JP6416486B2 - Centrifugal thin film evaporator and method for producing polymer containing alicyclic structure for optical material - Google Patents

Description

  The present invention relates to a centrifugal thin film evaporator and a method for producing an alicyclic structure-containing polymer for optical materials.

  The production process of the alicyclic structure-containing polymer and the like includes a process of recovering the polymer by removing volatile components such as an inert solvent from the polymer solution containing the polymer. The centrifugal thin film evaporator that forms a thin film solution on the inner wall of the casing by the rotation of the stirring blade can efficiently remove volatile components contained in the solution in the production process of the polymer containing the alicyclic structure. It is attracting attention as a device.

  On the other hand, regarding the drying or recovery process of the alicyclic structure-containing polymer, by reducing the internal pressure of the centrifugal thin film evaporator and performing it in a low oxygen concentration atmosphere, coloring of the resulting alicyclic structure-containing polymer can be prevented. (See Patent Document 1 etc.).

JP 2001-316455 A

  Applications of the alicyclic structure-containing polymer are various, but when used as an optical material such as an optical film, it is necessary to realize high optical homogeneity. Against the background of such high quality requirements, the production of alicyclic structure-containing polymers for optical materials using conventional centrifugal thin film evaporators cannot sufficiently suppress the occurrence of minute optical defects called fish eyes. The problem that has arisen. That is, quality degradation due to optical defects of a minute size that has not been a problem in the past has been a problem, and it is required to suppress the occurrence of such optical defects.

  The inventors of the present invention have intensively studied the generation mechanism of minute optical defects, and as a result, confirmed that the resin oxide exists in the core of the optical defects and reduced the oxygen concentration of the centrifugal thin film evaporator. The present inventors have found that the generation of fish eyes in an alicyclic structure-containing polymer for optical materials can be suppressed.

  The present invention has been made in view of such a situation, and an object of the present invention is to use a centrifugal thin film evaporator that can realize evaporation and concentration in an oxygen concentration atmosphere lower than the conventional one, and such a centrifugal thin film evaporator. An object of the present invention is to provide a method for producing an alicyclic structure-containing polymer for optical materials capable of suppressing the occurrence of optical defects.

In order to achieve the above object, a centrifugal thin film evaporator according to the present invention comprises:
A casing portion to which a plurality of cylindrical members are joined, and a radial stirring blade having a rotation axis at the center of the casing portion, and a thin film solution on the inner wall of the casing portion by the rotation of the stirring blade In a centrifugal thin film evaporator that evaporates the solvent from the solution,
The cylindrical member has a flange portion at at least one end, and the plurality of cylindrical members are joined to each other via a flange joint structure portion in which two flange portions facing each other are combined.
Between the opposing surfaces of the two flange portions facing each other of the flange joint structure portion, a first seal member and a second seal member provided at a predetermined interval on the outer peripheral side from the first seal member are included. A plurality of ring-shaped sealing members are provided,
A first supply path for supplying an inert gas between the first seal member and the second seal member on the facing surface; and a first supply path for supplying an inert gas to an outer peripheral side of the second seal member on the facing surface. And 2 supply paths.

  A plurality of ring-shaped seal members including a first seal member and a second seal member are provided in the flange joint structure portion of the centrifugal thin film evaporator, and further between the first seal member and the second seal member, the second seal member By providing an inert gas supply path at two locations on the surface facing the outer periphery of the tube, it is possible to effectively prevent the problem that the outside air flows into the housing due to leakage from the seal portion and the internal oxygen concentration increases. it can.

  For example, the first seal member and the second seal member may be spiral gaskets.

  By using a spiral gasket rich in elasticity, good sealing performance is exhibited even when the diameters of the first seal member and the second seal member are large. In addition, since the inert gas is supplied to the flange joint structure portion, deterioration due to temperature of the filler material included in the spiral gasket can be prevented, and the spiral gasket as the first seal member and the second seal member can be prevented. Can maintain good sealing performance.

  Also, for example, one of the opposing surfaces of the two flange portions facing each other is between a convex surface portion that contacts the other opposing surface and the other opposing surface that is formed inside the convex surface portion. A concave surface portion sandwiching the first seal member and the second seal member may be formed.

  By providing the convex portion on the outside of the first seal member and the second seal member, the gap formed on the outside of the second seal member is reduced, so that intrusion of outside air into the housing is prevented, Alternatively, it is possible to suppress the supply amount of the inert gas through the second supply path.

  In addition, for example, one of the opposing surfaces of the two flange portions facing each other is disposed at a predetermined interval outside the first groove portion that houses the first seal member and the first groove portion. A second groove portion that accommodates the second seal member may be formed.

  By being accommodated in the first groove portion and the second groove portion, the first seal member and the second seal member exhibit suitable sealing performance. Further, since the gap formed between the two flange portions facing each other is reduced, it is possible to suppress the amount of inert gas supplied through the first supply path and the second supply path.

  Further, for example, the first supply path passes through one or the other of the two flange portions facing each other of the flange joint structure portion, and the first seal member and the second seal member An in-flange path that opens between them may be provided.

  Since the first supply path has an in-flange path, an inert gas can be supplied from the outside of the housing between the first seal member and the second seal member, and the first supply path has a simple shape. Can be configured.

  In addition, for example, the second supply path may include an outer peripheral path that surrounds opposed surfaces of the two flange portions facing each other of the flange joint structure portion from the outside.

  Since the 2nd supply path which has an outer periphery path | route can be comprised without performing a special process to a flange part, a structure is simple and can be provided easily.

Moreover, the method for producing an alicyclic structure-containing polymer for optical materials according to the present invention is a method for producing an alicyclic structure-containing polymer for optical materials using the centrifugal thin film evaporator described above,
A step of polymerizing an alicyclic structure-containing monomer in a solvent in the presence of a polymerization catalyst, and hydrogenating as necessary to obtain a solution containing the alicyclic structure-containing polymer;
Depressurizing the inside of the housing part;
Supplying an inert gas to the first supply path and the second supply path;
And evaporating the solvent from the solution by rotating the stirring blade while supplying the solution to the inside of the casing.

