Patent Description:
A hydrogenated ring-opening polymer of dicyclopentadiene or the like is a cycloolefin polymer that exhibits excellent transparency, low birefringence, excellent formability (processability), and the like, and is used as a material that can be applied to various applications such as optical applications.

However, a hydrogenated ring-opening polymer of dicyclopentadiene or the like is normally obtained in the form of an amorphous polymer that has an atactic structure with random tacticity, and may exhibit insufficient heat resistance, mechanical strength, solvent resistance, and the like depending on the application.

In order to improve the performance of such a hydrogenated ring-opening polymer, it has been proposed to provide a hydrogenated ring-opening polymer of dicyclopentadiene or the like with crystallinity.

For example, Patent Literature <NUM> discloses that a ring-opening polymer having crystallinity is obtained by subjecting dicyclopentadiene to ring-opening polymerization using a polymerization catalyst that mainly includes a Group <NUM> transition metal compound (i.e., a compound that includes a transition metal that belongs to Group <NUM> in the periodic table) that is substituted with a specific substituent, and a hydrogenated ring-opening polymer having crystallinity is obtained by hydrogenating the carbon-carbon double bonds included in the ring-opening polymer using a hydrogenation catalyst. Patent Literature <NUM> discloses that a ring-opening polymer having syndiotacticity is obtained by subjecting dicyclopentadiene to ring-opening polymerization using a polymerization catalyst that mainly includes a Group <NUM> transition metal compound that includes an imido ligand, and a syndiotactic hydrogenated ring-opening polymer having crystallinity in which the ratio of racemo diads is <NUM>% or more, is obtained by hydrogenating the carbon-carbon double bonds included in the ring-opening polymer using a hydrogenation catalyst.

The melting point of these crystalline hydrogenated dicyclopentadiene ring-opening polymers is <NUM> to <NUM>. However, the glass transition temperature of a hydrogenated dicyclopentadiene ring-opening polymer is about <NUM> irrespective of whether the hydrogenated dicyclopentadiene ring-opening polymer is crystalline or amorphous. Therefore, when a crystalline hydrogenated dicyclopentadiene ring-opening polymer is heated to a temperature equal to or higher than <NUM>, the amorphous domain of the resin undergoes thermal relaxation. Accordingly, a formed article produced using a crystalline hydrogenated dicyclopentadiene ring-opening polymer may change in mechanical strength or heat resistance at about <NUM>, whereby an increase in coefficient of linear expansion may occur, or deflection may occur even under a low load, for example.

Patent Literature <NUM> discloses that a ring-opening polymer having syndiotacticity is obtained by subjecting tetracyclododecene to ring-opening polymerization using a specific ring-opening polymerization catalyst that mainly includes a Group <NUM> transition metal compound that includes an imido ligand, and an amorphous hydrogenated tetracyclododecene ring-opening polymer is obtained by hydrogenating the carbon-carbon double bonds included in the ring-opening polymer. Patent Literature <NUM> discloses that, when tungsten hexachloride is used as the polymerization catalyst, the resulting hydrogenated tetracyclododecene ring-opening polymer has a melting point (<NUM>), but does not have a glass transition temperature (i.e., a semi-crystalline resin is obtained).

Patent Literatures <NUM> to <NUM> and Non-Patent Literature <NUM> also disclose the production of hydrogenated ring-opened polymers.

The inventor conducted studies with regard to the semi-crystalline hydrogenated tetracyclododecene ring-opening polymer disclosed in Patent Literature <NUM>. When the resin was melted, and rapidly cooled (solidified) to form a resin formed article, a glass transition temperature and exotherm due to cold crystallization were observed when the thermal properties of the resulting resin were measured using a differential scanning calorimeter. When the resulting resin formed article was subjected to wide-angle X-ray diffraction analysis, only an amorphous halo was observed (i.e., a peak attributed to a crystal was not observed) (i.e., it was found that the crystallinity was lost). Specifically, when an atactic hydrogenated tetracyclododecene ring-opening polymer has been melted, crystallization does not occur even when the molten polymer is cooled to the room temperature due to a significant decrease in crystallization rate. Therefore, the resulting product exhibits poor heat resistance and processability, and has low industrial value as a material.

The invention was conceived in order to solve the above problems. An object of the invention is to provide a hydrogenated tetracyclododecene-based ring-opening polymer that has a high melting point and a high glass transition temperature, has crystallinity even after being subjected to a thermal history due to melt forming or the like, and exhibits excellent heat resistance and excellent processability, and a method for producing the same.

