JP2009178941A - Method of manufacturing molded article and optical injection molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a molded article excellent in heat resistance by using a polymer excellent in moldability, and an optical injection molded article excellent in heat resistance and moldability. <P>SOLUTION: In the method of manufacturing the molded article, a cycloolefinic polymer is injection-molded which contains 20-50 wt.% of a repeating unit originating from dicyclopentadiene per 100 wt.% of the whole repeating unit, and 50-80 wt.% of a repeating unit originating from a specific norbornene type compound per 100 wt.% of the whole repeating unit, and of which the polystyrene converted weight average molecular weight due to gel permeation chromatography is 35,000-55,000. The optical injection molded article is also disclosed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a molded body using a specific cyclic olefin polymer and an optical injection molded body.

The cyclic olefin ring-opening (co) polymer has a high glass transition temperature due to the rigidity of the main chain structure, and is amorphous and has a high light transmittance due to the presence of bulky groups in the main chain structure. In addition, it has features such as low birefringence due to its low refraction anisotropy, and has attracted attention as a transparent thermoplastic resin excellent in heat resistance, transparency and optical properties. Examples of such cyclic olefin-based ring-opening (co) polymers include those described in Patent Documents 1 to 6.
Utilizing the above characteristics, it is considered to apply cyclic olefin-based ring-opening (co) polymers in fields such as optical materials such as optical disks, optical lenses, optical fibers, and sealing materials such as optical semiconductor sealing. Has been. In other words, films such as polycarbonate, polyester, and triacetyl acetate that have been used as optical films in the past have a large photoelastic coefficient. In order to solve these problems, a molded body made of a cyclic olefin-based ring-opening (co) polymer has been proposed.

However, cyclic olefin-based ring-opening (co) polymers with excellent heat resistance are difficult to mold due to insufficient fluidity, and improving the fluidity lowers the glass transition temperature of the polymer, resulting in insufficient heat resistance. There was a problem of doing. For this reason, a polymer having excellent heat resistance, sufficient fluidity and excellent moldability has been strongly desired.
Japanese Patent Laid-Open No. 1-132625 JP-A-1-132626 JP 63-218726 A JP-A-2-133413 JP 61-120816 A Japanese Patent Laid-Open No. 61-115912

  An object of the present invention is to provide a method for producing a molded article having excellent heat resistance using a polymer having excellent moldability, and an optical injection molded article having excellent heat resistance and moldability.

  The method for producing a molded article of the present invention comprises a repeating unit represented by the following formula (1) (hereinafter also referred to as “repeating unit (1)”) in an amount of 20 to 50% by weight based on 100% by weight of all the repeating units, Polystyrene by gel permeation chromatography having a repeating unit represented by the following formula (2) (hereinafter also referred to as “repeating unit (2)”) in an amount of 50 to 80 wt% with respect to 100 wt% of all repeating units. A cyclic olefin polymer having a converted weight average molecular weight of 35,000 to 55,000 is molded by injection molding.

(In Formula (2), R < ¹ > -R < ⁴ > is respectively independently a hydrogen atom, a halogen atom, a C1-C10 hydrocarbon group, or a polar group, provided that at least one of R < ¹ > -R < ⁴ >. Is a polar group, and any two of R ^{1 to} R ⁴ may be bonded to each other to form a monocyclic or polycyclic structure, and m is 0 or 1.)

  The weight average molecular weight in terms of polystyrene by gel permeation chromatography of the cyclic olefin polymer in the production method of the present invention is preferably 35,000 to 55,000.

  In the optical injection molded product of the present invention, the repeating unit (1) is 20 to 50% by weight with respect to 100% by weight of all repeating units, and the repeating unit (2) is 50 to 80% by weight with respect to 100% by weight of all repeating units. And a cyclic olefin polymer having a polystyrene-reduced weight average molecular weight of 35,000 to 55,000 as determined by gel permeation chromatography.

  According to the present invention, by using a cyclic olefin-based ring-opening copolymer having two specific types of repeating units at a specific ratio, a method for producing a molded article having excellent moldability and excellent heat resistance is provided. be able to. Moreover, according to this invention, the optical injection molded object excellent in the heat resistance and moldability using this resin composition can be provided.

Hereinafter, the present invention will be specifically described.
Cyclic Olefin Polymer The cyclic olefin polymer used in the present invention has a repeating unit (1) of 20 to 50% by weight based on 100% by weight of all repeating units and a repeating unit (2) of 100% by weight of all repeating units. It is a ring-opening copolymer hydride having 50 to 80% by weight based on the weight.
Monomers that give the repeating unit (1) (hereinafter also referred to as “monomer (1)”) include tricyclo [4.3.0.1 ^2,5 ] dec-3-ene and tricyclo [4. 3.0.1 ^2,5 ] Deca-3,7-diene (dicyclopentadiene). When tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene is used, the repeating unit (1) is obtained by hydrogenation of a five-membered ring after ring-opening copolymerization.

  The monomer giving the repeating unit (2) (hereinafter also referred to as “monomer (2)”) is represented by the following formula (2m).

In formula (2m), m and R ^{1 to} R ⁴ are the same as in formula (2). That is, R ^{1 to} R ⁴ are each independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a polar group, provided that at least one of R ^{1 to} R ⁴ is a polar group. . Further, any two of R ^{1 to} R ⁴ may be bonded to each other to form a monocyclic or polycyclic structure. m is 0 or 1.