  According to the method for producing an alicyclic structure-containing polymer for an optical material according to the present invention, an optical material that prevents oxidation of the alicyclic structure-containing polymer in a centrifugal thin film evaporator and has few optical defects such as fish eyes. An alicyclic structure-containing polymer and an optical material can be obtained.

FIG. 1 is a schematic sectional view of a centrifugal thin film evaporator according to the present invention. 2 is an enlarged cross-sectional view of a main part of the II part shown in FIG. FIG. 3 is an enlarged cross-sectional view of a main part of the part III shown in FIG.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
The production method of the present invention comprises a step of polymerizing an alicyclic structure-containing monomer in a solvent in the presence of a polymerization catalyst, and hydrogenating as necessary to obtain a solution containing the alicyclic structure-containing polymer. A step of recovering the polymer from the solution containing the alicyclic structure-containing polymer using the centrifugal thin film evaporator 2 for evaporating the solvent from the obtained solution.

Centrifugal Thin Film Evaporator FIG. 1 is a schematic sectional view of a centrifugal thin film evaporator 2 used in the process of recovering a polymer. The centrifugal thin film evaporator 2 includes a cylindrical casing 4 and a radial stirring blade 8 having a rotation shaft 6 at the center of the casing 4, and the inner wall of the casing 4 is rotated by the rotation of the stirring blade 8. A thin film solution is formed on the substrate, and the solvent is evaporated from the solution.

  The housing | casing part 4 has five cylindrical members 4a, 4b, 4c, 4d, 4e arranged in the up-down direction. Each of the cylindrical members 4a to 4e has a flange portion at at least one end, and each of the cylindrical members 4a to 4e is a flange joint structure portion 20, 22, 24 in which two flange portions facing each other are combined. , 26 are joined to each other. The flange joint structure portions 20, 22, 24, 26 and their peripheral structures will be described in detail later.

  A heating jacket 10 is attached to the outer periphery of the cylindrical member 4c so that the inside of the housing 4 can be heated to a predetermined temperature. A raw material inlet 12 is formed on the upper side of the cylindrical member 4c, from which the raw material is introduced. A cylindrical member 4d and a cylindrical member 4e are disposed above the third cylindrical member 4c in which the raw material inlet 12 is formed. A motor 14 as a drive device is mounted on the upper part of the cylindrical member arranged at the uppermost position, and the motor 14 drives the rotary shaft 6 to rotate.

  A cylindrical member 4b and a cylindrical member 4a are disposed below the cylindrical member 4c. A bottom collection container 16 is connected to the lower part of the cylindrical member 4a arranged at the lowest position. In the centrifugal thin film evaporator 2, the recovered polymer is discharged from the discharge port 18 of the bottom recovery container 16.

  The cylindrical member 4a to which the bottom collection container 16 is connected is joined to the cylindrical member 4b disposed above the cylindrical member 4a via the flange joint structure portion 20. FIG. 2 is an enlarged cross-sectional view in which the peripheral portion of the flange joint structure portion 20 is enlarged.

  In the flange joint structure portion 20, the flange portion 30 provided at the upper end portion of the cylindrical member 4a and the flange portion 40 provided at the lower end portion of the cylindrical member 4b are combined so as to face each other. The flange portion 30 and the flange portion 40 are joined by being tightened in the vertical direction by bolts and nuts (not shown). The opposing surface 30a that is the upper surface of the flange portion 30 is opposed to the opposing surface 40a that is the lower surface of the flange portion 40, and there are a plurality of (two in the example shown in FIG. 2) between the two opposing surfaces 30a and 40a. ) Ring-shaped sealing member.

  The ring-shaped seal member disposed between the opposing surfaces 30a and 40a is constituted by a first spiral gasket 50 as a first seal member and a second spiral gasket 60 as a second seal member. And the gap between the flange portion 40 is sealed. The second spiral gasket 60 is concentrically provided outside the first spiral gasket 50 with a predetermined interval. The first spiral gasket 50 and the second spiral gasket 60 prevent outside air from flowing into the housing portion 4 from the flange joint structure portion 20.

  The first spiral gasket 50 and the second spiral gasket 60 have the same structure except that the outer diameter and the inner diameter are different, and have a ring shape continuous in the circumferential direction C as a whole. The first spiral gasket 50 includes an inner ring 52, a hoop material 54 joined to the outside of the inner ring 52, and a filler material 56 interposed between the hoop materials 54. The hoop material 54 has, for example, a bent shape such as a dogleg shape or a C shape, but the cross-sectional shape of the hoop material is particularly limited as long as it is elastically deformed in the compression direction (Z-axis direction in the figure). Not. The second spiral gasket 60 is also composed of an inner ring, a hoop material joined to the outer side of the inner ring, and a filler material 56 interposed between the hoop materials 54, except that the outer diameter and inner diameter thereof are different. The first spiral gasket 50 has the same structure.

  The opposing surface 30a, which is one of the two opposing surfaces 30a and 40a facing each other, has a convex surface portion 34 that contacts the other opposing surface 40a, and is formed on the inner side of the convex surface portion 34 and below the convex surface portion 34. A concave surface portion 32 is formed, and the first spiral gasket 50 and the second spiral gasket 60 are sandwiched between the concave surface portion 32 and the facing surface 40a. That is, as shown in FIG. 2, both ends of the hoop material 54 in the thickness direction (Z-axis direction in the drawing) are compressed in contact with the concave portion 32 of the opposing surface 30a and the opposing surface 40a, thereby exhibiting a sealing function. .

