JP2013057072A - Polymer product, molding, medical molding, toner and polymer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that, in the method for ring-opening polymerizing a ring-opening polymerizable monomer by using a compressible fluid such as supercritical carbon dioxide, when using as the catalyst an organic catalyst not containing metal atoms, high molecular weight polymer products are not obtained even prolonging the reaction over long hours, which results in the degradation of durability and softening point of the polymer product under the influence of low molecular weight components.SOLUTION: This polymer product does not substantially contain an organic solvent and a metal catalyst, the amount of residual ring-opening polymerizable monomer is 1,000 ppm or less, and the number-average molecular weight is 15,000 or more. Thereby an advantage is achieved that lowering of durability or softening point under the influence of low molecular weight components can be controlled.

Description

  The present invention relates to polymer products.

  Conventionally, various polymers have been produced by ring-opening polymerization of ring-opening polymerizable monomers. For example, polylactic acid is produced by ring-opening polymerization of lactide as an example of a ring-opening polymerizable monomer. The produced polylactic acid is utilized as a suture fiber, a biocompatible material sheet, cosmetic particles, a plastic bag film, or the like.

  As a method for producing a polymer by ring-opening polymerization of a ring-opening polymerizable monomer, a method of reacting the ring-opening polymerizable monomer in a molten state is known. For example, as a method for producing polylactic acid by ring-opening polymerization of lactide, a method is known in which tin octylate is used as a catalyst and reaction temperature is set to 195 ° C. to react and polymerize lactide in a molten state ( Patent Document 1). However, when polylactic acid is produced by this production method, more than 2% of lactide remains in the product (see Patent Document 1). This is because in a ring-opening polymerization reaction system such as lactide, an equilibrium relationship between the ring-opening polymerizable monomer and the polymer is established, and the ring-opening polymerizable monomer is subjected to ring-opening polymerization at a high temperature such as the above reaction temperature. This is because a ring-opening polymerizable monomer is easily generated by a depolymerization reaction. The remaining lactide (ring-opening polymerizable monomer) functions as a hydrolysis catalyst for the product or reduces heat resistance. In this case, it is known that lactide is reduced under reduced pressure in a molten state of polylactic acid (see Patent Document 2), but coloring may occur by keeping the polylactic acid in a molten state. Moreover, although it is known that a hydrolysis inhibitor is used (see Patent Document 3), the addition of the hydrolysis inhibitor may reduce the molding processability and may deteriorate the physical properties of the resulting molded article.

  As a method for ring-opening polymerization of a ring-opening polymerizable monomer at a low reaction temperature, a method of ring-opening polymerization of lactide in an organic solvent is disclosed (see Patent Document 4). According to the disclosed method, poly-D-lactic acid is obtained at a monomer conversion of 99.4% by polymerizing D-lactide in dichloromethane solution at 25 ° C. However, when the polymerization is carried out using an organic solvent, not only the treatment for drying the organic solvent is required when the polymer is used, but the organic solvent remains in the product even if this treatment is carried out. there is a possibility.

  As a method for ring-opening polymerization of a ring-opening polymerizable monomer without using an organic solvent, a method of ring-opening polymerization of L-lactide using a metal catalyst in supercritical carbon dioxide has been disclosed (Non-patent Document). 1). According to the disclosed method, tin octylate is used as the metal catalyst, the reaction temperature is 80 ° C., the pressure is 207 bar, and 10 w / v% l-lactide with respect to supercritical carbon dioxide is polymerized for 47 hours, Obtained fine particles of polylactic acid. However, when polylactic acid is produced by this production method, there is a problem that tin octylate, which is a metal catalyst, remains in the product. This is because the catalyst contains metal atoms and is not easily removed from the product. The remaining tin octylate reduces the heat resistance and safety of the product.

  In a method for ring-opening polymerization of lactide using supercritical carbon dioxide, a method using an organic catalyst containing no metal atom as a catalyst is disclosed (see Non-Patent Document 2). According to the disclosed method, lactide and 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) as an organic catalyst are charged into an autoclave, and then stirred and carbon dioxide is added. The lactide is polymerized by a procedure of 250 atm. In this method, a polymer having a number average molecular weight of about 10,000 is obtained by reacting for 16 hours (see Non-Patent Document 2).

  However, in the method of ring-opening polymerization of a ring-opening polymerizable monomer using a compressive fluid such as supercritical carbon dioxide, when an organic catalyst containing no metal atom is used as a catalyst, the reaction is continued for a long time. However, a polymer product having a high molecular weight was not obtained. For this reason, the subject that durability and softening temperature of a polymer product fall by the influence of a low molecular-weight component arises.

  The invention according to claim 1 is a polymer product characterized by being substantially free of an organic solvent and a metal catalyst, having a residual ring-opening polymerizable monomer amount of 1000 ppm or less, and a number average molecular weight of 15000 or more. is there.

  As described above, the polymer product of the present invention substantially does not contain an organic solvent and a metal catalyst, has a residual ring-opening polymerizable monomer amount of 1000 ppm or less, and a number average molecular weight of 15000 or more. Thereby, there exists an effect that it can suppress that durability and softening temperature of a polymer product fall by the influence of a low molecular-weight component.

It is a general phase diagram showing the state of a substance with respect to temperature and pressure. It is a phase diagram for defining the range of compressive fluid in this embodiment. It is a systematic diagram showing an example of a continuous polymerization process. It is a systematic diagram showing an example of a batch type polymerization process. It is a systematic diagram showing an example of a batch type polymerization process.

  Hereinafter, an embodiment of the present invention will be described. The polymer product of this embodiment is obtained by ring-opening polymerization of a ring-opening polymerizable monomer using a compressive fluid and an organic catalyst not containing a metal atom.

<< Raw materials >>
First, raw materials such as a ring-opening polymerizable monomer and an organic catalyst used for producing the above polymer will be described. In the present embodiment, the raw material is a material from which a polymer is produced, and is a material that is a constituent component of the polymer.

<Organic catalyst>
The organic catalyst used in the present embodiment does not contain a metal atom in order to ensure the safety and stability of the product. In this embodiment, the organic catalyst contributes to the ring-opening polymerization reaction of the ring-opening polymerizable monomer, forms an active intermediate with the ring-opening polymerizable monomer, and then desorbs and regenerates by reaction with the alcohol. I just need it.

  As the organic catalyst, for example, when polymerizing a ring-opening polymerizable monomer having an ester bond, a compound that functions as a basic nucleophile (nucleophilic) is preferable, a compound containing a nitrogen atom is more preferable, and nitrogen More preferred are cyclic compounds containing atoms. The compound as described above is not particularly limited, but a cyclic monoamine, a cyclic diamine (a cyclic diamine compound having an amidine skeleton), a cyclic triamine compound having a guanidine skeleton, a heterocyclic aromatic organic compound containing a nitrogen atom, N -Heterocyclic carbene and the like. A cationic organic catalyst is used in the above ring-opening polymerization reaction. In this case, since hydrogen is extracted from the polymer main chain (back-biting), the molecular weight distribution is widened to obtain a high molecular weight product. Hateful.

  An example of a cyclic amine is quinuclidine. Examples of cyclic diamines include 1,4-diazabicyclo- [2.2.2] octane (DABCO) and 1,5-diazabicyclo (4,3,0) -5-nonene. Examples of the cyclic diamine compound having an amidine skeleton include 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) and diazabicyclononene. Examples of cyclic triamine compounds having a guanidine skeleton include 1,5,7-triazabicyclo [4.4.0] dec-5-ene (TBD) and diphenylguanidine (DPG).

  Examples of heterocyclic aromatic organic compounds containing a nitrogen atom include N, N-dimethyl-4-aminopyridine (DMAP), 4-pyrrolidinopyridine (PPY), pyrocholine, imidazole, pyrimidine, and purine. . Examples of N-heterocyclic carbene include 1,3-di-tert-butylimidazol-2-ylidene (ITBU). Among these, DABCO, DBU, DPG, TBD, DMAP, PPY, and ITBU are preferable because they are less affected by steric hindrance and have high nucleophilicity or have a boiling point that can be removed under reduced pressure.

  Among these organic catalysts, for example, DBU is liquid at room temperature and has a boiling point. When such an organic catalyst is selected, the organic catalyst can be almost quantitatively removed from the polymer by subjecting the obtained polymer to a reduced pressure treatment. In addition, the kind of organic catalyst and the presence or absence of a removal process are determined according to the use purpose of a product, etc.

  The type and amount of the organic catalyst vary depending on the combination of the compressive fluid and the ring-opening polymerizable monomer described later, and thus cannot be generally specified. The mol% or less is preferable, 0.1 mol% or more and 1 mol% or less is more preferable, and 0.3 mol% or more and 0.5 mol% or less is more preferable. When the amount used is less than 0.01 mol%, the organic catalyst may be deactivated before the polymerization reaction is completed, and a polymer having a target molecular weight may not be obtained. On the other hand, when the amount used exceeds 15 mol%, it may be difficult to control the polymerization reaction.

<Ring-opening polymerizable monomer>
The ring-opening polymerizable monomer used in this embodiment preferably has an ester bond in the ring. Examples of such ring-opening polymerizable monomers include cyclic esters and cyclic carbonates.

Although it does not specifically limit as cyclic ester, The cyclic dimer obtained by dehydrating and condensing at least one of the L-form or D-form of the compound represented by following General formula (1) is used suitably.
R—C * —H (—OH) (— COOH) General formula (1)
(In general formula (1), R represents an alkyl group having 1 to 10 carbon atoms. In general formula (1), “*” represents an asymmetric carbon.)

  Specific examples of the compound represented by the general formula (1) include an enantiomer of lactic acid, an enantiomer of 2-hydroxybutanoic acid, an enantiomer of 2-hydroxypentanoic acid, and an enantiomer of 2-hydroxyhexanoic acid. , 2-hydroxyheptanoic acid enantiomer, 2-hydroxyoctanoic acid enantiomer, 2-hydroxynonanoic acid enantiomer, 2-hydroxydecanoic acid enantiomer, 2-hydroxyundecanoic acid enantiomer And enantiomers of 2-hydroxydodecanoic acid. Among these, the enantiomer of lactic acid is particularly preferable from the viewpoint of reactivity or availability. These cyclic dimers can be used alone or in admixture of several kinds.

  Examples of cyclic esters other than the general formula (1) include β-propiolactone, β-butyrolactone, γ-butyrolactone, γ-hexanolactone, γ-octanolactone, δ-valerolactone, and δ-hexalanolactone. , Δ-octanolactone, ε-caprolactone, δ-dodecanolactone, α-methyl-γ-butyrolactone, β-methyl-δ-valerolactone, glycolide, lactide, and the like. In particular, ε-caprolactone is preferable from the viewpoint of reactivity and availability.

  Examples of the cyclic carbonate include, but are not limited to, ethylene carbonate and propylene carbonate. These ring-opening polymerizable monomers may be used alone or in combination of two or more.

<Initiator>
In the present embodiment, a ring-opening polymerization initiator (initiator) can be used to control the molecular weight of the obtained polymer. As the initiator, known ones can be used, and any alcoholic mono-, di- or polyhydric alcohols may be used, and either saturated or unsaturated may be used. Specific examples of the initiator include monoalcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, nonanol, decanol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol; ethylene glycol, 1,2 -Dialcohols such as propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexanediol, nonanediol, tetramethylene glycol, polyethylene glycol; glycerol, sorbitol, xylitol, ribitol, And polyhydric alcohols such as erythritol and triethanolamine; and methyl lactate and ethyl lactate.

  Further, a polymer having an alcohol residue at the terminal, such as polycaprolactone diol or polytetramethylene glycol, can be used as an initiator. Thereby, a diblock copolymer, a triblock copolymer, etc. are synthesize | combined.