  In the formula (2) or (2m), examples of the polar group include a hydroxyl group, an alkoxy group having 1 to 10 carbon atoms, a carbonyloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, a cyano group, an amide group, and an imide. Group, triorganosiloxy group, triorganosilyl group, amino group, acyl group, alkoxysilyl group, sulfonyl group, carboxyl group and the like. More specifically, examples of the alkoxy group include a methoxy group and an ethoxy group; examples of the carbonyloxy group include an alkylcarbonyloxy group such as an acetoxy group and a propionyloxy group, and an aryl such as a benzoyloxy group. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group; examples of the aryloxycarbonyl group include a phenoxycarbonyl group, a naphthyloxycarbonyl group, a fluorenyloxycarbonyl group, Biphenylyloxycarbonyl group and the like; examples of the triorganosiloxy group include trimethylsiloxy group and triethylsiloxy group; examples of the triorganosilyl group include trimethylsilyl group, Such Riechirushiriru group and the like; examples of the amino group include primary amino group, the alkoxysilyl group, for example trimethoxysilyl groups, such as triethoxysilyl group.

Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.
Examples of the hydrocarbon group having 1 to 10 carbon atoms include alkyl groups such as methyl group, ethyl group, and propyl group; cycloalkyl groups such as cyclopentyl group and cyclohexyl group; alkenyl groups such as vinyl group, allyl group, and propenyl group. Groups and the like.

Here, in the repeating unit (2) and the monomer (2), the polar group is preferably a group represented by the following formula (4). That is, in formula (2) or formula (2m), at least one of R ^{1 to} R ⁴ is preferably a group represented by the following formula (4).

_{- (CH 2) p COOR '} ··· (4)
(In Formula (4), p is 0 or an integer of 1 to 5, and R ′ is a hydrocarbon group having 1 to 15 carbon atoms.)
In the above formula (4), the smaller the value of p and the smaller the R ′ carbon number, the higher the glass transition temperature of the resulting copolymer and the better the heat resistance. That is, p is usually 0 or an integer of 1 to 5, preferably 0 or 1, and R 'is usually a hydrocarbon group having 1 to 15 carbon atoms, preferably 1 to 3 carbon atoms. It is desirable that it is an alkyl group.

  When the polar group has a repeating unit (2) which is a group represented by the above formula (4), the copolymer is excellent in heat resistance and water absorption (wet) property, which is preferable. The number of carbon atoms of the alkyl group further bonded to the carbon atom to which the polar group represented by the above formula (4) is bonded is preferably 1 to 5, more preferably 1 to 2, particularly preferably 1. is there.

As such a monomer (2), specifically, for example,
5-methyl-5-methoxycarbonyl-bicyclo [2.2.1] hept-2-ene,
5-methyl-5-phenoxycarbonyl-bicyclo [2.2.1] hept-2-ene,
5-methyl-6-methoxycarbonyl-bicyclo [2.2.1] hept-2-ene,
5-methyl-6-phenoxycarbonyl-bicyclo [2.2.1] hept-2-ene,
8-methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8-ethoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene,
8-methyl-8-n-propoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8-methyl-8-isopropoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8-methyl-8-n-butoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene,
8-methyl-8-phenoxycarbonyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene etc. can be mentioned, but it is not limited to these examples.

  The cyclic olefin polymer according to the present invention has the repeating unit (1) in an amount of 20 to 50% by weight, preferably 20 to 40% by weight, particularly preferably 20 to 30% by weight based on 100% by weight of all repeating units. The repeating unit (2) preferably has 50 to 80% by weight, preferably 60 to 80% by weight, particularly preferably 70 to 80% by weight, based on 100% by weight of all repeating units. When the proportion of the repeating unit (1) is less than 20% by weight, there is a problem that the fluidity is insufficient, and when it exceeds 50% by weight, there is a problem that the heat resistance is lowered.

  The cyclic olefin polymer according to the present invention may be a copolymer consisting only of the repeating unit (1) and the repeating unit (2), but if necessary, within a range not impairing the object of the present invention. It may have a repeating unit derived from another copolymerizable monomer. As the repeating unit derived from other copolymerizable monomer, a repeating unit derived by ring-opening copolymerization of a cyclic olefin monomer having a norbornene skeleton other than the repeating unit (1) or (2) is preferable. Examples thereof include repeating units derived by ring-opening copolymerization of cycloolefin monomers such as cyclobutene, cyclopentene, cycloheptene, and cyclooctene.

  Such a cyclic olefin polymer can be produced by ring-opening copolymerization and hydrogenation of the monomer (1), the monomer (2) and other monomers as required.

  The molecular weight of the cyclic olefin polymer used in the present invention is preferably a polystyrene-converted weight average molecular weight (hereinafter also referred to as “Mw”) measured by gel permeation chromatography (hereinafter also referred to as “GPC”). Is 35,000-55,000, more preferably 40,000-50,000. If Mw is less than 35,000, the strength of the resulting molded product may be low, and if it exceeds 55,000, fluidity may be insufficient and moldability may be insufficient. The number average molecular weight (hereinafter also referred to as “Mn”) in terms of polystyrene measured by GPC is preferably 10,000 to 25,000, and more preferably 10,000 to 20,000. The molecular weight distribution (Mw / Mn) of the cyclic olefin polymer used in the present invention is usually 2.0 to 3.5, preferably 2.5 to 3.5.