The inventor conducted extensive studies in order to solve the above problem. As a result, the inventor found that a hydrogenated tetracyclododecene-based ring-opening polymer that includes a repeating unit (A) derived from tetracyclododecene in a ratio of <NUM> wt% or more based on the total amount of repeating units, wherein the ratio of meso diads in the repeating unit (A) is <NUM>% or more, has a high melting point and a high glass transition temperature, has crystallinity even after being subjected to a thermal history including rapid cooling due to melt forming or the like, and exhibits excellent heat resistance and excellent processability. The inventor also found that the melting point and the glass transition temperature of a hydrogenated tetracyclododecene-based ring-opening copolymer can be adjusted to the desired values while maintaining the mechanical strength up to the desired temperature, by appropriately selecting the weight ratio of a repeating unit derived from tetracyclododecene to a repeating unit derived from a monomer other than tetracyclododecene as long as the hydrogenated tetracyclododecene-based ring-opening copolymer has crystallinity. These findings have led to the completion of the invention.

One aspect of the invention relates to a hydrogenated tetracyclododecene-based ring-opening polymer comprising a repeating unit (A) derived from tetracyclododecene having a content of endo-anti stereoisomer of <NUM>% or more in a ratio of <NUM> wt% or more based on a total amount of repeating units, the hydrogenated tetracyclododecene-based ring-opening polymer being obtained by hydrogenating <NUM>% or more of main-chain carbon-carbon double bonds of a tetracyclododecene-based ring-opening polymer,.

It is preferable that the hydrogenated tetracyclododecene-based ring-opening polymer further comprises a repeating unit derived from dicyclopentadiene.

It is preferable that the hydrogenated tetracyclododecene-based ring-opening polymer further comprises a repeating unit derived from norbornene.

It is preferable that the hydrogenated tetracyclododecene-based ring-opening polymer has a number average molecular weight (Mn) calculated from the ratio of the number of hydrogen atoms present at the terminals of the ring-opening polymer chain to the number of hydrogen atoms present in the ring-opening polymer chain excluding the terminals in the <NUM>H-NMR spectrum of the tetracyclododecene-based ring-opening polymer of <NUM>,<NUM> to <NUM>,<NUM>.

It is preferable that the hydrogenated tetracyclododecene-based ring-opening polymer has a glass transition temperature measured at a heating rate of <NUM>/min of an amorphous sample prepared by melting the ring-opening polymer at a high temperature, and instantaneously introducing the molten ring-opening polymer into liquid nitrogen to rapidly cool the ring-opening polymer using a differential scanning calorimeter of <NUM> or more.

Another aspect of the invention relates to a method for producing the hydrogenated tetracyclododecene-based ring-opening polymer, the method comprising subjecting a tetracyclododecene-based monomer comprising tetracyclododecene having a content of endo-anti stereoisomer of <NUM>% or more in a ratio of <NUM> wt% or more based on the total amount of monomer to ring-opening polymerization using a compound represented by the following formula (<NUM>) or a compound represented by the following formula (<NUM>) and n-butyllithium as a polymerization catalyst to obtain a tetracyclododecene-based ring-opening polymer, and hydrogenating the main-chain carbon-carbon double bonds of the tetracyclododecene-based ring-opening polymer using hydrogen and a hydrogenation catalyst,
<CHM>.

wherein M represents a transition metal atom that belongs to Group <NUM> in the periodic table, L represents an imido ligand that is unsubstituted, or substituted with an alkyl group having <NUM> to <NUM> carbon atoms or a substituted or unsubstituted aryl group having <NUM> to <NUM> carbon atoms, or an oxo ligand, each of R<NUM> to R<NUM> independently represents a hydrogen atom, an alkyl group having <NUM> to <NUM> carbon atoms, or a substituted or unsubstituted aryl group having <NUM> to <NUM> carbon atoms, provided that R<NUM> to R<NUM> are optionally bonded to each other to form a ring, X represents a halogen atom, n represents an integer from <NUM> to <NUM>, and m represents (<NUM>-n),
<CHM>.

wherein M, L, and X are the same as defined above, each of R<NUM> to R<NUM> independently represents a hydrogen atom, an alkyl group having <NUM> to <NUM> carbon atoms, or a substituted or unsubstituted aryl group having <NUM> to <NUM> carbon atoms, provided that R<NUM> to R<NUM> are optionally bonded to each other to form a ring, p represents <NUM> or <NUM>, q represents (<NUM>-2p), and r represents <NUM> or <NUM>.

The hydrogenated tetracyclododecene-based ring-opening polymer according to one aspect of the invention has a high melting point and a high glass transition temperature, has crystallinity even after being subjected to a thermal history including rapid cooling due to melt forming or the like, and exhibits excellent heat resistance and excellent processability.

Since the hydrogenated tetracyclododecene-based ring-opening polymer according to one aspect of the invention has an isotactic structure, and has a high crystallization rate, the hydrogenated tetracyclododecene-based ring-opening polymer may suitably be used as a forming material, a textile material, and a film-forming material used in various applications.

The hydrogenated tetracyclododecene-based ring-opening polymer according to one aspect of the invention can be designed to have the desired melting point and the desired glass transition temperature while maintaining the mechanical strength up to the desired temperature, by appropriately selecting the weight ratio of a repeating unit derived from tetracyclododecene to a repeating unit derived from a monomer other than tetracyclododecene.