  What is necessary is just to adjust suitably the usage-amount of an initiator according to the target molecular weight, Preferably it is 0.1 mol% or more and 5 mol% or less with respect to 100 mol% of ring-opening polymerizable monomers. In order to prevent the polymerization from starting inhomogeneously, it is desirable to mix the monomer and the initiator in advance before the monomer contacts the polymerization catalyst.

<Additives>
In the ring-opening polymerization, an additive may be added as necessary. Examples of additives include surfactants, antioxidants, stabilizers, ultraviolet absorbers, pigments, colorants, inorganic particles, various fillers, mold release agents, plasticizers, and the like. If necessary, a polymerization terminator (benzoic acid, hydrochloric acid, phosphoric acid, metaphosphoric acid, acetic acid, lactic acid, etc.) can be used after the polymerization reaction.

  As the surfactant, those that are soluble in a compressive fluid described later and that have affinity for both the compressive fluid and the ring-opening polymerizable monomer are suitably used. By using such a surfactant, the polymerization reaction can be progressed uniformly, the molecular weight distribution of the product becomes narrow, and effects such as easy to obtain a particulate polymer can be expected. When the surfactant is allowed to coexist in the polymerization system, it may be added to the compressive fluid or to the ring-opening polymerizable monomer.

<< Compressive fluid >>
Next, a compressive fluid used for producing a polymer in the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a phase diagram showing the state of a substance with respect to temperature and pressure. FIG. 2 is a phase diagram for defining the range of the compressible fluid in the present embodiment. In the present embodiment, the “compressible fluid” means that a substance exists in any of the regions (1), (2), and (3) shown in FIG. 2 in the phase diagram shown in FIG. It means the state of time.

  In such a region, it is known that the substance has a very high density and behaves differently from that at normal temperature and pressure. In addition, when a substance exists in the area | region of (1), it becomes a supercritical fluid. A supercritical fluid is a fluid that exists as a non-condensable high-density fluid in a temperature and pressure region that exceeds the limit (critical point) at which gas and liquid can coexist, and does not condense even when compressed. Further, when the substance is present in the region (2), it becomes a liquid, but in this embodiment, it is obtained by compressing a substance that is in a gaseous state at normal temperature (25 ° C.) and normal pressure (1 atm). Represents liquefied gas. Further, when the substance is present in the region (3), it is in a gaseous state, but in the present embodiment, it represents a high pressure gas whose pressure is 1/2 (1/2 Pc) or more of the critical pressure (Pc).

  Examples of substances that can be used in the state of a compressive fluid include carbon monoxide, carbon dioxide, dinitrogen monoxide, nitrogen, methane, ethane, propane, 2,3-dimethylbutane, and ethylene. Among these, carbon dioxide is preferable in that it has a critical pressure of about 7.4 MPa and a critical temperature of about 31 ° C., can easily create a supercritical state, and is nonflammable and easy to handle. These compressive fluids may be used alone or in combination of two or more.

  Conventionally, when supercritical carbon dioxide is used as a solvent, carbon dioxide is considered to react with a substance having basicity and nucleophilicity, and thus cannot be applied to living anion polymerization (Non-patent Document 3). reference). However, the present inventors overturned the conventional knowledge, and even in supercritical carbon dioxide, a stable basic and nucleophilic organic catalyst is coordinated to a ring-opening monomer and quantified. It was found that the polymerization reaction proceeded and the polymerization reaction proceeded in a living manner. “Living” here means that the reaction proceeds quantitatively without side reactions such as transfer reaction and termination reaction, and the molecular weight distribution of the obtained polymer is narrow and monodispersed.

<< Polymerization reactor >>
Subsequently, a polymerization reaction apparatus used for polymer production in the present embodiment will be described with reference to FIGS. 3 and 4. 3 and 4 are system diagrams showing an example of the polymerization process. First, the polymerization reaction apparatus 100 will be described with reference to FIG. The polymerization reaction apparatus 100 includes a supply unit 100a that supplies raw materials such as a ring-opening polymerizable monomer and a compressive fluid, and a polymerization reaction as an example of a continuous polymerization apparatus that polymerizes the ring-opening polymerizable monomer supplied by the supply unit 100a. And an apparatus main body 100b. The supply unit 100a has a tank (1, 3, 5, 7, 11), a measuring feeder (2, 4), and a measuring pump (6, 8, 12). The polymerization reaction device main body 100b is connected to the mixing device 9, the liquid feed pump 10, the reaction vessel 13, the metering pump 14, and the other end of the polymerization reaction device main body 100b provided at one end of the polymerization reaction device main body 100b. And an extrusion die 15 provided. In this embodiment, an apparatus that mixes a compressive fluid and raw materials or polymers to dissolve or plasticize the raw materials and the like is referred to as a “mixing apparatus”.

  The tank 1 of the supply unit 100a stores a ring-opening polymerizable monomer. The ring-opening polymerizable monomer to be stored may be a powder or a molten state. The tank 3 stores solid (powder or granular) of the initiator and the additive. The tank 5 stores a liquid one of the initiator and the additive. The tank 7 stores a compressible fluid. The tank 7 may store a gas (gas) or a solid that becomes a compressible fluid in the course of being supplied to the mixing device 9 or heated or pressurized in the mixing device 9. In this case, the gas or solid stored in the tank 7 is heated or pressurized to be in the state (1), (2), or (3) in the phase diagram of FIG. .

  The metering feeder 2 measures the ring-opening polymerizable monomer stored in the tank 1 and continuously supplies it to the mixing device 9. The weighing feeder 4 measures the solid stored in the tank 3 and continuously supplies it to the mixing device 9. The metering pump 6 measures the liquid stored in the tank 5 and continuously supplies it to the mixing device 9. The metering pump 8 continuously supplies the compressive fluid stored in the tank 7 to the mixing device 9 at a constant pressure and flow rate. In addition, in this embodiment, supplying continuously is a concept with respect to the method of supplying for every batch, and means supplying so that the polymer which carried out ring-opening polymerization may be obtained continuously. That is, each material may be supplied intermittently or intermittently as long as the ring-opened polymer is continuously obtained. In addition, when both the initiator and the additive are solid, the polymerization reaction apparatus 100 may not include the tank 5 and the metering pump 6. Similarly, when both the initiator and the additive are liquid, the polymerization reaction apparatus 100 may not include the tank 3 and the metering feeder 4.

  In this embodiment, each apparatus of the polymerization reaction apparatus main body 100b is connected as shown in FIG. 3 by a pressure-resistant piping 30 that transports raw materials, a compressive fluid, or a generated polymer. Moreover, each apparatus of the mixing apparatus 9 of the polymerization reaction apparatus, the liquid feeding pump 10, and the reaction vessel 13 has a tubular member through which the above raw materials and the like pass.

  The mixing device 9 of the polymerization reaction device main body 100b includes raw materials such as ring-opening polymerizable monomers, initiators and additives supplied from the tanks (1, 3, 5), and a compressive fluid supplied from the tank 7. Is a device having a pressure-resistant container for continuously contacting and melting raw materials. In this embodiment, since the raw material such as the ring-opening polymerizable monomer and the compressive fluid can be continuously contacted at a constant concentration ratio, the raw material can be efficiently dissolved or plasticized. . In this embodiment, the state in which the raw material and the compressive fluid are dissolved or plasticized by bringing them into contact with each other includes the state in which the raw material such as the ring-opening polymerizable monomer is dissolved in the compressive fluid and the state in which the raw material is compressed. It includes the state of being plasticized and liquefied while being swollen by coming into contact with the ionic fluid.

  The shape of the container of the mixing device 9 may be a tank type or a cylindrical shape, but a cylindrical shape in which raw materials are supplied from one end and the mixture is taken out from the other end is preferable. In the container of the mixing device 9, an inlet 9 a for introducing the compressive fluid supplied from the tank 7 by the metering pump 8 and an inlet 9 b for introducing the ring-opening polymerizable monomer supplied from the tank 1 by the metering feeder 2 are introduced. In addition, an introduction port 9 c for introducing the powder supplied from the tank 3 by the measuring feeder 4 and an introduction port 9 d for introducing the liquid supplied from the tank 5 by the measuring pump 6 are provided. In this embodiment, each introduction port (9a, 9b, 9c, 9d) is comprised by the coupling which connects the container of the mixing apparatus 9, and each piping which conveys each raw material or compressive fluid. This joint is not particularly limited, and known joints such as reducers, couplings, Y, T, and outlets are used. Moreover, the mixing apparatus 9 has a heater for heating each supplied raw material and compressive fluid. Furthermore, the mixing device 9 may have a stirring device that stirs the raw materials, the compressive fluid, and the like. When the mixing device 9 has a stirrer, the stirrer includes a uniaxial screw, a biaxial screw meshing with each other, a biaxial mixer having a large number of meshing elements meshing with each other or overlapping each other, and a helical stirring element meshing with each other. A kneader having a static mixer, a static mixer or the like is preferably used. In particular, a biaxial or multiaxial agitation device that meshes with each other is preferable because there is little adhesion of reactants to the agitation device or the container and there is a self-cleaning action.

  In the case where the mixing device 9 does not have a stirring device, a pressure-resistant pipe is preferably used as the mixing device 9. In this case, it is possible to reduce the installation space of the polymerization reaction apparatus 100 or improve the layout flexibility by arranging the pressure-resistant piping in a spiral shape or by bending it. In addition, when the mixing apparatus 9 does not have a stirring apparatus, in order to mix each material in the mixing apparatus 9 reliably, it is preferable that the ring-opening polymerizable monomer supplied to the mixing apparatus 9 is in a molten state. .

  The liquid feed pump 10 sends each raw material dissolved or plasticized by the mixing device 9 to the reaction vessel 13. The tank 11 stores the organic catalyst. The metering pump 12 measures the organic catalyst stored in the tank 11 and supplies it to the reaction vessel 13.

  The reaction vessel 13 mixes each dissolved or plasticized raw material fed by the liquid feed pump 10 and the organic catalyst supplied by the metering pump 12 to continuously open the ring-opening polymerizable monomer. A pressure-resistant container for polymerization. The shape of the reaction vessel 13 may be a tank type or a cylindrical type, but a cylindrical type with little dead space is preferable. The reaction vessel 13 has an introduction port 13a for introducing each material mixed by the mixing device 9 into the vessel, and an introduction port 13b for introducing the organic catalyst supplied from the tank 11 by the metering pump 12 into the vessel. Is provided. In this embodiment, each inlet (13a, 13b) is comprised by the coupling which connects the reaction container 13 and each piping which conveys each raw material. This joint is not particularly limited, and known joints such as reducers, couplings, Y, T, and outlets are used. Note that the reaction vessel 13 may be provided with a gas outlet for removing evaporated substances. The reaction vessel 13 has a heater for heating the fed raw material. Furthermore, the reaction vessel 13 may have a stirring device that stirs the raw materials, the compressive fluid, and the like. When the reaction vessel 13 has a stirrer, the polymer can be prevented from settling due to the difference in density between the raw material and the produced polymer, so that the polymerization reaction can proceed more uniformly and quantitatively. As a stirring device for the reaction vessel 13, a twin shaft having a screw which meshes with each other, a stirring element such as a 2-flight (oval) or a 3-flight (triangular shape), a disc or a multi-leaf type (clover-shaped) stirring blade. Or the thing of a multi-axis is preferable from a viewpoint of self-cleaning. When the raw material containing the catalyst is sufficiently mixed in advance, a static mixer that performs multi-stage splitting and combining (merging) of the flow with a guide device can also be applied to the stirring device. As static mixers, those disclosed in JP-B-47-15526, 47-15527, 47-15528, 47-15533, etc. (multilayer mixer), and disclosed in JP-A-47-33166. And the like (Kenix type) and similar mixing devices without moving parts.

