JP4828130B2 - Method for producing a membrane for ion exchange membrane - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a method for producing an ion exchange membrane original membrane that is used for ion exchange membranes by introducing ion exchange groups, and more particularly, a core film is coated or impregnated with a polymerizable paste. It is related with the method of manufacturing the raw film for ion-exchange membranes by superposing | polymerizing in the state in which the polymeric film produced by doing is wound by the winding roller.

Conventionally, a so-called paste method is known as a method for producing an ion exchange membrane. In this method, a base sheet having a function as a reinforcing material is coated or impregnated with a polymerizable paste to produce a polymerizable sheet having a base sheet inside a layer made of the polymerizable paste. By polymerizing the polymerizable paste to produce a raw film (ion exchange membrane raw film) to be used for introduction of ion exchange groups, by introducing various ion exchange groups into this raw film, It is to manufacture (refer patent document 1).
Shoko 39-27861 Japanese Patent No. 3193522

  By the way, in the actual production process, in many cases, the original film used for introducing the ion exchange group is formed by applying or impregnating a base material sheet with a polymerizable paste to form a polymerizable sheet. While a release film such as a polyethylene terephthalate (PET) film is attached to one surface of the film, the polymerizable sheet is wound up in the form of a laminate with the release film, and is thus wound around a winding roller. It is manufactured by polymerizing a polymerizable paste in the state. This is because this method is suitable for continuous production and can efficiently produce a raw film.

  However, in the case of producing a raw film by polymerizing a polymerizable paste while the polymerizable sheet is wound on a winding roller, in order to further increase the production efficiency, the number of windings of the polymerizable sheet by the winding roller is increased. However, if the number of turns is increased, the polymerization does not proceed uniformly, wrinkles occur in the original film, or the base sheet is partially deteriorated, and the strength of the original film is partially increased. The actual condition is that the number of windings of the polymerizable sheet is limited.

  Therefore, the object of the present invention is to increase the number of windings of the polymerizable sheet by the winding roller and to polymerize the polymerizable paste in the rolled-up polymerizable sheet, thereby achieving high productivity for an ion exchange membrane. It is an object of the present invention to provide a method for producing an original film without causing deterioration in quality.

According to the present invention, a polymerizable sheet in which a base sheet is embedded in a layer made of a polymerizable paste containing a polymerizable monomer and a polymerization initiator is attached, and a release film is attached to one surface thereof. A film for ion exchange membrane is obtained by polymerizing the polymerizable paste in a state in which a polymerizable sheet with a releasable film attached thereto is wound around a winding roller while being continuously wound by a winding roller. In the method of manufacturing
The polymerization of the polymerizable paste is performed with the total thickness of the polymerizable sheet on the winding roller being 10 mm or more, and the polymerization is performed by gradually increasing the polymerization temperature in multiple stages. Is carried out at a polymerization temperature that is 3 to 15 ° C. lower than the 10-hour half-life temperature of the polymerization initiator, and the second and subsequent polymerizations are carried out at a polymerization temperature that is 10 to 50 ° C. higher than the polymerization temperature of the first stage. There is provided a method for producing an ion exchange membrane original membrane characterized in that it is performed .

In the production method of the present invention, in general,
(1) The polymerization in the first stage is performed for 4 to 12 hours, and the polymerization in the second stage and thereafter is performed for 0.5 to 5 hours.
(2) The outer diameter of the winding roller is 0.1 m or more,
(3) The thickness of the base sheet is in the range of 10 to 500 μm, and the thickness of the polymerizable sheet is in the range of 10 to 1000 μm.
Is preferred.

In the present invention, polymerization is performed in a state where the polymerizable sheet is wound on a winding roller until the total thickness of the polymerizable sheet becomes 10 mm or more, and the production efficiency is increased by increasing the number of windings of the polymerizable sheet. However, what is particularly important is that the polymerization of the polymerizable sheet (polymerizable paste) is performed in multiple stages. The polymerization in the first stage is 3 to 15 ° C. lower than the 10-hour half-life temperature of the polymerization initiator. The polymerization is performed at a temperature, and the second and subsequent polymerizations are performed at a polymerization temperature 10 to 50 ° C. higher than the polymerization temperature of the first stage.