The method according to one aspect of the invention can efficiently produce the hydrogenated tetracyclododecene-based ring-opening polymer according to one aspect of the invention.

A hydrogenated tetracyclododecene-based ring-opening polymer and a production method according to the exemplary embodiments of the invention are described in detail below.

A hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention includes a repeating unit (A) derived from tetracyclododecene in a ratio of <NUM> wt% or more (preferably <NUM> wt% or more, and more preferably <NUM> wt% or more) based on the total amount of repeating units, the ratio of meso diads in the repeating unit (A) being <NUM>% or more.

The repeating unit (A) derived from tetracyclododecene is the repeating unit represented by the following formula (<NUM>). The repeating unit represented by the formula (<NUM>) is obtained by hydrogenating the main-chain carbon-carbon double bond included in a tetracyclododecene unit obtained by subjecting tetracyclododecene represented by the following formula (<NUM>) to ring-opening polymerization.

Examples of an additional repeating unit other than the repeating unit (A) derived from tetracyclododecene that may be included in the hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention, include a repeating unit derived from a monocyclic cycloalkene, a repeating unit derived from norbomene or a derivative thereof, a repeating unit derived from dicyclopentadiene or a derivative thereof, a repeating unit derived from a tetracyclododecene derivative (excluding a repeating unit derived from tetracyclododecene), a repeating unit derived from hexacycloheptadecene or a derivative thereof, and the like. These additional repeating units other than the repeating unit (A) derived from tetracyclododecene are obtained by hydrogenating the main-chain carbon-carbon double bond included in a monomer unit obtained by subjecting an additional monomer that is copolymerizable with tetracyclododecene (through ring-opening polymerization) to ring-opening polymerization.

A repeating unit derived from dicyclopentadiene or a derivative thereof, and a repeating unit derived from norbomene or a derivative thereof, are preferable as the additional repeating unit, and a repeating unit derived from dicyclopentadiene and a repeating unit derived from norbomene are more preferable as the additional repeating unit.

When the hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention includes a repeating unit derived from dicyclopentadiene or a derivative thereof, it is preferable that the hydrogenated tetracyclododecene-based ring-opening polymer include a repeating unit derived from tetracyclododecene in a ratio of <NUM> wt% or more, and include a repeating unit derived from dicyclopentadiene or a derivative thereof in a ratio of <NUM> wt% or less. It is more preferable that the hydrogenated tetracyclododecene-based ring-opening polymer include a repeating unit derived from tetracyclododecene in a ratio of <NUM> wt% or more, and include a repeating unit derived from dicyclopentadiene or a derivative thereof in a ratio of <NUM> wt% or less. It is particularly preferable that the hydrogenated tetracyclododecene-based ring-opening polymer include a repeating unit derived from tetracyclododecene in a ratio of <NUM> wt% or more, and include a repeating unit derived from dicyclopentadiene or a derivative thereof in a ratio of <NUM> wt% or less. If the ratio of a repeating unit derived from tetracyclododecene is lower than the above range, and the ratio of a repeating unit derived from dicyclopentadiene or a derivative thereof is higher than the above range, it may be difficult to obtain a hydrogenated tetracyclododecene-based ring-opening polymer that has a high melting point and a high glass transition temperature.

When the hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention includes a repeating unit derived from norbomene or a derivative thereof, it is preferable that the hydrogenated tetracyclododecene-based ring-opening polymer include a repeating unit derived from tetracyclododecene in a ratio of <NUM> wt% or more, and include a repeating unit derived from norbomene or a derivative thereof in a ratio of <NUM> wt% or less. It is more preferable that the hydrogenated tetracyclododecene-based ring-opening polymer include a repeating unit derived from tetracyclododecene in a ratio of <NUM> wt% or more, and include a repeating unit derived from norbomene or a derivative thereof in a ratio of <NUM> wt% or less. It is particularly preferable that the hydrogenated tetracyclododecene-based ring-opening polymer include a repeating unit derived from tetracyclododecene in a ratio of <NUM> wt% or more, and include a repeating unit derived from norbomene or a derivative thereof in a ratio of <NUM> wt% or less. If the ratio of a repeating unit derived from tetracyclododecene is lower than the above range, and the ratio of a repeating unit derived from norbomene or a derivative thereof is higher than the above range, it may be difficult to obtain a hydrogenated tetracyclododecene-based ring-opening polymer that has a high melting point and a high glass transition temperature.

The hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention has a specific tacticity since the carbon atoms indicated by (<NUM>, <NUM>) in the formula (<NUM>) are asymmetric carbon atoms.

The hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention is an isotactic polymer that has isotacticity, wherein the ratio of meso diads is <NUM>% or more, preferably <NUM>% or more, and more preferably <NUM>% or more.

