JP4196174B2 - Method for producing polyether polymer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a polyether polymer. More specifically, the present invention relates to a method for producing a polyether polymer in which a polyether polymer is slurry-polymerized in a reaction tank using an agitating blade in an organic solvent.
[0002]
[Prior art]
Polyether polymers obtained by polymerizing oxirane monomers such as alkylene oxides are in the spotlight as solid polymer electrolytes used in batteries, capacitors, capacitors and the like. A polymer solid electrolyte using a polyether polymer is excellent in processability and flexibility, so that it has a high degree of freedom in shape when applied to a battery. Further, since it does not contain an electrolytic solution, it is excellent in safety.
As a method for producing a polyether polymer, there are mainly a solution polymerization method using a solvent in which both the monomer and the polymer are soluble, and a slurry using a solvent in which the monomer is dissolved but the polymer is not dissolved. There is a polymerization method. In general, the slurry polymerization method is advantageous because the separation of the polymer is simpler than the solution polymerization method. In particular, in the case of producing a water-soluble polymer having ethylene oxide as a main monomer, it is practically indispensable to apply a slurry polymerization method because the polymer cannot be separated by steam stripping.
[0003]
However, the slurry polymerization method has a problem that a polymer precipitated in the course of the polymerization reaction adheres to the walls in the reaction tank and the stirring blade. If scale adheres to the inner wall, the heat transfer efficiency decreases, so it is necessary to reduce the reaction rate to the extent that the reaction heat corresponding to the reduced jacket heat removal capability is generated or to reduce the amount of charged monomer. Further, since the amount of scale adhesion increases with the progress of the number of polymerization reactions, it is necessary to remove the scale by human power or a high-pressure water washer at some point. The descaling operation reduces the number of polymerization reactions within a certain period. Thus, scale deposition is a problem for the productivity of polyether polymer production.
On the other hand, when slurry polymerization is further performed using a reaction tank having scales attached to the inner wall and the stirring blade, a quality problem also occurs. That is, the produced polymer particles remain during the undulation of the scale, and this is mixed into the slurry of the subsequent polymerization batch as hard coarse particles. For example, the extrusion rate is obtained when the obtained polyether polymer is extruded. Is disturbed to change the film thickness, or form an opaque part with insufficient melting in the film.
Therefore, it is required to establish a scale adhesion prevention method when industrially producing a polyether polymer by a slurry polymerization method.
[0004]
Concerning prevention of scale adhesion in the polymerization reactor in slurry polymerization of oxirane monomer, polymerization is performed by a mixture of a monomer that gives a polymer soluble in the polymerization solvent and a monomer that gives a polymer insoluble in the polymerization solvent. There has been proposed a method of previously treating a catalyst for use (see Patent Document 1). According to this method, the scale adhesion is greatly reduced. However, if a further device on the manufacturing apparatus that hardly generates scale is added to this method, a more complete scale adhesion prevention technique can be realized.
[0005]
[Patent Document 1]
JP-A-10-195190
[0006]
[Problems to be solved by the invention]
An object of the present invention is to prevent the adhesion of scale in the polymerization reaction tank by applying appropriate stirring conditions when polymerizing the oxirane monomer by the slurry polymerization method, thereby stabilizing the polyether weight of stable quality. The object is to provide a method for producing a coalescence with high productivity.
[0007]
[Means for Solving the Problems]
As a result of intensive studies to solve the above-mentioned problems, the present inventors have obtained a paddle having a specific shape as a stirring blade for polymerization reaction in slurry polymerization of an oxirane monomer in the presence of a catalyst in an organic solvent. By using the blade, it was found that the scale hardly adhered in the reaction vessel, and thus a stable quality polyether polymer could be produced with high productivity, and the present invention was completed based on this finding.
[0008]
  Thus, according to the present invention, the following inventions 1 to 4 are provided.
1. A method for producing a polyether polymer in which an oxirane monomer is slurry-polymerized in an organic solvent in the presence of a catalyst, wherein a polyether polymer seed is formed using a part of the oxirane monomer in a first reaction tank. Forming (A), andCharge the remaining oxirane monomer to the second reaction layer,In the second reaction vessel, in the presence of the polyether polymer seed obtained by step (A).AboveA step (B) of slurry-polymerizing the remaining oxirane monomer to form a polyether polymer slurry, and in step (B), as a stirring blade attached at least to the lowermost portion of the stirring shaft, Using a paddle blade having a shape in which the shortest distance from an arbitrary point above to the tank bottom is substantially constant and the upper edge of the blade descends from the end on the stirring shaft side toward the end on the tank wall side, Before the reaction liquid containing the polyether polymer seed obtained in A) is received in the second reaction tank in which the step (B) is performed, the inside of the second reaction tank is wetted with an organic solvent used for slurry polymerization. A method for producing a polyether polymer characterized by the above.