  That is, when a release film is attached to the polymerizable sheet and wound with a winding roller, the winding is performed so that the total thickness of the polymerizable sheet (that is, excluding the thickness of the release film) is 10 mm or more. When the polymerizable paste in such a polymerizable sheet is polymerized, there is a large gap between a portion located inside the polymerizable sheet (winding roller surface side) and a portion located on the outer surface side. It is considered that a temperature difference occurs, and as a result, the quality of the obtained original film is degraded. That is, in the portion located on the outer surface side, the polymerization heat is easily dissipated into the atmosphere, but in the portion located in the inside, the releasable film is interposed therebetween, so that the polymerization heat is external. As a result, the portion located inside the polymerizable sheet becomes considerably hotter than the portion located on the outer surface side. For this reason, wrinkles are generated in the obtained original film, particularly in the interior located on the surface side of the take-up roller, or the strength is reduced due to deterioration of the base material sheet, resulting in variations in physical properties. .

  However, in the present invention, the polymerization is performed in multiple stages of the first stage polymerization in the low temperature region and the second and subsequent polymerizations in the high temperature region as described above. When the total thickness was increased to 10 mm or more, it became possible to produce a raw film without causing quality degradation. That is, since the first stage polymerization is carried out in a low temperature region that is 3 to 15 ° C. lower than the 10-hour half-life temperature, the polymerization gradually proceeds and the generation of polymerization heat is suppressed. The subsequent polymerization in the second and subsequent stages is carried out in a high temperature region 10 to 50 ° C. higher than the polymerization temperature in the first stage, but the polymerization has already progressed to a certain molecular weight by the first stage polymerization. Therefore, no large polymerization heat is generated, and the polymerization is performed to the final polymer with the suppressed polymerization heat. Therefore, in the present invention, the number of windings of the polymerizable sheet is increased so that the total thickness becomes 10 mm or more, and it is possible to efficiently manufacture the original film without causing quality deterioration. .

  In the present invention, by performing the polymerization in two or three or more stages as described above, for example, the total thickness of the polymerizable sheet wound on the take-up roller can be increased by 10 mm or more at the maximum.

The present invention will be described below based on specific examples shown in the accompanying drawings.
FIG. 1 is a diagram showing a production and winding process of a polymerizable sheet carried out in the present invention,
FIG. 2 is a view showing the layer structure of the polymerizable sheet obtained in the step of FIG. 1 together with the release film.

  With reference to FIG. 1, in the production and winding process of the polymerizable film, the substrate roller 3 around which the substrate sheet 1 is wound, the coating tank 7 filled with the polymerizable paste 5, the winding roller 9, and A release material roller 13 around which the release film 11 is wound is disposed.

  The substrate sheet 1 is wound up from the substrate roller 3 by a winding roller 9 via a plurality of tension rollers 15, and is immersed in the polymerizable paste 5 in the coating tank 7 in the middle thereof. Thus, by forming a layer of the polymerizable paste 5 having the base sheet 1 inside, a polymerizable sheet indicated by 20 as a whole is produced.

  The releasable film 11 is wound on the core film 1 by the take-up roller 9 from the release material roller 13 through the plurality of tension rollers 21. The release film 11 is attached to one surface of the polymerizable film 20 by the attaching roller 23 arranged at a position facing the substrate 9 and elastically biased, and laminated with the release film 11. In this form, the polymerizable sheet 20 is wound around the winding roller 9.

  As shown in FIG. 2, the polymerizable sheet 20 thus produced is composed of a layer of the polymerizable paste 5 having the base sheet 1 inside, and on one surface thereof, the release sheet is formed. The adhesive film 11 is affixed.

  In the present invention, it is important to wind up the polymerizable sheet 20 by the winding roller 9 so that the total thickness (thickness excluding the release film 11) is 10 mm or more, particularly 20 mm or more. . That is, in the present invention, by increasing the number of windings of the polymerizable sheet 20 on the take-up roller 9, the long polymerizable sheet 20 is produced at a time, and the production efficiency is increased. Incidentally, when the number of windings of the polymerizable sheet 20 increases and the total thickness of the polymerizable sheet 20 on the take-up roller 9 exceeds 10 mm, temperature unevenness easily occurs during polymerization, which will be described later. Although deterioration of the quality of the original film occurs, such quality deterioration can be avoided by performing polymerization of the polymerizable paste in two stages or more.