If the ratio of meso diads is less than <NUM>%, the crystallinity of the hydrogenated tetracyclododecene-based ring-opening polymer may decrease to a large extent, and the characteristics (e.g., high melting point and processability) of the hydrogenated tetracyclododecene-based ring-opening polymer may be impaired.

The ratio of meso diads can be calculated by analyzing the <NUM>C-NMR spectrum of the hydrogenated tetracyclododecene-based ring-opening polymer. Specifically, the ratio of meso diads can be determined by quantitatively determining the spectrum of the carbon atoms of the hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention that are indicated by (<NUM>, <NUM>) in the formula (<NUM>). More specifically, the <NUM>C-NMR spectrum of the carbon atoms indicated by (<NUM>, <NUM>) included in the repeating unit represented by the formula (<NUM>) is measured at <NUM> using an o-dichlorobenzene-d<NUM>/trichlorobenzene mixed solvent, and the ratio of meso diads to racemo diads is determined based on the intensity ratio of the signal at <NUM> ppm attributed to meso diads to the signal at <NUM> ppm attributed to racemo diads.

The number average molecular weight (Mn) of the hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention is <NUM> to <NUM>,<NUM>,<NUM>, preferably <NUM>,<NUM> to <NUM>,<NUM>, and more preferably <NUM>,<NUM> to <NUM>,<NUM>. If the number average molecular weight (Mn) of the hydrogenated tetracyclododecene-based ring-opening polymer is too low, the hydrogenated tetracyclododecene-based ring-opening polymer may exhibit low mechanical strength. If the number average molecular weight (Mn) of the hydrogenated tetracyclododecene-based ring-opening polymer is too high, it may be difficult to form (mold) the hydrogenated tetracyclododecene-based ring-opening polymer. Note that the number average molecular weight (Mn) of the hydrogenated tetracyclododecene-based ring-opening polymer is almost equal to the number average molecular weight of the unhydrogenated tetracyclododecene-based ring-opening polymer.

The melting point of the hydrogenated tetracyclododecene-based ring-opening polymer is <NUM> or more, and preferably <NUM> or more. If the melting point of the hydrogenated tetracyclododecene-based ring-opening polymer is less than <NUM>, processability may deteriorate since the crystallinity of the resin is low. The upper limit of the melting point of the hydrogenated tetracyclododecene-based ring-opening polymer is not particularly limited, but may be about <NUM>.

The glass transition temperature of the hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention is preferably <NUM> or more, and more preferably <NUM> or more. If the glass transition temperature of the hydrogenated tetracyclododecene-based ring-opening polymer is less than <NUM>, the resin may exhibit low heat resistance. For example, the resin may have a low deflection temperature under load. The upper limit of the glass transition temperature of the hydrogenated tetracyclododecene-based ring-opening polymer is not particularly limited, but may be about <NUM>.

The hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention may be produced by an arbitrary method. For example, the hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention may preferably be produced by the following production method according to one embodiment of the invention.

A method for producing a hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention includes subjecting a tetracyclododecene-based monomer to ring-opening polymerization using the compound represented by the formula (<NUM>) (hereinafter may be referred to as "compound (<NUM>)") or the compound represented by the formula (<NUM>) (hereinafter may be referred to as "compound (<NUM>)") as a polymerization catalyst to obtain a tetracyclododecene-based ring-opening polymer (hereinafter referred to as "step (I)"), and hydrogenating the main-chain carbon-carbon double bonds of the tetracyclododecene-based ring-opening polymer using hydrogen and a hydrogenation catalyst (hereinafter referred to as "step (II)").

In the step (I), the tetracyclododecene-based monomer including tetracyclododecene in a ratio of <NUM> wt% or more (preferably <NUM> wt% or more, and more preferably <NUM> wt% or more) based on the total amount of monomer is subjected to ring-opening polymerization using the compound (<NUM>) or the compound (<NUM>) as a polymerization catalyst to obtain a tetracyclododecene-based ring-opening polymer.

It is known that tetracyclododecene that is used as the monomer includes an endo-anti stereoisomer, an endo-syn stereoisomer, an exo-anti stereoisomer, and an exo-syn stereoisomer. Tetracyclododecene normally includes an endo-anti stereoisomer and an exo-syn stereoisomer as the main components, and the content of an endo-syn stereoisomer and an exo-anti stereoisomer is equal to or less than the detection limit when determined by spectral analysis.

It is preferable that tetracyclododecene have high optical purity in order to achieve the object of the invention. It is particularly preferable that tetracyclododecene have a high endo-anti stereoisomer content. According to the invention, the endo-anti stereoisomer content is <NUM>% or more. If the endo-anti stereoisomer content is less than <NUM>%, the crystallinity of the hydrogenated tetracyclododecene-based ring-opening polymer may decrease to a large extent, and the characteristics (e.g., high melting point and high glass transition temperature) of the hydrogenated tetracyclododecene-based ring-opening polymer may be impaired.