2. 2. The method for producing a polyether polymer according to 1 above, wherein the angle formed by the upper edge of the paddle blade with the horizontal direction is 2 to 20 degrees on the projection plane onto the plane including the stirring shaft.
3. 3. The method for producing a polyether polymer according to 1 or 2 above, wherein the paddle blade has a retreat degree of 2 to 70 degrees.
4). Required stirring power of paddle blade is 0.005-0.5kW / m³The manufacturing method of the polyether polymer in any one of said 1-3 which is.
[0009]
[Action]
Since the paddle blade used in the polymerization reaction tank in the method of the present invention has a substantially constant clearance between the blade and the tank bottom, the reaction liquid at the bottom of the tank does not cause turbulent flow by the rotation of the paddle blade toward the tank wall. Eliminated. Further, since the upper edge of the paddle blade has a shape that descends from the stirring shaft side end toward the tank wall side end, the reaction liquid removed toward the tank wall is less likely to be caught in the paddle blade again. Most of them are neatly discharged upward along the wall surface. As a result, the bottom surface and the vicinity of the wall surface in the reaction tank are in a steady flow, and hardly generate scale.
In order to obtain this effect, the angle between the upper edge of the paddle blade and the horizontal direction is preferably 2 to 20 degrees on the projection plane, and the paddle blade preferably has a receding degree of 2 to 70 degrees and requires stirring. Power is 0.02-0.5kW / m³It is preferable that
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The method for producing a polyether polymer according to the present invention comprises a stirring blade attached at least to the lowermost part of a stirring shaft when slurry polymerization of an oxirane monomer is carried out in the presence of a catalyst in an organic solvent in a reaction vessel. The shortest distance from any point on the edge to the bottom of the tank is substantially constant, and a paddle blade having a shape in which the upper edge of the blade descends from the end on the stirring shaft side toward the end on the tank wall side is used. It is a feature.
[0011]
Although the oxirane monomer used for this invention is not specifically limited, It is preferable to use an ethylene oxide monomer (a) as at least one component. Further, the oxirane monomer is composed of 70 to 99 mol%, preferably 80 to 99%, more preferably 85 to 95% of the ethylene oxide monomer (a), and an oxirane monomer (b) copolymerizable with ethylene oxide. ) Is preferably a monomer mixture containing 30 to 1 mol%, preferably 20 to 1%, more preferably 15 to 5%.
If the proportion of the ethylene oxide monomer (a) in the oxirane monomer is too small, the mechanical strength and ionic conductivity of the molded product such as a solid electrolyte film produced using the obtained polyether polymer are insufficient. On the contrary, if the amount is too large, the ionic conductivity of the molded body may be lowered.
[0012]
Examples of the oxirane monomer (b) copolymerizable with ethylene oxide include alkylene oxides having 3 to 20 carbon atoms, glycidyl ethers having 4 to 10 carbon atoms, oxides of aromatic vinyl compounds, and crosslinkability to these oxirane monomers. And a crosslinkable oxirane monomer having a group introduced therein.
[0013]
The oxirane monomer (b) copolymerizable with ethylene oxide may be used alone or in combination of two or more. In the present invention, the alkylene oxide having 3 to 20 carbon atoms is used. Or / and an oxirane monomer such as glycidyl ether having 4 to 10 carbon atoms is preferably used as at least one component thereof, and an alkylene oxide having 3 to 20 carbon atoms is more preferably used as at least one component thereof. Examples of the alkylene oxide having 3 to 20 carbon atoms include propylene oxide and 1,2-epoxybutane.
[0014]
Moreover, it is preferable to use a crosslinkable oxirane monomer as at least one component of the oxirane monomer (b). The crosslinkable oxirane monomer is a monomer obtained by introducing a crosslinkable group into the above oxirane monomer such as alkylene oxide having 3 to 20 carbon atoms or glycidyl ether having 4 to 10 carbon atoms. When such a crosslinkable oxirane monomer is used, it is necessary to use a crosslinkable oxirane monomer having a crosslinkable group that can be crosslinked with light or peroxide, such as a vinyl group, a hydroxyl group, and an acid anhydride group. Among these, it is more preferable to use a crosslinkable oxirane monomer having a vinyl group.
[0015]
Specific examples of the crosslinkable oxirane monomer having a vinyl group include ethylenically unsaturated glycidyl ethers, diene or polyene monoepoxides, alkenyl epoxides, and glycidyl esters of ethylenically unsaturated carboxylic acids. Among these, ethylenically unsaturated glycidyl ether is preferable, and examples thereof include vinyl glycidyl ether and allyl glycidyl ether.