  The glass transition temperature (Tg) of the cyclic olefin polymer used in the present invention is preferably 110 ° C. or higher, more preferably 125 to 250 ° C., further preferably 125 to 220 ° C., and particularly preferably 130 to 220 ° C. 200 ° C. A Tg of 110 ° C. or higher is preferable because of excellent heat resistance. When Tg is less than 110 ° C., the heat distortion temperature becomes low, which may cause a problem in heat resistance, and the problem that the change in optical properties due to temperature in the obtained molded article increases. There is. On the other hand, when Tg exceeds 250 ° C., the molding temperature becomes too high, and the copolymer of the present invention may be thermally deteriorated.

  About the manufacturing method of a cyclic olefin type polymer, in the case of copolymerization of each monomer mentioned above, it can carry out by selecting the polymerization conditions suitably in consideration of the reactivity of each monomer to be used. During copolymerization, it is preferable that the monomer composition ratio in the polymerization system does not change significantly between the initial and late stages of polymerization, and when the monomer concentration changes over time, the polymerization is stopped at an early stage. Alternatively, it is preferable to keep the monomer composition ratio constant by supplying the monomer having a reduced concentration into the polymerization system continuously or intermittently into the polymerization system. When copolymerization is performed while controlling the monomer composition ratio in this way, a copolymer capable of forming an optical film excellent in transparency can be obtained.

Examples of the catalyst for ring-opening polymerization that can be suitably used for producing the cyclic olefin polymer used in the present invention include:
(I) A catalyst described in Olefin Metathesis and Metathesis Polymerization (KJIVIN, JCMOL, Academic Press 1997) is preferably used. Examples of such a catalyst include (a) at least one selected from compounds of W, Mo, Re, V and Ti, and (b) an alkali metal element (for example, Li, Na, K), alkaline earth. Group metal elements (eg, Mg, Ca), Group 12 elements (eg, Zn, Cd, Hg), Group 13 elements (eg, B, Al), Group 14 elements (eg, Si, Sn, Pd) And a metathesis catalyst comprising a combination with at least one selected from those having at least one of the element-carbon bond or the element-hydrogen bond. In order to enhance the activity of the catalyst, the additive (c) described later may be added.
As other catalysts,
(II) A metathesis catalyst composed of a transition metal-carbene complex or a metallacyclobutane complex of Groups 4 to 8 of the periodic table can be used.
The catalysts (I) and (II) may be used in combination.

  The molecular weight of the cyclic olefin polymer used in the present invention can be adjusted by adjusting the polymerization temperature, the type of catalyst, the type of solvent, etc., but the molecular weight regulator is used as a reaction system for ring-opening copolymerization. It is preferable to adjust by coexisting. As the molecular weight regulator, for example, ethylene, propene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene and other α-olefins and styrene are preferable. Of these, 1-butene and 1-hexene are particularly preferred. These molecular weight regulators can be used singly or in combination of two or more. The amount of the molecular weight regulator used is usually 0.005 to 0.6 mol, preferably 0.02 to 0.5 mol, per mol of all monomers.

  Examples of the solvent used in the ring-opening copolymerization reaction (that is, a solvent that dissolves a monomer, a ring-opening polymerization catalyst, a molecular weight regulator, etc.) include alkanes such as pentane, hexane, heptane, octane, nonane, and decane. ; Cycloalkanes such as cyclohexane, cycloheptane, cyclooctane, decalin, norbornane; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene; chlorobutane, bromohexane, methylene chloride, dichloroethane, hexamethylene dibromide, chlorobenzene , Compounds such as halogenated alkanes such as chloroform and tetrachloroethylene, aryl halides; saturated carboxylic acid esters such as ethyl acetate, n-butyl acetate, iso-butyl acetate and methyl propionate; dibutyl ether, tetrahydro Emissions, include ethers such as dimethoxyethane, aromatic hydrocarbons are preferred among these. These can be used singly or in combination of two or more. The use amount of the solvent for the ring-opening polymerization reaction is such that the weight ratio of “solvent: total monomer” is usually 1: 1 to 10: 1, preferably 1: 1 to 5: 1. Is desirable.

  The temperature of the monomer solution when adding the catalyst is preferably 30 to 200 ° C, more preferably 50 to 180 ° C. When the temperature is lower than 30 ° C, the yield of the polymer may be lowered, and when it exceeds 200 ° C, it may be difficult to control the molecular weight.

The reaction time for carrying out the ring-opening copolymerization reaction is usually 0.1 to 10 hours, preferably 0.1 to 9 hours, more preferably 0.1 to 8 hours.
A ring-opening copolymer obtained by ring-opening copolymerization of each cyclic olefin-based monomer has an olefinic unsaturated bond in the molecule and has problems such as heat-resistant coloring. The olefinically unsaturated bond is preferably hydrogenated, but a known method can be applied to the hydrogenation reaction. For example, the catalysts, solvents, temperature conditions, and the like described in JP-A-63-218726, JP-A-1-132626, JP-A-1-240517, JP-A-2-10221, and the like are applied. The ring-opening polymerization reaction and the hydrogenation reaction can be carried out.