The flange joint structure portion 20 includes a first supply path 70 for supplying an inert gas between the first spiral gasket 50 and the second spiral gasket 60 on the opposing surfaces 30a and 40a, and a first supply path 70 on the opposing surfaces 30a and 40a. A second supply path 80 that supplies an inert gas to the outside of the two spiral gasket 60 is provided. The first supply path 70 passes through the inside of the flange portion 40 that is the other of the two flange portions 30 and 40 facing each other, and opens between the first spiral gasket 50 and the second spiral gasket 60. A first in-flange path 72 is provided. In addition, a first discharge path 74 is formed in the flange portion 40 at a position 180 degrees symmetrical to the first flange inner path 72, and is supplied from the first flange inner path 72 between the two spiral gaskets 50, 60. The inert gas thus discharged is discharged through the first discharge path 74.
In addition, it mentions later in the opposing surface 40a so that it may pass through the opening part of the path | route 72 in the 1st flange formed in the opposing surface 40a, and the opening part of the 1st discharge path 74 formed in the opposing surface 40a. Similar to the first circumferential groove 176, a circumferential groove having a predetermined depth continuous in the circumferential direction C may be formed.

  The second supply path 80 has an outer peripheral path 82 that surrounds the facing surfaces 30a, 40a of the two flange portions 30, 40 of the flange joint structure portion 20 facing each other from the outside. Between the outer circumferential path 82 and the second spiral gasket 60, the convex surface portion 34 and the facing surface 40a that contacts the convex surface portion 34 are disposed, but a sealing member is disposed between the convex surface portion 34 and the facing surface 40a. Therefore, at least a part of the inert gas in the second supply path 80 is supplied to the outside of the second spiral gasket 60. A second discharge path 84 for discharging the inert gas is connected to the outer peripheral path 82 at a position 180 degrees symmetrical to the connection position of the supply pipe for supplying the inert gas.

  The first supply path 70 and the second supply path 80 provided in the flange joint structure portion 20 prevent the outside air from flowing into the housing portion 4, and at the same time, the first and second spiral gaskets 50, 60. An inert gas is supplied to the periphery to prevent the first and second spiral gaskets 50 and 60 (particularly, the filler material 56) from being exposed to a high-temperature oxidizing environment.

  As shown in FIG. 1, the cylindrical member 4 b, the cylindrical member 4 c, and the cylindrical member 4 d are provided with flange portions at both ends, and the cylindrical member 4 b and the cylindrical member 4 c are connected via a flange joint structure portion 22. The cylindrical member 4c and the cylindrical member 4d are bonded via a flange bonding structure portion 24. Since the flange joint structure portion 22 and the flange joint structure portion 24 have the same structure as the flange joint structure portion 20 described above, description thereof is omitted.

  The cylindrical member 4e on which the motor 14 is mounted is joined to the cylindrical member 4d disposed below via a flange joint structure portion 26. FIG. 3 is an enlarged cross-sectional view in which a peripheral portion of the flange joint structure portion 26 is enlarged.

  In the flange joint structure portion 26, like the flange joint structure portion 20, the flange portion 130 of the cylindrical member 4 d and the flange portion 140 of the cylindrical member 4 e are combined so as to face each other. The facing surface 130a that is the upper surface of the flange portion 130 faces the facing surface 140a that is the lower surface of the flange portion 140, and two ring-shaped sealing members are provided between the two facing surfaces 130a and 140a. Yes.

  The ring-shaped seal member disposed between the opposed surfaces 130a and 140a is constituted by a first O-ring 150 as a first seal member and a second O-ring 160 as a second seal member, and the opposed surface 130a and the opposed surface 140a. The joint portion is sealed. The second O-ring 160 is provided concentrically outside the first O-ring 150 at a predetermined interval. The first O-ring 150 and the second O-ring 160 prevent outside air from flowing into the housing part 4 from the flange joint structure portion 26.

  The first O-ring 150 and the second O-ring 160 have a ring shape that is continuous in the circumferential direction C, and are usually formed of an elastic body such as rubber or elastomer, but the material of the O-ring is not particularly limited, and may be stainless steel or the like. The base metal may be used as a base material, and the surface thereof may be coated with a resin such as polytetrafluoroethylene.

  The first groove portion 132 that houses the first O-ring 150 and the first groove portion 132 are arranged on the opposite surface 130a, which is one of the two opposite surfaces 130a and 140a facing each other, with a predetermined interval between them. A second groove portion 134 that accommodates the ring 160 is formed.

  Similarly to the flange joint structure portion 20, the flange joint structure portion 26 also includes a first supply path 170 for supplying an inert gas between the first O-ring 150 and the second O-ring 160 on the opposite surfaces 130a and 140a, and the opposite surface. A second supply path 180 that supplies an inert gas to the outside of the second O-ring 160 in 130a and 140a is provided. The first supply path 170 has a first in-flange path 172 that passes through the inside of the flange portion 140 and opens to the facing surface 130 a between the first O-ring 150 and the second O-ring 160. An opening portion of the first in-flange path 172 to the facing surface 130 a intersects with a first circumferential groove 176 formed in the facing surface 140 a of the flange portion 140 and continuing in the circumferential direction C. Further, the flange portion 140 is formed with a first discharge path 174 that is connected to the first circumferential groove 176 at a 180-degree symmetrical position of the first flange inner path 172 and is inactive via the first discharge path 174. Gas is exhausted.

  The second supply path 180 has a second in-flange path 182 that passes through the inside of the flange portion 140 and opens to the opposing surface 130 a on the outer side of the second O-ring 160. An opening portion of the second in-flange path 182 to the facing surface 130a intersects with a second circumferential groove 186 formed in the facing surface 140a of the flange portion 140 and continuing in the circumferential direction C. Further, the flange portion 140 is formed with a second discharge path 184 that is connected to the second circumferential groove 186 at a 180-degree symmetrical position of the second flange inner path 182, and is inactive via the second discharge path 184. Gas is exhausted.

  Two groove portions including a first groove portion 132 and a second groove portion 134 are formed on the facing surface 130a of the flange portion 130, and the first circumferential groove 176 and the second circumferential surface are formed on the facing surface 140a of the flange portion 140. Two grooves formed of directional grooves 186 are formed. These four groove portions 132, 134, 176, and 186 are arranged so as to be displaced from each other in the radial direction R. That is, the first circumferential groove 176 is disposed between the first groove portion 132 and the second groove portion 134, and the second circumferential groove 186 is disposed outside the second groove portion 134.