Furthermore, in this invention, you may use together the oxirane monomer which has halogen atoms, such as epichlorohydrin and epibromohydrin, besides the crosslinkable oxirane monomer which can be bridge | crosslinked with said light or a peroxide.
[0016]
When the oxirane monomer (b) contains a cross-linkable oxirane monomer, particularly a cross-linkable oxirane monomer that can be cross-linked with light or peroxide, the resulting polyether polymer can be cross-linked by ultraviolet rays or heat. It becomes easy. When the oxirane monomer (b) contains a crosslinkable oxirane monomer, the amount thereof is usually 9 mol% or less, preferably 7 mol% or less, more preferably based on the total oxirane monomer. 5 mol% or less.
[0017]
Although it does not specifically limit as a polymerization catalyst for ring-opening-polymerizing the said oxirane monomer and obtaining a polyether polymer, The following catalyst can be illustrated. Examples of homogeneous catalysts include a system in which water and acetylacetone are reacted with organoaluminum (see Japanese Patent Publication No. 35-15797), and a system in which phosphoric acid and triethylamine are reacted with triisobutylaluminum (Japanese Patent Publication No. 46-27534). And a system in which phosphoric acid and an organic acid salt of diazabicycloundecene are reacted with triisobutylaluminum (see Japanese Examined Patent Publication No. 56-51171). Examples of the catalyst in which the prepared catalyst is heterogeneous or solid include a system comprising a partially hydrolyzed aluminum alkoxide and an organic zinc compound (see Japanese Patent Publication No. 43-2945), an organic zinc compound, and Examples thereof include a system comprising a polyhydric alcohol (see Japanese Patent Publication No. 45-7751), a system comprising a dialkylzinc and water (see the Japanese Patent Publication No. 36-3394 construction method), and the like.
In the case of using a homogeneous catalyst, the catalyst for slurry polymerization is pretreated with a mixture of a monomer that gives a polymer soluble in the polymerization solvent and a monomer that gives a polymer insoluble in the polymerization solvent. This method is preferable because scale adhesion is further reduced.
[0018]
In the method of the present invention, a slurry polymerization method using an organic solvent in which the produced polymer is insoluble is employed.
The organic solvent is not particularly limited as long as it does not dissolve the produced polymer and does not deactivate the polymerization catalyst. For example, aromatic hydrocarbons such as benzene and toluene; chain saturated hydrocarbons such as n-pentane and n-hexane; alicyclic hydrocarbons such as cyclopentane and cyclohexane;
[0019]
In the method of the present invention, the above-mentioned oxirane monomer is slurry-polymerized in the presence of a catalyst in an organic solvent in a reaction vessel having a stirring blade attached to a stirring shaft. The method of the present invention is the shortest from the arbitrary point on the lower edge of the blade to the bottom of the reaction tank (tank bottom) as a stirring blade attached at least to the lowermost part of the stirring shaft in the slurry polymerization performed in the reaction tank. A paddle blade having a shape in which the distance is substantially constant and the upper edge of the blade descends from the end on the stirring shaft side toward the end on the wall (tank wall) side of the reaction vessel is used.
The paddle blade is a stirring blade in which 2 to 8 blades, preferably 2 to 4 blades are arranged symmetrically with respect to the stirring axis, as in the case of a normal rectangular paddle blade. Since the shortest distance from any point on the lower edge of the paddle blade to the tank bottom is substantially constant, that is, the clearance between the blade and the tank bottom is substantially constant, the reaction liquid at the bottom of the tank is disturbed by the rotation of the paddle blade. It is eliminated toward the tank wall without waking up. Further, since the upper edge of the paddle blade has a shape that descends from the stirring shaft side end toward the tank wall side end, the reaction liquid removed toward the tank wall is less likely to be caught in the paddle blade again. Most of them are neatly discharged upward along the wall surface. As a result, the bottom of the reaction vessel and the vicinity of the wall surface are in a steady flow. As a result, scale generation accompanying the progress of the slurry polymerization reaction can be prevented.
[0020]
The “lowermost part” of the stirring shaft is a stirring blade mounting position in which no other stirring blade is mounted below it, and the minimum clearance between the stirring blade and the tank bottom is 1 to 5 cm, The paddle blade mounting position is preferably 2 to 5 cm.
The shortest distance from the lower edge of the wing to the bottom of the tank is “substantially constant”. The ratio of the minimum value to the maximum value of the shortest distance is usually 0.7 to 1, preferably 0.8 to 1. Means that. If this ratio is too small, the paddle blade may cause turbulence.