  The hydrogenation rate of the olefinically unsaturated bond of the cyclic olefin polymer is usually 80 mol% or more, preferably 90 mol% or more, more preferably 95 mol% or more. In addition, as above-mentioned, the hydrogenation reaction in this invention is with respect to the olefinic unsaturated bond in a molecule | numerator, and when the cyclic olefin type polymer used by this invention has an aromatic group, the aromatic group concerned is Since it may act advantageously in optical characteristics such as refractive index and heat resistance, hydrogenation is not necessarily required.

  When the cyclic olefin polymer according to the present invention is used for molding, additives such as known antioxidants and ultraviolet absorbers are used for improving heat resistance and light resistance within a range not impairing the effects of the present invention. May be used. For example, at least one compound selected from the group consisting of the following phenol-based compounds, thiol-based compounds, sulfide-based compounds, disulfide-based compounds, and phosphorus-based compounds may be added in an amount of 0. By adding 01 to 10 parts by weight, the heat deterioration resistance can be improved.

  Examples of phenolic compounds include triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) proonate], 1,6-hexanediol-bis [3- (3,5-di- -T-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -3,5-triazine, penta Erythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4- Hydroxyphenyl) propionate], octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], N, N-hexamethylenebis 3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) ) Benzene, tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, 3,9-bis [2- [3- (3-t-butyl-4-hydroxy-5- Methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane, and the like. Preferably, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,3,5-trimethyl-2,4,6-tris (3,5-di-t- Butyl-4-hydroxybenzyl) benzene, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], particularly preferably octadecyl-3- (3 5-di-t-butyl-4-hydroxyphenyl) propionate] and the like.

  Examples of thiol compounds include alkyl mercaptans such as t-dodecyl mercaptan and hexyl mercaptan, 2-mercaptobenzimidazole, 2-mercapto-6-methylbenzimidazole, 1-methyl-2- (methylmercapto) benzimidazole, 2-mercapto. -1-methylbenzimidazole, 2-mercapto-4-methylbenzimidazole, 2-mercapto-5-methylbenzimidazole, 2-mercapto-5,6-dimethylbenzimidazole, 2- (methylmercapto) benzimidazole, 1- Examples include methyl-2- (methylmercapto) benzimidazole, 2-mercapto-1,3-dimethylbenzimidazole, mercaptoacetic acid, and the like.

  Examples of sulfide compounds include 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thiobis (4-methyl-6-t- Butylphenol), 2,4-bis (n-octylthiomethyl) -6-methylphenol, dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-thiodipropionate, distearyl 3,3'- Examples thereof include thiodipropionate, pentaerythrityltetrakis (3-laurylthiopropionate), and ditridecyl 3,3′-thiodipropionate.

  Disulfide compounds include bis (4-chlorophenyl) disulfide, bis (2-chlorophenyl) disulfide, bis (2,5-dichlorophenyl) disulfide, bis (2,4,6-trichlorophenyl) disulfide, bis (2-nitro Phenyl) disulfide, ethyl 2,2′-dithiodibenzoate, bis (4-acetylphenyl) disulfide, bis (4-carbamoylphenyl) disulfide, 1,1′-dinaphthyl disulfide, 2,2′-dinaphthyl disulfide, 1,2′-dinaphthyl disulfide, 2,2′-bis (1-chlorodinaphthyl) disulfide, 1,1′-bis (2-chloronaphthyl) disulfide, 2,2′-bis (1-cyanonaphthyl) Disulfide, 2,2'-bis (1-acetylnaphthyl) disulfi , And the like dilauryl-3,3'-thiodipropionate.

  Examples of phosphorus compounds include tris (4-methoxy-3,5-diphenyl) phosphite, tris (nonylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite, bis (2,6 -Di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, and the like.

  Further, benzophenone compounds such as 2,4-dihydroxybenzophenone and 2-hydroxy-4-methoxybenzophenone, benzotriazole compounds such as N- (benzyloxycarbonyloxy) benzotriazole, 2-ethyloxanilide, 2-ethyl By adding 0.01 to 3 parts by weight, preferably 0.05 to 2 parts by weight of an oxanilide-based compound such as -2'-ethoxyoxanilide to 100 parts by weight of the copolymer, light resistance is improved. Can be improved.

In addition, these compounds which are additives may be used individually by 1 type, and may be used in combination.
Moreover, you may add another additive to the cyclic olefin polymer of this invention according to the characteristic of the target molded object. For example, for the purpose of obtaining a colored molded article, a colorant such as a dye or a pigment may be added, and a leveling agent may be added to improve the smoothness of the resulting molded article. . Examples of the leveling agent include a fluorine-based nonionic surfactant, a special acrylic resin leveling agent, and a silicone leveling agent.

