappears.
- the produced glycolic acid oligomer can be used as a raw material as it is.
- the glycolic acid oligomer obtained by synthesis can be used after washing with a non-soluble solvent such as benzene or toluene to remove unreacted substances, low polymer or catalyst.
- the glycolic acid oligomer has a melting point (Tm) of usually 140 ° C. or higher, preferably 160 ° C. or higher, more preferably 180 ° C. or higher from the viewpoint of the yield of glycolide in the depolymerization reaction.
- Tm melting point
- the melting point is a temperature detected as an endothermic peak temperature when the temperature is raised at a rate of 10 ° C./min in an inert gas atmosphere using a differential scanning calorimeter (DSC).
- DSC differential scanning calorimeter
- the upper limit of the melting point is about 220 ° C.
- High-boiling polar organic solvent A high-boiling polar organic solvent is used as a medium in the total reflux treatment step and the depolymerization reaction step.
- a high boiling polar organic solvent having a boiling point within the range of 230 to 450 ° C. is used.
- the high-boiling polar organic solvent is used as a solvent for the depolymerization reaction, and also plays a role of causing the glycolide to accompany the outside of the depolymerization reaction system by co-distilling with the generated glycolide.
- co-distilling the high boiling polar organic solvent with glycolide it is possible to prevent glycolide from adhering to the inner wall surface of the line.
- the boiling point of the high boiling polar organic solvent is preferably in the range of 235 to 450 ° C, more preferably 255 to 430 ° C, and most preferably 280 to 420 ° C.
- the boiling point of the high-boiling polar organic solvent is a value under normal pressure. When the boiling point is measured under reduced pressure, it is converted to a value under normal pressure.
- the molecular weight of the high-boiling polar organic solvent is preferably in the range of 150 to 450, more preferably 180 to 420, and even more preferably 200 to 400. If the molecular weight of the high-boiling polar organic solvent is too small or too large, it is not preferable because co-distillation with glycolide becomes difficult.
- the total reflux treatment step of the present invention the total reflux treatment is carried out smoothly, and in order to efficiently achieve the effect of reducing impurities by the total reflux treatment, the depolymerization reaction in the subsequent depolymerization reaction step is further performed.
- a high boiling polar organic solvent is used as a medium.
- Examples of the high boiling polar organic solvent include aromatic dicarboxylic acid diesters, aromatic carboxylic acid esters, aliphatic dicarboxylic acid diesters, polyalkylene glycol diethers, aromatic dicarboxylic acid dialkoxyalkyl esters, and aliphatic dicarboxylic acid dialkoxyalkyls.
- Examples include esters, polyalkylene glycol diesters, and aromatic phosphate esters.
- aromatic dicarboxylic acid diesters aromatic carboxylic acid esters, aliphatic dicarboxylic acid diesters, and polyalkylene glycol diethers are preferred, and polyalkylene glycol diethers are less prone to thermal degradation. Is more preferable.
- aromatic dicarboxylic acid diester examples include phthalic acid esters such as dibutyl phthalate, dioctyl phthalate, dibenzyl phthalate, and benzyl butyl phthalate.
- aromatic carboxylic acid ester examples include benzoic acid esters such as benzyl benzoate.
- aliphatic dicarboxylic acid diesters include adipic acid esters such as dioctyl adipate; sebacic acid esters such as dibutyl sebacate.
- R 1 represents a methylene group or a linear or branched alkylene group having 2 to 8 carbon atoms.
- X 1 represents a hydrocarbon group.
- Y represents an alkyl group having 2 to 20 carbon atoms.
- p represents an integer of 1 or more, and when p is 2 or more, a plurality of R 1 may be the same or different.
- polyalkylene glycol diether examples include diethylene glycol dibutyl ether, diethylene glycol dihexyl ether, diethylene glycol dioctyl ether, diethylene glycol butyl 2-chlorophenyl ether, triethylene glycol diethyl ether, triethylene glycol dipropyl ether, triethylene glycol dibutyl ether, triethylene glycol dibutyl ether, Ethylene glycol dihexyl ether, triethylene glycol dioctyl ether, triethylene glycol butyl octyl ether, triethylene glycol butyl decyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol dipropyl ether, tetraethylene glycol dibutyl ether, tetraethylene group Coal dihexyl ether, tetraethylene glycol dioctyl ether, diethylene glycol butyl hexyl ether, tri
- polyalkylene glycol dialkyl ether is preferable and diethylene glycol dialkyl ether, triethylene glycol dialkyl ether, and tetraethylene glycol dialkyl ether are more preferable because they are easy to synthesize and hardly cause thermal degradation.
- the polyalkylene glycol diether preferably has a glycolide solubility at 25 ° C. in the range of 0.1 to 10%.
- the solubility of glycolide is expressed as a percentage of the mass (g) of glycolide with respect to the volume (ml) of polyalkylene glycol diether when glycolide is dissolved in a polyalkylene glycol diether at 25 ° C. until saturation.
- the solubility is too low, glycolide distilled together with the polyalkylene glycol diether precipitates, and the recovery line is likely to be blocked, which is not preferable. If the solubility is too high, in order to recover glycolide from the co-distillate obtained by the depolymerization reaction, for example, the co-distillate is cooled to a temperature of 0 ° C. or lower, or is not soluble in the co-distillate. It may be necessary to isolate glycolide, such as by adding a solvent.
- tetraethylene glycol dibutyl ether and triethylene glycol butyl octyl ether are more preferable from the viewpoints of ease of synthesis, heat deterioration resistance, depolymerization reactivity, glycolide recoverability, and the like.
- the high-boiling polar organic solvent is usually used in a ratio of 0.3 to 50 times, preferably 0.5 to 20 times, based on mass with respect to the glycolic acid oligomer. If the proportion of the high-boiling polar organic solvent is too small, the total reflux treatment becomes difficult, and the glycol in the mixture containing the glycolic acid oligomer and the high-boiling polar organic solvent under the depolymerization temperature condition of the glycolic acid oligomer. The ratio of the solution phase of the acid oligomer decreases, and the depolymerization reactivity of the glycolic acid oligomer decreases. If the proportion of the high-boiling polar organic solvent is too large, the thermal efficiency in the total reflux treatment and the depolymerization reaction is lowered, and the productivity of glycolide by the depolymerization reaction is also lowered.
- Solubilizer In the production method of the present invention, a high-boiling polar organic solvent can be used alone in the total reflux treatment step and the depolymerization reaction step, but it is preferable to use a solubilizer in combination. It has been found that the use of a solubilizer in the total reflux process further improves the purity of glycolide obtained by depolymerization. When a solubilizer is used in the depolymerization reaction step, depolymerization of the glycolic acid oligomer in the solution phase efficiently proceeds.
- the solubilizer used in the present invention is preferably a compound satisfying any one or more of the following requirements.
- the compound is compatible or soluble in a high-boiling polar organic solvent such as polyalkylene glycol diether.
- a high-boiling polar organic solvent such as polyalkylene glycol diether.
- Any compound that is compatible or soluble in a high-boiling polar organic solvent may be liquid or solid at room temperature.
- a compound having a functional group such as OH group, COOH group, and CONH group.
- Affinity with glycolic acid oligomers is higher than that of high boiling polar organic solvents.
- the affinity between the solubilizer and the glycolic acid oligomer is determined by heating a mixture of the glycolic acid oligomer and the high-boiling polar organic solvent to a temperature of 230 ° C. or more to form a uniform solution phase. Add further to increase the concentration until the mixture no longer forms a homogeneous solution phase, add solubilizer to it and confirm by visual observation whether a homogeneous solution phase is formed again. Can do.
- the solubilizing agent When a compound having a boiling point higher than the boiling point of the high-boiling polar organic solvent used in the depolymerization reaction is used as the solubilizing agent, the glycolide and the high-boiling polar organic solvent are not distilled together with the glycolide and the distillation amount is reduced. This is preferable because it is extremely small. In many cases, good results can be obtained by using a compound having a boiling point of 450 ° C. or higher as a solubilizer. Even if the compound has a boiling point lower than that of the high-boiling polar organic solvent used as the depolymerization solvent, alcohols and the like can be suitably used as the solubilizer.