The degree to which the upper edge of the paddle blade “falls” toward the end on the tank wall side is usually determined by the angle formed by the upper edge of the paddle blade and the horizontal line on the projection surface where the paddle blade is projected onto the plane including the stirring shaft. 2 to 20 degrees, preferably 5 to 15 degrees. If this angle is too small, turbulence may be formed and the scale may adhere to the wall or the stirring blade. If this angle is too large, the stirring effect of the paddle blade may be reduced. The upper edge does not necessarily have to be a single linear shape, and may be a curved shape, a shape in which a straight line and a curve are combined, or a shape composed of a plurality of straight lines. The angle formed by “lowering” when the upper edge is not a single straight line is an imaginary line connecting the stirring shaft side end and the tank wall side end of the upper edge of the blade on the projection plane. Refers to the angle between and the horizontal direction.
[0021]
The diameter d of the paddle blade is such that the ratio d / D to the inner diameter D of the reaction vessel is usually 0.3 to 0.8, preferably 0.5 to 0.7. The maximum width (distance between the upper edge and the lower edge of the end on the stirring shaft side) h of the paddle blade is such that the ratio h / H to the internal method H between the top and bottom of the reaction tank is usually 0.1 to 0. .3, preferably a length of 0.1 to 0.2.
[0022]
The stirring power required for the paddle blade is usually 0.005 to 0.5 kw / m.³, Preferably 0.05 to 0.1 kw / m³It is. Here, the power required for stirring is the total stirring power required for the rotation of the stirring shaft during the polymerization reaction, excluding the rotational drive load required for the rotation of the stirring shaft in the empty reaction tank. The value obtained by dividing the net stirring power by the volume of the reaction solution layer.
[0023]
The material of the paddle blade is not particularly limited, but the same material as that of the reaction vessel is preferable, and stainless steel, stainless steel clad steel, glass lining steel and the like are preferable. Moreover, it is preferable that the surface is smooth.
Further, the presence / absence of baffles, the number of baffles, and the type of baffles are not particularly limited.
[0024]
Above the paddle blade attached to the lowermost part of the stirring shaft, further 1 to 5 stages of stirring blades may be attached to the stirring shaft according to the depth of the liquid layer. In that case, it is preferable that the stirring blade mounted on the upper side has a horizontal projection area and a vertical projection area each having a size smaller than that of the lowest paddle blade. Further, the shape of the stirring blade mounted on the upper side may be a paddle blade having the same shape as the lowermost blade, or another type of stirring blade. Other types of stirring blades include paddles (rectangular blades), turbines, disk turbines, marine, bull margins, and the like. In addition, an inclined paddle in which the wing is inclined upward, a deformable bull margin in which the blade is inclined upward and in the rotational direction, and the like can be used.
[0025]
The paddle blade used in the method of the present invention is preferably a swept blade. A swept wing means that the tip of the wing (end on the tank wall side) is more in the direction of rotation than on the straight line extending from the base end of the wing (end on the stirring shaft side) in the vertical direction with respect to the stirring shaft. It is a stirring blade in a rearward position.
In the present invention, in the plan view of the stirring blade as viewed from above the stirring shaft, the degree of retreat is a straight line connecting the center of the stirring shaft and the tip of the blade, and a tangent in the rotational direction forward of the end of the blade on the stirring shaft side. It is expressed as an angle formed by (retreating degree). By providing the paddle blade with a retreating degree, it is possible to increase the amount of liquid removed by the rotation of the paddle blade, and to increase the ratio of the amount of liquid that rises with respect to the amount of liquid that is involved. The degree of retreat is usually 0 to 70 degrees, preferably 30 to 60 degrees. If the degree of retreat is too large, the effect of increasing the discharge flow rate may be reduced.
When the paddle blade used in the method of the present invention is a swept blade, when the cross section of each blade is viewed as a thick line in the plan view of the stirring blade viewed from above the stirring shaft, the shape is a straight line, a curve, or a straight line and a curve Any of these composites may be used. When the shape of the swept wing is a straight line, it becomes a polygonal line shape in which at least two straight lines are combined.
The shape of the reaction vessel used in the present invention is not particularly limited, but it is preferably a vertical cylindrical shape generally used for polymer polymerization reaction.
[0026]
Next, a stirring blade used in the method of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view of a reaction vessel equipped with a stirring blade of one embodiment used in the method of the present invention. 2 (a) is a plan view of the stirring blade of the embodiment of FIG. 1, FIG. 2 (b) is a plan view of the stirring blade of another embodiment used in the method of the present invention, and FIG. 2 (c) is still another embodiment. It is a top view of the stirring blade of an aspect.