<Base material sheet 1>
In the present invention, as the base sheet 1, those conventionally used as a base material for reinforcing ion exchange membranes are used without any limitation. For example, polyvinyl chloride, polyethylene, polypropylene, polybutene or these as materials Polyolefins such as copolymers or blends of the above are used, but polyolefin base sheets are particularly preferred from the standpoint of durability of the ion exchange membrane finally produced.

  Although the base material sheet 1 has the form of a woven fabric normally, it may have forms, such as a nonwoven fabric, a net | network, and a porous sheet. The single yarn of the woven fabric may be either a monofilament or a multifilament. Furthermore, although the electrical resistance of the ion exchange membrane which can be obtained when the basis weight of the warp yarn or weft yarn in the base material sheet 1 is smaller can be reduced, in general, in order to suppress a decrease in form retention due to yarn slippage, generally 1 square inch. It is preferable that the number of hits is set in a range of about 10 to 500. In addition, if a device such as partial fusion of the intersections of single yarns is used, a woven fabric having a mesh number of 10 or less can be used as a base sheet, for example, a composite in which the core portion is polypropylene and the sheath portion is polyethylene. If filaments are used and the polyethylene part at the intersection is fused, a woven fabric having a small number of meshes can be used as the base sheet 1. Although the thickness of such a base material sheet 1 is not specifically limited, Usually, it exists in the range of 10-500 micrometers.

  The base sheet 1 made of polyolefin is calendered to improve the surface smoothness of the base sheet 1 by compressing the intersection of the warp and weft yarns, or by heat-treating the base sheet 1 in advance. The dimensional change of the base sheet 1 in the polymerization step described later can also be suppressed. Furthermore, well-known surface treatments, such as a corona discharge process and a chlorosulfonic acid process, can be performed and the adhesiveness of the base sheet 1 and the ion exchange resin part derived from the polymeric paste mentioned above can also be improved.

<Polymerizable paste 5>
The polymerizable paste 5 applied to the base sheet 1 forms a resin into which an ion exchange group is introduced, and includes at least a polymerizable monomer and a polymerization initiator. It contains a matrix resin that does not contribute to the introduction of exchange groups, and further contains a crosslinking agent if necessary.

  As the polymerizable monomer, a known monomer used for the formation of an ion exchange resin is used without any limitation. For example, a monomer having a functional group suitable for introduction of an ion exchange group or an ion exchange A monomer having a group as a functional group is used. Examples of the monomer having such a functional group include styrene, vinyl toluene, vinyl xylene, α-methyl styrene, acenaphthylene, vinyl naphthalene, α-halogenated styrene, α, β, β′-trihalogenated styrene, chloro. Styrene and the like are typical, but particularly when the original membrane is used for forming a cation exchange membrane, α-halogenated vinyl sulfonic acid, α, β, β′-halogenated vinyl sulfonic acid, methacrylic acid, Acrylic acid, styrene sulfonic acid, vinyl sulfonic acid, maleic acid, itaconic acid, styrene phosphonylic acid, maleic anhydride, vinyl phosphoric acid, and salts and esters thereof are suitable. When used for formation, vinyl pyridine, methyl vinyl pyridine, ethyl vinyl pyridine, vinyl pyrrolidone, vinyl Carbazole, vinyl imidazole, aminostyrene, alkylaminostyrene, dialkylaminostyrene, trialkylaminostyrene, methyl vinyl ketone, chloromethyl styrene, acrylic amide, acrylamide, oxynium, styrene, vinyl toluene, etc. are suitable. A monomer may be used individually by 1 type, or can also be used in combination of 2 or more type mutually copolymerizable.

  Moreover, as said monomer, what can be copolymerized with the crosslinking agent mentioned later is contained, or you may contain as a comonomer. Monomers copolymerizable with such crosslinking agents include styrene, acrylonitrile, ethyl styrene, vinyl chloride, acrolein, methyl vinyl ketone, maleic anhydride, maleic acid, maleic acid salts or esters, itaconic acid, Examples thereof include salts or esters of itaconic acid.