  When the reaction vessel 13 does not have a stirrer, pressure-resistant piping is preferably used as the reaction vessel 13. In this case, it is possible to reduce the installation space of the polymerization reaction apparatus 100 or improve the layout flexibility by arranging the pressure-resistant piping in a spiral shape or by bending it.

  Although FIG. 3 shows an example in which one reaction vessel 13 is provided, two or more reaction vessels 13 may be used. When a plurality of reaction vessels 13 are used, the reaction (polymerization) conditions for each reaction vessel 13, that is, temperature, catalyst concentration, pressure, average residence time, stirring speed, etc. may be the same. It is preferable to select the optimum conditions. In order to increase the reaction time and complicate the apparatus, it is not a good idea to combine too many containers in multiple stages, and the number of stages is preferably 1 or more and 4 or less, particularly preferably 1 or more and 3 or less.

  In general, when polymerization is performed with only one reaction vessel, the degree of polymerization of the polymer obtained and the amount of residual monomer are unstable and easily fluctuate, and are not suitable for industrial production. This is considered to be caused by instability due to mixing of a polymerization raw material having a melt viscosity of several poise to several tens of poise and a polymerized polymer having a melt viscosity of about 1,000 poise in the same container. . On the other hand, in this embodiment, since the raw material and the generated polymer are dissolved or plasticized in the compressive fluid, it is possible to reduce the difference in viscosity in the system, so that the number of stages is higher than that of the conventional polymerization reaction apparatus. It becomes possible to reduce.

  The metering pump 14 sends the polymer product P in the reaction vessel 13 out of the reaction vessel 13 from an extrusion die 15 as an example of a polymer discharge port. In addition, the polymer product P can be sent out from the reaction vessel 13 without using the metering pump 14 by utilizing the pressure difference between the inside and outside of the reaction vessel 13. In this case, in order to adjust the pressure in the reaction vessel 13 and the delivery amount of the polymer product P, a pressure adjusting valve can be used instead of the metering pump 14.

  Next, the polymerization reaction apparatus 200 used in the batch process will be described. In the system diagram of FIG. 4, the polymerization reaction device 200 includes a tank 21, a metering pump 22, an addition pot 25, a reaction vessel 27, and valves (23, 24, 26, 28, 29). . Each of the above devices is connected as shown in FIG. Further, the pipe 30 is provided with joints (30a, 30b).

  The tank 21 stores a compressible fluid. The tank 21 may store a gas (gas) or a solid that becomes a compressible fluid by being heated and pressurized in a supply path supplied to the reaction container 27 or in the reaction container 27. In this case, the gas or solid stored in the tank 21 is heated or pressurized to be in the state (1), (2), or (3) in the phase diagram of FIG. .

  The metering pump 22 supplies the compressive fluid stored in the tank 21 to the reaction vessel 27 at a constant pressure and flow rate. The addition pot 25 stores an organic catalyst added to the raw material in the reaction vessel 27. The valves (23, 24, 26, 29) open and close each of them, thereby supplying the compressive fluid stored in the tank 21 to the reaction vessel 27 via the addition pot 25 and the addition pot 25. The route for supplying the reaction vessel 27 without going through is switched.

  The reaction vessel 27 contains a ring-opening polymerizable monomer and an initiator in advance before starting the polymerization. The reaction vessel 27 is prepared by bringing the ring-opening polymerizable monomer and initiator stored in advance, the compressive fluid supplied from the tank 21 and the organic catalyst supplied from the addition pot 25 into contact with each other. Is a pressure-resistant container for ring-opening polymerization. The reaction vessel 27 may be provided with a gas outlet for removing the evaporated material. The reaction vessel 27 has a heater for heating the raw materials and the compressive fluid. Furthermore, the reaction vessel 27 has a stirring device for stirring the raw materials and the compressive fluid. When the density difference between the raw material and the generated polymer occurs, the settling of the generated polymer can be suppressed by adding the stirring of the stirring device, so that the polymerization reaction can proceed more uniformly and quantitatively. The valve 28 is opened after completion of the polymerization reaction to discharge the polymer product P in the reaction vessel 27.

<< Polymerization method >>
Then, the polymerization method of the ring-opening polymerizable monomer using the polymerization reaction apparatus 100 as an example of the polymerization reaction apparatus will be described. First, each metering feeder (2, 4), metering pump 6 and metering pump 8 are operated, and lactide as a ring-opening polymerizable monomer in each tank (1, 3, 5, 7), initiator, additive, The compressive fluid is continuously introduced into the container of the mixing device 9 from each inlet (9a, 9b, 9c, 9d). In addition, solid (powder or granular) raw materials may have lower measurement accuracy than liquid raw materials. In this case, the solid raw material may be melted in advance and stored in the tank 5 in a liquid state and introduced into the container of the mixing device 9 by the metering pump 6. The order in which each metering feeder (2, 4), metering pump 6 and metering pump 8 are operated is not particularly limited, but when the initial raw material is sent to the reaction vessel 13 without contacting the compressed fluid, it solidifies due to a decrease in temperature. Therefore, it is preferable to operate the metering pump 8 first.

  Since each raw material and compressive fluid are continuously introduced into the container of the mixing device 9, they are in continuous contact with each other. Thereby, in the mixing apparatus 9, each raw material, such as a ring-opening polymerizable monomer, an initiator, and an additive, is dissolved or plasticized. When the mixing device 9 has a stirring device, the raw materials and the compressive fluid may be stirred. In order to prevent the introduced compressive fluid from turning into a gas, the temperature and pressure in the container of the reaction vessel 13 are controlled to a temperature and pressure at least above the triple point of the compressive fluid. This control is performed by adjusting the output of the heater of the mixing device 9 or the supply amount of the compressive fluid. In this embodiment, the temperature at which the ring-opening polymerizable monomer is dissolved or plasticized may be a temperature not higher than the melting point of the ring-opening polymerizable monomer at normal pressure. This is considered to be due to the high pressure in the mixing device 9 in the presence of the compressive fluid, and the melting point of the ring-opening polymerizable monomer being lower than the melting point at normal pressure. For this reason, even when the amount of the compressive fluid relative to the ring-opening polymerizable monomer is small, the ring-opening polymerizable monomer is dissolved or plasticized in the mixing device 9.

  The timing at which heat or agitation is applied to each raw material and compressive fluid by the mixing device 9 may be adjusted so that each raw material is efficiently dissolved or plasticized. In this case, heat or agitation may be applied after contacting each raw material and the compressive fluid, or heat or agitation may be applied while contacting each raw material and the compressive fluid. In order to dissolve or plasticize more reliably, for example, the ring-opening polymerizable monomer and the compressive fluid may be brought into contact with each other after the ring-opening polymerizable monomer is previously melted by applying heat equal to or higher than the melting point. For example, when the mixing device 9 is a biaxial mixing device, each of the above-described aspects is appropriately set by adjusting the screw arrangement, the arrangement of the inlets (9a, 9b, 9c, 9d), and the temperature of the heater of the mixing device 9. This is realized by setting.

  In this embodiment, the additive is supplied to the mixing device 9 separately from the ring-opening polymerizable monomer, but the additive may be supplied together with the ring-opening polymerizable monomer. Further, an additive may be supplied after the polymerization reaction. In this case, after taking out the polymer product P obtained from the reaction vessel 13, the additive can be added while melt-kneading.

  Each raw material dissolved or plasticized by the mixing device 9 is fed by the liquid feed pump 10 and supplied to the reaction vessel 13 from the inlet 13a. On the other hand, the organic catalyst in the tank 11 is measured by the metering pump 12 and supplied to the reaction vessel 13 through the introduction port 13b. Since the organic catalyst can act at room temperature, in this embodiment, the organic catalyst is added after the raw material is dissolved or plasticized by avoiding supplying the organic catalyst to the mixing device 9. Conventionally, in a method for ring-opening polymerization of a ring-opening polymerizable monomer using a compressive fluid, the timing for adding a catalyst has not been studied. In this embodiment, in the ring-opening polymerization, the organic catalyst is a reaction vessel in which a mixture of raw materials such as a ring-opening polymerizable monomer and an initiator is sufficiently dissolved or plasticized by a compressive fluid because of its high activity. 13 is added to the polymerization system. When an organic catalyst is added in a state where the mixture is not sufficiently dissolved or plasticized, the reaction proceeds non-uniformly and a difference in viscosity occurs in the reaction system, which may make it difficult to increase the molecular weight of the product polymer. is there.

  Each material fed by the liquid feed pump 10 and the organic catalyst supplied by the metering pump 12 are sufficiently stirred by the stirring device of the reaction vessel 13 as necessary, and heated to a predetermined temperature by the heater. Thereby, the ring-opening polymerizable monomer is subjected to ring-opening polymerization in the presence of the organic catalyst in the reaction vessel 13 (polymerization step).

  The lower limit of the temperature (polymerization reaction temperature) for ring-opening polymerization of the ring-opening polymerizable monomer is not particularly limited, but is 40 ° C, preferably 50 ° C, more preferably 60 ° C. When the polymerization reaction temperature is less than 40 ° C., depending on the ring-opening polymerizable monomer species, it takes a long time to dissolve by the compressive fluid, the dissolution is insufficient, or the activity of the organic catalyst is lowered. As a result, the reaction rate tends to decrease during polymerization, and the polymerization reaction may not proceed quantitatively.

  The upper limit of the polymerization reaction temperature is not particularly limited, but is 100 ° C. or 30 ° C. higher than the melting point of the ring-opening polymerizable monomer, whichever is higher. The upper limit of the polymerization reaction temperature is preferably 90 ° C. or the higher of the melting points of the ring-opening polymerizable monomers. The upper limit of the polymerization reaction temperature is more preferably 80 ° C. or a temperature lower by 20 ° C. than the melting point of the ring-opening polymerizable monomer. When the polymerization reaction temperature exceeds 30 ° C. higher than the melting point of the ring-opening polymerizable monomer, the depolymerization reaction, which is the reverse reaction of the ring-opening polymerization, tends to occur in equilibrium, and the polymerization reaction is difficult to proceed quantitatively. When using a ring-opening monomer having a low melting point, such as a ring-opening polymerizable monomer that is liquid at room temperature, the polymerization reaction temperature may be 30 ° C. higher than the melting point in order to increase the activity of the organic catalyst. Even in this case, the polymerization reaction temperature is preferably 100 ° C. or lower. The polymerization reaction temperature is controlled by a heater provided in the reaction vessel 13 or heating from the outside of the reaction vessel 13.

  In this embodiment, the polymerization reaction time (average residence time in the reaction vessel 13) is set according to the target molecular weight, but when the number average molecular weight is 15000 or more, it depends on other conditions. However, the polymerization reaction time is usually from 10 minutes to 6 hours.

  The pressure at the time of polymerization, that is, the pressure of the compressive fluid is such that the compressive fluid supplied from the tank 7 is a liquefied gas ((2) in the phase diagram of FIG. 2) or a high-pressure gas ((3) in the phase diagram of FIG. 2). The pressure that becomes the supercritical fluid ((1) in the phase diagram of FIG. 2) is preferable. By making the compressible fluid into a supercritical fluid state, dissolution or plasticization of the ring-opening polymerizable monomer is promoted, and the polymerization reaction can proceed uniformly and quantitatively. When carbon dioxide is used as a compressive fluid, the pressure is 3.7 MPa or more, preferably 5 MPa or more, more preferably 7.4 PMa or more of the critical pressure, considering the efficiency of the reaction and the polymer conversion rate. is there. Moreover, when using a carbon dioxide as a compressive fluid, it is preferable that the temperature is 25 degreeC or more for the same reason. In the present embodiment, the concentration of the compressive fluid is not particularly limited as long as it is a concentration capable of dissolving or plasticizing the ring-opening polymerizable monomer and the polymer generated from the ring-opening polymerizable monomer in the compressive fluid. .