A monomer other than tetracyclododecene that may be included in the tetracyclododecene-based monomer is not particularly limited as long as the object of the invention is not impaired. Examples of the monomer other than tetracyclododecene include a cycloalkene, dicyclopentadiene and a derivative thereof, norbomene and a derivative thereof, a tetracyclododecene derivative, hexacycloheptadecene and a derivative thereof, and the like. Among these, dicyclopentadiene and a derivative thereof, and norbomene and a derivative thereof are preferable, and dicyclopentadiene and norbomene are more preferable.

These monomers may be used either alone or in combination.

Examples of the cycloalkene include cyclopentene, cyclohexene, cycloheptane, and the like.

Examples of dicyclopentadiene and a derivative thereof include dicyclopentadiene, tricyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM>]dec-<NUM>-ene (obtained by saturating the double bond of the <NUM>-membered ring included in dicyclopentadiene), tricyclo[<NUM>. <NUM><NUM>,<NUM>. <NUM>]undec-<NUM>-ene, and the like.

Examples of norbomene and a derivative thereof include unsubstituted norbomene and a norbomene derivative that is substituted with an alkyl group, such as <NUM>-methylnorbomene, <NUM>-ethylnorbomene, <NUM>-butylnorbomene, <NUM>-hexylnorbomene, <NUM>-decylnorbomene, <NUM>-cyclohexylnorbomene, and <NUM>-cyclopentylnorbomene; a norbomene derivative that is substituted with an alkenyl group, such as <NUM>-ethylidenenorbornane, <NUM>-vinylnorbomene, <NUM>-propenylnorbomene, <NUM>-cyclohexenylnorbomene, and <NUM>-cyclopentenylnorbornene; a norbomene derivative that is substituted with an aromatic ring, such as <NUM>-phenylnorbornene;.

Examples of a tetracyclododecene derivative include a tetracyclododecene derivative that is substituted with an alkyl group, such as <NUM>-methyltetracyclododecene, <NUM>-ethyltetracyclododecene, <NUM>-cyclohexyltetracyclododecene, and <NUM>-cyclopentyltetracyclododecene; a tetracyclododecene derivative that includes a double bond outside the ring, such as <NUM>-methylidynetetracyclododecene, <NUM>-ethylidenetetracyclododecene, <NUM>-vinyltetracyclododecene, <NUM>-propenyltetracyclododecene, <NUM>-cyclohexenyltetracyclododecene, and <NUM>-cyclopentenyltetracyclododecene;.

Examples of hexacycloheptadecene and a derivative thereof include unsubstituted hexacycloheptadecene and a hexacycloheptadecene derivative that is substituted with an alkyl group, such as <NUM>-methylhexacycloheptadecene, <NUM>-ethylhexacycloheptadecene, <NUM>-cyclohexylhexacycloheptadecene, and <NUM>-cyclopentylhexacycloheptadecene; a hexacycloheptadecene derivative that includes a double bond outside the ring, such as <NUM>-methylidynehexacycloheptadecene, <NUM>-ethylidenehexacycloheptadecene, <NUM>-vinylhexacycloheptadecene, <NUM>-propenylhexacycloheptadecene, <NUM>-cyclohexenylhexacycloheptadecene, and <NUM>-cyclopentenylhexacycloheptadecene; a hexacycloheptadecene derivative that is substituted with an aromatic ring, such as <NUM>-phenylhexacycloheptadecene;.

When implementing the production method according to one embodiment of the invention, the compound (<NUM>) or the compound (<NUM>) is used as the polymerization catalyst.

In the formulas (<NUM>) and (<NUM>), M represents a transition metal atom that belongs to Group <NUM> in the periodic table. It is preferable that M be a tungsten atom or a molybdenum atom from the viewpoint of improving the activity of the polymerization catalyst.

L represents an imido ligand that is unsubstituted, or substituted with an alkyl group having <NUM> to <NUM> carbon atoms or a substituted or unsubstituted aryl group having <NUM> to <NUM> carbon atoms, or an oxo ligand.

The alkyl group having <NUM> to <NUM> carbon atoms that may substitute the imido ligand may be linear, branched, or cyclic. Specific examples of the alkyl group having <NUM> to <NUM> carbon atoms include a linear or branched alkyl group having <NUM> to <NUM> carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a t-butyl group, and a pentyl group; a cycloalkyl group having <NUM> to <NUM> carbon atoms, such as a cyclohexyl group and an adamantyl group; and the like.

Examples of the substituted or unsubstituted aryl group having <NUM> to <NUM> carbon atoms that may substitute the imido ligand include a phenyl group, and a monosubstituted to pentasubstituted phenyl group that is substituted with a substituent at at least one of positions <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. A substituent that may substitute the aryl group is not particularly limited. Examples of the substituent include an alkyl group having <NUM> to <NUM> carbon atoms, such as a methyl group, an ethyl group, and an isopropyl group; an aryl group such as a phenyl group; a halogen atom such as a fluorine atom, a chlorine atom, and a bromine atom; an alkoxy group having <NUM> to <NUM> carbon atoms, such as a methoxy group and an ethoxy group; an amino group; an imino group; and the like.