- solubilizers monohydric alcohols, polyhydric alcohols, phenols, monohydric aliphatic carboxylic acids, polyhydric aliphatic carboxylic acids, aliphatic amides, aliphatic imides each having a boiling point of 180 ° C. or higher
- At least one non-basic organic compound selected from the group consisting of polyalkylene glycol diethers having a molecular weight exceeding 450 and sulfonic acids is preferred.
- monohydric alcohols and polyhydric alcohols are particularly effective as solubilizers.
- monohydric or polyhydric alcohols monohydric or polyhydric alcohols having a boiling point of 180 ° C. or higher, preferably 200 ° C. or higher, more preferably 230 ° C. or higher, particularly preferably 250 ° C. or higher can be used.
- monohydric or polyhydric alcohols examples include aliphatic alcohols such as decanol, tridecanol, decanediol, ethylene glycol, propylene glycol and glycerin; aromatic alcohols such as cresol, chlorophenol and naphthyl alcohol; polyalkylene glycol; polyalkylene glycol Examples include monoethers.
- R 2 represents a methylene group or a linear or branched alkylene group having 2 to 8 carbon atoms.
- X 2 represents a hydrocarbon group.
- Q represents an integer of 1 or more.
- Q When R is 2 or more, the plurality of R 2 may be the same or different.
- polyalkylene glycol monoether examples include polyethylene glycol monomethyl ether, polyethylene glycol monoethyl ether, polyethylene glycol monopropyl ether, polyethylene glycol monobutyl ether, polyethylene glycol monohexyl ether, polyethylene glycol monooctyl ether, polyethylene glycol monodecyl ether.
- Polyethylene glycol monoethers such as polyethylene glycol monolauryl ether; in the polyethylene glycol monoethers, polyalkylene glycol monoethers such as polypropylene glycol monoethers and polybutylene glycol monoethers in which ethyleneoxy groups are replaced with propyleneoxy groups or butyleneoxy groups ether And the like.
- the polyalkylene glycol monoether preferably has an alkyl group having 1 to 18 carbon atoms as its ether group, and more preferably has an alkyl group having 6 to 18 carbon atoms. These can be used alone or in combination of two or more.
- polyalkylene glycol monoethers polyethylene glycol monoalkyl ethers such as triethylene glycol monooctyl ether are preferable.
- polyalkylene glycol monoether When polyalkylene glycol monoether is used as a solubilizing agent, these compounds have a high boiling point, so that they hardly distill. In addition, since polyalkylene glycol monoether has high solubility of glycolic acid oligomers, when this is used as a solubilizer, the depolymerization reaction of glycolic acid oligomers proceeds rapidly. When polyalkylene glycol monoether is used as a solubilizer, the cleaning effect on the can wall (reaction vessel inner wall) is particularly excellent.
- R 3 represents a methylene group or a linear or branched alkylene group having 2 to 8 carbon atoms.
- R represents an integer of 1 or more. When r is 2 or more, a plurality of R 3 May be the same or different.
- polyalkylene glycol examples include polyethylene glycol, polypropylene glycol, polybutylene glycol and the like. These can be used alone or in combination of two or more.
- Higher-boiling polar organic solvents used in the total reflux treatment step and the depolymerization reaction step have higher affinity with glycolic acid oligomers, and high molecular weight and higher boiling polyalkylene glycol diethers can be used as solubilizers.
- polyalkylene glycol diethers suitable as a solubilizer include polyethylene glycol dimethyl ether # 500 (average molecular weight 500), polyethylene glycol dimethyl ether # 2000 (average molecular weight 2000), and the like.
- the polyalkylene glycol diether used as the solubilizer has a molecular weight exceeding 450.
- this molecular weight may distill together with glycolide during the depolymerization reaction, and may not function sufficiently as a solubilizer that maintains the solubility of the glycolic acid oligomer in the depolymerization reaction system.
- solubilizing agent acts in the middle of the molecular chain of the glycolic acid oligomer.
- Action to increase the depolymerization reaction point by binding to one end of glycolic acid oligomer 6) Acting in the middle of glycolic acid oligomer and cleaved molecular chain end 7) It is presumed that the depolymerization reaction point is increased by binding to 7) and that these combined actions are performed.
- solubilizer When a solubilizer is used, it is usually used at a ratio of 0.1 to 500 parts by mass, preferably 1 to 300 parts by mass with respect to 100 parts by mass of the glycolic acid oligomer. When the use ratio of the solubilizer is too small, the effect of improving the solubility by the solubilizer cannot be sufficiently obtained. If the proportion of solubilizer used is too large, it will be costly to recover the solubilizer and is not economical.
- the glycolic acid oligomer is depolymerized by heating the mixture containing the glycolic acid oligomer and the high-boiling polar organic solvent by a solution phase depolymerization method. Prior to this depolymerization reaction step, Then, the mixture is totally refluxed.
- a mixture containing a glycolic acid oligomer and a high-boiling polar organic solvent having a boiling point in the range of 230 to 450 ° C. is refluxed by heating under normal pressure or reduced pressure.
- the total reflux treatment is performed under a reflux time in the range of 0.1 to 20 hours under the condition that substantially the entire amount of the distillate distilled from the reflux system is refluxed into the reflux system.
- the high-boiling polar organic solvent is usually used in a ratio of 0.3 to 50 times, preferably 0.5 to 20 times, based on mass with respect to the glycolic acid oligomer. If the proportion of the high boiling polar organic solvent is too small, the total reflux treatment becomes difficult. When the ratio of the high boiling polar organic solvent becomes too large, the thermal efficiency in the total reflux treatment is lowered.
- the mixture used in the total reflux treatment step is a monohydric alcohol having a boiling point of 180 ° C. or higher, a polyhydric alcohol, a phenol, At least one non-basic organic compound selected from the group consisting of polyvalent aliphatic carboxylic acids, polyvalent aliphatic carboxylic acids, aliphatic amides, aliphatic imides, polyalkylene glycol diethers having a molecular weight exceeding 450, and sulfonic acids A mixture further containing a compound is preferable.
- solubilizer By using a solubilizer, higher-purity glycolide can be obtained in the depolymerization reaction step after the total reflux treatment.
- the solubilizer is generally used in a proportion of 0.1 to 500 parts by weight, preferably 1 to 300 parts by weight, per 100 parts by weight of the glycolic acid oligomer.
- the molar ratio of glycolic acid oligomer to solubilizer is preferably 1 to 99, more preferably 3 to 70, and even more preferably. Is adjusted within the range of 5 to 50, a higher purity glycolide can be obtained.
- the total reflux treatment can be performed under normal pressure or reduced pressure, but since a high boiling polar organic solvent is used, it is preferable to perform under reduced pressure in order to smoothly perform the total reflux treatment.
- the degree of reduced pressure is preferably in the range of 1 to 30 kPa, more preferably 1.5 to 20 kPa, still more preferably 2 to 10 kPa, and particularly preferably 2.5 to 8 kPa.
- the total reflux treatment can be carried out using a reaction vessel (reaction tank) equipped with a reflux condenser (reflux cooling tower).
- Stirring means such as a stirrer equipped with a stirring blade is disposed inside the reaction container, and heating means such as a heater is disposed outside the reaction container.
- a glycolic acid oligomer, a high-boiling polar organic solvent, and, if necessary, a solubilizing agent are charged into the reaction vessel, and the mixture containing these is heated with stirring.
- FIG. 1 shows a schematic diagram of an example of a reflux apparatus.
- the reaction vessel 1 is provided with a stirring device 2 equipped with a stirring blade, and a glycolic acid oligomer, a high-boiling polar organic solvent, and optionally a solubilizing agent are introduced into the reaction vessel 1 from the raw material inlet 3
- a reflux system consisting of 4 is formed.
- Heating means 5 such as a mantle heater is disposed outside the reaction vessel 1, and the mixture 4 is heated to dissolve the glycolic acid oligomer to form a solution phase.
- the distillate containing the high-boiling polar organic solvent from the reflux system reaches the reflux cooling pipe 8 via the pipe 7 from the distillation column 6, where it is cooled and refluxed into the original reflux system.
- Low-boiling substances passing through the reflux cooling pipe 8 are trapped in a first cooling trap (for example, an ice bath trap) 10 via a pipe 9.
- the pipe 15 is connected to a vacuum device (vacuum pump) 16.