  The first supply path 170 and the second supply path 180 provided in the flange joint structure portion 26 prevent the outside air from flowing into the inside of the housing unit 4 as in the flange joint structure portion 20 shown in FIG. In addition, an inert gas is supplied around the first O-ring 150 and the second O-ring 160 to prevent the first O-ring 150 and the second O-ring 160 from being exposed to a high-temperature oxidizing environment.

Method for producing alicyclic structure-containing polymer for optical material The solution containing the alicyclic structure-containing polymer supplied to the centrifugal thin film evaporator 2 described above is a solvent containing an alicyclic structure-containing monomer in the presence of a polymerization catalyst. Polymerized therein, and obtained by hydrogenation as necessary. The alicyclic structure-containing monomer has an alicyclic structure in the molecular structure. For example, a norbornene monomer, a monocyclic olefin monomer, a cyclic conjugated diene monomer, vinyl Examples thereof include alicyclic hydrocarbon monomers, and from the viewpoints of transparency and heat resistance of the resulting polymer, norbornene monomers are preferred.

  The norbornene monomer to which the present invention can be applied is a monomer known in JP-A-2-227424, JP-A-2-276842, etc., for example, norbornene; dicyclopentadiene, tricyclo [4. 3.0.12,5] -dec-3-ene, tricyclo [4.4.0.12,5] -undec-3,7-diene or tricyclo [4.4.0.12,5] -undeca -3,8-diene, tricyclo [4.4.0.12,5] -undec-3-ene, tetracyclo [7.4.0.110, 13.02,7] -trideca-2,4,6 , 11-tetraene (also referred to as 1,4-methano-1,4,4a, 9a-tetrahydrofluorene), tetracyclo [8.4.0.111,14.03,8] -tetradeca-3,5,7, 12-tetra Norbornene derivatives not attached to norbornane ring such as 1,4-methano-1,4,4a, 5,10,10a-hexahydroanthracene; tetracyclododecene, 8-methyl-tetracyclo [4.4 0.12, 5.17,10] -dodec-3-ene, 8-ethyl-tetracyclo [4.4.0.12,5. 17,10] -dodec-3-ene, 8-cyclopentyl-tetracyclo [4.4.0.12,5.17,10] -dodec-3-ene, 8-cyclohexyl-tetracyclo [4.4.0. 12, 5. And norbornene derivatives having a norbornane ring such as 17,10] -dodec-3-ene. In addition, these monomers include hydrocarbon groups such as alkyl groups, alkenyl groups, and alkylidene groups; groups containing nitrogen atoms, oxygen atoms, silicon atoms, phosphorus atoms, or sulfur atoms; other than double bonds of norbornene rings A double bond;

  Examples of the monocyclic olefin-based monomer include cyclohexene, cycloheptene, cyclooctene and the like.

  Examples of the cyclic conjugated diene monomer include cyclopentadiene and cyclohexadiene.

  Examples of the vinyl cyclic hydrocarbon monomer include vinylcyclohexene and vinylcyclohexane.

  These alicyclic structure-containing monomers can be used alone or in combination of two or more.

  The amount of the alicyclic structure-containing monomer is usually 50 to 100% by weight, preferably 70 to 100% by weight, more preferably 90 to 100% by weight, and particularly preferably 100% by weight based on the total monomers. . By setting the ratio of the alicyclic structure-containing monomer within this range, the mechanical strength of the resulting molded article is improved.

  In addition to the alicyclic structure-containing monomer, a monomer copolymerizable with the monomer (vinyl compound) can be used. Examples of the vinyl compound include ethylene, propylene, 1-butene, 1-pentyne, 1-hexene, 3-methyl-1-pentene, 8-methyl-1-pentene, 3-ethyl-1-pentene, 4- Methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4.4-dimethyl-1-benten, 4-ethyl-1-hexene, 3-ethyl-1-hexene, Chain vinyl compounds such as ethylene having 2 to 20 carbon atoms such as 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicocene, or α-olefin; -Non-conjugated diene compounds such as hexadiene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 1,7-octadiene; It is.

  These other monomers copolymerizable with these alicyclic structure-containing monomers can be used alone or in combination of two or more. The ratio of the other monomer copolymerizable with the alicyclic structure-containing monomer is usually 0 to 50% by weight, preferably 0 to 30% by weight, more preferably 0 to 10%, based on the total monomers. % By weight.

  Solvents that can be used for polymerization and hydrogenation reactions include alicyclic structure-containing monomers, alicyclic structure-containing polymers, and hydrogenated products of alicyclic structure-containing polymers that can be sufficiently dissolved, and polymerization reactions and hydrogenation. A solvent that does not inhibit the reaction (inert solvent) is preferably used. Specifically, alkanes such as pentane, hexane, heptane, octane, nonane, decane; cyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, dimethylcyclohexane, diethylcyclohexane, trimethylcyclohexane, cycloheptane, cyclooctane, decalin, norbornane Cycloalkanes such as methylnorbornane and ethylnorbornane; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene and cumene; chlorobutane, bromohexane, methylene chloride, dichloroethane, hexamethylene dibromide, chlorobenzene, chloroform, tetrachloroethylene, etc. Of halogenated alkanes, aryls, etc., among them, from the viewpoint of solubility, etc. Preferably class or aromatic hydrocarbons, cycloalkanes are more preferred.

  These solvents can be used alone or in combination of two or more.

  The amount of the solvent used is not particularly limited, but considering the balance between stirring efficiency and productivity, it is usually 40 to 2,000 parts by weight with respect to 100 parts by weight of the alicyclic structure-containing monomer, preferably Is from 100 to 1,000 parts by weight, more preferably from 250 to 600 parts by weight.

  The molecular weight of the alicyclic structure-containing polymer obtained in the polymerization step is appropriately selected depending on the purpose of use, but from the viewpoint of balance between mechanical strength and moldability, a cyclohexane solution (toluene if the polymer does not dissolve) The weight average molecular weight (Mw) in terms of polyisoprene (polystyrene in a toluene solution) measured by gel permeation chromatography method of solution, usually 5,000 or more, preferably 5,000 to 500,000, more preferably Is from 10,000 to 200,000, particularly preferably from 20,000 to 100,000. When the molecular weight is excessively large, not only the moldability is deteriorated, but also the hydrogenation reaction proceeds later when hydrogenation described later is performed, and the hydrogenation rate is lowered. On the other hand, if the molecular weight is excessively small, the mechanical strength of the polymer decreases.