  The amount of water in the reaction vessel 13 is 4 mol% or less, more preferably 1 mol% or less, still more preferably 0.5 mol% or less, relative to 100 mol% of the ring-opening polymerizable monomer. When the amount of water exceeds 4 mol%, the water itself contributes as an initiator, so that it may be difficult to control the molecular weight. In order to control the amount of water in the polymerization reaction system, an operation for removing water contained in the ring-opening polymerizable monomer and other raw materials may be added as a pretreatment as necessary.

  The polymer product P that has finished the ring-opening polymerization reaction in the reaction vessel 13 is sent out of the reaction vessel 13 by the metering pump 14. The rate at which the metering pump 14 delivers the polymer product P is preferably constant in order to obtain a uniform polymerized product by operating at a constant pressure in the polymerization system filled with the compressive fluid. Therefore, the liquid feeding mechanism inside the reaction vessel 13 and the liquid feeding amount of the liquid feeding pump 10 are controlled so that the back pressure of the metering pump 14 is constant. Similarly, the feeding speed of the liquid feeding mechanism, the measuring feeders (2, 4), and the measuring pumps (6, 8) in the mixing device 9 are controlled so that the back pressure of the liquid feeding pump 10 is constant. The control method may be an ON-OFF type, that is, an intermittent feed type, but a continuous or step method in which the rotational speed of a pump or the like is gradually increased or decreased is often more preferable. In any case, a uniform polymer product can be stably obtained by such control.

  The organic catalyst remaining in the polymer product obtained by this embodiment is removed as necessary. Thereby, the residual amount of the organic catalyst in a polymer product can be 2 wt%. The method for removing the organic catalyst is not particularly limited. For example, if the compound has a boiling point, it is distilled under reduced pressure, or the organic catalyst is extracted using a substance that dissolves the organic catalyst as an entrainer. Examples thereof include a removal method and a method in which an organic catalyst is adsorbed and removed by a column. In this case, the method for removing the organic catalyst may be a batch method in which the polymer product is removed after being taken out from the reaction vessel, or a method in which the organic catalyst is continuously treated without being taken out. In the case of distilling off under reduced pressure, the reduced pressure condition is set based on the boiling point of the organic catalyst. For example, the temperature during decompression is 100 ° C. or more and 120 ° C. or less, and the organic catalyst can be removed at a temperature lower than the temperature at which the polymer is depolymerized. When an organic solvent is used in this extraction operation, a step of removing the organic solvent after extracting the organic catalyst may be required. For this reason, it is preferable to use a compressed fluid as a solvent also in extraction operation. As such an extraction operation, a known technique such as extraction of a fragrance can be diverted.

(Application examples)
In the production method of this embodiment, since the reaction proceeds quantitatively with almost no residual monomer, a copolymer having two or more polymer segments can be obtained by appropriately setting the timing for adding several types of ring-opening polymerizable monomers. It is also possible to synthesize or to produce a mixture of polymers. Hereinafter, two methods for producing a stereocomplex are shown as an example of a copolymer or a mixture.

  In the first method, a ring-opening polymerizable monomer (for example, L-lactide) is polymerized in the reaction vessel 13, and after the reaction is quantitatively terminated, another optical isomer ring-opening polymerizable monomer (for example, D -Lactide) is added, and the polymerization reaction is further carried out in the reaction vessel 13. Thereby, a stereocomplex (stereoblock copolymer) is obtained. This method is very useful because the reaction can proceed at a temperature lower than the melting point of the ring-opening polymerizable monomer in the form of a small amount of residual monomers, and racemization is very unlikely and can be obtained in a one-step reaction.

  In the second method, an L-form polymer and a D-form polymer (for example, polylactic acid) are polymerized in advance in the compressive fluid in the polymerization reactor 100. Further, these polymerized polymers are mixed in a compressive fluid to obtain a stereocomplex. In general, polymers such as polylactic acid often decompose when heated and dissolved again, even when the residual monomer is extremely small. The second method is useful because low-viscosity polylactic acid dissolved or plasticized with a compressive fluid can be blended at a melting point or lower to suppress racemization and thermal degradation as in the first method. It is.

<< Polymer product >>
According to the manufacturing method of the present embodiment, by using a compressive fluid, as described above, a polymerization reaction at a low temperature is possible, so that the depolymerization reaction can be significantly suppressed as compared with the conventional melt polymerization. . Thereby, the residual monomer amount contained in the polymer product can be specifically set to 1000 ppm or less, preferably 300 ppm or less, more preferably 100 ppm or less. When the residual monomer amount exceeds 1000 ppm, the heat stability is deteriorated due to a decrease in thermal characteristics, and in addition, the carboxylic acid generated when the residual monomer is ring-opened has a catalytic function to promote hydrolysis. Decomposition tends to proceed. In addition, if the monomer has volatility, when processing the polymer product depending on the application, such as fiber, film, and molded product, the problem of contamination of the die and mold, resulting in a decrease in production efficiency In addition, the quality of the product itself may be impaired. Therefore, the stability of the polymer product obtained by this embodiment is greatly improved with respect to the above characteristics. In addition, according to this embodiment, a polymer product having a residual ring-opening polymerizable monomer amount of 1000 ppm or less can be obtained by appropriately selecting each of the above polymerization reaction conditions without performing a separate removal treatment.

  The number average molecular weight of the polymer obtained by this embodiment is 15000 or more, and can be appropriately adjusted according to the application. When the number average molecular weight is less than 15000, the polymer becomes brittle, so use in applications may be limited. The value obtained by dividing the weight average molecular weight of the polymer obtained by the present embodiment by the number average molecular weight is preferably 1.2 or more and 2.5 or less, more preferably 1.2 or more and 2.0 or less, and particularly preferably. Is 1.2 or more and 1.5 or less. When this value is larger than 2.5, the low molecular weight component increases and the decomposability may become too high.

  Since the polymer product obtained by the present embodiment is produced by a production method that does not use a metal catalyst and an organic solvent, it is substantially free of a metal catalyst and an organic solvent, and the amount of residual monomer is also extremely low at 1000 ppm or less. Excellent safety and stability. Therefore, the particles according to the present embodiment are widely applied as applications such as daily necessities, pharmaceuticals, cosmetics, and electrophotographic toners. In this embodiment, the metal catalyst is a catalyst used for ring-opening polymerization and contains a metal. When the content of the metal catalyst in the polymer product is detected by a known analytical method such as ICP emission spectrometry, atomic absorption spectrometry, or colorimetry, for example, the detection limit is substantially not included. Say the following. In the present embodiment, the organic solvent is an organic solvent used for ring-opening polymerization. The phrase “substantially free of organic solvent” means that the content of the organic solvent in the polymer product measured by the following measurement method is below the detection limit.

(Measurement method of residual organic solvent)
After adding 2 parts by mass of 2-propanol to 1 part by mass of the polymer product to be measured and dispersing with ultrasonic waves for 30 minutes, it is stored in a refrigerator (5 ° C.) for 1 day or longer, and the organic solvent in the polymer product To extract. The supernatant is analyzed by gas chromatography (GC-14A, SHIMADZU), and the organic solvent concentration is measured by quantifying the organic solvent and residual monomers in the polymer product. Measurement conditions at the time of such analysis are as follows.
Equipment: Shimadzu GC-14A
Column: CBP20-M 50-0.25
Detector: FID
Injection volume: 1-5 μl
Carrier gas: He 2.5kg / cm2
Hydrogen flow rate: 0.6 kg / cm2
Air flow rate: 0.5 kg / cm2
Chart speed: 5mm / min
Sensitivity: Range101 × Atten20
Column temperature: 40 ° C
Injection Temp: 150 ° C

  The polymer product produced by the above production method has a small amount of residual monomer and has a very low reaction temperature, and therefore, mainly discoloration such as yellowing is suppressed and becomes white. The product being white means that a YI value measured by using a SM color computer (manufactured by Suga Test Instruments Co., Ltd.) in accordance with JIS-K7103 after preparing a 2 mm thick resin pellet. means.

<< Molded Article >>
Subsequently, molded articles such as particles, films, sheets, molded articles, fibers, and foams obtained by molding the polymer product produced by the above production method will be described.

<Particle>
Examples of the method for forming the polymer product obtained by the above production method into particles include a method of pulverizing the polymer product by a conventionally known method. The particle size of the particles is not particularly limited, but is usually 1 μm or more and 50 μm or less. Further, when the particles of the molded body are electrophotographic toners, a mixture in which a colorant and hydrophobic fine particles are mixed in a polymer product is prepared. The mixture may contain other additives in addition to the binder resin, the colorant, and the hydrophobic fine particles. Examples of other additives include release agents and charge control agents. The step of mixing the additive may be performed at the same time as the polymerization reaction, or may be added while melting and kneading after the polymerization reaction or after taking out the polymerization product.

<Film>
In the present embodiment, a film is a polymer component formed into a thin film and has a thickness of less than 250 μm. In this embodiment, the film is produced by stretching and molding the polymer product obtained by the production method described above.

  In this case, the stretch molding method is not particularly limited, but a uniaxial stretch molding method applied to general-purpose plastic stretch molding, a simultaneous or sequential biaxial stretch molding method (tubular method, tenter method, etc.), etc. should be adopted. Can do.

  Film forming is usually performed in a temperature range of 150 ° C to 280 ° C. The formed film is uniaxially or biaxially stretched by a roll method, a tenter method, a tubular method or the like. The stretching temperature is usually in the range of 30 ° C to 110 ° C, preferably 50 ° C to 100 ° C. The draw ratio is usually in the range of 0.6 to 10 times in the vertical and horizontal directions, respectively. Moreover, after extending | stretching, you may perform heat processing, such as the method of spraying a hot air, the method of irradiating infrared rays, the method of irradiating a microwave, and making it contact on a heat roll.

  By such a stretch molding method, various stretched films such as a stretched sheet, a flat yarn, a stretched tape or band, a striped tape, and a split yarn can be obtained. The thickness of the stretched film is arbitrary depending on the application, but is usually 5 μm or more and less than 250 μm.

  The formed stretched film has chemical functions, electrical functions, magnetic functions, mechanical functions, friction / wear / lubrication functions, optical functions, thermal functions, surface functions such as biocompatibility, etc. Various purposeful secondary processing can be performed for the purpose of application. Examples of secondary processing include embossing, painting, adhesion, printing, metalizing (plating, etc.), machining, surface treatment (antistatic treatment, corona discharge treatment, plasma treatment, photochromism treatment, physical vapor deposition, chemical vapor deposition, Coating, etc.).

  The stretched film obtained according to the present embodiment uses a polymer product produced by a production method that does not use a metal catalyst and an organic solvent, does not contain a metal catalyst and an organic solvent, and the amount of residual monomer is extremely low at 1000 ppm or less. Therefore, it is excellent in safety and stability. Therefore, the stretched film of the present embodiment is widely applied as uses such as daily necessities, packaging materials, pharmaceuticals, electrical equipment materials, home appliance housings, automobile materials and the like. When the resulting polymer product is a biodegradable polymer such as polylactic acid or polycaprolactone, taking advantage of the fact that it does not contain solvents or metals, it can be used in applications that may enter the body, especially food. It becomes useful as medical materials such as packaging materials, cosmetics, and pharmaceuticals to be used.