- the first cooling trap 10 is connected to a second cooling trap (for example, a dry ice strap) through a pipe 11, a valve 12, and a pipe 13, and second cooling is performed for low-boiling substances that have not been captured by the first cooling trap. It is configured to trap by a trap.
- the distillation column 6 serves to adjust the temperature of the distillate so that the distillate smoothly reaches the reflux condenser 8 from the pipe 7.
- the heating temperature is set to a temperature at which the high boiling polar organic solvent is distilled.
- the heating temperature varies depending on the reflux conditions such as the type of the high-boiling polar organic solvent and the degree of reduced pressure. By controlling these reflux conditions, it is usually 210 to 350 ° C., preferably 220 to 300 ° C., more preferably 225 to It is desirable to set within the range of 280 ° C.
- the total reflux treatment is desirably carried out under the condition that the residual ratio of the melt phase of the glycolic acid oligomer is 0.5 or less, preferably 0.3 or less, more preferably zero.
- the residual ratio of the melt phase of glycolic acid oligomer is the actual value when the volume of glycolic acid oligomer formed in a solvent that is substantially insoluble in glycolic acid oligomer such as liquid paraffin is 1
- the total reflux treatment it is particularly preferable to carry out the total reflux treatment in a state where the residual ratio of the melt phase of the glycolic acid oligomer is substantially zero and a uniform solution phase is formed in order to obtain high-purity glycolide.
- the glycolic acid oligomer forms a uniform solution phase in the heated mixture, the effect of the total reflux treatment can be enhanced. Therefore, it is preferable to use a solubilizer.
- the total reflux treatment means that all fractions distilled during the reflux treatment are cooled, and substantially all of the distillate is returned to the reflux system composed of the original mixture. Therefore, during the total reflux treatment, distillates such as high-boiling polar organic solvents are not discharged out of the reflux system. However, when the total reflux treatment is performed under reduced pressure, a part of low boiling point substances such as water may be sucked by a vacuum device (vacuum pump) and discharged out of the reflux system. The discharged low boiling point substances are captured by a cooled trap device. It is preferable to remove low-boiling substances such as water because they are impurities.
- substantially the total amount of the distillate means that a small amount of low-boiling substances other than the high-boiling polar organic solvent, glycolide, and the solubilizer are sucked by the vacuum apparatus and removed from the reflux system. Is meant to include
- the cooling temperature of the reflux condenser is usually controlled within the range of 70 to 150 ° C, preferably 75 to 120 ° C, more preferably 80 to 100 ° C. If the cooling temperature is too low, the removability of low-boiling substances such as water is deteriorated. Since it is presumed that a part of the glycolic acid oligomer is converted to glycolide under the total reflux condition, if the cooling temperature is too high, the distilled glycolide is sucked by the vacuum device and discharged out of the reflux system.
- the total reflux treatment time is in the range of 0.1 to 20 hours, preferably 0.3 to 15 hours, more preferably 0.5 to 10 hours, and particularly preferably 0.8 to 5 hours. If the total reflux time is too short, the effect of the total reflux treatment becomes insufficient, and it becomes difficult to obtain high-purity glycolide in the depolymerization reaction step. If the total reflux treatment time is too long, the effect of the total reflux treatment becomes saturated, and the thermal efficiency and productivity decrease.
- Depolymerization reaction step In the depolymerization reaction step, a mixture obtained by adding a high-boiling polar organic solvent to a glycolic acid oligomer component recovered from a mixture after total reflux treatment or a mixture after total reflux treatment is subjected to glycol under normal pressure or reduced pressure.
- the glycolic acid oligomer is depolymerized in a solution phase by heating to a temperature at which the acid oligomer is depolymerized, and glycolide generated by depolymerization from the depolymerization reaction system containing the mixture is dissolved together with a high-boiling polar organic solvent. Co-distilled outside the polymerization reaction system.
- the mixture after the total reflux treatment can be used.
- the mixture after the total reflux treatment can be used as it is, but a high-boiling polar organic solvent or a solubilizing agent may be added if desired.
- the depolymerization reaction system When the mixture after the total reflux treatment is used in the depolymerization reaction step, the depolymerization reaction system is used when the depolymerization reaction step is continuously carried out in the same reaction vessel (reaction tank) for a long period of time (when continuously operated). If the high-boiling polar organic solvent is not discharged outside, the high-boiling polar organic solvent and the solubilizer accumulate in the reaction vessel and overflow. In order to avoid overflow, a method of discharging the high-boiling polar organic solvent together with the produced glycolide out of the depolymerization reaction system during continuous operation is adopted.
- the solubilizer when a solubilizer that does not substantially distill off during the continuous operation of the depolymerization reaction is used, the solubilizer accumulates in the reaction vessel. In this method, the molar ratio of the glycolic acid oligomer and the solubilizer varies.
- the glycolic acid oligomer components are recovered from the mixture after the total reflux treatment. This can be added to the depolymerization reaction system. It is presumed that the glycolic acid oligomer component after the total reflux treatment contains unreacted glycolic acid oligomer and glycolide.
- the melt phase of the glycolic acid oligomer component When the melt phase of the glycolic acid oligomer component is formed in the cooling process of the mixture after the total reflux treatment, the melt phase accumulates in the lower layer due to the difference in specific gravity, so that it is easily separated from the upper high-boiling polar organic solvent. be able to.
- the glycolic acid oligomer component may be separated by a method of precipitating the glycolic acid oligomer component from the mixture after the total reflux treatment and sieving the precipitate. In the glycolic acid oligomer component recovered from the mixture after the total reflux treatment, a part of the high boiling polar organic solvent and the solubilizer used in the total reflux treatment step may remain.
- the glycolic acid oligomer component recovered from the mixture after the total reflux treatment is mixed with a high-boiling polar organic solvent and optionally a solubilizer.
- the glycolic acid oligomer component (glycolic acid oligomer component after total reflux treatment) in an amount commensurate with the amount of glycolide taken out of the depolymerization reaction system is continuously or intermittently depolymerized. Add to the system.
- the amount ratio of each component in the depolymerization reaction step is substantially the same as in the total reflux treatment step.
- the high-boiling polar organic solvent is usually used in a ratio of 0.3 to 50 times, preferably 0.5 to 20 times, based on the mass with respect to the charged glycolic acid oligomer.
- the amount ratio between the glycolic acid oligomer component and the high-boiling polar organic solvent is that of the glycolic acid oligomer at the time of charging in the total reflux step. Calculate based on quantity.
- the proportion of the high boiling polar organic solvent is too small, the ratio of the solution phase of the glycolic acid oligomer in the mixture containing the glycolic acid oligomer and the high boiling polar organic solvent under the depolymerization temperature condition of the glycolic acid oligomer It decreases (the ratio of the melt phase of the glycolic acid oligomer increases), and the depolymerization reactivity of the glycolic acid oligomer decreases. If the proportion of the high-boiling polar organic solvent becomes too large, the thermal efficiency in the depolymerization reaction is lowered, and the productivity of glycolide by the depolymerization reaction is lowered.
- the solubilizing agent When a solubilizing agent is used in the depolymerization reaction step, the solubilizing agent is generally used at a ratio of 0.1 to 500 parts by weight, preferably 1 to 300 parts by weight with respect to 100 parts by weight of the charged glycolic acid oligomer.
- the molar ratio of the charged glycolic acid oligomer to the solubilizing agent is preferably 1 to 99, more preferably 3 to 70, still more preferably. Is adjusted within the range of 5 to 50, a higher purity glycolide can be obtained.
- the solubilizer When the solubilizer accumulates in the depolymerization reaction system without distilling in the depolymerization reaction step, the molar ratio of the charged glycolic acid oligomer and the solubilizer is set large, and the solubilizer is removed by continuous operation. Even if it accumulates, it is preferable to control it to be within the range of the molar ratio. Even if the solubilizer accumulates, the molar ratio may be outside the range as long as the depolymerization reaction can be continued efficiently.
- the heating temperature at the time of depolymerization is equal to or higher than the temperature at which depolymerization of glycolic acid oligomer occurs, and is generally a temperature of 200 ° C. or higher, although it depends on the degree of pressure reduction and the type of high-boiling polar organic solvent.
- the heating temperature is usually in the range of 200 to 350 ° C, preferably 210 to 310 ° C, more preferably 220 to 300 ° C, and particularly preferably 230 to 290 ° C.