  The polymerization initiator used together with the above-described monomer is appropriately selected according to the type of the base sheet 1.

  For example, when the base sheet 1 made of polyvinyl chloride is used, a radical polymerization initiator having a 10-hour half-life temperature of 110 ° C. or less, specifically, benzoyl peroxide, methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide Oxide, cyclohexane peroxide, methylcyclohexane peroxide, isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, o-methylbenzoyl peroxide, bis-3,5,5-trimethylhexanoyl peroxide, lauroyl peroxide, p -Chlorobenzoyl peroxide, 1,1-di-tert-butylperoxy-trimethylcyclohexane, 1,1-di-tert-butylperoxy-cyclohexane, 2,2-di- (tert-butylperoxy) -butane 4,4-di-tert-butyl Peroxyvaleric acid-n-butyl ester, 2,4,4-trimethylpentylperoxy-phenoxyacetate, α-cumylperoxyneodecanoate, tert-butylperoxyneodecanoate, tert-butylperoxybiba Tert-butylperoxy-2-ethylhexanoate, tert-butylperoxy-isobutyrate, di-tert-butylperoxy-hexahydroterephthalate, di-tert-butylperoxyazelate, tert-butylperoxy -3,5,5-trimethylhexanoate, tert-butyl peroxyacetate, tert-butyl peroxybenzoate and the like are used.

  When the polyolefin base sheet 1 is used, a radical polymerization initiator having a 10-hour half-life temperature of 110 ° C. to 170 ° C., specifically, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide Α, α′-bis (tert-butylperoxy-m-isopropyl) benzene, di-tert-butyl peroxide, tert-butyl hydroperoxide, di-tert-amyl peroxide, tert-butyl cumyl peroxide, Dicumyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3, cumene hydroper Oxide, 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethyl-2,5-dihydroperoxyhexa And 2,5-dimethyl-2,5-dihydro peroxy f relaxin-3 used.

  The polymerization initiator is usually used in an amount of 2 to 15 parts by weight per 100 parts by weight of the polymerizable monomer, and particularly 2 to 4.5 parts by weight in terms of reducing polymerization heat. It is optimal to use the polymerization initiator in a relatively small amount. That is, by setting the blending amount of the polymerization initiator to be small, it is advantageous for suppressing the temperature rise of the polymerizable sheet 20 at the time of polymerization and suppressing the deterioration of the quality of the original film obtained from the polymerizable sheet 20. It becomes.

  The cross-linking agent used in combination with the above-described polymerizable monomer and polymerization initiator as necessary is used to increase the strength of the film and the like. As such a cross-linking agent, m-, p -Or divinyl compounds such as o-divinylbenzene, divinylsulfone, butadiene, chloroprene, isoprene, trivinylbenzene, divinylnaphthalene, diallylamine, triallylamine, and divinylpyridine can be exemplified. Such a crosslinking agent is generally used in an amount of 5 to 20 parts by weight per 100 parts by weight of the monomer.

  The polymerizable paste 5 preferably contains a matrix resin as a viscosity modifier. By adding such a matrix resin, the workability of the polymerizable paste 5 is improved, and this is used as a base material. It is possible to prevent dripping or the like when the sheet 1 is applied or impregnated, and to effectively wind the polymerizable sheet 20 by the winding roller 9.

  Examples of such a matrix resin include ethylene-propylene copolymer, saturated aliphatic hydrocarbon polymer such as polybutylene, styrene polymer such as styrene-butadiene copolymer, polyvinyl chloride, or vinyl. Styrene monomers such as toluene, vinyl xylene, chlorostyrene, chloromethyl styrene, α-methyl styrene, α-halogenated styrene, α, β, β'-trihalogenated styrene, monoolefins such as ethylene and butylene, Those obtained by copolymerizing conjugated diolefins such as butadiene and isoprene can be used. The molecular weight of such a matrix resin is usually in the range of 1,000 to 1,000,000, particularly 50,000 to 500,000, and the polymerizable paste 5 can be used in an amount sufficient to ensure an appropriate viscosity depending on the molecular weight. For example, the amount is about 2 to 30 parts by weight per 100 parts by weight of the polymerizable monomer.