In FIG. 1, a paddle blade 2 is attached to the lowermost portion of the stirring shaft 1, and the shortest distance from an arbitrary point on the lower edge 4 of the paddle blade 2 to the tank bottom 6 of the reaction tank 5 is substantially constant. The upper edge 7 of the paddle blade 2 has a shape that descends from the end 8 on the stirring shaft side toward the end 9 on the tank wall side. The lowering degree of the upper edge 7 is a curved shape that monotonously decreases (convex downward) as it goes toward the tank wall. (A convex shape), a linear shape with a constant degree of descent, or a composite shape thereof. In FIG. 1, the angle θ formed by the imaginary line connecting the end on the stirring shaft side of the upper edge 7 and the end on the tank wall side with the horizontal direction on the plane including the stirring shaft is in the range of 2 to 20 degrees. is there.
[0027]
In the embodiment shown in FIG. 1, a further stirrer blade 3 is mounted above the paddle blade 2, but the number of stirrer blades further mounted above is a plurality of stages depending on the depth of the reaction liquid. It can be used or not mounted. In addition, in the embodiment shown in FIG. 1, the stirring blade mounted on the upper side is a paddle blade having a normal rectangular blade, but an arbitrary shape such as a turbine, a disk turbine, an inclined paddle, or a marine is adopted. Can do.
[0028]
FIG. 2A is a plan view of the paddle blade 2 of the aspect shown in FIG. 1 as viewed from above the stirring shaft. This paddle wing is not a swept wing. FIG. 2B is a plan view of the paddle retracting blade curved in a curved shape, and FIG. 2C is a plan view of the paddle retracting blade formed by bending a flat plate and having two straight lines combined on the plan view. FIG.
The retreating degree in FIG. 2B is an angle α formed by a straight line connecting the center of the stirring shaft and the tip of the blade on the plan view and a tangential line in the rotational direction forward of the end of the blade on the stirring shaft side.
The receding degree in FIG. 2 (c) is the straight line connecting the center of the stirring shaft and the end of the blade on the tank wall side, and the tangent line in the rotational direction forward of the end of the blade on the stirring shaft side, that is, of the two straight lines. An angle β formed with the straight line on the stirring shaft side.
The receding degrees α and β are both in the range of 2 to 70 degrees.
[0029]
By using the above paddle blade, slurry polymerization of oxirane monomer at 30-100 ° C. in the presence of a catalyst in the organic solvent of the reaction tank is carried out, so that the polyether polymer is hardly attached to the reaction tank. A slurry can be obtained.
Furthermore, as a slurry polymerization method, a step (A) of forming a polyether polymer seed in the polymerization reaction step, and a polyether obtained by polymerizing an oxirane monomer in the presence of the obtained polyether polymer seed By adopting the method using the paddle blade in at least the step (B), which has a step (B) for forming a polymer slurry, it is possible to further reduce scale adhesion in the reaction vessel.
That is, in the polymerization reaction of the step (A), a polymerization liquid (seed slurry) containing a polyether polymer seed that becomes a nucleus for subsequent polymer particle formation using a part of the monomer and a part of the catalyst in advance. A two-stage polymerization method in which the remaining catalyst and monomer are charged in the polymerization reaction of step (B) and the seed is coated and polymerized is employed, and at least in step (B), the paddle blade is used. is there. The stirring blade in the step (A) is not particularly limited, and the paddle blade may be used. In the step (B), it is preferable that the catalyst and the monomer are charged continuously or intermittently with the progress of the polymerization conversion rate, rather than charging all at once.
The seed slurry preparation in the step (A) and the coating polymerization in the step (B) can be performed according to the method described in Patent Document 1.
[0030]
Among the two-stage polymerization methods, the step (A) and the step (B) are performed in separate reaction vessels, and the seed slurry obtained in the step (A) is received in the reaction vessel for performing the step (B) before the reaction. It is preferable to wet the inside of the tank, that is, the inner wall of the reaction tank or the surface of the stirring blade with an organic solvent used for slurry polymerization in advance because scale adhesion can be further reduced. When a layer wetted with a solvent is present on the inner wall of the reaction vessel or the stirring blade surface in which the step (B) is performed, the seed slurry received is prevented from being strongly adsorbed on the surface, and the scale buds are picked up. Occurrence can be prevented.
[0031]
By the above method, slurry polymerization of the oxirane monomer is carried out in the presence of a catalyst in the organic solvent using the paddle blade to obtain a polymer slurry, and then the organic solvent is usually removed to produce a polyether polymer. . The removal of the organic solvent is based on a method in which the polymer slurry is filtered with a filter medium such as a wire mesh, and the polyether polymer particles dispersed in the slurry are recovered and maintained in a heated and / or reduced pressure state. Is preferred. When the polymer is recovered in the form of particles, it is preferably dried under reduced pressure at a temperature of 30 to 45 ° C. If the temperature is too low, the solvent is difficult to evaporate, and if the temperature is too high, the polymer particles may be fused to form a lump.