- aromatic dicarboxylic acid diesters aromatic carboxylic acid esters, aliphatic dicarboxylic acid diesters, and polyalkylene glycol diethers are preferable.
- Alkylene glycol diether is more preferred.
- the polyalkylene glycol diether the compound represented by Formula 1 is preferable.
- solubilizer used in the depolymerization reaction, monohydric alcohols, polyhydric alcohols, phenols, monovalent aliphatic carboxylic acids, polyvalent aliphatic carboxylic acids, aliphatic amides each having a boiling point of 180 ° C. or higher are used. And at least one non-basic organic compound selected from the group consisting of aliphatic imides, polyalkylene glycol diethers having a molecular weight exceeding 450, and sulfonic acids.
- polyalkylene glycol monoether represented by Formula 2 and polyalkylene glycol represented by Formula 3 are more preferable.
- the heating during the depolymerization reaction is performed under normal pressure or reduced pressure, but is preferably performed under reduced pressure of 0.1 to 90 kPa.
- the degree of reduced pressure is preferably 1 to 60 kPa, more preferably 1.5 to 40 kPa, and particularly preferably 2 to 30 kPa.
- the glycolic acid oligomer, a high-boiling polar organic solvent, and optionally a mixture containing a solubilizer are heated to form a glycolic acid oligomer solution phase. It is desirable to carry out the depolymerization reaction under conditions where the residual ratio of the melt phase of the glycolic acid oligomer is 0.5 or less, preferably 0.3 or less, more preferably zero.
- the depolymerization reaction is carried out in a substantially homogeneous solution phase state in which the residual ratio of the melt phase of the glycolic acid oligomer is substantially zero, particularly in order to efficiently obtain high purity glycolide. preferable.
- the depolymerization reaction is a reversible reaction, when glycolide is distilled from the liquid phase and discharged out of the depolymerization reaction system, the depolymerization reaction of the glycolic acid oligomer proceeds efficiently. After the depolymerization reaction, the high boiling polar organic solvent remaining in the depolymerization reaction system can be recovered by continuing the heating.
- glycolide produced by depolymerization is co-distilled out of the depolymerization reaction system together with the high-boiling polar organic solvent, and glycolide is obtained from the co-distilled co-distillate.
- the distillate is cooled by a heat exchanger (cooler) to be liquefied, and glycolide and a high boiling polar organic solvent are phase-separated in a liquid state.
- a glycolide phase glycolide layer
- the upper layer becomes a high-boiling polar organic solvent phase (a layer containing a high-boiling polar organic solvent).
- the lower layer glycolide can be separated and recovered in a liquid state.
- the cooling temperature is usually controlled within the range of 70 to 180 ° C, preferably 75 to 150 ° C, more preferably 80 to 120 ° C. If the cooling temperature is too high, side reactions such as ring-opening reactions tend to occur in the glycolide phase during the separation and recovery operation. If the cooling temperature is too low, it is difficult to separate the phases in a liquid state.
- glycolide co-distilled with the high boiling polar organic solvent passes through the solvent phase of the upper layer of the co-distillate as droplets. , Condensing into the lower glycolide phase.
- the remaining high boiling polar organic solvent phase from which glycolide has been removed from the co-distillate can be discharged out of the depolymerization reaction system and reused.
- the high-boiling polar organic solvent may be purified by adsorption on activated carbon, or may be reused after purification by distillation.
- a polyalkylene glycol diether excellent in thermal stability is used as the high-boiling polar organic solvent, almost the entire amount recovered from the co-distillate can be reused without purification.
- the co-distillate is phase-separated in a liquid state, and glycolide is separated and recovered from the glycolide phase (glycolide layer; lower layer), and the phase (upper layer) containing the high-boiling polar organic solvent is dissolved. It can be circulated in the polymerization reaction system. A phase (upper layer) containing a high-boiling polar organic solvent can be taken out and reused as it is, or after purification and reuse.
- the distillate is stored in a separation tank and phase-separated. The temperature of the separation tank is adjusted to a temperature at which the co-distillate remains liquid using a heat medium such as warm water.
- the temperature of the separation tank is usually controlled within the range of 70 to 180 ° C, preferably 75 to 150 ° C, more preferably 80 to 120 ° C.
- the separated glycolide is purified by recrystallization or washing as necessary. According to this method, it is not necessary to separate a large amount of solvent from the recovered glycolide, and the operation for separating the solvent and glycolide is simplified.
- the mother liquor excluding glycolide (the fraction containing a high-boiling polar organic solvent) can be reused almost without any steps such as purification.
- a fraction containing a high-boiling polar organic solvent may be purified by adsorbing it on activated carbon, or may be reused after purification by distillation.
- the depolymerization reaction step and the glycolide acquisition step can be performed using, for example, the apparatus shown in FIG.
- FIG. 2 is a schematic diagram showing an example of an apparatus for carrying out the depolymerization reaction.
- the reaction vessel (reaction vessel) 21 is provided with a stirring device 22 equipped with stirring blades, and glycol recovered from the mixture after the total reflux treatment or the mixture after the total reflux treatment is introduced into the reaction vessel 21 from the raw material inlet 23. Charge the acid oligomer component. When the glycolic acid oligomer component recovered from the mixture after the total reflux treatment is charged, a high-boiling polar organic solvent and, if desired, a solubilizer are also charged.
- a heating means 25 such as a mantle heater is disposed outside the reaction vessel 21, and the mixture 24 is heated to dissolve the glycolic acid oligomer to form a solution phase.
- a distillate containing glycolide and a high-boiling polar organic solvent from the depolymerization reaction system reaches the first heat exchanger 28 via the pipe 27 from the distillation column 26, and the fraction (co-distilled) cooled there.
- the product is stored in the separation tank 29.
- the distillation column 26 serves to adjust the temperature of the distillate so that the distillate smoothly reaches the first heat exchanger 28 from the pipe 27.
- the temperature of the first heat exchanger 28 is usually controlled within a range of 70 to 180 ° C, preferably 75 to 150 ° C, more preferably 80 to 120 ° C.
- the fraction passing through the first heat exchanger 28 is cooled by the second heat exchanger 31 through the pipe 30 and trapped in the first cooling trap (for example, ice bath trap) 33 through the pipe 32.
- the temperature of the second heat exchanger 31 is usually controlled within a range of 15 to 70 ° C., preferably 20 to 30 ° C.
- the pipe 38 is connected to a vacuum device (for example, a vacuum pump) 39.
- the first cooling trap 33 is connected to a second cooling trap 37 (for example, a dry ice strap) via a pipe 34, a valve 35, and a pipe 36, and low-boiling substances that are not captured by the first cooling trap 33 are Trap in the second cooling trap 37.
- the lower layer glycolide phase-separated in the separation tank 29 is taken out into the container 42 through the pipe 41.
- the upper layer in the separation tank 29 is taken out after the depolymerization reaction or taken out from a discharge port (not shown) provided in the separation layer.
- the production method of the present invention comprises the steps 1 to 3, a) a step of continuously or intermittently supplying the glycolic acid oligomer component recovered from the mixture after the total reflux treatment prepared in the step 1 or the mixture after the total reflux treatment into the depolymerization reaction system of the step 2a ; b) In step 2, the glycolic acid oligomer component recovered from the mixture after the total reflux treatment or the mixture after the total reflux treatment is added with the high-boiling polar organic solvent to the glycolic acid under normal pressure or reduced pressure.
- the glycolic acid oligomer is continuously depolymerized in a solution phase by heating to a temperature at which the oligomer is depolymerized, and glycolide generated by depolymerization from a depolymerization reaction system containing the mixture is converted to the high boiling polarity Steps b and c) of continuously co-distilling with an organic solvent out of the depolymerization reaction system; and in step 3, using the specific gravity difference between the fraction containing the high-boiling polar organic solvent and glycolide.
- step c glycolide is obtained continuously or intermittently from the lower layer of the co-distillate cooled to a liquid state, and the fraction containing the high-boiling polar organic solvent in the upper layer of the co-distillate is continuously or It can be discharged intermittently.
- step c glycolide is obtained continuously or intermittently from the lower layer of the co-distillate cooled to a liquid state, and the fraction containing the high-boiling polar organic solvent in the upper layer of the co-distillate is continuously or It can be intermittently returned to the depolymerization reaction system.