  The molecular weight distribution (Mw / Mn) of the alicyclic structure-containing polymer obtained in the polymerization step is usually 7 or less, preferably 5 or less, more preferably 3.5 or less. When the molecular weight distribution is in the above range, the molded product molded using the polymer is not colored, and molding defects such as silver streaks and voids do not occur in the molded product.

  The alicyclic structure-containing polymer obtained in the polymerization step may be a homopolymer or a copolymer, and the copolymer may be a random copolymer or a block copolymer. Further, a (co) polymer obtained by graft-modifying these may be used.

  The norbornene-based monomer is polymerized by a known method disclosed in, for example, Japanese Patent Application Laid-Open No. 3-14882 and Japanese Patent Application Laid-Open No. 3-122137, to form a ring-opening polymer, an addition polymer, a copolymer. An addition copolymer with a polymerizable vinyl monomer can be used. Among these, in order to highly balance the heat resistance, transparency, and light resistance of the resulting alicyclic structure-containing polymer, a ring-opening polymer of a norbornene monomer is preferable.

  Ring-opening polymerization is a catalyst system comprising a norbornene-based monomer as a ring-opening polymerization catalyst, a metal halide such as ruthenium, rhodium, palladium, osmium, iridium, platinum, nitrate or acetylacetone compound, and a reducing agent, Alternatively, in the presence of a catalyst system comprising a metal halide such as titanium, vanadium, zirconium, tungsten, molybdenum, or an acetylacetone compound and an organoaluminum compound, a polymerization temperature of usually −50 to 100 ° C. in an inert solvent. The reaction can be carried out at a polymerization pressure of 0 to 5 MPa. In the catalyst system, molecular oxygen, alcohol, ether, peroxide, carboxylic acid, acid anhydride, acid chloride, ester, ketone, nitrogen-containing compound, sulfur-containing compound, halogen-containing compound, molecular iodine, other Lewis acids It is also possible to increase the polymerization activity and the selectivity of ring-opening polymerization by adding a third component such as.

  The addition polymerization of a norbornene monomer or the addition copolymerization of a norbornene monomer and a vinyl compound consists of, for example, a monomer component in a solvent, consisting of titanium, zirconium, or a vanadium compound and an organoaluminum compound. In the presence of a catalyst system, the polymerization can be usually carried out by a method of copolymerization at a polymerization temperature of -50 to 100 ° C and a polymerization pressure of 0 to 50 MPa.

  As for the polymerization of the monocyclic olefin monomer, addition polymerization can be carried out by a known method, for example, a method disclosed in JP-A No. 64-66216.

  The polymerization of the cyclic conjugated diene monomer is carried out by a known method, for example, a method disclosed in Japanese Patent Laid-Open Nos. 6-136057 and 7-258318, and 1,2- or 1,4-addition polymerization. The obtained polymer can be obtained.

  Polymerization of the vinyl alicyclic hydrocarbon monomer can be carried out, for example, by the method disclosed in JP-A-51-59989.

  In the present invention, when hydrogenation described later is not performed, it is preferable to include a step of removing the polymerization catalyst from the solution containing the polymer after the polymerization step. Even when the hydrogenation step is performed, a polymerization catalyst removal step may be included after the polymerization step. The catalyst residual amount in the reaction solution after removing the catalyst is usually 10 ppm or less, preferably 1 ppm or less, more preferably 0.1 ppm or less, based on the weight of the (catalyst) metal element with respect to the polymer in the reaction solution.

  In the present invention, the alicyclic structure-containing polymer obtained by the polymerization step has a carbon-carbon unsaturated bond (non-conjugated unsaturated bond and / or aromatic unsaturated bond, etc.) in the main chain and / or side chain. ), The hydrogenated product of the alicyclic structure-containing polymer can be obtained by saturating part or all of the unsaturated group. That is, in the present invention, a hydrogenation step may be included as necessary. Thus, when it has a carbon-carbon unsaturated bond, the heat resistance deterioration property and light deterioration resistance of an alicyclic structure containing polymer can be improved by hydrogenating the unsaturated group. In addition, when a carbon-carbon unsaturated bond is only an aromatic ring, whether to perform hydrogenation is selected according to the intended use of the alicyclic structure-containing polymer.

  When the polymer subjected to the hydrogenation reaction has an aromatic ring, the residual ratio of the aromatic ring is usually 80% or less, preferably 50% or less, more preferably 30% or less from the viewpoint of light resistance and the like. The hydrogenation rate of the non-conjugated unsaturated bond is usually 80% or more, preferably 90% or more, more preferably 95% or more. If the hydrogenation rate is low, it tends to cause oxidative deterioration and molecular cutting, resulting in poor color, reduced transparency, and reduced mechanical strength.

  In the case where the alicyclic structure-containing polymer has a repeating unit having an aromatic ring, the aromatic ring structure can be left in the hydrogenation reaction, but may be completely hydrogenated. In addition, by analysis by 1H-NMR, the unsaturated bond of the aromatic ring can be distinguished from other unsaturated bonds.

  The hydrogenation reaction is carried out according to a conventional method by bringing the polymer into contact with hydrogen in the presence of a hydrogenation catalyst. Examples of the hydrogenation catalyst are disclosed in JP-A-58-43412, JP-A-60-26024, JP-A-64-24826, JP-A-1-138257, JP-A-7-41550, and the like. What is described can be used and can be homogeneous or heterogeneous. Homogeneous catalysts are easy to disperse in the hydrogenation reaction solution, so the addition amount may be small, and since they are active without high temperature and pressure, the polymer does not decompose or gel, and low cost and quality Excellent stability. Heterogeneous catalysts are highly active at high temperatures and pressures, and are excellent in production efficiency, such as being able to be hydrogenated in a short time and being easily removed. Among these, a heterogeneous catalyst is preferable because it can be easily removed.