[0032]
The polyether polymer obtained by the method of the present invention can be suitably used as a polymer solid electrolyte film used in batteries (cathode film or ion conductive electrolyte film), capacitors, capacitors and the like.
In order to produce a solid polymer electrolyte film, a composition is prepared by blending a polyether polymer with an electrolyte salt compound soluble in the polymer prior to molding.
The electrolyte salt compound is not particularly limited as long as it is a compound that can move a cation and is soluble in the polyether polymer used in the present invention. Specific examples of such electrolyte salt compounds include halogen ions, perchlorate ions, thiocyanate ions, trifluoromethanesulfonate ions [CF₃SO₃ ⁻], Bis (trifluoromethanesulfonyl) imide ion [N (CF₃SO₂)₂ ⁻], Bis (heptafluoropropylsulfonyl) imide ion [N (C₂F₅SO₂)₂ ⁻], Trifluorosulfonimide ion, tetrafluoroborate ion [BF₄ ⁻], Nitrate ion, AsF₆ ⁻, PF₆ ⁻And a salt formed of an anion such as stearyl sulfonate ion and octyl sulfonate ion and a metal cation such as lithium, sodium, potassium, rubidium, and cesium. Especially, when used as a solid electrolyte of a lithium polymer battery, LiBF₄, LiPF₆, LiCF₃SO₃, LiN (CF₃SO₂)₂, LiN (C₂F₅SO₂)₂Is more preferable.
[0033]
The amount of the electrolyte salt compound used relative to the polyether polymer is usually 0.001-5, preferably 0.005-3, (number of moles of electrolyte salt compound) / (total number of moles of ether oxygen in the copolymer). More preferably, the amount is 0.01 to 1. If the amount of the electrolyte salt compound used is too large, the molding processability and the mechanical strength and ion conductivity of the obtained polymer solid electrolyte film may be lowered. On the other hand, if the amount of the electrolyte salt compound is too small, the ionic conductivity of the polymer solid electrolyte film is lowered.
[0034]
When using a polymer electrolyte film as a cathode film of a battery, in addition to the electrolyte salt compound, an active material such as particulate lithium cobaltate or lithium manganese composite oxide in addition to the electrolyte salt compound, A conductive material such as acetylene black or ketjen black is blended.
Moreover, when using a polymer solid electrolyte film as an ion conductive electrolyte film of a battery, it is preferable to bridge | crosslink a polyether polymer composition, In that case, a crosslinking agent is also mix | blended with a polyether polymer composition. For crosslinking, a polyether polymer composition containing a radical initiator, a crosslinking agent for thermal crosslinking such as sulfur or mercaptotriazine, or a photocrosslinking agent such as benzyldimethyl ketal, trimethylsilylbenzophenone or benzoin is heated after molding or simultaneously with molding. Alternatively, it is carried out by irradiation with actinic radiation.
[0035]
As a method for forming a polymer solid electrolyte film, there are an extrusion method and a cast method, but an extrusion method is preferable from the viewpoint of productivity and safety and health.
In the extrusion molding method, a polyether polymer composition is prepared by previously mixing a compounding agent such as a polyether polymer and an electrolyte salt compound with a mixing roll, a Banbury mixer, a kneader or a Brabender, and the like. Is formed into a film by extrusion with an extruder. Or you may extrude, mixing a part of compounding agent in a molding machine barrel in the case of extrusion molding.
In the cast molding method, a polyether polymer composition prepared by adding a compounding agent to the polymer slurry after the polymerization reaction is cast into a flat shape, and the organic solvent is volatilized by heating and decompression to form a film.
The thickness of the polymer solid electrolyte film thus obtained is usually 10 to 150 μm, preferably 20 to 100 μm. If the thickness is too thin, the production stability may be lacking. Conversely, if the thickness is too thick, the ionic conductivity may be lowered.
[0036]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In the following, “part” and “%” are based on weight unless otherwise specified.
Examples and Comparative Examples were performed based on the following apparatus conditions and catalyst preparation.
(1) Reaction tank
As a reaction vessel for the polymerization reaction, two stainless steel bottom bowl-shaped cylindrical containers having the specifications described below were used.
・ Inner diameter 200mm, inner space 315mm, straight barrel wall height 260mm
・ With warm water jacket for temperature control
・ Equip the upper lid with a nozzle for deaeration and nitrogen injection, a seed slurry receiving nozzle, a solvent charging nozzle, and a monomer charging nozzle.
-At the center of the lid, a hydraulic screw seal unit equipped with a reverse screw socket that can be attached and detached on the inner side of the reaction tank and an electric pulley shaft on the outer side of the reaction tank.