- FIG. 3 shows a main part of the depolymerization reaction apparatus, and details such as a stirring device, a heating device, a trap, and a valve are omitted.
- a mixture 302 obtained by adding a high-boiling polar organic solvent to a glycolic acid oligomer component recovered from a mixture after total reflux treatment or a mixture after total reflux treatment is charged.
- the mixture 302 can contain a solubilizer.
- the reaction vessel 301 While stirring the mixture 302, the reaction vessel 301 is heated under normal pressure or reduced pressure to depolymerize the glycolic acid oligomer in the solution phase, and from the depolymerization reaction system containing the mixture. Glycolide produced by polymerization is distilled (co-distilled) together with the high-boiling polar organic solvent. Each distillate reaches the pipe 304, the distillation column 305, the pipe 306, and the first heat exchanger 307, and is usually 70 to 180 ° C., preferably 75 to 150 ° C., more preferably by the first heat exchanger 307. Is cooled to a temperature in the range of 80-120 ° C.
- the first heat exchanger 307 and the distillation column 305 may be connected by a pipe 308 so that a part of the cooling material is returned to the distillation column 305.
- Each distillate that has passed through the first heat exchanger 307 is cooled by the second heat exchanger 310.
- the co-distillate cooled to the liquid state is stored in the separation tank 315 via the pipe 314.
- the depolymerization reaction is connected to the vacuum device 313 via the valve 311 and the pipe 312.
- the liquid co-distillate is phase-separated (layer separation) into an upper layer 316 made of a fraction containing a high-boiling polar organic solvent and a lower layer 317 made of a glycolide phase. Glycolide in the lower layer 317 is collected via the pipe 319 continuously or intermittently.
- the fraction of the upper layer 316 is returned to the depolymerization reaction system continuously or intermittently via the pipe 318. Instead of returning to the depolymerization reaction system, the fraction of the upper layer 316 can be discharged out of the system continuously or intermittently and reused.
- the amount of the mixture 302 in the depolymerization reaction system decreases as the glycolide is distilled out and recovered to the outside of the system, but the glycol recovered from the mixture after the total reflux treatment or the mixture after the total reflux treatment from the raw material input line 303
- the acid oligomer component is additionally charged into the depolymerization reaction system continuously or intermittently.
- a high boiling polar organic solvent can also be added. In this way, the depolymerization reaction can be carried out in a continuous operation.
- glycolide also referred to as crude glycolide
- the purity of glycolide (also referred to as crude glycolide) obtained by the production method of the present invention is preferably 99.0% or more, more preferably 99.3% or more, and still more preferably 99.3% from the initial stage of the depolymerization reaction. High purity of 5% or more. Therefore, the depolymerization reaction is carried out in a continuous operation while the glycolic acid oligomer component recovered from the mixture after the total reflux treatment or the mixture after the total reflux treatment is additionally charged into the depolymerization reaction system continuously or intermittently. Even so, high purity glycolide can be obtained.
- the measuring method is as follows.
- fusing point of glycolic acid oligomer is the value detected when it heats up at a speed
- Example 1 Using the apparatus shown in FIG. 1, 160 g of the oligomer obtained in Reference Example 1, 100 g of tetraethylene glycol dibutyl ether and 89 g of triethylene glycol monooctyl ether as a solubilizer were added to a 500 ml flask, and then up to 230 ° C. Heated the reaction system into a homogeneous solution. While this solution was heated to a temperature of 230 ° C., a total reflux treatment was performed for 3 hours under a reduced pressure of 4.5 kPa.
- the mixture after the total reflux treatment was heated to 230 ° C. to make the reaction system a uniform solution. While this solution was heated to a temperature of 230 ° C., tetraethylene glycol dibutyl ether and produced glycolide were co-distilled under a reduced pressure of 4.5 kPa. As a result of performing the depolymerization reaction for 1 hour, 9.3 g of glycolide was obtained. The purity of this glycolide was analyzed and found to be 99.6%.
- Example 2 Using the apparatus shown in FIG. 1, 160 g of the oligomer obtained in Reference Example 1, 100 g of diethylene glycol butyl 2-chlorophenyl ether and 95 g of diethylene glycol monodecyl ether as a solubilizing agent were added to a 500 ml flask and heated to 225 ° C. Thus, the reaction system was made into a uniform solution. While this solution was heated to a temperature of 225 ° C., a total reflux treatment was performed for 1 hour under a reduced pressure of 4.0 kPa.
- the mixture after the total reflux treatment was heated to 230 ° C. to make the reaction system a uniform solution. While this solution was heated to a temperature of 225 ° C., diethylene glycol butyl 2-chlorophenyl ether and glycolide produced were co-distilled under a reduced pressure of 4.0 kPa. As a result of performing the depolymerization reaction for 1 hour, 10.9 g of glycolide was obtained. The purity of this glycolide was analyzed and found to be 94.6%.
- Example 3 Using the apparatus shown in FIG. 1, 160 g of the oligomer obtained in Reference Example 1, 100 g of diethylene glycol dibutyl ether, and 84 g of diethylene glycol monodecyl ether as a solubilizer were added to a 500 ml flask, and then heated to 220 ° C. for reaction. The system was made into a homogeneous solution. While this solution was heated to a temperature of 225 ° C., a total reflux treatment was performed for 5 hours under a reduced pressure of 5.5 kPa.
- the mixture after the total reflux treatment was heated to 220 ° C. to make the reaction system a uniform solution. While heating this solution to a temperature of 225 ° C., diethylene glycol dibutyl ether and produced glycolide were co-distilled under a reduced pressure of 5.5 kPa. As a result of performing the depolymerization reaction for 1 hour, 9.2 g of glycolide was obtained. The purity of this glycolide was analyzed and found to be 99.0%.
- Example 4 Using the apparatus shown in FIG. 1, 160 g of the oligomer obtained in Reference Example 1, 100 g of triethylene glycol butyl decyl ether, and 100 g of polyethylene glycol monomethyl ether as a solubilizer were added to a 500 ml flask and heated to 235 ° C. Thus, the reaction system was made into a uniform solution. While this solution was heated to a temperature of 225 ° C., a total reflux treatment was performed for 2 hours under a reduced pressure of 2.5 kPa.
- the mixture after the total reflux treatment was heated to 220 ° C. to make the reaction system a uniform solution. While heating this solution to a temperature of 225 ° C., triethylene glycol butyl decyl ether and glycolide produced were co-distilled under a reduced pressure of 5.5 kPa. As a result of performing the depolymerization reaction for 1 hour, 10.5 g of glycolide was obtained. The purity of this glycolide was analyzed and found to be 99.1%.
- Example 5 Using the apparatus shown in FIG. 1, 160 g of the oligomer obtained in Reference Example 1, 100 g of triethylene glycol butyl hexyl ether, and 100 g of polyethylene glycol monohexyl ether as a solubilizer were added to a 500 ml flask up to 235 ° C. Heated the reaction system into a homogeneous solution. While this solution was heated to a temperature of 220 ° C., a total reflux treatment was performed for 2 hours under a reduced pressure of 3.5 kPa.
- the mixture after the total reflux treatment was heated to 220 ° C. to make the reaction system a uniform solution. While heating this solution to a temperature of 225 ° C., triethylene glycol butyl hexyl ether and produced glycolide were co-distilled under a reduced pressure of 3.5 kPa. As a result of performing the depolymerization reaction for 1 hour, 11.5 g of glycolide was obtained. The purity of this glycolide was analyzed and found to be 99.3%.
- Example 6 Using the apparatus shown in FIG. 1, 160 g of the oligomer obtained in Reference Example 1 and 100 g of tetraethylene glycol dibutyl ether were added to a 500 ml flask, and then heated to 230 ° C. to make the reaction system a uniform solution. While this solution was heated to a temperature of 230 ° C., a total reflux treatment was performed for 3 hours under a reduced pressure of 5.5 kPa.
- the mixture after the total reflux treatment was heated to 230 ° C. to make the reaction system a uniform solution. While heating this solution to a temperature of 230 ° C., tetraethylene glycol dibutyl ether and glycolide produced were co-distilled under a reduced pressure of 5.5 kPa. As a result of performing the depolymerization reaction for 1 hour, 11.0 g of glycolide was obtained. The purity of this glycolide was analyzed and found to be 96.3%.