<Sheets and molded products>
In the present embodiment, the sheet is a sheet in which a polymer component is formed into a thin film and has a thickness of 250 μm or more. In the present embodiment, the sheet is produced by applying a conventionally known sheet production method used for thermoplastic resins to the polymer product obtained by the above production method. Such a method is not particularly limited, and examples thereof include a T-die method, an inflation method, and a calendar method. The processing conditions for processing into a sheet are appropriately determined based on the type of polymer product, the apparatus, and the like. For example, when polylactic acid is processed by the T-die method, the temperature is preferably adjusted by extruding a polymer product heated to 150 ° C. or more and 250 ° C. or less from the T die by an extruder with the T die attached to the outlet. Can be processed into a sheet.

  In the present embodiment, the molded product is a product processed using a mold. The concept of the molded product includes not only a molded product as a single unit but also a product including a molded product such as a tray handle or a molded product such as a tray to which a handle is attached.

  The processing method is not particularly limited, but can be processed by a conventionally known thermoplastic resin method, and examples thereof include injection molding, vacuum molding, pressure molding, vacuum pressure molding, press molding, and the like. In this case, the polymer product obtained by the above production method can be melted and injection molded to obtain a molded product. Moreover, a molded article can also be obtained by press-molding the sheet obtained by the above production method using a molding die and imparting a shape (giving a shape). The processing conditions at the time of shaping are appropriately determined based on the type of polymer product, the apparatus, and the like. For example, when the polylactic acid sheet of this embodiment is molded by press molding using a molding die, the mold temperature can be set to 100 ° C. or higher and 150 ° C. or lower. When molding by injection molding, a polymer product heated to 150 ° C. or more and 250 ° C. or less is injected into a mold, the mold temperature is set to about 20 ° C. or more and 80 ° C. or less, and injection molding is performed. Processing is possible.

  Conventionally, the polylactic acid resin used for general purposes has a large residual ratio of metal catalyst, organic solvent, and monomer. When such polylactic acid is heated to form a sheet, for example, the remaining foreign matter such as metal catalyst, organic solvent, and monomer may become fish-eye and the appearance may be impaired or the strength may be reduced. was there. In addition, when such polylactic acid is used for molding by molding or injection molding, the appearance may be similarly impaired or the strength may be lowered.

  On the other hand, the sheet and the molded product according to the present embodiment use a polymer product manufactured by a manufacturing method that does not use a metal catalyst and an organic solvent, do not include the metal catalyst and the organic solvent, and have a residual monomer amount. Is extremely low, 1000 ppm or less. Thereby, the sheet | seat and molded product obtained by this embodiment are excellent in safety | security, stability, and an external appearance. Therefore, the sheet and the molded product of the present embodiment are not particularly limited, but are widely used as industrial materials, daily necessities, agricultural products, food products, pharmaceutical products, cosmetics sheets, packaging materials, trays and the like. Here, when the obtained polymer product is a polymer having biodegradability such as polylactic acid or polycaprolactone, it is possible to enter the body by taking advantage of the fact that it does not contain a solvent or metal. In particular, it is useful as a packaging material used for food, cosmetics, and medical sheets such as pharmaceuticals.

<Fiber>
The polymer product obtained by the above production method can also be applied to fibers such as monofilaments and multifilaments. In this embodiment, the concept of fibers includes not only single fibers such as monofilaments, but also intermediate products composed of fibers such as woven fabrics and nonwoven fabrics, and woven fabrics and nonwoven fabrics such as masks. Product included.

  In this embodiment, in the case of a monofilament, the fiber is produced by converting the polymer product obtained by the above production method into a fiber by melt spinning, cooling and stretching by a conventionally known method. Depending on the application, a coating layer may be formed on the monofilament by a conventionally known method, and the coating layer may contain an antibacterial agent, a colorant and the like. In the case of a non-woven fabric, a method of melt spinning, cooling, stretching, opening, deposition, and heat treatment by a conventionally known method can be used. The polymer product may contain additives such as an antioxidant, a flame retardant, an ultraviolet absorber, an antistatic agent, an antibacterial agent, and a binder resin. The step of mixing the additive may be performed at the time of the polymerization reaction, or may be added while melting and kneading after the post-polymerization reaction or after taking out the polymerization product.

  The fiber obtained by this embodiment uses a polymer product produced by a production method that does not use a metal catalyst and an organic solvent, does not contain a metal catalyst and an organic solvent, and the amount of residual monomer is extremely low, 1000 ppm or less. Therefore, it is excellent in safety and stability. Therefore, if the fiber of this embodiment is a monofilament, it is widely applied as uses, such as a fishing line, a fish net, a surgical suture, a medical material, an electric equipment material, an automobile material, an industrial material. Moreover, if the fiber of this embodiment is a nonwoven fabric, it will be widely applied for uses such as fishery / agricultural materials, construction / civil engineering materials, interiors, automobile members, packaging materials, daily goods, and sanitary materials.

<Foam>
The foam according to this embodiment is obtained by foaming the polymer product produced by the above production method. The concept of the foam includes not only a foam as a simple substance such as a foam resin but also a part having a foam such as a heat insulating material and a soundproofing agent, and a product having a foam such as a building material.

As an efficient method for producing a foamed product, the polymer product in a state of being dissolved or plasticized in a compressible fluid is heated and depressurized, and vaporization of the compressive fluid in the polymer product is used to reduce the foam. The method of obtaining is mentioned. It is believed that the compressed fluid in the polymer product diffuses at a rate of 10 ⁻⁵ to 10 ⁻⁶ / sec when released to the atmosphere. When the pressure is released, since the enthalpy is constant, a temperature drop may occur, and it may be difficult to control the cooling rate. Even in this case, when the elasticity of the polymer when released to the atmosphere is large, bubbles are maintained and a foam is formed.

  In order to obtain a foam molded product, a predetermined amount of a polymer product dissolved or plasticized in a compressible fluid is directly injected into a molding die, the pressure is reduced, and then the foam molded product is molded by heat molding. Mold. Examples of the heating means include steam, conduction heat, radiant heat, and microwaves. In this case, it is preferable to perform foam molding by heating to about 100 to 140 ° C. with these heating means, and preferably heating to 110 to 125 ° C. with steam.

  Moreover, a foam can also be manufactured by applying the manufacturing method of a general foamable plastic to the polymer product manufactured by said manufacturing method. In this case, the strand which extruded the resin composition which mix | blended desired additives, such as a modifier and a nucleating agent, with said polymer product was obtained using the general melt extruder. Next, pellets or particles are obtained from the obtained strands using a pelletizer (particle formation step). These particles or pellets are put into an autoclave and put into a gas phase or a liquid phase such as water or pure water, and any conventional use such as a dispersant, anti-fusing agent, anti-tacking agent, etc. Using this additive, a resin particle dispersion is prepared. Furthermore, foamed particles are obtained by foaming the resin particle dispersion using a volatile foaming agent (foaming step). The particles are exposed to the atmosphere, air is permeated into the particle bubbles, and moisture attached to the particles is removed as necessary (aging process). Then, the foamed particles are filled in a closed mold having small holes and slits, and heated and foamed to form a molded body in which the individual particles are fused and integrated.

  The foam obtained by the present embodiment uses a polymer product produced by a production method that does not use a metal catalyst and an organic solvent, does not contain a metal catalyst and an organic solvent, and has a very low residual monomer amount of 1000 ppm or less. Therefore, it is excellent in safety and stability. Therefore, the foam according to the present embodiment is widely applied as a buffer material, a heat insulating material, a soundproof material, a vibration control material, or the like.

<< Polymer composition >>
Then, the polymer composition containing the polymer product manufactured by said manufacturing method is demonstrated. In the present embodiment, the polymer composition means a substance containing a polymer product. The polymer composition is not limited in form as long as it contains a polymer product. For example, even if the polymer composition is a solid containing the polymer product and an additive, it is a liquid in which the polymer product is dissolved in a solvent. Alternatively, a dispersion in which a polymer product is dispersed in a dispersion medium may be used. The polymer composition obtained by the present embodiment uses a polymer product produced by a production method that does not use a metal catalyst and an organic solvent, does not contain a metal catalyst and an organic solvent, and the residual monomer amount is extremely low at 1000 ppm or less. Because it is few, it is excellent in safety and stability. Therefore, the polymer composition of the present embodiment is widely applied as uses for daily necessities, packaging materials, pharmaceuticals, electrical equipment materials, home appliance housings, automobile materials, and the like. When the polymer composition contains a biodegradable polymer product such as polylactic acid or polycaprolactone, it is possible to enter the body by taking advantage of the fact that it does not contain solvent or metal, especially food. It is useful as a medical material such as packaging materials, cosmetics, and pharmaceuticals used in packaging.

<< Effects of Embodiment >>
The polymer product of this embodiment is obtained by ring-opening polymerization of a ring-opening polymerizable monomer using a compressible fluid and an organic catalyst not containing a metal atom, and the amount of residual ring-opening polymerizable monomer is 1000 ppm or less. Yes, the number average molecular weight is 15000 or more. This polymer product can be produced without using an organic solvent, and since the amount of residual ring-opening polymerizable monomer and the amount of low molecular weight components are small, it is possible to suppress a decrease in the safety and stability of particles due to these components. There is an effect. Moreover, there exists an effect that it can suppress that durability and softening temperature of a molded object fall under the influence of the low molecular-weight component in a polymer product.

  Hereinafter, the present embodiment will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples.

  The physical properties of the polymer products obtained in the examples and comparative examples were determined as follows.

<Molecular weight of polymer>
Measurement was performed by GPC (Gel Permeation Chromatography) under the following conditions.
-Equipment: GPC-8020 (manufactured by Tosoh Corporation)
Column: TSK G2000HXL and G4000HXL (manufactured by Tosoh Corporation)
・ Temperature: 40 ℃
・ Solvent: Chloroform ・ Flow rate: 1.0 mL / min Inject 1 mL of a sample with a concentration of 0.5% by weight, and use a molecular weight calibration curve created by a monodisperse polystyrene standard sample from the molecular weight distribution of the polymer measured under the above conditions. The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the toner were calculated. The molecular weight distribution is a value obtained by dividing Mw by Mn.

<Glass transition temperature (Tg)>
Device: DSC (TA Instruments, Q2000)
What filled 5-10 mg of samples in the aluminum simple airtight bread | pan was used for the following measurement flows.
1st heating: 30 ° C. to 220 ° C., 5 ° C./min. 1 minute after reaching 220 ° C
Cooling: Quench to −20 ° C. without temperature control, hold for 1 minute after reaching −20 ° C. Second heating: −20 ° C. to 180 ° C., 5 ° C./min.
The glass transition temperature was evaluated by adopting the midpoint method in the second heating thermogram and reading the value.

<Softening point>
Apparatus: Flow tester (manufactured by Shimadzu Corporation, CFT-500D)
Sample: 1.5g,
Temperature increase rate: 10 ° C / min,
Load: 10kg,
Nozzle: Diameter 0.5mm, length 1mm
Heating start temperature: 50 ° C.
Preheating time: 300 seconds,
1/2 method: The temperature at which half of the sample flowed out was taken as the softening point.

<Residual monomer amount (mol%) = Unreacted monomer amount (mol%)>
The amount of residual monomer in the polymer product (polylactic acid) is described in “Voluntary Standards for Food Containers and Packaging Made of Synthetic Resins such as Polyolefins, Third Edition Revised Edition, June 2004 Supplement, Part 3, Sanitation Test Law, P13” It can be determined according to the method for measuring the amount of lactide. Specifically, a polymer product such as polylactic acid is uniformly dissolved in dichloromethane, and the supernatant obtained by reprecipitation of the polymer product by adding an acetone / cyclohexane mixed solution is gas chromatograph with a hydrogen flame detector (FID). The residual monomer amount in the polymer product can be measured by subjecting it to (GC) and separating the residual monomer (lactide) and quantifying it by an internal standard method. The GC measurement can be performed under the following conditions.