Method for Producing Molded Body and Optical Injection Molded Body The optical injection molded body of the present invention is formed by injection molding the above-mentioned cyclic olefin polymer. Specifically, it is obtained by injection molding a pellet made of the above cyclic olefin polymer.
It is preferable that the cyclic olefin polymer used in the present invention removes water and oxygen components dissolved by a known method in advance before injection molding. At this time, a known drying device such as a hot air dryer, a dehumidifying dryer, a nitrogen circulating dryer, a dehumidifying nitrogen circulating dryer, or a vacuum dryer is used. Among these dryers, it is preferable to use a vacuum dryer or a dryer that circulates an inert gas such as nitrogen because a molded product having hue uniformity is easily obtained.
Although a drying temperature and drying time are not specifically limited, Usually, it is dried at Tg-100 degreeC-Tg-20 degreeC for 2 to 6 hours normally.

The injection molding machine used for injection molding is not particularly limited. For example, the cylinder method is an in-line method, a pre-plastic method; the drive method is hydraulic, electric, hybrid; the mold clamping method is direct pressure, and toggle Formula: Examples of the injection direction include a horizontal type and a vertical type. Further, the mold clamping method may be one that can be injection-compressed. Cylinder diameter and clamping force are determined by the shape of the target molded body. Generally, it is preferable to increase the clamping force when the projected area of the molded body is large, and increase the cylinder diameter when the capacity of the molded body is large. It is preferable.
When the cylinder is an in-line type, the screw shape such as compression ratio, length / diameter ratio, subflight presence, etc. can be selected as appropriate, and the screw surface is known such as chromium, titanium, nitride, carbon, etc. The coating may be applied. Further, a mechanism for controlling the rotation and pressure of the screw may be provided in order to improve the stability of measurement and injection operation. Moreover, it is preferable from a viewpoint that a molded object can be obtained stably that pressure reduction is carried out in the cylinder and the hopper which stores a resin composition, or a cylinder and a hopper are sealed with inert gas, such as nitrogen.
The molded body of the present invention is manufactured using a mold having a known material or structure. Such a mold has a cavity corresponding to the shape of the molded body. Examples of preferable materials for the mold include ordinary carbon steel, stainless steel, and known alloys based on these, and the surface of the mold is subjected to quenching treatment, known coating with chromium, titanium, diamond, or the like. Metal plating for processing or pattern processing with nickel-based metal, copper alloy or the like may be applied.
In addition, when forming a pattern on the surface of the molded body for the purpose of collecting light or preventing reflection, a known method such as an electric discharge machine or a cutting machine is applied to the metal coating surface or metal plating surface of the mold or the stamper surface. The pattern may be formed directly by a processing machine, or the pattern may be formed by a method such as electroforming.
At the time of injection molding, a method of reducing the pressure in the cavity of the mold or an injection compression method is preferably used in order to reduce warping of the molded body and stable continuous molding.
When injection molding is performed by reducing the pressure inside the cavity of the mold, the degree of reduced pressure is a gauge pressure, preferably −0.08 MPa or less, more preferably −0.09 MPa or less, and particularly preferably −0.1 MPa or less. . When the above range is exceeded, the degree of reduced pressure is insufficient, and a molded article excellent in light transmittance and light diffusibility may not be obtained.
The degree of vacuum in the above range is achieved using a known method such as a vacuum pump. It is preferable to use a known sealing material such as an O-ring around the cavity or the ejector mechanism, and vacuum grease or the like may be used as long as no impurities are mixed into the molded body. In addition, the suction port for connecting to a decompression device such as a vacuum pump may be provided at any location in the mold, but is usually provided at the ejector mechanism, the end of the sprue and runner, the nested structure, etc. It is done. In addition, the vacuum suction sequence may be controlled by an electromagnetic valve or the like in conjunction with the opening and closing of the mold, may be operated at all times, and a method that allows the inside of the mold cavity to have a desired degree of decompression when filling with molten resin If it is, it will not be restrict | limited in particular.
When injection molding is performed by reducing the pressure inside the mold cavity, the injection delay time is usually set in order to inject the molten resin with the cavity closed and reduced pressure. The injection delay time depends on the capacity of the vacuum pump used and the cavity size, but is usually about 0.5 to 3 seconds.
On the other hand, in the injection compression molding method, the cavity interval is set to 1.5 to 20 times the thickness of the molded body, molten resin is injected into the gap, and the resin pressure measured on the cylinder side is 200 to 2, What is necessary is just to compress the molded object surface in a metal mold | die, hold | maintaining in the range of 000 kgf / cm < ² >, and narrow the space | interval of a cavity.
Further, the mold core is set to a movable state by setting the mold core to 1.1 to 10 times the thickness of the molded body, and molten resin is injected into the mold core. You may compress at 0.01 mm / sec-1 mm / sec.
A known molding machine is used for these injection compression molding methods.
Other conditions for injection molding are not particularly limited, but the cylinder temperature is usually 260 to 350 ° C., and the mold temperature is usually Tg-1 based on the glass transition temperature Tg of the cyclic olefin polymer. It is -Tg-40 degreeC, Preferably it is the range of Tg-5-Tg-25 degreeC. The injection speed varies depending on the size of the molded product of the present invention and the cylinder size of the molding machine. For example, when the cylinder diameter is 28 mm, it is usually 80 mm / sec or more, preferably 90 to 250 mm / sec. In the holding pressure, it is preferable to appropriately adjust to the minimum pressure and time that can maintain the shape of the molded body.
Furthermore, a gas vent mechanism may be provided around the lens cavity for the purpose of preventing carbonization of the resin due to high temperature due to compression of the gas component in the mold and condensation of the volatile component staying in the mold. . Usually, the thickness of the gas vent is formed to a depth of 50 to 150 nm. The gas vent may be provided in a part of the cavity, but is preferably formed on the entire surface except the gate portion. Moreover, you may form such a gas vent in the gate part of a metal mold | die, or a runner part.