Each of R<NUM> to R<NUM> independently represents a hydrogen atom, an alkyl group having <NUM> to <NUM> carbon atoms, or a substituted or unsubstituted aryl group having <NUM> to <NUM> carbon atoms.

Examples of the alkyl group having <NUM> to <NUM> carbon atoms and the substituted or unsubstituted aryl group having <NUM> to <NUM> carbon atoms include those mentioned above in connection with the imido ligand.

R<NUM> to R<NUM> and R<NUM> to R<NUM> are optionally bonded to each other to form a ring.

X represents a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. When a plurality of X are present, the plurality of X are either identical to or different from each other. It is preferable that all of X be a chlorine atom.

n represents an integer from <NUM> to <NUM>. It is preferable that n be <NUM> or <NUM>, and more preferably <NUM>, from the viewpoint of controlling the tacticity of a repeating unit obtained by hydrogenating the main-chain double bonds of a ring-opening polymer obtained by subjecting tetracyclododecene or the like to ring-opening polymerization.

p represents <NUM> or <NUM>, and is preferably <NUM>.

r represents <NUM> or <NUM>, and is preferably <NUM>.

Examples of the compound (<NUM>) and the compound (<NUM>) (hereinafter may be referred to as "Group <NUM> transition metal compound") used in connection with one embodiment of the invention include an oxymolybdenum compound such as tetraphenoxyoxymolybdenum(VI), tetrakis(<NUM>,<NUM>-dimethylphenoxy)oxymolybdenum(VI), tetrakis(<NUM>,<NUM>-diisopropylphenoxy)oxymolybdenum(VI), bis{<NUM>,<NUM>'-methylenebis(<NUM>-methyl-<NUM>-t-butylphenoxy)}oxymolybdenum(VI), bis(<NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-dioxy)oxymolybdenum(VI), bis{<NUM>,<NUM>'-di(t-butyl)-<NUM>,<NUM>',<NUM>,<NUM>'-tetramethyl-<NUM>,<NUM>'-biphenoxy}oxymolybdenum(VI), bis{<NUM>,<NUM>'-diphenyl-<NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-dioxy}oxymolybdenum(VI), {<NUM>,<NUM>'-di(t-butyl)-<NUM>,<NUM>',<NUM>,<NUM>'-tetramethyl-<NUM>,<NUM>'-biphenoxy}oxymolybdenum(VI) dichloride, bis(<NUM>,<NUM>-dimethylphenoxy)oxymolybdenum(VI) dichloride, bis(<NUM>,<NUM>-diisopropylphenoxy)oxymolybdenum(VI) dichloride, (<NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-dioxy)oxymolybdenum(VI) dichloride, tris(<NUM>,<NUM>-dimethylphenoxy)oxymolybdenum(VI) chloride, and triskis(<NUM>,<NUM>-diisopropylphenoxy)oxymolybdenum(VI) chloride;.

The Group <NUM> transition metal compound used in connection with one embodiment of the invention may be synthesized using an arbitrary method. For example, the compound represented by the formula (<NUM>) wherein L is an imido ligand may be obtained by reacting an oxyhalide of a transition metal that belongs to Group <NUM> in the periodic table, or an imidohalide of a transition metal that belongs to Group <NUM> in the periodic table, with a metal salt of unsubstituted or substituted phenol (phenol metal salt). An oxychloride of a transition metal that belongs to Group <NUM> in the periodic table, or an imidochloride of a transition metal that belongs to Group <NUM> in the periodic table, is preferably used as the oxyhalide of a transition metal that belongs to Group <NUM> in the periodic table, or the imidohalide of a transition metal that belongs to Group <NUM> in the periodic table, from the viewpoint of reactivity and versatility.

Examples of the oxychloride of a transition metal that belongs to Group <NUM> in the periodic table, include oxymolybdenum tetrachloride, oxytungsten tetrachloride, and the like.

Examples of the imidochloride of a transition metal that belongs to Group <NUM> in the periodic table, include phenylimidomolybdenum tetrachloride, <NUM>,<NUM>-diisopropylphenylimidomolybdenum tetrachloride, cyclohexylimidomolybdenum tetrachloride, adamantylimidomolybdenum tetrachloride, phenylimidotungsten tetrachloride, <NUM>,<NUM>-diisopropylphenylimidotungsten tetrachloride, cyclohexylimidotungsten tetrachloride, ethylimidotungsten tetrachloride, adamantylimidotungsten tetrachloride, and the like.

Note that the imidohalide of a transition metal that belongs to Group <NUM> in the periodic table may be obtained by reacting an oxytungsten tetrahalide with a substituted isocyanate (when M is tungsten), or reacting a molybdenum tetrahalide with a substituted azide (when M is molybdenum).