  Examples of homogeneous catalysts include so-called Wilkinson complexes such as chlorotris (triphenylphosphine) rhodium (I); cobalt acetate / triethylaluminum, nickel acetylacetonate / triisobutylaluminum, titanocene dichloride / n-butyllithium, zirconocene dichloride / a catalyst comprising a combination of a transition metal compound / alkyl metal compound such as sec-butyllithium, tetrabutoxytitanate and dimethylmagnesium;

  Examples of the heterogeneous catalyst include a catalyst in which a hydrogenation catalyst metal such as Ni, Pd, Pt, Ru, Rh or the like is supported on a carrier. In particular, it is preferable to use an adsorbent such as alumina or diatomaceous earth as a carrier with less contamination of impurities and the like. These catalysts are used in the range of 0.001 to 50 parts by weight, preferably 0.01 to 30 parts by weight with respect to 100 parts by weight of the polymer. The hydrogenation catalyst can be added to the polymerization reaction solution as it is, or can be added and reacted after removing the polymerization catalyst from the polymerization reaction solution.

  The hydrogenation reaction is usually carried out in a solvent. The solvent is not particularly limited as long as it is inert to the catalyst, and may be the same as the polymerization reaction solvent or may be further added to the polymerization reaction solution. The amount of the inert solvent used for hydrogenation is usually 1 to 100 times, preferably 1.5 to 20 times, more preferably on a weight basis with respect to the polymer in the polymerization reaction solution, from the viewpoint of hydrogenation reaction efficiency. Is 2 to 10 times.

  The hydrogenation reaction can be carried out according to a conventional method, but the hydrogenation rate varies depending on the type of hydrogenation catalyst and the reaction temperature, and the remaining ratio of the aromatic ring can also be varied. When the above hydrogenation catalyst is used, in order to leave the unsaturated bond of the aromatic ring to a certain extent or more, control such as lowering the reaction temperature, lowering the hydrogen pressure, or shortening the reaction time may be performed. . In order to selectively increase the hydrogenation rate of non-conjugated unsaturated bonds in the main chain while leaving the aromatic ring structure in the polymer completely without hydrogenation, the hydrogen pressure in the reactor is usually increased. 0.01 to 5 MPa, preferably 0.05 to 4 MPa, more preferably 0.1 to 3 MPa. When using a homogeneous catalyst, the reaction temperature of the hydrogenation reaction is usually −10 to 150 ° C., preferably 0 to 130 ° C., more preferably 20 to 110 ° C. When a heterogeneous catalyst is used, it is usually carried out at 0 to 300 ° C, preferably 100 to 250 ° C, more preferably 150 to 230 ° C.

  The molecular weight of the hydrogenated product of the alicyclic structure-containing polymer obtained in the hydrogenation step is appropriately selected according to the purpose of use, but gel permeation of cyclohexane solution (toluene solution if the polymer does not dissolve) The weight average molecular weight (Mw) in terms of polyisoprene (polystyrene in a toluene solution) measured by a chromatographic method is usually 5,000 or more, preferably 5,000 to 500,000, more preferably 8,000 to 200,000. Especially preferably, it is 10,000-100,000.

  The molecular weight distribution Mw / Mn of the hydrogenated product of the alicyclic structure-containing polymer obtained in the hydrogenation step is usually 7 or less, preferably 5 or less, more preferably 3.5 or less.

  The glass transition temperature (Tg) of the hydrogenated product of the alicyclic structure-containing polymer obtained in the hydrogenation step is usually 50 to 250 ° C, preferably 70 to 220 ° C, more preferably 80 to 200 ° C.

  In this invention, it is preferable after the said hydrogenation process to include the process of removing a hydrogenation catalyst from the solution containing the hydrogenated product of a polymer. In addition, it is good also as removing both a polymerization catalyst and a hydrogenation catalyst at once after hydrogenation, without performing the said polymerization catalyst removal process. The removal method and the catalyst residual amount after removal are performed in the same manner as in the polymerization catalyst removal step.

  In the present invention, the solution containing the hydrogenated product after removing the hydrogenation catalyst may be filtered with a mechanical filter or a filter having a charge capturing function. About the method of filtering with a filter, it can carry out by the method of Unexamined-Japanese-Patent No. 10-60048.

  In the present invention, it is preferable to have a preconcentration step for increasing the polymer concentration before the polymer is recovered by the centrifugal thin film evaporator described above. In this step, the concentration of the polymer contained in the solution is preferably 30 to 99% by weight, more preferably 50 to 99% by weight, and particularly preferably 90 to 99% by weight. Even when the polymer concentration in the solution immediately after the reaction has already exceeded 30% by weight as described above, it is possible to reduce the deterioration of the polymer by increasing the polymer concentration within the above range. preferable.

  The preconcentration is performed by heating or depressurizing the polymer solution in a state where the polymer solution is stored in the container. In that case, it is preferable not to apply shear stress to the polymer in the solution.

  If the polymer concentration of the solution is too low, the amount of volatile components increases in the recovery step described later, and the degree of reduced pressure does not increase, so the amount of volatile components in the polymer after drying increases. If the amount of the volatile component after recovery is too large, molding defects such as silver streaks, voids and foaming occur in the molded product, which is not preferable. In addition, a large amount of heat of vaporization increases the temperature of the polymer solution, causing a sudden increase in viscosity and solidification in the evaporator, which interrupts the recovery process and damages the equipment.

  In the method of the present invention, the apparatus suitable for the preconcentration step includes (1) an apparatus capable of concentrating the reaction solution by bringing the evaporator under reduced pressure, and (2) a pressurized reaction solution at normal pressure. Examples include a device that can be supplied into the evaporator and instantaneously remove (flash) the solvent, and (3) a device that can be concentrated by stirring and heating under atmospheric pressure in a vessel equipped with a stirring device and a heating device. As a more specific apparatus name, an apparatus such as an evaporator represented by a flash box, a flash separator, and a hibiscus (manufactured by Mitsui Engineering & Shipbuilding) can be used.