[0037]
(2) Stirring blade
3 to 7 show the stirring blades used in the examples and comparative examples. 3 is a paddle wing according to the method of the present invention, FIG. 4 is a paddle wing with a receding degree of 20 degrees according to the method of the present invention, FIG. 5 is a paddle wing (normal rectangular wing), FIG. 6 is a modified bull margin wing, and FIG. Max blend wings, both made of stainless steel with a thickness of 3 mm. The stirring blade shown in FIG. 6 has three blades opened at intervals of 120 degrees around the stirring shaft, and the other stirring blades are two blades opened at intervals of 180 degrees.
The shortest distance from any point on the lower edge of the stirring blade shown in FIGS. 3 and 4 to the bottom of the tank is almost constant at 20 ± 2 mm for any stirring blade, and the upper edge of the stirring blade is horizontal for all stirring blades. The angle formed with the direction has a shape that linearly descends toward the tank wall side at 15 degrees on the projection surface onto the plane including the stirring shaft. Moreover, all the stirring blades have d / D of 0.6 and h / H of 0.17.
In the paddle wing shown in FIG. 5, the shortest distance between an arbitrary point on the lower edge of the wing and the tank bottom is not constant, and the line of the upper edge of the wing is horizontal.
The deformable bull margin wing shown in FIG. 6 has three rectangular plates with a width of 55 mm and a length of 25 mm, each of which is vertically oriented with its longitudinal direction on its side. This is a shape that is raised 30 degrees upward while facing the end of 40 degrees inward.
[0038]
(3) Preparation of polymerization catalyst solution used in Examples and Comparative Examples
Pour 159.7 g of triisobutylaluminum, 1170 g of toluene, and 296.4 g of diethyl ether in a 3 liter stainless steel autoclave with a marine stirrer that has been purged with nitrogen and dried.₂O_Five23.5 g of phosphoric acid having a content of 72.4% by weight or more was gradually added. To this, 12.1 g of triethylamine was added and aged at 60 ° C. for 2 hours to obtain a polymerization catalyst solution.
[0039]
Example 1
The first reaction vessel equipped with the stirring blade shown in FIG. 6 was purged with nitrogen and degassed, and 2100 g of normal hexane and 164.2 g of the polymerization catalyst solution were added and kept at 35 ° C. while stirring. This was charged with 7.9 g of a mixed solution of ethylene oxide / propylene oxide = 36.1 / 63.9 in a molar ratio and polymerized at 30 to 35 ° C. while stirring at 250 rpm to obtain a seed slurry.
Next, the second reaction vessel equipped with the stirring blade shown in FIG. 3 was dried and purged with nitrogen, then 6500 g of normal hexane was injected, and immediately extracted from the bottom valve, the whole amount of the seed slurry was received, 2100 g of normal hexane was added. Power required for stirring 0.012kW / m³, 1050 g of a mixed solution of ethylene oxide / propylene oxide = 89.8 / 10.2 in a molar ratio was continuously added over 5 hours, and the polymerization temperature was controlled at 60 ° C.
The polymerization reaction was terminated by cooling at a conversion rate of 95% to obtain a slurry of a particulate polymer having an average particle size of 430 μm. When the can was opened and observed, no scale was seen on the inner wall of the reaction vessel and the stirring blade, but when the inside of the vessel was dried and observed again, a slightly whitish cloudy scale was seen on the inner wall and the stirring shaft. There were no manufacturing problems.
The scale amount was 0.3% with respect to the charged monomer on a dry basis. In addition, the baffle was not used for the 1st and 2nd reaction tank.
[0040]
Example 2
In Example 1, the power required for stirring was 0.01 kW / m using the stirring blade shown in FIG. 4 as the stirring blade of the second reaction tank.³The stirring was carried out in the same manner as in Example 1, and the polymerization reaction was completed by cooling at a conversion rate of 96% to obtain a slurry of a particulate polymer having an average particle size of 380 μm. When it was opened and observed, no scale was observed on the inner wall of the reaction vessel and the stirring blade. No scale was seen after drying the tank.
[0041]
Comparative Example 1
In Example 1, the power required for stirring was 0.02 kW / m using the stirring blade shown in FIG. 5 as the stirring blade of the second reaction tank.³The reaction was conducted in the same manner as in Example 1 except that the polymerization reaction was completed by cooling at a conversion rate of 95% to obtain a slurry of a particulate polymer having an average particle size of 560 μm. When the container was opened and observed, the scale adhered to the wall surface, the stirring shaft, and the entire stirring blade, and the scale amount was 3.3% based on the amount of charged monomer on a dry basis.