The oxyhalide of a transition metal that belongs to Group <NUM> in the periodic table, or the imidohalide of a transition metal that belongs to Group <NUM> in the periodic table, may be a compound in which <NUM> equivalent of an electron-donating base is coordinated. Examples of the electron-donating base include diethyl ether, dibutyl ether, tetrahydrofuran, pyridine, <NUM>,<NUM>-lutidine, and triethylamine.

A phenol alkali metal salt is preferable as the phenol metal salt. Specific examples of the phenol metal salt include phenoxylithium, <NUM>,<NUM>-dimethylphenoxylithium, <NUM>,<NUM>-diisopropylphenoxylithium, <NUM>,<NUM>'-methylenebis-(<NUM>-methyl-<NUM>-t-butylphenoxy)lithium, (<NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-dioxy)dilithium, <NUM>,<NUM>'-di(t-butyl)-<NUM>,<NUM>',<NUM>,<NUM>'-tetramethyl-<NUM>,<NUM>'-biphenoxydilithium, <NUM>,<NUM>'-diphenyl-<NUM>,<NUM>'-binaphthyl-<NUM>,<NUM>'-dioxylithium, and the like.

According to the invention, the polymerization catalyst includes n-butyllithium in addition to the Group <NUM> transition metal compound. When the polymerization catalyst includes n-butyllithium cocatalyst, the polymerization catalyst exhibits improved activity.

The n-butyllithium is normally added in an amount of <NUM> to <NUM>-fold mol, preferably <NUM> to <NUM>-fold mol, and more preferably <NUM> to <NUM>-fold mol, based on the center metal of the Group <NUM> transition metal compound. If the n-butyllithium is added in too small an amount, the polymerization activity may not be sufficiently improved. If the n-butyllithium is added in too large an amount, a side reaction may easily occur.

The Group <NUM> transition metal compound may be used in an arbitrary amount. The Group <NUM> transition metal compound is preferably used in such an amount that the molar ratio of the transition metal included in the Group <NUM> transition metal compound to the tetracyclododecene-based monomer is <NUM>:<NUM> to <NUM>:<NUM>,<NUM>,<NUM>, more preferably <NUM>:<NUM> to <NUM>:<NUM>,<NUM>,<NUM>, and particularly preferably <NUM>:<NUM> to <NUM>:<NUM>,<NUM>. If the polymerization catalyst is used in too large an amount, it may be difficult to remove the polymerization catalyst. If the polymerization catalyst is used in too small an amount, sufficient polymerization activity may not be obtained.

The polymerization reaction may be effected in a solvent-free system. Note that it is preferable to effect the polymerization reaction in an organic solvent since the reaction can be advantageously controlled.

The organic solvent is not particularly limited as long as the organic solvent can dissolve or disperse the resulting ring-opening polymer, and is inert to the polymerization reaction. Specific examples of the organic solvent include an aliphatic hydrocarbon-based solvent such as pentane, hexane, and heptane; an alicyclic hydrocarbon-based solvent such as cyclopentane, cyclohexane, methylcyclohexane, dimethylcyclohexane, trimethylcyclohexane, ethylcyclohexane, diethylcyclohexane, decahydronaphthalene, bicycloheptane, tricyclodecane, hexahydroindenecyclohexane, and cyclooctane; an aromatic hydrocarbon-based solvent such as benzene, toluene, and xylene; a halogen-containing aliphatic hydrocarbon-based solvent such as dichloromethane, chloroform, and <NUM>,<NUM>-dichloroethane; a halogen-containing aromatic hydrocarbon-based solvent such as chlorobenzene and dichlorobenzene; a nitrogen-containing hydrocarbon-based solvent such as nitromethane, nitrobenzene, and acetonitrile; an ether-based solvent such as diethyl ether and tetrahydrofuran; an aromatic ether-based solvent such as anisole and phenetole; and the like. Among these, an aromatic hydrocarbon-based solvent, an aliphatic hydrocarbon-based solvent, an alicyclic hydrocarbon-based solvent, an ether-based solvent, and an aromatic ether-based solvent are particularly preferable.

When effecting the polymerization reaction in the organic solvent, the concentration of the tetracyclododecene-based monomer in the reaction system is not particularly limited, but is preferably <NUM> to <NUM> wt%, more preferably <NUM> to <NUM> wt%, and particularly preferably <NUM> to <NUM> wt%. If the concentration of the tetracyclododecene-based monomer is too low, productivity may decrease. If the concentration of the tetracyclododecene-based monomer is too high, the viscosity of the reaction solution may increase to a large extent after completion of the polymerization reaction, and it may be difficult to effect the subsequent hydrogenation reaction.

The polymerization temperature is not particularly limited, but is normally -<NUM> to +<NUM>, and preferably <NUM> to <NUM>. The polymerization time is determined taking account of the reaction scale, but is normally selected within the range from <NUM> minute to <NUM> hours.