Next, the method of the present invention will be specifically described by way of examples, but the present invention is not limited to these examples. The copolymers and molded products obtained in Examples and Comparative Examples were evaluated by the following methods.
<Glass transition temperature (Tg)>
Using a DSC6200 manufactured by Seiko Instruments Inc., the rate of temperature increase was measured at 20 ° C. per minute under a nitrogen stream. For the glass transition temperature (Tg), the differential peak scanning calorie maximum peak temperature (point A) and the temperature of −20 ° C. from the maximum peak temperature (point B) are plotted on the differential scanning calorimetry curve, and the point B is the starting point. It was determined as the intersection of the tangent on the baseline and the tangent starting from point A.
<Melt flow rate (MFR)>
Based on JIS K7210, MFR at a load of 98 N and 260 ° C. was measured.
<Weight average molecular weight and molecular weight distribution>
Weight average molecular weight (Mw) and molecular weight distribution (Mw / Mn) in terms of polystyrene using gel permeation chromatography (GPC, manufactured by Tosoh Corporation, trade name: HLC-8020), using tetrahydrofuran (THF) as a solvent. Was measured.
<Elongation at break>
Using a test piece molded by injection molding, the elongation at break of the resin was measured by the method of ASTM D638.
<Melt flow rate (MFR)>
Using a test piece molded by injection molding, MFR at 260 ° C. and 10 kg load was measured according to JIS K7210. If MFR is 40 or more, since it is excellent in heat fluidity, it can be said that it is a polymer excellent in moldability.

<Example 1>
23.5 parts by weight of dicyclopentadiene as the monomer (1) and 8-methyl-8-carboxymethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene 75.5 parts by weight, 1 part by weight of 2-norbornene as the other monomer, 14.7 parts by weight of 1-hexene as the molecular weight regulator, and 150 parts by weight of toluene as the solvent The reaction vessel was purged with nitrogen and heated to 107 ° C. To this, 0.40 parts by weight of a toluene solution of triethylaluminum (0.6 mol / l) and 1.8 parts by weight of a toluene solution of methanol-modified WCl ₆ (0.025 mol / l) are added and reacted at 107 ° C. for 1 hour. As a result, a ring-opened polymer was obtained.
Ru [4-CH ₃ (CH ₂ ) ₄ C ₆ H ₄ CO ₂ ] H (CO) [P (C ₆ H ₅ ) _3, which is a hydrogenation reaction catalyst, is added to 360 parts by weight of the obtained ring-opening polymer solution. 0.04 part by weight was added, the hydrogen gas pressure was adjusted to 9 to 10 MPa, and the reaction was performed at a temperature of 160 to 165 ° C. for 3 hours. After completion of the reaction, the resulting product was precipitated in a large amount of methanol to obtain a hydrogenated product [weight average molecular weight (Mw) = 45900, molecular weight distribution (Mw / Mn) = 2.8]. This hydrogenated product was vacuum-dried to obtain a cyclic olefin polymer. It was 140 degreeC when the glass transition temperature (Tg) of the cyclic olefin polymer was measured.
The obtained cyclic olefin polymer (1) was melt-kneaded using a twin-screw extruder, then extruded onto a strand, cooled with water, and then pellets were obtained through a feeder ruler. The obtained pellets were vacuum-dried with a dryer at 100 ° C. for 2 hours, and then injection-molded with an injection molding machine (SG75M-S (cylinder diameter: 28 mm, mold clamping: 75 ton) manufactured by Sumitomo Heavy Industries), and 80 mm × 60 mm. A test piece of × 3.2 mm was produced. The injection molding speed was 100 mm / sec, the cylinder temperature was Tg + 140 to 160 ° C. of the resin, and the mold temperature was Tg−10 to −20 ° C. of the resin. Using the obtained test piece, elongation at break and MFR were evaluated. The results are shown in Table 1.

<Example 2>
23.5 parts by weight of dicyclopentadiene as the monomer (1) and 8-methyl-8-carboxymethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 75.5 parts by weight, 1 part by weight of 2-norbornene as the other monomer, 13.4 parts by weight of 1-hexene as the molecular weight regulator, and 150 parts by weight of toluene as the solvent. The reaction vessel was purged with nitrogen and heated to 107 ° C. To this, 0.40 parts by weight of a toluene solution of triethylaluminum (0.6 mol / l) and 1.8 parts by weight of a toluene solution of methanol-modified WCl ₆ (0.025 mol / l) are added and reacted at 107 ° C. for 1 hour. As a result, a ring-opened polymer was obtained.
Ru [4-CH ₃ (CH ₂ ) ₄ C ₆ H ₄ CO ₂ ] H (CO) [P (C ₆ H ₅ ) _3, which is a hydrogenation reaction catalyst, is added to 360 parts by weight of the obtained ring-opening polymer solution. 0.04 part by weight was added, the hydrogen gas pressure was adjusted to 9 to 10 MPa, and the reaction was performed at a temperature of 160 to 165 ° C. for 3 hours. After completion of the reaction, the resulting product was precipitated in a large amount of methanol to obtain a hydrogenated product [weight average molecular weight (Mw) = 52100, molecular weight distribution (Mw / Mn) = 2.9]. This hydrogenated product was vacuum-dried to obtain a cyclic olefin polymer. It was 140 degreeC when the glass transition temperature (Tg) of the cyclic olefin polymer was measured.
A test piece was prepared and evaluated in the same manner as in Example 1 except that the obtained cyclic olefin polymer was used. The results are also shown in Table 1.