  The polymerizable paste 5 may contain a plasticizer such as dioctyl phthalate, dibutyl phthalate, tributyl phosphate, styrene oxide, or an alcohol ester of a fatty acid or aromatic acid, or an organic solvent, if necessary. Good.

<Polymerizable sheet 20>
In the present invention, the base sheet 1 is polymerizable by immersing the base sheet 1 in the coating tank 7 in the polymerizable paste 5 in which the polymerization initiator amount is set in a predetermined range as described above. A polymerizable sheet 20 embedded in the layer of paste 5 is produced. Accordingly, the thickness of the polymerizable sheet 20 is thicker than that of the base sheet 1 and is usually in the range of about 10 to 500 μm.

<Releasable film 11>
In the present invention, the release sheet 11 is attached to one surface of the polymerizable sheet 20 formed by immersing the base sheet 1 in the polymerizable paste 5 in the coating tank 7, The film is wound around the winding roller 9 in the form of a laminate of the conductive film and the polymerizable sheet 20. That is, if the release film 11 is not attached, the polymerizable sheet 20 is integrated on the take-up roller 9 and the sheet shape is damaged.

  Such a releasable film 11 can be used without any limitation as long as it has heat resistance that can be endured in a polymerization step described later, and can be easily peeled off after polymerization, such as low-density polyethylene, High-density polyethylene, polypropylene, poly 1-butene, poly 4-methyl-1-pentene, or random or block copolymers of α-olefins such as ethylene, pyropyrene, 1-butene, 4-methyl-1-pentene, etc. Polyolefin, ethylene / vinyl acetate copolymer, ethylene / vinyl alcohol copolymer, ethylene / vinyl compound copolymer such as ethylene / vinyl chloride copolymer, polystyrene, acrylonitrile / styrene copolymer, ABS, α-methylstyrene・ Styrene resins such as styrene copolymers, polyvinyl chloride, polyvinyl chloride Ridene, vinyl chloride / vinylidene chloride copolymer, polyvinyl compounds such as polymethyl acrylate and polymethyl methacrylate, polyamides such as nylon 6, nylon 6-6, nylon 6-10, nylon 11 and nylon 12, polyethylene terephthalate, A material composed of a thermoplastic polyester such as polybutylene terephthalate or polyethylene naphthalate, polycarbonate, polyphenylene oxide or the like, a biodegradable resin such as polylactic acid, or a mixture thereof is used in the polymerizable paste 5. Polyester films such as polyethylene terephthalate (PET) are preferred, particularly in terms of good heat resistance and releasability, although such films can be used depending on the type of monomer and the like. It may be biaxially stretched. The thickness of the releasable film 11 is usually preferably in the range of about 50 to 200 μm. If it is too thick, not only will the production cost increase, but the heat of polymerization heat will not be effectively dissipated, and it will be easy to cause quality deterioration. End up.

<Winding roller 9>
The size of the take-up roller 9 used for winding the laminate of the polymerizable sheet 20 and the release film 11 is not particularly limited, but if it is too small, Since the number of windings must be remarkably increased and the total thickness of the polymerizable sheet 20 becomes remarkably thick, it is generally preferable that the outer diameter is 0.1 m or more, and 3 m or less, particularly 2 m. The following is preferable. Further, the take-up roller 9 is made of a metal material such as stainless steel, and the inside thereof is hollow for weight reduction (see FIG. 1). Furthermore, the winding roller 9 preferably has an appropriate heat capacity. For example, the heat capacity per 1 kg of the monomer present in the wound polymerizable sheet 20 is about 2 to 15 kJ / ° C. Thus, it is preferable that the thickness t of the winding roller 9 is set. That is, when the heat capacity of the take-up roller 9 is within this range, the heat of polymerization generated in the polymerizable sheet 20 is absorbed by appropriate heat transfer, and the abnormal temperature rise of the polymerizable sheet 20 due to the heat of polymerization is suppressed. be able to.

<Polymerization>
In the present invention, the polymerization is performed in a state where the polymerizable sheet 20 is wound until the total thickness becomes 10 mm or more as described above. That is, the winding roller 9 is introduced into the polymerization apparatus in a state where the polymerizable sheet 20 with the release film 11 attached is wound, and the atmosphere in the polymerization apparatus is heated to a predetermined polymerization temperature. Thus, polymerization of the polymerizable paste 5 is performed, and a raw film for introducing ion exchange groups can be obtained.