(GC measurement conditions)
Column: Capillary column <Example> DB-17MS manufactured by J & W (length 30 m × inner diameter 2.25 film thickness 0.25 μm)
Internal standard: 2,6-dimethyl-γ-pyrone Column flow rate: 1.8 ml / min Column temperature: held at 50 ° C. for 1 minute. The temperature is raised at a constant rate of 25 ° C./min and maintained at 320 ° C. for 5 minutes.
Detector: Hydrogen flame ionization method (FID)

<Remaining catalyst amount>
Based on the result of the GPC measurement and the result of the GC measurement, the remaining catalyst amount was calculated by the following equation.
Residual catalyst amount = (peak area (wt%) having a molecular weight of 1000 or less determined from the GPC measurement result) − (unreacted monomer amount (wt%) determined from the GC measurement result))

<Monofilament tensile strength>
It was measured under the constant speed extension condition shown in JIS L1030 8.5.1 standard time test.
・ Device: Tensilon UCT-100 type measuring instrument (Orientec Co., Ltd.)
・ Grip interval: 30cm
・ Tensile speed: 30 cm / min ・ Number of tests: 10 times

<Polymerization reactor>
Examples 1-1 to 1-16, Examples 2-1 to 2-13, Examples 3-1 to 1-34, Examples 4-1 to 4-16, and Comparative Examples 1-4 and Comparative Example 2 In -4, Comparative Example 3-4, and Comparative Example 4-4, the polymerization reaction apparatus 200 of FIG. 4 was used. As the cylinder 21 of the polymerization reaction apparatus 200, a CO ₂ cylinder was used. As the reaction vessel 27 of the polymerization reaction apparatus 200, a 100 ml batch type pressure vessel was used.

  In Examples 1-17, 3-15, and 3-16, the continuous polymerization reaction apparatus 100 of FIG. 3 was used. The mixing device 9 has a cylinder inner diameter (d) of 30 mm having a biaxial stirring device to which screws that mesh with each other are attached. The two rotating shafts rotate in the same direction and the speed is 30 rpm. The reaction vessel 13 is a twin-screw kneader (TME-18 manufactured by Toshiba).

[Example 1-1]
L-lactic acid lactide 90 parts by mass, D-lactic acid lactide 10 parts by mass, the initiator lauryl alcohol is 1.00 mol% with respect to 100 mol% of the monomer, and the total mass of the system is 50 g, 100 mL The reaction vessel 27 was added. After heating and melting them at 110 ° C., supercritical carbon dioxide (60 ° C., 15 MPa) was filled with the pump 22 and the raw materials were dissolved while stirring for 10 minutes. After the temperature in the system was adjusted to 60 ° C., the path of the compressive fluid was switched to the addition pot 25. As a result, the organic catalyst (1,8-diazabicyclo [5.4.0] undec-7-ene (DBU), 2.0 mol%) charged in the addition pot 25 in advance is 1 MPa higher than the pressure in the reaction vessel 27. The mixture was pushed out from the addition pot 25 to the reaction vessel 27 at the set pressure. Then, it was made to react for 2 hours. After completion of the reaction, the polymer product was discharged from the valve 28 while reducing the pressure. Thereby, carbon dioxide was vaporized, and a polymer product (polylactic acid) was obtained. The obtained polymer product became a foam by the vaporization of internal carbon dioxide. The obtained polymer product was pulverized by a counter jet mill (manufactured by Hosokawa Micron Corporation) to obtain particles having a volume average particle diameter of 6 μm. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 1.

[Examples 1-2 to 1-4]
Except that the initiator amount was changed as shown in each column of Examples 1-2 to 1-4 in Table 1, the same operation as in Example 1-1 was performed to obtain a polymer product. The obtained polymer product became a foam by the vaporization of internal carbon dioxide. Moreover, about the obtained polymer product, particle | grains were obtained by performing operation similar to Example 1-1. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 1.

[Examples 1-5 to 1-7]
Except that the reaction temperature was changed as shown in each column of Examples 1-5 to 1-7 in Table 1, the same operation as in Example 1-3 was performed to obtain a polymer product. The obtained polymer product became a foam by the vaporization of internal carbon dioxide. Moreover, about the obtained polymer product, particle | grains were obtained by performing operation similar to Example 1-1. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 1.

[Examples 1-8 to 1-10]
Except that the reaction pressure was changed as shown in each column of Examples 1-8 to 1-10 in Table 2, the same operation as in Example 1-3 was performed to obtain a polymer product. The obtained polymer product became a foam by the vaporization of internal carbon dioxide. Moreover, about the obtained polymer product, particle | grains were obtained by performing operation similar to Example 1-1. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 2.

[Examples 1-11 to 1-13]
Except that the reaction time and reaction pressure were changed as shown in Examples 1-1 to 1-13 in Table 2, the same operations as in Example 1-3 were performed to obtain a polymer product. The obtained polymer product became a foam by the vaporization of internal carbon dioxide. Moreover, about the obtained polymer product, particle | grains were obtained by performing operation similar to Example 1-1. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 1-2.

[Examples 1-14 to 1-16]
Except that the monomer species, catalyst species, reaction pressure, and reaction time were changed as shown in Examples 1-14 to 1-16 in Table 3, the same operations as in Example 1-3 were performed to produce a polymer. I got a thing. The obtained polymer product became a foam by the vaporization of internal carbon dioxide. Moreover, about the obtained polymer product, particle | grains were obtained by performing operation similar to Example 1-1. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 3.

[Example 1-17]
The L-lactide and D-lactide mixture (90/10) was polymerized by the continuous polymerization apparatus shown in FIG. As additives, a pigment (CI Pigment Yellow 185), carnauba wax, and a charge control agent (Orient Chemical Industries, Ltd .: E-84) were used in the ratios shown below.
L / D lactide mixture: 93 parts Pigment: 2 parts Carnauba wax: 4 parts Charge control agent: 1 part

  The gear pump (metering feeder 2) is operated to supply the molten lactide in the tank 1 to the mixing device 9 in a fixed amount. The gear pump (metering feeder 4) is operated, and lauryl alcohol as an initiator in the tank 3 is quantitatively supplied to the mixing device 9 so as to be 0.5 mol% with respect to lactide. The temperature of the cylinder of the mixing device 9 is 80 ° C. Carbon dioxide gas is supplied from the vent hole (introduction port 9a) so that the pressure in the system becomes 15 MPa. The metering pump 12 is operated to supply the polymerization catalyst DBU in the tank 11 to the raw material supply hole (introduction port 13b) so as to be 0.1% by mass with respect to lactide. As for the cylinder temperature of the reaction vessel 13, the temperature in the vicinity of the raw material supply unit was 80 ° C., the temperature at the tip was 60 ° C., and the average residence time of the reactants in this vessel was about 1200 seconds. A metering pump and an extrusion die were attached to the tip and extruded into a strand shape to obtain a chip. The polymer product feed rate of the metering pump 14 is 200 g / min.

  Further, the chip was pulverized by a counter jet mill (manufactured by Hosokawa Micron Corporation) to obtain colored particles (toner) having a volume average particle diameter of 6 μm. About the obtained colored particle, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 3.

[Example 1-18]
L-type (100%) lactide is used as the monomer type, the initiator amount is changed to the value shown in Table 4, and carbon dioxide gas is introduced from the vent hole (inlet 9a) at a flow rate of 10 g / min. Except that, the same operation as in Example 1-17 was performed to obtain a polymer product. The flow rate of 10 g / min corresponds to 5 wt% with respect to the polymer product feed rate of the metering pump 14 of 200 g / min. The obtained polymer product (L-form polylactic acid) was foamed by the vaporization of internal carbon dioxide. Moreover, about the obtained polymer product, particle | grains were obtained by performing operation similar to Example 1-1. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 4.

[Example 1-19]
The same operation as in Example 1-18 was performed except that the amount of the initiator was changed to the values shown in Table 4. The polymer product extruded in a strand form from the extrusion die 15 was immersed in water at 10 ° C., and then the strand was cut with a cutter and dried to obtain pellets.

[Example 1-20]
The L-form polylactic acid obtained in Example 1-18 was used as an initiator species, and starting from it, a D-form (100%) lactide was polymerized to produce a stereocomplex. For the production of the stereocompress, the polymerization reaction apparatus 300 shown in FIG. 5 was used. FIG. 5 is a system diagram showing an example of a batch polymerization process. The polymerization reaction apparatus 300 is the same as that shown in FIG. 4 except that it has an addition pot 125, a reaction container 127, valves (123, 124, 126, 128, 129), and a pipe 130 provided with joints (130a, 130b). The polymerization reaction apparatus 200 has the same configuration. The addition pot 125, the reaction vessel 127, the valve (123, 124, 126, 128, 129), and the pipe 130 are respectively added to the addition pot 25, the reaction vessel 27, the valve (23, 24, 26, 28, 29), It is comprised by the apparatus, mechanism, or means similar to the piping 30. The operation in Example 1-20 is as follows.

  25 g of the polymer product obtained in Example 1-18 was charged into the batch cell (reaction vessel 27) of FIG. 5, heated to 200 ° C., and dissolved for 1 hour. Subsequently, carbon dioxide gas in the tank 21 was filled so that the internal pressure was 10 MPa, and cooling was performed for 1 hour until the temperature of the polymer product reached 100 ° C. Thereafter, an organic catalyst (DMAP: N, N-dimethyl-4-aminopyridine) previously charged in the addition pot 25 as a catalyst is extruded into the reaction vessel 27 at a pressure higher than the pressure (10 MPa) in the reaction vessel 27. In addition, the pressure in the reaction vessel 27 was set to 12 MPa and left for 2 hours.

  Subsequently, the molten D-form (100%) of lactide (110 ° C.) charged in the addition pot 125 is put in the reaction vessel 27 at a pressure higher than the pressure in the reaction vessel 27 (12 MPa) in the same manner as the organic catalyst. The reaction was carried out for 2 hours at a pressure of 15 MPa. After completion of the reaction, the compressive fluid and the polymer product were discharged from the valve 28 while reducing the pressure, and a polylactic acid stereocomplex copolymer was obtained. Moreover, about the obtained polymer product, the pellet was obtained by performing operation similar to Example 1-18. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 4.

[Comparative Example 1-1]
Under normal pressure conditions (0.1 MPa), 90 parts by weight of lactide of L-lactic acid, 10 parts by weight of lactide of D-lactic acid, and 0.5 mole% of lauryl alcohol as an initiator with respect to 100 mole% of the monomer, Weighed in a flask to a weight of 50 g. Next, the temperature was further raised under N ₂ purge, and after confirming that the system was homogenized by visual observation, 2 mol% of 2-ethylhexanoic acid tin was added as a catalyst to conduct a polymerization reaction. At this time, the temperature in the system was controlled so as not to exceed 190 ° C. After the reaction time of 2 hours, unreacted lactide was removed under reduced pressure, and the polymer product (polylactic acid) in the flask was taken out. The removed polymer product was pulverized by a counter jet mill (manufactured by Hosokawa Micron Corporation) to obtain particles having a volume average particle diameter of 7 μm. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 3.

[Comparative Examples 1-2 and 1-3]
Except that the monomer type was changed as shown in Comparative Examples 1-2 and 1-3 in Table 3, the same operation as in Comparative Example 1-1 was performed to obtain particles. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 3.