<Example 3>
23.5 parts by weight of dicyclopentadiene as the monomer (1) and 8-methyl-8-carboxymethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene, 75.5 parts by weight, 1 part by weight of 2-norbornene as the other monomer, 16.8 parts by weight of 1-hexene as the molecular weight regulator, and 150 parts by weight of toluene as the solvent. The reaction vessel was purged with nitrogen and heated to 107 ° C. To this, 0.40 parts by weight of a toluene solution of triethylaluminum (0.6 mol / l) and 1.8 parts by weight of a toluene solution of methanol-modified WCl ₆ (0.025 mol / l) are added and reacted at 107 ° C. for 1 hour. As a result, a ring-opened polymer was obtained.
Ru [4-CH ₃ (CH ₂ ) ₄ C ₆ H ₄ CO ₂ ] H (CO) [P (C ₆ H ₅ ) _3, which is a hydrogenation reaction catalyst, is added to 360 parts by weight of the obtained ring-opening polymer solution. 0.04 part by weight was added, the hydrogen gas pressure was adjusted to 9 to 10 MPa, and the reaction was performed at a temperature of 160 to 165 ° C. for 3 hours. After completion of the reaction, the resulting product was precipitated in a large amount of methanol to obtain a hydrogenated product [weight average molecular weight (Mw) = 40000, molecular weight distribution (Mw / Mn) = 2.9]. This hydrogenated product was vacuum-dried to obtain a cyclic olefin polymer. It was 139 degreeC when the glass transition temperature (Tg) of the cyclic olefin polymer was measured.
A test piece was prepared and evaluated in the same manner as in Example 1 except that the obtained cyclic olefin polymer was used. The results are also shown in Table 1.

<Example 4>
40 parts by weight of dicyclopentadiene as the monomer (1) and 8-methyl-8-carboxymethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene 60 parts by weight, 1-hexene 14.1 parts by weight as a molecular weight regulator and 150 parts by weight toluene as a solvent were added to a nitrogen-substituted reaction vessel and heated to 107 ° C. To this, 0.40 parts by weight of a toluene solution of triethylaluminum (0.6 mol / l) and 1.8 parts by weight of a toluene solution of methanol-modified WCl ₆ (0.025 mol / l) are added and reacted at 107 ° C. for 1 hour. As a result, a ring-opened polymer was obtained.
Ru [4-CH ₃ (CH ₂ ) ₄ C ₆ H ₄ CO ₂ ] H (CO) [P (C ₆ H ₅ ) _3, which is a hydrogenation reaction catalyst, is added to 360 parts by weight of the obtained ring-opening polymer solution. 0.04 part by weight was added, the hydrogen gas pressure was adjusted to 9 to 10 MPa, and the reaction was performed at a temperature of 160 to 165 ° C. for 3 hours. After completion of the reaction, the resulting product was precipitated in a large amount of methanol to obtain a hydrogenated product [weight average molecular weight (Mw) = 55000, molecular weight distribution (Mw / Mn) = 3.2]. This hydrogenated product was vacuum-dried to obtain a cyclic olefin polymer. It was 135 degreeC when the glass transition temperature (Tg) of the cyclic olefin type polymer was measured.
A test piece was prepared and evaluated in the same manner as in Example 1 except that the obtained cyclic olefin polymer was used. The results are also shown in Table 1.

<Example 5>
35 parts by weight of dicyclopentadiene as the monomer (1) and 8-methyl-8-carboxymethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene 65 parts by weight, 16.0 parts by weight of 1-hexene as a molecular weight regulator and 150 parts by weight of toluene as a solvent were added to a nitrogen-substituted reaction vessel and heated to 107 ° C. To this, 0.40 parts by weight of a toluene solution of triethylaluminum (0.6 mol / l) and 1.8 parts by weight of a toluene solution of methanol-modified WCl ₆ (0.025 mol / l) are added and reacted at 107 ° C. for 1 hour. As a result, a ring-opened polymer was obtained.
Ru [4-CH ₃ (CH ₂ ) ₄ C ₆ H ₄ CO ₂ ] H (CO) [P (C ₆ H ₅ ) _3, which is a hydrogenation reaction catalyst, is added to 360 parts by weight of the obtained ring-opening polymer solution. 0.04 part by weight was added, the hydrogen gas pressure was adjusted to 9 to 10 MPa, and the reaction was performed at a temperature of 160 to 165 ° C. for 3 hours. After completion of the reaction, the resulting product was precipitated in a large amount of methanol to obtain a hydrogenated product [weight average molecular weight (Mw) = 42000, molecular weight distribution (Mw / Mn) = 2.8]. This hydrogenated product was vacuum-dried to obtain a cyclic olefin polymer. It was 133 degreeC when the glass transition temperature (Tg) of the cyclic olefin polymer was measured.
A test piece was prepared and evaluated in the same manner as in Example 1 except that the obtained cyclic olefin polymer was used. The results are also shown in Table 1.