- high-purity glycolide can be obtained from the initial stage of the depolymerization reaction. Therefore, according to the production method of the present invention, while the glycolic acid oligomer component recovered from the mixture after the total reflux treatment or the mixture after the total reflux treatment is added continuously or intermittently into the depolymerization reaction system, Even if the depolymerization reaction is carried out in a continuous operation, high-purity glycolide can be obtained.
- the production method of the present invention can be used for the production of high-purity glycolide.
- Glycolide obtained by the production method of the present invention can be used for the production of polyglycolic acid.
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Abstract
Description
(1)グリコール酸オリゴマー及び230~450℃の範囲内の沸点を持つ高沸点極性有機溶媒を含有する混合物を、常圧下または減圧下に加熱して還流させ、その際、該混合物を含有する還流系から留出する留出物の実質的に全量を該還流系内に還流させる条件下に、0.1~20時間の範囲内の還流時間で、全還流処理を行う工程1;
(2)全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分に該高沸点極性有機溶媒を加えた混合物を、常圧下または減圧下に、該グリコール酸オリゴマーが解重合する温度に加熱して、溶液相中で該グリコール酸オリゴマーの解重合を行うとともに、該混合物を含有する解重合反応系から解重合により生成したグリコリドを該高沸点極性有機溶媒と共に解重合反応系外に共留出させる工程2;並びに
(3)共留出物からグリコリドを取得する工程3;
の各工程を含むことを特徴とするグリコリドの製造方法が提供される。
グリコール酸オリゴマーは、重量平均分子量(Mw)が20,000以下、多くの場合10,000以下の低重合度(低分子量)のポリグリコール酸である。グリコール酸オリゴマーは、グリコール酸の重縮合によって合成することができる。グリコール酸は、そのエステル(例えば、低級アルキルエステル)や塩(例えば、ナトリウム塩)の形態であってもよい。
全還流処理工程及び解重合反応工程において、媒体として、高沸点極性有機溶媒を使用する。本発明では、230~450℃の範囲内の沸点を持つ高沸点極性有機溶媒を用いる。溶液相解重合法によりグリコール酸オリゴマーの解重合を行うには、溶媒として高沸点極性有機溶媒を使用することが、グリコール酸オリゴマーの溶液相を形成する上で必要である。高沸点極性有機溶媒は、解重合反応の溶媒として用いられるが、生成したグリコリドと共留出させて、グリコリドを解重合反応系外に随伴させる役割をも果す。高沸点極性有機溶媒をグリコリドと共留出させることにより、ライン内壁面にグリコリドが付着するのを防ぐことができる。
で表わされる、分子量150~450のポリアルキレングリコールジエーテルが好ましい。
本発明の製造方法では、全還流処理工程及び解重合反応工程において、高沸点極性有機溶媒を単独で使用することができるが、可溶化剤を併用することが好ましい。全還流処理工程で可溶化剤を使用すると、解重合により得られるグリコリドの純度が更に向上することが判明した。解重合反応工程で可溶化剤を使用すると、グリコール酸オリゴマーの溶液相状態での解重合が効率的に進行する。
で表わされる、250℃以上の沸点を持つポリアルキレングリコールモノエーテルが好ましい。
で表わされる、250℃以上の沸点を持つポリアルキレングリコールが好ましい。
本発明では、溶液相解重合法により、グリコール酸オリゴマー及び高沸点極性有機溶媒を含有する混合物を加熱して、グリコール酸オリゴマーの解重合を行うが、この解重合反応工程に先立って、該混合物の全還流処理を行う。
解重合反応工程では、全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分に高沸点極性有機溶媒を加えた混合物を、常圧下または減圧下に、グリコール酸オリゴマーが解重合する温度に加熱して、溶液相中でグリコール酸オリゴマーの解重合を行うとともに、該混合物を含有する解重合反応系から解重合により生成したグリコリドを高沸点極性有機溶媒と共に解重合反応系外に共留出させる。
解重合反応工程2において、解重合により生成したグリコリドを高沸点極性有機溶媒と共に解重合反応系外に共留出させ、共留出した共留出物からグリコリドを取得する。
本発明の製造方法は、前記工程1乃至3を、
a)該工程1で調製した全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分を、該工程2の解重合反応系内に連続的または間欠的に供給する工程a;
b)該工程2において、全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分に該高沸点極性有機溶媒を加えた混合物を、常圧下または減圧下に、該グリコール酸オリゴマーが解重合する温度に加熱して、溶液相中で該グリコール酸オリゴマーの解重合を連続的に行うとともに、該混合物を含有する解重合反応系から解重合により生成したグリコリドを該高沸点極性有機溶媒と共に解重合反応系外に連続的に共留出させる工程b;及び
c)該工程3において、該高沸点極性有機溶媒を含有する留分とグリコリドとの間の比重差を利用して、液状に冷却した共留出物の下層から連続的または間欠的にグリコリドを取得する工程c;
の各工程を組み合わせる方法により、連続運転で実施することができる。
本発明の製造方法により得られるグリコリド(粗グリコリドともいう)の純度は、解重合反応の初期段階から、好ましくは99.0%以上、より好ましくは99.3%以上、さらに好ましくは99.5%以上の高純度である。そのため、全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分を、連続的または間欠的に解重合反応系内に追加投入しながら、連続運転で解重合反応を実施しても、高純度のグリコリドを取得することができる。
グリコール酸オリゴマーの融点は、示差走査熱量計(DSC)を用いて、不活性ガス雰囲気下、10℃/分の速さで昇温加熱した際に検出される値である。
グリコリドの純度は、ガスクロマトグラフィー(GC)により4-クロロベンゾフェノンを内部標準として求めた値である。
グリコール酸70%水溶液工業用グレード(デュポン社製)1kgを1リットルのセパラブルフラスコへ仕込み、常圧で撹拌しながら室温から220℃まで4時間かけて昇温加熱し、生成水を留出させながら重縮合反応させた。次いで、缶内圧力を常圧から2kPaまで1時間かけてゆっくり減圧し、さらに3時間重縮合反応を続けて、未反応原料等の低沸点物を留去するとともに、グリコール酸オリゴマー480gを合成した。このグリコール酸オリゴマーの融点は、211℃であった。
図2に示す装置を用いて、500mlフラスコに、参考例1で得られたグリコール酸オリゴマー160g、テトラエチレングリコールジブチルエーテル100g、及び可溶化剤としてトリエチレングリコールモノオクチルエーテル89gを加えた後、230℃まで加熱して反応系を均一な溶液にした。この溶液を230℃の温度に加熱しながら、4.5kPaの減圧下に、テトラエチレングリコールジブチルエーテルと生成したグリコリドとを共留出させた。解重合反応を1時間継続した後、共留出物からグリコリド13gを取得した。このグリコリドの純度を分析したところ、93.4%であった。
図1に示す装置を用いて、500mlフラスコに、参考例1で得られたオリゴマー160g、テトラエチレングリコールジブチルエーテル100g、及び可溶化剤としてトリエチレングリコールモノオクチルエーテル89gを加えた後、230℃まで加熱して反応系を均一な溶液にした。この溶液を230℃の温度に加熱しながら、4.5kPaの減圧下に、3時間全還流処理を行った。
比較例1と実施例1との対比結果から明らかなように、本発明の製造方法によれば、解重合反応の初期段階から高純度のグリコリドを得ることができる。そのため、本発明の製造方法によれば、全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分を、連続的または間欠的に解重合反応系内に追加投入しながら、連続運転で解重合反応を実施しても、高純度のグリコリドを取得することができる。
図2に示す装置を用いて、500mlフラスコに、参考例1で得られたグリコール酸オリゴマー160g、ジエチレングリコールブチル2-クロロフェニルエーテル100g、及び可溶化剤としてジエチレングリコールモノデシルエーテル95gを加えた後、225℃まで加熱して反応系を均一な溶液にした。この溶液を225℃の温度に加熱しながら、4.0kPaの減圧下に、2-クロロフェニルエーテルと生成したグリコリドとを共留出させた。解重合反応を1時間継続した後、共留出物からグリコリド10.1gを取得した。このグリコリドの純度を分析したところ、89.0%であった。