  In the present invention, it is preferable to have a preheating step of heating the polymer solution before the preconcentration step. By preheating the reaction solution before preconcentration, the concentration efficiency of the polymer is improved. As a preheating method, (1) a method of heating a polymer solution storage container before concentration and / or a transfer pipe from the storage container to the solvent removal apparatus with a jacket type heating apparatus, (2) many A method using a known heat exchanger such as a tube heat exchanger or a plate fin type heat exchanger can be mentioned. When using a heat exchanger, it is not always necessary to install it outside the solvent removal apparatus, and an integrated solvent removal apparatus with a built-in heat exchanger may be used if necessary.

  The temperature of the solution at the time of preheating is usually 50 to 400 ° C, preferably 70 to 350 ° C, more preferably 100 to 330 ° C. If the heating temperature is too low, the evaporation efficiency is deteriorated, and in order to increase the concentration, it is necessary to increase the residence time in the solvent removing apparatus, which causes problems such as a decrease in productivity and thermal deterioration of the polymer. On the other hand, when the preheating temperature is too high, the polymer is undesirably deteriorated by heat.

  In the present invention, the preliminary concentration step is preferably performed in a low oxygen concentration atmosphere. By performing the pre-concentration step in a low oxygen concentration atmosphere, coloring of the alicyclic structure-containing polymer finally recovered can be effectively prevented. The low oxygen concentration atmosphere is preferably adjusted so that the oxygen concentration is 0.1 volume% or less, more preferably 0.01 volume% or less. By setting the working atmosphere to a lower oxygen concentration, oxidation of the polymer is prevented and coloring of the resulting molded product is prevented. As a specific means for creating such a low oxygen concentration atmosphere, there is a method of making the inside of the apparatus used for the preconcentration step an inert gas atmosphere such as nitrogen or helium.

  In the present invention, the polymer is recovered from the solution containing the alicyclic structure-containing polymer obtained by the above method using a centrifugal thin film evaporator. The process of recovering the alicyclic structure-containing polymer will be described using the centrifugal thin film evaporator 2 shown in FIGS.

  In the step of recovering the alicyclic structure-containing polymer, first, the internal pressure of the housing part 4 is reduced to the first pressure. The first pressure is preferably 20 kPa or less, more preferably 10 kPa or less, and particularly preferably 3 kPa or less. When the internal pressure is larger than the above range, the evaporation efficiency of the polymer solution is deteriorated, and the amount of volatile components in the polymer after recovery is increased. As a method for lowering the internal pressure of the housing part 4, there is a method of sucking the inside of the evaporator from the exhaust port 17 by a vacuum pump, but it is not particularly limited. The casing 4 is heated to a predetermined temperature by the heating jacket 10. The heating temperature is preferably 240 to 350 ° C, more preferably 250 to 330 ° C.

  Further, in the step of recovering the alicyclic structure-containing polymer, an inert gas is supplied to the first supply passages 70 and 170 and the second supply passages 80 and 180, so that each of the opposing surfaces 30a, 130a, 40a and 140a An inert gas atmosphere is provided between the first seal member (first spiral gasket 50, first O-ring 150) and the second seal member (second spiral gasket 60, second O-ring 160) and outside the second seal member. To do. The inert gas passes through the periphery of the first seal member or the second seal member and is discharged from the first discharge paths 74 and 174 and the second discharge paths 84 and 184. The inert gas is continuously supplied to the first supply path 70 and the second supply path 80 from, for example, an inert gas tank (not shown). Examples of the inert gas supplied to the first supply paths 70 and 170 and the second supply paths 80 and 180 include nitrogen, argon, and helium, but are not particularly limited. Further, the pressure and flow rate of the inert gas are not particularly limited, but the pressure of the inert gas supplied to the first supply passages 70 and 170 and the second supply passages 80 and 180 is the internal pressure of the housing unit 4. It is preferably higher than a certain first pressure.

  After preparing the centrifugal thin film evaporator 2, a solution containing the alicyclic structure-containing polymer (polymer solution) is supplied to the raw material inlet 12. The polymer solution supplied to the raw material inlet 12 is introduced into the casing 4 from the raw material inlet 12. At this time, the rotating shaft 6 and the stirring blade 8 provided inside the housing unit 4 are rotated by the driving force transmitted through the output shaft of the motor 14. The polymer solution introduced into the housing part 4 forms a liquid film on the upper surface of the inner wall of the housing part 4 due to the centrifugal force generated by the rotation of the stirring blade 8. Volatile components in the polymer solution that has become a liquid film are heated by the heating jacket 10 to evaporate. The evaporated volatile component is discharged out of the housing part 4 through an exhaust port 17 provided on the side of the bottom recovery container 16, and the polymer is recovered from a discharge port 18 provided below the bottom recovery container 16. The

  In the present invention, two or more centrifugal thin film evaporators described above may be used. In this case, different internal pressures and / or heating temperatures may be used for each centrifugal thin film evaporator.

  According to the present invention, the amount of volatile components in the alicyclic structure-containing polymer can be preferably 100 ppm or less, more preferably 50 ppm or less. The molecular weight measured by gel permeation chromatography (GPC) in the alicyclic structure-containing polymer is 1000 or less in terms of polystyrene, preferably 1% by weight or less, more preferably 0.5% by weight or less. An alicyclic structure-containing polymer can be obtained.

  The alicyclic structure-containing polymer obtained by the present invention is particularly suitable for an optical material such as an optical film, a plastic lens, and an optical disk because it has few minute optical defects called fish eye. In order to obtain such a molded article, a compounding agent that is usually blended in a thermoplastic resin material can be added without particular limitation, if necessary. Such compounding agents include, for example, antioxidants, ultraviolet absorbers, light stabilizers, near infrared absorbers, colorants such as dyes and pigments, lubricants, plasticizers, antistatic agents, fluorescent whitening agents, Examples include compounding agents such as a flame retardant and an anti-blocking agent.