[Comparative Example 1-4]
90 parts by mass of lactide of L-lactic acid, 10 parts by mass of lactide of D-lactic acid, 1.00 mol% of lauryl alcohol as an initiator with respect to 100 mol% of monomer, 1,8-diazabicyclo [5.4.0 as an organic catalyst ] Undec-7-ene (DBU) was set to 2.0 mol%, and the total mass of the system was weighed to 50 g and added to a 100 mL pressure vessel. The difference from Example 1-1 is the timing of adding the organic catalyst. Thereafter, supercritical carbon dioxide (60 ° C., 15 MPa) was filled in the pressure vessel, and the reaction was performed for 2 hours after the temperature in the system reached 60 ° C. After completion of the reaction, the compressive fluid and the polymer product were discharged from the valve 28 while reducing the pressure. Thereby, carbon dioxide was vaporized, and a polymer product (polylactic acid) was obtained. The obtained polymer product was pulverized by a counter jet mill (manufactured by Hosokawa Micron Corporation) to obtain particles having a volume average particle diameter of 6 μm. About the obtained particle | grains, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 3. In Comparative Example 1-4, a part of the foam was not uniform, and a polymer product in a state of being mixed with bulk particles was obtained. Although the detailed reason is unknown, it is considered that this is because the polymer has a small number average molecular weight, and the elasticity of the polymer at the time of vaporization of the compressive fluid is less than the elasticity necessary for forming air holes.

  Table 5 shows the glass transition temperature and softening point data measured by the above method for the polymer products obtained in Example 1-1 and Comparative Example 1-4. Since the particles of Comparative Example 1-4 have a low molecular weight, the thermal properties indicated by the glass transition temperature and the softening point are low, and there is a possibility of particle coalescence under high temperature conditions, which limits the use in applications. The

<Example of toner production>
A toner may be produced by adding a pigment, WAX, a charge control agent, or the like to the polymer product obtained in each example such as Example 1-1, pulverization and classification after melt kneading. An example of toner production in this case is shown.

The masterbatch raw materials shown below were mixed with a Henschel mixer to obtain a mixture in which water was soaked into the pigment aggregate.
(Master batch raw material)
Pigment (CI Pigment Yellow 185): 40 parts Polymer product (Example 1-1): 60 parts Water: 30 parts This was kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. A master batch was obtained by pulverizing to a size of 1 mmφ with a pulverizer.

Carnauba wax ((molecular weight 1,800, acid value 2.7 mg KOH / g, penetration 1.7 mm (40 ° C.)), master batch, charge control agent (manufactured by Orient Chemical Industries: E -84) was added and kneaded at 100 ° C. using a biaxial extruder, and pulverized and classified to obtain toner particles, and then 100 parts of the toner particles were mixed with 0.5 part of hydrophobic silica and hydrophobized and oxidized. 0.5 part of titanium was mixed with a Henschel mixer to obtain a toner.
(Toner prescription)
Polymer product (Example 1-1): 90 parts Carnauba wax: 4 parts Masterbatch: 5 parts Charge control agent: 1 part

[Production of foam]
Furthermore, 100 parts by mass of the polymer product obtained in Comparative Examples 1-1 to 1-4, talc (manufactured by Matsumura Sangyo Co., Ltd., high filler # 12; average particle size 3) as a nucleating agent (bubble adjusting agent) ~ 4μm) 0.2 parts by mass with an open roll kneader (Nedex Nippon Coke Kogyo Co., Ltd.) front roll supply side 120 ° C, discharge side 80 ° C, back roll supply side 30 ° C, discharge side 20 ° C, front roll rotation After kneading once at several 35 rpm, a back roll rotation number of 31 rpm, and a gap of 0.25 mm, the mixture was pulverized with a pulverizer (manufactured by Hosokawa Micron Corporation) to prepare polymer particles.

100 parts by weight of the obtained polymer particles, 300 parts by weight of pure water, 0.02 part by weight of tricalcium phosphate (average particle size 0.5 μm) as an anti-fusing agent, and sodium dodecylbenzenesulfonate as a dispersant 0.0006 part by weight was placed in an autoclave having an internal volume of 500 mL, nitrogen gas was introduced, and oxygen in the autoclave was removed. While stirring the contents, the temperature was raised to the foaming temperature (105 ° C.), carbon dioxide was injected until the autoclave pressure reached 45 kgf / cm ² G (3.9 MPa), and the temperature was maintained for 60 minutes. Thereafter, the content was cooled to 95 ° C. and held at that temperature for 5 minutes, and then one end of the autoclave was opened to obtain expanded particles under atmospheric pressure.

The bulk density of each example and each comparative example was 0.030 ± 0.005 g / cm ² , and the thermal conductivity was 0.035 ± 0.005 (W / m · K). Each foam of an Example and a comparative example can be used for uses, such as a shock absorbing material, a heat insulating material, a soundproof material, and a damping material. However, their compressive strength is almost correlated with the molecular weight of the polymer. When the molecular weight of the polymer is less than 15000, there is a concern that the durability and heat resistance of the foam containing the polymer may be insufficient depending on the application. In addition, from the results shown in Tables 1 to 3, the foams of the examples are superior to the foams of the comparative examples with respect to the stability of the foams themselves and the safety concerned from the residual catalyst. Is judged. Furthermore, the foam of each Example is manufactured simultaneously with the vaporization of carbon dioxide. That is, the foam of an Example is manufactured efficiently compared with the foam of a comparative example.

[Example 2-1]
A polymer product (polylactic acid) was obtained by performing the same operation as in Example 1-1 except that the initiator lauryl alcohol was changed to 0.175 mol% with respect to 100 mol% of the monomer. The obtained polymer product was subjected to film molding with a general-purpose inflation molding machine so that the molding temperature was 200 ° C. and the thickness was 100 μm. About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 6.

[Examples 2-2 to 2-3]
A stretched film was obtained by performing the same operation as in Example 2-1, except that the amount of the initiator was changed as shown in each column of Examples 2-2 to 2-3 in Table 6. About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 6.

[Examples 2-4 to 2-6]
Except that the reaction temperature was changed as shown in each column of Examples 2-4 to 2-6 in Table 6, the same operation as in Example 2-2 was performed to obtain a stretched film. About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 6.

[Examples 2-7 to 2-8]
Except that the reaction pressure was changed as shown in each column of Examples 2-7 to 2-8 in Table 7, the same operation as in Example 2-2 was performed to obtain a stretched film. About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 7.

[Examples 2-9 to 2-10]
Except that the reaction time and reaction pressure were changed as shown in each column of Examples 2-9 to 2-10 in Table 7, the same operation as in Example 2-2 was performed to obtain a stretched film. . About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 7.

[Examples 2-11 to 2-13]
Except that the monomer species, catalyst species, and reaction time were changed as shown in Examples 2-11 to 2-13 in Table 8, the same operations as in Example 2-2 were performed to obtain a stretched film. . About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 8.

[Comparative Example 2-1]
A polymer product (polylactic acid) was obtained in the same manner as in Comparative Example 1-1 except that the initiator lauryl alcohol was changed to 0.15 mol% with respect to 100 mol% of the monomer. The obtained polymer product was subjected to film molding with an inflation molding machine so that the molding temperature was 200 ° C. and the thickness was 100 μm. About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 8.

[Comparative Examples 2-2 and 2-3]
A stretched film was obtained in the same manner as in Comparative Example 2-1, except that the monomer type was changed as shown in Comparative Example 2-2 and 2-3 columns of Table 8. About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 8.

[Comparative Example 2-4]
The same operation as in Comparative Example 1-4 was performed to obtain a polymer product (polylactic acid). The obtained polymer product was subjected to film molding with a general-purpose inflation molding machine so that the molding temperature was 200 ° C. and the thickness was 100 μm. About the obtained stretched film, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 8.

  When the number average molecular weight of the polymer contained in the stretched film is less than 15000 (Comparative Example 2-4), there is a concern that the durability of the stretched film may be insufficient depending on the application. Further, from the results shown in Tables 6 to 8, the stretched film of the example is superior to the stretched film of Comparative Examples 1-1 to 1-3 in terms of stability and safety due to the residual catalyst and the residual monomer. It is judged that

[Example 3-1]
A polymer product (polylactic acid) was obtained in the same manner as in Example 1-1 except that the initiator lauryl alcohol was changed to 0.1 mol% with respect to 100 mol% of the monomer. About the obtained polymer product, it melt-kneaded at 230 degreeC with the twin-screw kneader (TOSHIBA make TME-18) which attached the metering pump and the extrusion nozzle at the front-end | tip, it extrudes in strand shape, and 10 degreeC water is submerged. After immersing, the strand was cut with a cutter and dried to obtain pellets. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 9.

[Example 3-2]
Except that the initiator amount was changed as shown in the column of Example 3-2 in Table 9, the same operation as in Example 3-1 was performed to obtain a pellet. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 9.

[Examples 3-3 to 3-5]
Except that the reaction temperature was changed as shown in each column of Examples 3-3 to 3-5 in Table 9, the same operation as in Example 3-2 was performed to obtain pellets. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 9.

[Examples 3-6 to 3-8]
Except that the reaction pressure was changed as shown in each column of Examples 3-6 to 3-8 in Table 1, the same operation as in Example 3-2 was performed to obtain pellets. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 9.

[Examples 3-9 to 3-11]
Except that the reaction time and reaction pressure were changed as shown in the columns of Examples 3-9 to 3-11 in Table 9, the same operations as in Example 3-2 were performed to obtain pellets. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 9.

[Examples 3-12 to 3-14]
Except that the monomer species, catalyst species, reaction pressure, and reaction time were changed as shown in each column of Examples 3-12 to 3-14 in Table 9, the same operation as in Example 3-2 was performed, Pellets were obtained. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 9.

[Example 3-15]
The gear pump (metering feeder 2) is operated to supply the molten lactide in the tank 1 to the mixing device 9 in a fixed amount. The gear pump (metering feeder 4) is operated, and lauryl alcohol as an initiator in the tank 3 is quantitatively supplied to the mixing device 9 so as to be 0.1 mol% with respect to lactide. The temperature of the cylinder of the mixing device 9 is 80 ° C. Carbon dioxide gas is supplied from the vent hole (introduction port 9a) so that the pressure in the system becomes 15 MPa. The metering pump 12 is operated to supply the polymerization catalyst DBU in the tank 11 to the raw material supply hole (introduction port 13b) so as to be 0.1% by mass with respect to lactide. As for the cylinder temperature of the reaction vessel 13, the temperature in the vicinity of the raw material supply unit was 80 ° C., the temperature at the tip was 60 ° C., and the average residence time of the reactants in this vessel was about 1200 seconds. A metering pump and an extrusion die were attached to the tip, extruded into a strand shape, submerged in water at 10 ° C., then the strand was cut with a cutter and dried to obtain pellets. The polymer product feed rate of the metering pump 14 is 200 g / min. About the obtained pellet, the physical-property value as a polymer product was calculated | required by the above-mentioned method. The results are shown in Table 10.
[Example 3-16]
Except that the initiator amount was changed as shown in the column of Example 3-16 in Table 10, the same operation as in Example 3-15 was performed to obtain a pellet. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 10.

[Comparative Example 3-1]
A polymer product (polylactic acid) was obtained in the same manner as in Comparative Example 1-1 except that the initiator lauryl alcohol was changed to 0.1 mol% with respect to 100 mol% of the monomer. About the obtained polymer product, it melt-kneaded at 230 degreeC with the twin-screw kneader (TOSHIBA make TME-18) which attached the metering pump and the extrusion nozzle at the front-end | tip, it extrudes in strand shape, and 10 degreeC water is submerged. After immersing, the strand was cut with a cutter and dried to obtain pellets. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 11.

[Comparative Examples 3-2, 3-3, 3-4]
Except that the amount of the initiator and the monomer type were changed as shown in each column of Comparative Examples 3-2, 3-3 and 3-4 in Table 11, the same operation as in Comparative Example 3-1 was performed, and the pellets were Obtained. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 11.