図1に示す装置を用いて、500mlフラスコに、参考例1で得られたオリゴマー160g、ジエチレングリコールブチル2-クロロフェニルエーテル100g、及び可溶化剤としてジエチレングリコールモノデシルエーテル95gを加えた後、225℃まで加熱して反応系を均一な溶液にした。この溶液を225℃の温度に加熱しながら、4.0kPaの減圧下に、1時間全還流処理を行った。
比較例2と実施例2との対比結果から明らかなように、本発明の製造方法によれば、解重合反応の初期段階から高純度のグリコリドを得ることができる。
図2に示す装置を用いて、500mlフラスコに、参考例1で得られたグリコール酸オリゴマー160g、ジエチレングリコールジブチルエーテル100g、及び可溶化剤としてジエチレングリコールモノヘキシルエーテル84gを加えた後、220℃まで加熱して反応系を均一な溶液にした。この溶液を220℃の温度に加熱しながら、5.5kPaの減圧下に、ジエチレングリコールジブチルエーテルと生成したグリコリドを共留出させた。解重合反応を1時間継続した後、共留出物からグリコリド8.8gを取得した。このグリコリドの純度を分析したところ、88.2%であった。
図1に示す装置を用いて、500mlフラスコに、参考例1で得られたオリゴマー160g、ジエチレングリコールジブチルエーテル100g、及び可溶化剤としてジエチレングリコールモノデシルエーテル84gを加えた後、220℃まで加熱して反応系を均一な溶液にした。この溶液を225℃の温度に加熱しながら、5.5kPaの減圧下に、5時間全還流処理を行った。
比較例3と実施例3との対比結果から明らかなように、本発明の製造方法によれば、解重合反応の初期段階から高純度のグリコリドを得ることができる。
図2に示す装置を用いて、500mlフラスコに、参考例1で得られたグリコール酸オリゴマー160g、トリエチレングリコールブチルデシルエーテル100g、及び可溶化剤としてポリエチレングリコールモノメチルエーテル100gを加えた後、220℃まで加熱して反応系を均一な溶液にした。この溶液を235℃の温度に加熱しながら、2.5kPaの減圧下に、トリエチレングリコールブチルデシルエーテルと生成したグリコリドとを共留出させた。解重合反応を1時間継続した後、共留出物からグリコリド9.8gを取得した。このグリコリドの純度を分析したところ、90.2%であった。
図1に示す装置を用いて、500mlフラスコに、参考例1で得られたオリゴマー160g、トリエチレングリコールブチルデシルエーテル100g、及び可溶化剤としてポリエチレングリコールモノメチルエーテル100gを加えた後、235℃まで加熱して反応系を均一な溶液にした。この溶液を225℃の温度に加熱しながら、2.5kPaの減圧下に、2時間全還流処理を行った。
比較例4と実施例4との対比結果から明らかなように、本発明の製造方法によれば、解重合反応の初期段階から高純度のグリコリドを得ることができる。
図2に示す装置を用いて、500mlフラスコに、参考例1で得られたグリコール酸オリゴマー160g、トリエチレングリコールブチルヘキシルエーテル100g、及び可溶化剤としてポリエチレングリコールモノヘキシルエーテル100gを加えた後、220℃まで加熱して反応系を均一な溶液にした。この溶液を220℃の温度に加熱しながら、3.5kPaの減圧下に、トリエチレングリコールブチルデシルエーテルと生成したグリコリドとを共留出させた。解重合反応を1時間継続した後、共留出物からグリコリド10.8gを取得した。このグリコリドの純度を分析したところ、92.2%であった。
図1に示す装置を用いて、500mlフラスコに、参考例1で得られたオリゴマー160g、トリエチレングリコールブチルヘキシルエーテル100g、及び可溶化剤としてポリエチレングリコールモノヘキシルエーテル100gを加えた後、235℃まで加熱して反応系を均一な溶液にした。この溶液を220℃の温度に加熱しながら、3.5kPaの減圧下に、2時間全還流処理を行った。
比較例5と実施例5との対比結果から明らかなように、本発明の製造方法によれば、解重合反応の初期段階から高純度のグリコリドを得ることができる。
図2に示す装置を用いて、500mlフラスコに、参考例1で得られたグリコール酸オリゴマー160g、及びテトラエチレングリコールジブチルエーテル100gを加えた後、230℃まで加熱して反応系を均一な溶液にした。この溶液を230℃の温度に加熱しながら、5.5kPaの減圧下に、テトラエチレングリコールジブチルエーテルと生成したグリコリドとを共留出させた。解重合反応を1時間継続した後、共留出物からグリコリド9.8gを取得した。このグリコリドの純度を分析したところ、93.1%であった。
図1に示す装置を用いて、500mlフラスコに、参考例1で得られたオリゴマー160g、及びテトラエチレングリコールジブチルエーテル100gを加えた後、230℃まで加熱して反応系を均一な溶液にした。この溶液を230℃の温度に加熱しながら、5.5kPaの減圧下に、3時間全還流処理を行った。
比較例6と実施例6との対比結果から明らかなように、本発明の製造方法によれば、解重合反応の初期段階から高純度のグリコリドを得ることができる。
5 加熱手段
8 還流冷却管
10 第一冷却トラップ
14 第二冷却トラップ
16 真空装置
21 反応容器
25 加熱手段
28 第一熱交換器
29 分離槽
31 第二熱交換器
33 第一冷却トラップ
37 第二冷却トラップ
39 真空装置
42 容器
301 反応槽
302 混合物
303 原料投入配管
305 蒸留塔
307 第一熱交換器
310 第二熱交換器
313 真空装置
315 分離槽
316 溶媒相(上層)
317 グリコリド相(下層)
318 溶媒戻し配管
319 グリコリド回収配管
Claims (15)
- グリコール酸オリゴマー及び高沸点極性有機溶媒を含有する混合物の加熱により、溶液相中で該グリコール酸オリゴマーを解重合させる工程を含むグリコリドの製造方法において、
(1)グリコール酸オリゴマー及び230~450℃の範囲内の沸点を持つ高沸点極性有機溶媒を含有する混合物を、常圧下または減圧下に加熱して還流させ、その際、該混合物を含有する還流系から留出する留出物の実質的に全量を該還流系内に還流させる条件下に、0.1~20時間の範囲内の還流時間で、全還流処理を行う工程1;
(2)全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分に該高沸点極性有機溶媒を加えた混合物を、常圧下または減圧下に、該グリコール酸オリゴマーが解重合する温度に加熱して、溶液相中で該グリコール酸オリゴマーの解重合を行うとともに、該混合物を含有する解重合反応系から解重合により生成したグリコリドを該高沸点極性有機溶媒と共に解重合反応系外に共留出させる工程2;並びに
(3)共留出物からグリコリドを取得する工程3;
の各工程を含むことを特徴とするグリコリドの製造方法。 - 該グリコール酸オリゴマーが、重量平均分子量20,000以下の低分子量ポリグリコール酸である請求項1記載の製造方法。
- 該工程1で使用する混合物が、該グリコール酸オリゴマー及び該高沸点極性有機溶媒に加えて、可溶化剤として、それぞれ180℃以上の沸点を持つ一価アルコール類、多価アルコール類、フェノール類、一価脂肪族カルボン酸類、多価脂肪族カルボン酸類、脂肪族アミド類、脂肪族イミド類、分子量が450超過のポリアルキレングリコールジエーテル、及びスルホン酸類からなる群より選ばれる少なくとも一種の非塩基性有機化合物を更に含有する混合物である請求項1記載の製造方法。
- 該工程1で使用する混合物が、該可溶化剤を、グリコール酸オリゴマー/可溶化剤のモル比が1~99の範囲内となる量比で含有する混合物である請求項4記載の製造方法。
- 該工程2において、該全還流処理後の混合物から回収したグリコール酸オリゴマー成分に高沸点極性有機溶媒を加えた混合物を使用する場合、該混合物が、可溶化剤として、それぞれ180℃以上の沸点を持つ一価アルコール類、多価アルコール類、フェノール類、一価脂肪族カルボン酸類、多価脂肪族カルボン酸類、脂肪族アミド類、脂肪族イミド類、分子量が450超過のポリアルキレングリコールジエーテル、及びスルホン酸類からなる群より選ばれる少なくとも一種の非塩基性有機化合物を更に含有する混合物である請求項1記載の製造方法。
- 該工程2において、該全還流処理後の混合物から回収したグリコール酸オリゴマー成分に高沸点極性有機溶媒を加えた混合物を使用する場合、該混合物が、該可溶化剤を、グリコール酸オリゴマー/可溶化剤のモル比が1~99の範囲内となる量比で含有する混合物である請求項8記載の製造方法。
- 該工程1において、該混合物を、1~30kPaの減圧下に加熱して、全還流処理を行う請求項1記載の製造方法。
- 前記工程1乃至3を、
a)該工程1で調製した全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分を、該工程2の解重合反応系内に連続的または間欠的に供給する工程a;
b)該工程2において、全還流処理後の混合物または全還流処理後の混合物から回収したグリコール酸オリゴマー成分に該高沸点極性有機溶媒を加えた混合物を、常圧下または減圧下に、該グリコール酸オリゴマーが解重合する温度に加熱して、溶液相中で該グリコール酸オリゴマーの解重合を連続的に行うとともに、該混合物を含有する解重合反応系から解重合により生成したグリコリドを該高沸点極性有機溶媒と共に解重合反応系外に連続的に共留出させる工程b;及び
c)該工程3において、該高沸点極性有機溶媒を含有する留分とグリコリドとの間の比重差を利用して、液状に冷却した共留出物の下層から連続的または間欠的にグリコリドを取得する工程c;
の各工程を組み合わせる方法により、連続運転で実施する請求項1記載の製造方法。 - 該工程cにおいて、液状に冷却した共留出物の下層から連続的または間欠的にグリコリドを取得するとともに、該共留出物の上層の高沸点極性有機溶媒を含有する留分を連続的または間欠的に排出する請求項13記載の製造方法。