  In the present invention, it is important to carry out such polymerization in two stages or three or more stages. First, the polymerization is performed at a polymerization temperature 3 to 15 ° C. lower than the 10-hour half-life temperature of the polymerization initiator used. After performing the polymerization in the second stage, the polymerization in the second and subsequent stages is subsequently performed at a polymerization temperature that is 10 to 50 ° C. higher than the polymerization temperature in the first stage. Such multi-stage polymerization prevents the polymerization from proceeding at once, and the polymerization proceeds gradually in stages, thereby suppressing the generation of polymerization heat and effectively avoiding the quality deterioration of the resulting original film. be able to.

  That is, in the present invention, in order to increase the production efficiency, the number of windings of the polymerizable sheet 20 by the winding roller 9 is increased so that the total thickness becomes 10 mm or more. The polymerization heat generated in the inner part of the polymer sheet 20 is confined to the inner part facing the take-up roller 9, and as a result, the inner part of the polymerizable sheet 20 becomes remarkably higher than the outer surface side, and is formed by polymerization. In the film, wrinkles are generated particularly in the inner part or the base sheet 1 is deteriorated, and polymerization unevenness occurs between the inner side and the outer side, resulting in variations in various physical properties. In the present invention, the occurrence of heat of polymerization is suppressed by carrying out the polymerization in multiple stages, so that the deterioration of the quality of the original film as described above can be avoided.

  In the present invention, the polymerization temperature in the first stage is in the range of 3 to 15 ° C. lower than the 10-hour half-life temperature of the polymerization initiator, but if this polymerization temperature is higher than this range, Since the polymerization proceeds at once and the heat of polymerization is generated all at once, it is impossible to avoid deterioration of the quality of the original film. In addition, when the polymerization temperature in the first stage is lower than the above range, the polymerization does not proceed effectively, the polymerization time becomes long, and the number of windings of the polymerization sheet 20 is increased. In order to reduce the efficiency and increase the production efficiency, it is necessary to carry out the second-stage polymerization in a considerably high temperature region, and eventually the quality of the original film is lowered.

  Such polymerization in the first stage is carried out until an appropriate molecular weight is achieved, and, for example, although it varies depending on the composition of the polymerizable paste 5 to be used, etc., generally the methanol insoluble matter contained in the paste is based on the total paste amount. Specifically, the first stage polymerization is performed for about 4 to 12 hours until it reaches about 10 to 50%.

  The polymerization temperature in the second and subsequent stages is in a region 10 to 50 ° C. higher than the polymerization temperature in the first stage. When the polymerization temperature is higher than this range, the polymerization heat is lowered in the first stage polymerization. Even if it suppresses, the heat of polymerization in the polymerization in the second and subsequent stages will increase, and consequently it will not be possible to avoid degradation of the quality of the original film. On the other hand, if the polymerization temperature after the second stage is lower than the above range, the polymerization does not proceed effectively, unreacted monomers are generated, and the quality of the original film is deteriorated.

  Such polymerization in the second and subsequent stages is carried out until a desired resin having a high molecular weight original film is obtained. The methanol insoluble matter contained in the paste is about 70 to 95% of the total paste amount. Specifically, the time is about 0.5 to 5 hours. The polymerization after the second stage may be carried out in one stage, or may be carried out in multiple stages by dividing into two stages or three or more stages while gradually increasing the temperature within the above range.

  In the present invention, by performing the polymerization in multiple stages as described above, for example, the total thickness of the polymerizable sheet wound on the winding roller can be increased to 10 mm or more at the maximum.

<Raw membrane>
The original membrane obtained as described above is used as a cation exchange membrane or an anion exchange membrane after ion exchange groups are introduced after the heat of polymerization peels off the release film 11.

  The ion exchange group is introduced by means known per se, for example, sulfonation, chlorosulfonation, chloromethylation, amination, quaternary ammonium chlorination, phosphoniumation, sulfoniumation, hydrolysis and the like. Is done. The amount of ion exchange groups introduced is not particularly limited, but the ion exchange capacity is usually in the range of 0.1 to 20 meq / g · dry membrane, particularly 0.5 to 3 meq / g · dry membrane. Is good.