  The method of blending the above compounding agent into the alicyclic structure-containing polymer obtained by the present invention is, for example, a molten state of the alicyclic structure-containing polymer hydrogenated product in a mixer, a twin-screw kneader, a roll, a Brabender, an extruder, or the like. And a method of kneading with a compounding agent, a method of dissolving and dispersing in an appropriate solvent and solidifying. When a twin-screw kneader is used, it is often used after being kneaded and usually extruded in the form of a strand in a molten state and cut into a pellet by a pelletizer.

  Although there is no special limitation as a molding method, it is preferable to use a melt molding method in order to obtain a molded product excellent in low birefringence, mechanical strength, dimensional accuracy, and the like. Examples of the melt molding method include an injection molding method, an extrusion molding method, a press molding method, and a blow molding method. From the viewpoint of low birefringence and dimensional stability, the injection molding method is preferable. Moreover, as an optical film molding method, an extrusion molding method is preferably used in terms of excellent productivity.

  The centrifugal thin film evaporator 2 described above prevents the outside air (especially oxygen) from flowing into the housing part 4 in the recovery process of the alicyclic structure-containing polymer, and the alicyclic structure in the housing part 4. The oxidation of the containing polymer can be effectively prevented. Therefore, by using such a centrifugal thin film evaporator 2, an alicyclic structure-containing polymer for an optical material and an optical material having few optical defects such as fish eyes are produced by producing an alicyclic structure-containing polymer for an optical material. Can be obtained. Further, even when a spiral gasket having a hoop material 54 such as PTFE (polytetrafluoroethylene) is employed as the seal member, the spiral gaskets 50 and 60 are placed in a low oxygen concentration environment. Thus, it is possible to effectively prevent the PTFE of the hoop material 54 from being thermally decomposed, and to improve the sealing performance of the flange joint structure portions 20, 22, and 24.

  The centrifugal thin film evaporator 2 shown as the embodiment can be variously modified according to the properties and applications of the alicyclic structure-containing polymer, the size of the centrifugal evaporator, and the like. For example, the first and second seal members are not limited to spiral gaskets and O-rings, and other seal members such as metal gaskets, soft gaskets, and metal jacket gaskets can be applied. Further, the first seal member and the second seal member may be constituted by seal members made of the same material, or may be constituted by seal members made of different materials.

  Further, the first flange inner paths 72 and 172 and the second flange inner path 182 shown in FIGS. 2 and 3 may be provided in the flange portions 40 and 140 where the concave surface portion 32 and the groove portions 132 and 134 are not formed. Although it is good, you may provide in the flange parts 30 and 130 in which the concave surface part 32 and the groove parts 132 and 134 are formed.

  The application of the centrifugal thin film evaporator 2 is not limited to the step of recovering the alicyclic structure-containing polymer, and can be used for various steps of drying and evaporation under a low pressure or an inert gas atmosphere.

2 ... Centrifugal thin film evaporator 4 ... Housing parts 4a-4e ... Cylindrical member 8 ... Stirring blades 20-26 ... Flange joint structure parts 30, 40, 130, 140 ... Flange parts 30a, 40a, 130a, 140a ... Opposing surfaces 32 ... Concave portion 34 ... Convex portion 50, 60 ... Spiral gasket 70, 80, 170, 180 ... Supply path 72, 172, 182 ... Flange inner path 82 ... Outer peripheral path 84 ... Second discharge path 132, 134 ... Groove 150 , 160 ... 1st O-ring

Claims (7)

A casing portion to which a plurality of cylindrical members are joined, and a radial stirring blade having a rotation axis at the center of the casing portion, and a thin film solution on the inner wall of the casing portion by the rotation of the stirring blade In a centrifugal thin film evaporator that evaporates the solvent from the solution,
The cylindrical member has a flange portion at at least one end, and the plurality of cylindrical members are joined to each other via a flange joint structure portion in which two flange portions facing each other are combined.
A plurality of first seal members and a plurality of second seal members provided at predetermined intervals outside the first seal members are provided between the opposing surfaces of the two flange portions facing each other of the flange joint structure portion. Ring-shaped seal member is provided,
A first supply path for supplying an inert gas between the first seal member and the second seal member on the opposing surface; and a second supply passage for supplying an inert gas to the outside of the second seal member on the opposing surface. A centrifugal thin film evaporator, characterized in that a supply path is provided.   The centrifugal thin film evaporator according to claim 1, wherein the first seal member and the second seal member are spiral gaskets.   One of the opposing surfaces of the two flange portions facing each other is formed between the convex surface portion that contacts the other opposing surface and the other opposing surface that is formed inside the convex surface portion. The centrifugal thin film evaporator according to claim 1 or 2, wherein a sealing member and a concave portion sandwiching the second sealing member are formed.   One of the opposing surfaces of the two flange portions facing each other is arranged with a first groove portion for accommodating the first seal member and a predetermined space outside the first groove portion with a predetermined interval therebetween. The centrifugal thin-film evaporator according to claim 1 or 2, wherein a second groove portion for accommodating the second groove portion is formed.   The first supply path passes through one or the other of the two flange portions facing each other of the flange joint structure portion, and opens between the first seal member and the second seal member. The centrifugal thin film evaporator according to claim 3 or 4, which has a path in the flange.   The said 2nd supply path | route has an outer periphery path | route which surrounds the opposing surface of two said flange parts which the said flange joining structure part mutually opposes from the outer side, The Claim 1 to Claim 5 characterized by the above-mentioned. Centrifugal thin film evaporator. A method for producing an alicyclic structure-containing polymer for an optical material using the centrifugal thin film evaporator according to any one of claims 1 to 6,
A step of polymerizing an alicyclic structure-containing monomer in a solvent in the presence of a polymerization catalyst, and hydrogenating as necessary to obtain a solution containing the alicyclic structure-containing polymer;
Depressurizing the inside of the housing part;
Supplying an inert gas to the first supply path and the second supply path;
A process of evaporating the solvent from the solution by rotating the stirring blade while supplying the solution to the inside of the casing;
The manufacturing method of the alicyclic structure containing polymer for optical materials containing this.

Images