- 該工程cにおいて、液状に冷却した共留出物の下層から連続的または間欠的にグリコリドを取得するとともに、該共留出物の上層の高沸点極性有機溶媒を含有する留分を連続的または間欠的に解重合反応系内に戻す請求項13記載の製造方法。
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US20040231845A1 (en) | 2003-05-15 | 2004-11-25 | Cooke Claude E. | Applications of degradable polymers in wells |
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Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH05287056A (ja) * | 1992-04-07 | 1993-11-02 | Toyobo Co Ltd | 脂肪族ポリエステルの製造方法 |
JPH07138253A (ja) * | 1993-11-17 | 1995-05-30 | Shimadzu Corp | ラクチドの製造法 |
JPH09328481A (ja) | 1996-02-09 | 1997-12-22 | Kureha Chem Ind Co Ltd | α−ヒドロキシカルボン酸2量体環状エステルの製造方法及び精製方法 |
WO2002014303A1 (fr) | 2000-08-11 | 2002-02-21 | Kureha Kagaku Kogyo K.K. | Procede de preparation d'esters cycliques et procede de purification desdits esters |
JP2002114775A (ja) * | 2000-10-12 | 2002-04-16 | Kureha Chem Ind Co Ltd | グリコリドの製造方法 |
JP2004523596A (ja) | 2001-04-12 | 2004-08-05 | 呉羽化学工業株式会社 | グリコリドの製造方法及びグリコリド製造用グリコール酸オリゴマー |
JP2007332113A (ja) * | 2006-06-19 | 2007-12-27 | Kureha Corp | グリコリドの製造方法およびグリコリド製造用グリコール酸オリゴマー |
JP2008001733A (ja) * | 2006-06-20 | 2008-01-10 | Hitachi Ltd | ポリヒドロキシカルボン酸の合成法及び合成装置 |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5830991A (en) * | 1996-02-09 | 1998-11-03 | Kureha Kagaku Kagyo Kk | Preparation process and purification process of dimeric cyclic ester of hydroxycarboxylic acid |
-
2009
- 2009-12-09 EP EP09834327.0A patent/EP2377858B1/en not_active Not-in-force
- 2009-12-09 JP JP2010543795A patent/JP5584628B2/ja active Active
- 2009-12-09 US US13/142,012 patent/US8722907B2/en active Active
- 2009-12-09 WO PCT/JP2009/006713 patent/WO2010073512A1/ja active Application Filing
- 2009-12-18 TW TW098143667A patent/TW201035116A/zh unknown
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH05287056A (ja) * | 1992-04-07 | 1993-11-02 | Toyobo Co Ltd | 脂肪族ポリエステルの製造方法 |
JPH07138253A (ja) * | 1993-11-17 | 1995-05-30 | Shimadzu Corp | ラクチドの製造法 |
JPH09328481A (ja) | 1996-02-09 | 1997-12-22 | Kureha Chem Ind Co Ltd | α−ヒドロキシカルボン酸2量体環状エステルの製造方法及び精製方法 |
WO2002014303A1 (fr) | 2000-08-11 | 2002-02-21 | Kureha Kagaku Kogyo K.K. | Procede de preparation d'esters cycliques et procede de purification desdits esters |
JP2002114775A (ja) * | 2000-10-12 | 2002-04-16 | Kureha Chem Ind Co Ltd | グリコリドの製造方法 |
JP2004523596A (ja) | 2001-04-12 | 2004-08-05 | 呉羽化学工業株式会社 | グリコリドの製造方法及びグリコリド製造用グリコール酸オリゴマー |
JP2007332113A (ja) * | 2006-06-19 | 2007-12-27 | Kureha Corp | グリコリドの製造方法およびグリコリド製造用グリコール酸オリゴマー |
JP2008001733A (ja) * | 2006-06-20 | 2008-01-10 | Hitachi Ltd | ポリヒドロキシカルボン酸の合成法及び合成装置 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2377858A4 |
Cited By (13)
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US8722908B2 (en) | 2010-01-19 | 2014-05-13 | Kureha Corporation | Method for producing glycolide |
WO2011089802A1 (ja) * | 2010-01-19 | 2011-07-28 | 株式会社クレハ | グリコリドの製造方法 |
JPWO2014080876A1 (ja) * | 2012-11-22 | 2017-01-05 | 株式会社クレハ | 気液の向流接触による精留工程を備えるグリコリドの製造方法、及び、粗グリコリドの精製方法 |
WO2014080876A1 (ja) * | 2012-11-22 | 2014-05-30 | 株式会社クレハ | 気液の向流接触による精留工程を備えるグリコリドの製造方法、及び、粗グリコリドの精製方法 |
US9365536B2 (en) | 2012-11-22 | 2016-06-14 | Kureha Corporation | Method for producing glycolide, which is provided with rectification step by means of gas-liquid countercurrent contact, and method for purifying crude glycolide |
WO2014157140A1 (ja) | 2013-03-26 | 2014-10-02 | 株式会社クレハ | グリコリドの製造方法 |
US9512100B2 (en) | 2013-03-26 | 2016-12-06 | Kureha Corporation | Method for producing glycolide |
JPWO2014157140A1 (ja) * | 2013-03-26 | 2017-02-16 | 株式会社クレハ | グリコリドの製造方法 |
KR101729877B1 (ko) | 2013-03-26 | 2017-04-24 | 가부시끼가이샤 구레하 | 글리콜리드의 제조방법 |
JPWO2014156809A1 (ja) * | 2013-03-27 | 2017-02-16 | 株式会社クレハ | グリコリドの製造方法 |
KR101741936B1 (ko) | 2013-03-27 | 2017-05-30 | 가부시끼가이샤 구레하 | 글리콜라이드의 제조 방법 |
WO2019172361A1 (ja) | 2018-03-07 | 2019-09-12 | 株式会社クレハ | 環状エステルの製造方法 |
US11078179B2 (en) | 2018-03-07 | 2021-08-03 | Kureha Corporation | Method for producing cyclic ester |
Also Published As
Publication number | Publication date |
---|---|
TW201035116A (en) | 2010-10-01 |
US20110263875A1 (en) | 2011-10-27 |
EP2377858B1 (en) | 2014-04-30 |
EP2377858A1 (en) | 2011-10-19 |
US8722907B2 (en) | 2014-05-13 |
EP2377858A4 (en) | 2012-06-27 |
JP5584628B2 (ja) | 2014-09-03 |
JPWO2010073512A1 (ja) | 2012-06-07 |
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