[Comparative Example 3-5]
The same operation as in Comparative Example 1-4 was performed to obtain a polymer product (polylactic acid). About the obtained polymer product, it melt-kneaded at 230 degreeC with the twin-screw kneader (TOSHIBA make TME-18) which attached the metering pump and the extrusion nozzle | tip at the front-end | tip, and it extrudes in strand form, and 10 degreeC water After immersing, the strand was cut with a cutter and dried to obtain pellets. Pellets were obtained. About the obtained pellet, the physical-property value as a polymer product was calculated | required by said method. The results are shown in Table 11.

[Manufacture of sheets]
Using the pellets obtained in each Example and Comparative Example, using a single screw extruder (SE-90CV manufactured by Toshiba Machine) with a screw diameter of 90 mm equipped with a T die having a width of 1000 mm, at an extrusion temperature of 215 ° C. The sheet was melt-extruded and adhered to a cast roll set at 40 ° C. to obtain a sheet having a thickness of 350 μm.

[Manufacture of sheet molded products]
Using each sheet obtained in the sheet production example as a material, using a hot plate pressure forming machine (FKH type small hot plate heating type pressure forming machine manufactured by Asano Laboratory Co., Ltd.) and an aluminum mold, A box-shaped container having a length of 250 mm, a width of 200 mm, and a depth of 30 mm was molded. The heating hot plate temperature (heating softening temperature) at the time of molding was 120 ° C., the mold surface temperature was 117 ° C., the heating time required for molding was 10 seconds, the cooling time was 5 seconds, and the shot cycle was 15 seconds. The molded semi-finished product was punched with a punch using a Thomson blade to obtain a sheet molded product.

[Manufacture of injection molded products]
Using the pellets obtained in each Example and Comparative Example, respectively, with a screw type vertical injection molding machine (TKP-30-3HS manufactured by Tabata Machinery Co., Ltd.), at a molding temperature of 200 ° C., 50 mm length, 50 mm width, An injection molded product having a thickness of 5 mm was molded.

[Evaluation of sheets, sheet molded products, and injection molded products]
The obtained sheets, sheet molded products, and injection molded products were evaluated according to the following criteria. The evaluation results are shown in Tables 9 to 11.
Sheet rating:
A sample having a length of 1000 mm and a width of 1000 mm was visually observed to confirm whether there was a fish-eye-like foreign material and evaluated.
No fish-eye foreign matter: ○
There are 1 or 2 fisheye-like foreign matters: Δ
There are 3 or more fish-eye foreign objects: ×
Sheet molded product evaluation:
100 sheet molded product samples were produced, and evaluated as follows from the moldability and appearance in that case.
No problem in formability and appearance: ○
There is a slight problem in moldability and appearance: (Since 1 to 9 samples, cracking occurs at least during molding or punching, and it becomes slightly turbid visually): Δ
There is a clear problem in formability and appearance: (Wrapping occurs in at least 10 moldings or punching, and it is clearly cloudy visually): ×
Evaluation of injection molded products:
100 injection molded products were produced, and the following evaluation was performed from the moldability and appearance in that case.
No problem in formability and appearance: ○
There is a slight problem in moldability and appearance (burrs are generated in 1 to 9 samples, and it is slightly turbid visually): Δ
There is a clear problem in moldability and appearance (10 or more samples have many burrs, and they are clearly cloudy visually): ×

  From the results shown in Tables 3-1 to 3-3, the stability, safety, and moldability due to the residual catalyst and residual monomer are more examples than the sheets or molded articles of Comparative Examples 3-1 to 3-4. It is judged that the sheet or molded product is superior. Moreover, when the number average molecular weight of the polymer contained in the sheet or the molded product is less than 15000 (Comparative Examples 3-2 and 3-5), the moldability deteriorates.

[Example 4-1]
A polymer product (polylactic acid) was obtained in the same manner as in Example 1-1 except that the initiator lauryl alcohol was changed to 0.25 mol% with respect to 100 mol% of the monomer. The obtained polymer product was spun by a known simple melt spinning machine (Capillograph 1D PMD-C manufactured by Toyo Seiki Co., Ltd.) and drawn by a hot air drawing machine to obtain a monofilament. About the obtained monofilament, the physical property and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 12.

[Examples 4-2 to 4-3]
A monofilament was obtained in the same manner as in Example 4-1, except that the initiator amount was changed as shown in each column of Examples 4-2 to 4-3 in Table 12. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 12.

[Examples 4-4 to 4-6]
A monofilament was obtained in the same manner as in Example 4-2, except that the reaction temperature was changed as shown in each column of Examples 4-4 to 4-6 in Table 12. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 12.

[Examples 4-7 to 4-9]
A monofilament was obtained in the same manner as in Example 4-2, except that the reaction pressure was changed as shown in each column of Examples 4-7 to 4-9 in Table 13. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 13.

[Examples 4-10 to 4-12]
A monofilament was obtained in the same manner as in Example 4-2, except that the reaction time and reaction pressure were changed as shown in each column of Examples 4-10 to 4-12 in Table 13. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 13.

[Examples 4-13 to 4-15]
Except that the monomer species, catalyst species, reaction pressure, and reaction time were changed as shown in the columns of Examples 4-13 to 4-15 in Table 14, the same operations as in Example 4-2 were performed, A monofilament was obtained. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 14.

[Example 4-16]
About the polymer product manufactured in the same manner as in Example 4-2, using a spunbond nonwoven fabric manufacturing apparatus (manufactured by Shinwa Kogyo Co., Ltd.), melt spinning, cooling, stretching, opening, deposition, deposition, A nonwoven fabric was obtained by heat treatment.

[Comparative Example 4-1]
A polymer product (polylactic acid) was obtained in the same manner as in Comparative Example 1-1 except that the initiator lauryl alcohol was changed to 0.1 mol% with respect to 100 mol% of the monomer. The obtained polymer product was spun by a known simple melt spinning machine (Capillograph 1D PMD-C manufactured by Toyo Seiki Co., Ltd.) and drawn by a hot air drawing machine to obtain a monofilament. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 14.

[Comparative Examples 4-2 and 4-3]
A monofilament was obtained in the same manner as in Comparative Example 4-1, except that the monomer type was changed as shown in each column of Comparative Examples 4-2 and 4-3 in Table 3. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 14.

[Comparative Example 4-4]
90 parts by mass of lactide of L-lactic acid, 10 parts by mass of lactide of D-lactic acid, 0.25 mol% of initiator lauryl alcohol with respect to 100 mol% of monomer, 1,8-diazabicyclo [5.4.0 as an organic catalyst ] Undec-7-ene (DBU) was set to 2.0 mol%, and the total mass of the system was weighed to 50 g and added to a 100 mL pressure vessel. The difference from Example 4-1 is the timing of adding the organic catalyst. Thereafter, supercritical carbon dioxide (60 ° C., 15 MPa) was charged, and after the temperature in the system reached 60 ° C., the reaction was performed for 2 hours. After completion of the reaction, the temperature was gradually returned to normal temperature and normal pressure, and the compressive fluid and polymer product were discharged from the valve 28 while reducing the pressure. Thereby, carbon dioxide was vaporized, and a polymer product (polylactic acid) was obtained. The obtained polymer product was spun by a known simple melt spinning machine (Capillograph 1D PMD-C manufactured by Toyo Seiki Co., Ltd.) and drawn by a hot air drawing machine to obtain a monofilament. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 3.

[Comparative Example 4-5]
A monofilament was obtained in the same manner as in Example 4-1, except that the initiator amount was changed as shown in the column of Comparative Example 4-5 in Table 14. About the obtained monofilament, the physical-property value and tensile strength as a polymer product were calculated | required by said method. The results are shown in Table 14.

  The tensile strength of monofilaments is almost correlated with the molecular weight of the polymer. When the number average molecular weight of the polymer contained in the fiber is less than 15000 (Comparative Example 4-5), there is a concern that the durability of the fiber may be insufficient depending on the application. Further, from the results shown in Tables 12 to 14, the fibers of the examples are superior to the fibers of Comparative Examples 4-1 to 4-4 with respect to the stability and safety of the fibers caused by the residual catalyst and the residual monomers. It can be easily judged.

1 Tank 2 Metering Feeder 3 Tank 4 Metering Feeder 5 Tank 6 Metering Pump 7 Tank 8 Metering Pump 9 Mixing Device 10 Liquid Pump 11 Tank 12 Metering Pump 13 Reaction Container 14 Metering Pump 15 Extrusion Cap 21 Tank 22 Pump 23 Valve 24 Valve 25 Addition pot 26 Valve 27 Pressure vessel 28 Valve 100 Polymerization reactor 200 Polymerization reactor

JP-A-8-259676 JP 2008-63420 A JP 2005-60474 A JP 2009-1614 A

Ganapathy, H.S .; Hwang, H.S .; Jeong, Y. T .; LEE, W-T .; Lim, K. T. Eur Polym J. 2007, 43 (1), 119-126. Idriss Blakey, Anguang Yu, Steven M. Howdle, Andrew K. Whittakera and Kristofer J. Thurechta, Green Chemistry, 2011, Advance Article "Latest application technology of supercritical fluid", p. 173, March 15, 2004, issued by NTS Corporation

Claims (21)

  A polymer product characterized by being substantially free of an organic solvent and a metal catalyst, having a residual ring-opening polymerizable monomer amount of 1000 ppm or less, and a number average molecular weight of 15000 or more.   The polymer product according to claim 1, wherein a value obtained by dividing the weight average molecular weight by the number average molecular weight is 1.2 or more and 2.5 or less.   The polymer product according to claim 1 or 2, wherein the ring-opening polymerizable monomer is a monomer having an ester bond in the ring.   The polymer product according to claim 3, wherein the monomer having an ester bond in the ring is a cyclic ester or a cyclic carbonate. The polymer product according to claim 4, wherein the cyclic ester is a cyclic dimer obtained by dehydrating condensation of a compound represented by the general formula (1).
R—C—H (—OH) (—COOH) [General Formula (1)]
(However, R represents an alkyl group having 1 to 10 carbon atoms.)   6. The polymer product according to claim 5, wherein the cyclic dimer is lactide of lactic acid.   The polymer production according to any one of claims 1 to 6, which is obtained by ring-opening polymerization of a ring-opening polymerizable monomer using a compressive fluid and an organic catalyst containing no metal atom. object.   The polymer product according to claim 7, wherein the residual amount of the organic catalyst is less than 2 wt%.   The polymer product according to claim 7 or 8, wherein the compressive fluid contains carbon dioxide.   10. The polymer product according to claim 7, wherein the organic catalyst is a nucleophilic nitrogen compound having basicity.   The polymer product according to any one of claims 7 to 10, wherein the organic catalyst is a cyclic compound containing a nitrogen atom.   The polymer product according to any one of claims 7 to 11, wherein the organic catalyst contains a cyclic monoamine, a cyclic diamine, a cyclic triamine, or a heterocyclic compound.   The organic catalyst is 1,4-diazabicyclo- [2.2.2] octane, 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,5,7-triazabicyclo [4. 4.0] Deca-5-ene, diphenylguanidine, N, N-dimethyl-4-aminopyridine, 4-pyrrolidinopyridine, or 1,3-di-tert-butylimidazol-2-ylidene A polymer product according to any one of claims 7 to 12, characterized in that   The polymer product according to any one of claims 1 to 13, which is a copolymer having two or more kinds of polymer segments.   The polymer product according to claim 1, wherein the polymer product is a stereocomplex.   16. The polymer product according to any one of claims 1 to 15, wherein the polymer product is white.   A molded product comprising the polymer product according to any one of claims 1 to 16.   The molded product according to claim 17, wherein the polymer product is polylactic acid.   A medical molded article comprising the polymer product according to any one of claims 1 to 16 and having biodegradability.   A toner comprising the polymer product according to any one of claims 1 to 16.   A polymer composition comprising the polymer product according to any one of claims 1 to 16.

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