[0042]
Comparative Example 2
In Example 1, the power required for stirring was 0.12 kW / m using the stirring blade shown in FIG. 6 as the stirring blade of the second reaction tank.³The stirring was carried out in the same manner as in Example 1, and the polymerization reaction was completed by cooling at a conversion rate of 97% to obtain a slurry of a particulate polymer having an average particle size of 610 μm. When the can was opened and observed, the scale adhered to the wall surface, the stirring shaft, and the tip of the stirring blade, and the scale amount was 5.3% based on the dry monomer.
[0043]
Comparative Example 3
In Example 1, the required power for stirring 0.015 kW / m using the stirring blade shown in FIG. 7 as the stirring blade of the second reaction tank³The reaction was conducted in the same manner as in Example 1, except that the polymerization reaction was completed by cooling at a conversion rate of 95% to obtain a slurry of a particulate polymer having an average particle diameter of 400 μm. When the container was opened and observed, the scale adhered to the wall surface, the stirring shaft, and the bottom paddle part of the stirring blade, and the scale amount was 1.2% based on the charged monomer on a dry basis.
[0044]
【The invention's effect】
According to the method of the present invention, the polymerization of the oxirane monomer by the slurry polymerization method can be performed without adhesion of the scale in the polymerization reaction tank, so that a stable quality polyether polymer can be produced with high productivity. . In addition, since the polyether polymer produced by the method of the present invention does not contain hard coarse particles due to the scale, when it is used for extrusion molding, the light weight is stable, the film has a uniform thickness and a smooth surface. Is obtained. And since the solid electrolyte using this film shows the outstanding mechanical strength and ion conductivity, it is suitable as a solid electrolyte for polymer batteries, especially for lithium batteries.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of a reaction vessel equipped with a paddle blade of one embodiment used in the method of the present invention.
2 (a) is a plan view of a paddle blade of the embodiment of FIG. 1, FIG. 2 (b) is a plan view of a paddle blade of another embodiment used in the method of the present invention, and FIG. It is a top view of the paddle wing of other embodiments.
FIG. 3 (a) is an explanatory view of a paddle blade according to the method of the present invention attached to the second reaction tank of Example 1, and FIG. 3 (b) is a plan view of the stirring blade. The unit of the numerical values in the figure is mm.
4 (a) is an explanatory view of a paddle blade having a retreat degree according to the method of the present invention attached to the second reaction tank of Example 2, and FIG. 4 (b) is a plan view of the stirring blade. It is. The unit of the numerical values in the figure is mm.
5A is an explanatory view of a normal paddle blade attached to the second reaction tank of Comparative Example 1, and FIG. 5B is a plan view of the stirring blade. The unit of the numerical values in the figure is mm.
FIG. 6 (a) is a modified bull margin attached to the autoclave and the first reaction tank for preparing the polymerization catalyst solution and attached to the second reaction tank of Comparative Example 2 in Examples and Comparative Examples. FIG. 6B is a plan view of the stirring blade. The unit of the numerical values in the figure is mm.
FIG. 7 (a) is an explanatory view of a Max Blend blade installed in the second reaction tank of Comparative Example 3, and FIG. 7 (b) is a plan view of the same stirring blade. The unit of the numerical values in the figure is mm.
[Explanation of symbols]
1 Stirring shaft
2 Paddle blades used in the method of the present invention
4 Lower edge
5 reaction tank
6 Tank bottom
7 Upper edge

Claims (4)

A method for producing a polyether polymer in which an oxirane monomer is slurry-polymerized in an organic solvent in the presence of a catalyst,
In the first reaction tank, a step (A) of forming a polyether polymer seed using a part of the oxirane monomer, and the second reaction layer is charged with the remaining oxirane monomer, and the second reaction in the bath, it has a step in the presence of a polyether polymer seed obtained by (a) an oxirane monomer of the remainder is slurry polymerized to form a polyether polymer slurry (B),
In the step (B), as a stirring blade attached at least to the lowermost part of the stirring shaft, the shortest distance from any point on the lower edge of the blade to the bottom of the tank is substantially constant, and the upper edge of the blade is on the stirring shaft side Using a paddle blade having a shape descending from the end of the tank toward the end on the tank wall side,
Prior to receiving the reaction liquid containing the polyether polymer seed obtained in the step (A) in the second reaction tank for performing the step (B), the inside of the second reaction tank is an organic solvent used for slurry polymerization. A method for producing a polyether polymer, which comprises wetting.   2. The method for producing a polyether polymer according to claim 1, wherein an angle formed by the upper edge of the paddle blade with the horizontal direction is 2 to 20 degrees in a projection plane onto a plane including the stirring shaft.   The method for producing a polyether polymer according to claim 1 or 2, wherein the paddle blade has a receding degree of 2 to 70 degrees. The method for producing a polyether polymer according to any one of claims 1 to ³ , wherein the power required for stirring the paddle blade is 0.005 to 0.5 kW / m ³ .

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