<Comparative Example 1>
Monomer (1) was not used, and 8-methyl-8-carboxymethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene 89 parts by weight, 11 parts by weight of 2-norbornene as the other monomer, 16.8 parts by weight of 1-hexene as the molecular weight regulator, and 150 parts by weight of toluene as the solvent And heated to 80 ° C. To this, 0.20 parts by weight of a toluene solution of triethylaluminum (0.6 mol / l) and 0.89 parts by weight of a toluene solution of methanol-modified WCl ₆ (0.025 mol / l) are added and reacted at 80 ° C. for 1 hour. As a result, a ring-opened polymer was obtained.
To 360 parts by weight of the obtained ring-opening polymer solution, 0.04 part by weight of RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ as a hydrogenation reaction catalyst was added, and the hydrogen gas pressure was 9 to 10 MPa. And reacted at a temperature of 160 to 165 ° C. for 3 hours. After completion of the reaction, the resulting product was precipitated in a large amount of methanol to obtain a hydrogenated product [weight average molecular weight (Mw) = 49700, molecular weight distribution (Mw / Mn) = 3.3]. This hydrogenated product was vacuum-dried to obtain a cyclic olefin polymer. The glass transition temperature (Tg) of the cyclic olefin polymer was measured and found to be 130 ° C.
A test piece was prepared and evaluated in the same manner as in Example 1 except that the obtained cyclic olefin polymer was used. The results are also shown in Table 1.

<Comparative example 2>
23.5 parts by weight of dicyclopentadiene as the monomer (1) and 8-methyl-8-carboxymethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] -3-dodecene 75.5 parts by weight, 1 part by weight of 2-norbornene as the other monomer, 9.2 parts by weight of 1-hexene as the molecular weight regulator, and 150 parts by weight of toluene as the solvent The reaction vessel was purged with nitrogen and heated to 107 ° C. To this, 0.40 parts by weight of a toluene solution of triethylaluminum (0.6 mol / l) and 1.8 parts by weight of a toluene solution of methanol-modified WCl ₆ (0.025 mol / l) are added and reacted at 107 ° C. for 1 hour. As a result, a ring-opened polymer was obtained.
Ru [4-CH ₃ (CH ₂ ) ₄ C ₆ H ₄ CO ₂ ] H (CO) [P (C ₆ H ₅ ) _3, which is a hydrogenation reaction catalyst, is added to 360 parts by weight of the obtained ring-opening polymer solution. 0.04 part by weight was added, the hydrogen gas pressure was adjusted to 9 to 10 MPa, and the reaction was performed at a temperature of 160 to 165 ° C. for 3 hours. After completion of the reaction, the resulting product was precipitated in a large amount of methanol to obtain a hydrogenated product [weight average molecular weight (Mw) = 58500, molecular weight distribution (Mw / Mn) = 2.7]. This hydrogenated product was vacuum-dried to obtain a cyclic olefin polymer. It was 144 degreeC when the glass transition temperature (Tg) of the cyclic olefin type polymer was measured.
A test piece was prepared and evaluated in the same manner as in Example 1 except that the obtained cyclic olefin polymer was used. The results are also shown in Table 1.

Claims (3)

The repeating unit represented by the following formula (1) is 20 to 50% by weight with respect to 100% by weight of all repeating units, and the repeating unit represented by the following formula (2) is 50 to 50% with respect to 100% by weight of all repeating units. A cyclic olefin polymer having 80% by weight and having a polystyrene-reduced weight average molecular weight of 35,000 to 55,000 as determined by gel permeation chromatography is molded by injection molding. Method.

(In Formula (2), R < ¹ > -R < ⁴ > is respectively independently a hydrogen atom, a halogen atom, a C1-C10 hydrocarbon group, or a polar group, provided that at least one of R < ¹ > -R < ⁴ >. Is a polar group, and any two of R ^{1 to} R ⁴ may be bonded to each other to form a monocyclic or polycyclic structure, and m is 0 or 1.) The method for producing a molded article according to claim 1, wherein the cyclic olefin polymer has a polystyrene-reduced weight average molecular weight of 35,000 to 55,000 as determined by gel permeation chromatography. The repeating unit represented by the following formula (1) is 20 to 50% by weight with respect to 100% by weight of all repeating units, and the repeating unit represented by the following formula (2) is 50 to 50% with respect to 100% by weight of all repeating units. An optical injection molded article comprising a cyclic olefin polymer having 80% by weight and having a polystyrene-reduced weight average molecular weight of 35,000 to 55,000 as determined by gel permeation chromatography.

(In Formula (2), R < ¹ > -R < ⁴ > is respectively independently a hydrogen atom, a halogen atom, a C1-C10 hydrocarbon group, or a polar group, provided that at least one of R < ¹ > -R < ⁴ >. Is a polar group, and any two of R ^{1 to} R ⁴ may be bonded to each other to form a monocyclic or polycyclic structure, and m is 0 or 1.)