  The superior effect of the present invention is illustrated in the following example.

Examples 1-2
80 parts by weight of chloromethylstyrene, 10 parts by weight of styrene, 5 parts by weight of divinylbenzene for industrial use, 5 parts by weight of styrene-butadiene rubber, 5 parts by weight of dioctyl phthalate, and radical polymerization initiator benzoyl peroxide (10 hours half-life temperature 74 ° C.) 6 parts by weight was added to obtain a paste mixture.

  Next, the paste mixture is applied to a vinyl chloride base sheet (thickness: 100 μm), the polyester film is used as a release film on a take-up roller (outer diameter: 0.2 m), and the total thickness of the polymerizable sheet is 30 mm. It wound up so that it might become. Thereafter, the take-up roller was placed in an autoclave and placed in nitrogen gas at a pressure of 0.4 Mpa. As shown in Table 1, the polymerization temperature and time for the first stage and the polymerization time and time for the second stage were maintained. The obtained original film was immersed in trimethylamine at room temperature for 24 hours to perform a quaternization reaction. The membrane performance of the obtained ion exchange membrane is shown in Table 1.

Examples 3-4
10 parts by weight of chloromethylstyrene, 80 parts by weight of styrene, 5 parts by weight of industrial divinylbenzene, 15 parts by weight of tributyl citrate, 40 parts by weight of vinyl chloride powder and radical polymerization initiator lauryl peroxide (10 hours half-life temperature 62 ° C.) 3 parts by weight was added to obtain a paste mixture.

  Next, the paste mixture was applied to a vinyl chloride substrate sheet (thickness: 100 μm), and the polyester film was wound on a winding roller as a release film so that the total thickness of the polymerizable sheet was 20 mm. Thereafter, the take-up roller was placed in an autoclave and placed in nitrogen gas at a pressure of 0.4 Mpa. As shown in Table 2, the first stage polymerization temperature and time and the second stage polymerization time and time were maintained. The obtained original membrane was immersed in a 1: 1 mixed solution of 98% concentrated sulfuric acid and 90% chlorosulfonic acid at 40 ° C. for 60 minutes. The membrane performance of the obtained ion exchange membrane is shown in Table 2.

Comparative Examples 1-2
As shown in Table 3, the same procedure as in Example 1 was carried out except that the first stage polymerization temperature and time and the second stage polymerization time and time were maintained. Table 3 shows the membrane performance of the obtained ion exchange membrane.

The figure which shows the preparation and winding-up process of the polymeric sheet implemented by this invention. The figure which shows the layer structure of the polymeric sheet obtained at the process of FIG. 1 with a release film.

Explanation of symbols

1: base sheet 5: polymerizable paste 9: take-up roller 11: release film 20: polymerizable sheet

Claims (4)

A polymerizable sheet in which a base sheet is embedded inside a layer composed of a polymerizable paste containing a polymerizable monomer and a polymerization initiator is applied by a winding roller while a release film is attached to one surface thereof. In a method for producing an ion exchange membrane raw film by continuously winding and polymerizing the polymerizable paste in a state where a polymerizable sheet with a release film attached thereto is wound around a winding roller,
The polymerization of the polymerizable paste is performed with the total thickness of the polymerizable sheet on the winding roller being 10 mm or more, and the polymerization is performed by gradually increasing the polymerization temperature in multiple stages. Is carried out at a polymerization temperature that is 3 to 15 ° C. lower than the 10-hour half-life temperature of the polymerization initiator, and the second and subsequent polymerizations are carried out at a polymerization temperature that is 10 to 50 ° C. higher than the polymerization temperature of the first stage. A method for producing an ion-exchange membrane original membrane characterized by comprising: The production method according to claim 1 , wherein the polymerization in the first stage is carried out for 4 to 12 hours, and the polymerization in the second stage and thereafter is carried out for 0.5 to 5 hours. The manufacturing method according to claim 1 or 2 , wherein an outer diameter of the winding roller is 0.1 m or more.   The manufacturing method according to any one of claims 1 to 3, wherein a thickness of the base sheet is in a range of 10 to 500 µm, and a thickness of the polymerizable sheet is in a range of 10 to 1000 µm.

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