When effecting the polymerization reaction, a vinyl compound or a diene compound may be added to the polymerization reaction system in order to adjust the molecular weight of the resulting ring-opening polymer.

The vinyl compound is not particularly limited as long as the vinyl compound is an organic compound that includes a vinyl group. Examples of the vinyl compound include an alpha-olefin such as <NUM>-butene, <NUM>-pentene, <NUM>-hexene, and <NUM>-octene; styrene and a derivative thereof, such as styrene and vinyltoluene; an ether such as ethyl vinyl ether, i-butyl vinyl ether, and allyl glycidyl ether; a halogen-containing vinyl compound such as allyl chloride; an oxygen-containing vinyl compound such as allyl acetate, allyl alcohol, and glycidyl methacrylate; a nitrogen-containing vinyl compound such as acrylamide; a silicon-containing vinyl compound such as vinyltrimethylsilane and vinyltrimethoxysilane; and the like.

Examples of the diene compound include a non-conjugated diene such as <NUM>,<NUM>-pentadiene, <NUM>,<NUM>-hexadiene, <NUM>,<NUM>-hexadiene, <NUM>,<NUM>-heptadiene, <NUM>-methyl-<NUM>,<NUM>-pentadiene, and <NUM>,<NUM>-dimethyl-<NUM>,<NUM>-hexadiene; a conjugated diene such as <NUM>,<NUM>-butadiene, <NUM>-methyl-<NUM>,<NUM>-butadiene, <NUM>,<NUM>-dimethyl-<NUM>,<NUM>-butadiene, <NUM>,<NUM>-pentadiene, and <NUM>,<NUM>-hexadiene; and the like.

The vinyl compound or the diene compound is added in such an amount that a ring-opening polymer having the desired molecular weight can be obtained. The vinyl compound or the diene compound is normally added in a ratio of <NUM> to <NUM> mol% based on the tetracyclododecene-based monomer.

A tetracyclododecene-based ring-opening polymer having isotacticity can be obtained by subjecting the tetracyclododecene-based monomer to a ring-opening (co)polymerization reaction using the Group <NUM> transition metal compound as the polymerization catalyst.

Since the tacticity of the tetracyclododecene-based ring-opening polymer does not change due to the hydrogenation reaction by effecting the hydrogenation reaction as described below, a hydrogenated tetracyclododecene-based ring-opening polymer having isotacticity and crystallinity can be obtained by subjecting the tetracyclododecene-based ring-opening polymer to the hydrogenation reaction. Note that the tetracyclododecene-based ring-opening polymer may be collected from the reaction mixture, and then subjected to the hydrogenation reaction, or the reaction mixture including the tetracyclododecene-based ring-opening polymer may be subjected directly to the hydrogenation reaction.

The number average molecular weight (Mn) of the tetracyclododecene-based ring-opening polymer obtained as described above determined by <NUM>H-NMR is not particularly limited, but is <NUM> to <NUM>,<NUM>,<NUM>, preferably <NUM>,<NUM> to <NUM>,<NUM>, and more preferably <NUM>,<NUM> to <NUM>,<NUM>. The number average molecular weight (Mn) of the tetracyclododecene-based ring-opening polymer is determined as described below. Specifically, the ratio of the number of hydrogen atoms present at the terminals of the polymer chain to the number of hydrogen atoms present in the polymer chain excluding the terminals is calculated based on the <NUM>H-NMR measurement results, and the number average molecular weight of the tetracyclododecene-based ring-opening polymer is calculated based on the calculated ratio. A hydrogenated tetracyclododecene-based ring-opening polymer that exhibits particularly excellent heat resistance and excellent processability can be obtained by subjecting the tetracyclododecene-based ring-opening polymer having a number average molecular weight within the above range to the hydrogenation reaction.

In the step (II), the main-chain carbon-carbon double bonds of the tetracyclododecene-based ring-opening polymer obtained by the step (I) are hydrogenated using hydrogen and the hydrogenation catalyst to obtain the hydrogenated tetracyclododecene-based ring-opening polymer according to one embodiment of the invention.

A hydrogenation catalyst commonly used to hydrogenate an olefin compound may be used as the hydrogenation catalyst. Examples of the hydrogenation catalyst include a hydrogenation catalyst that includes a dicyclopentadienyltitanium halide, a nickel organic carboxylate, a cobalt organic carboxylate, or the like, and an organometallic compound that includes a metal that belongs to Group <NUM>, <NUM>, or <NUM> in the periodic table; a metal catalyst such as nickel, platinum, palladium, ruthenium, or rhenium supported on carbon, silica, diatomaceous earth, or the like, a rhodium metal catalyst, a cobalt complex, a nickel complex, a rhodium complex, and a ruthenium complex; a hydrogenated compound such as lithium aluminum hydride and p-toluenesulfonyl hydrazide; and the like. Among these, a ruthenium compound is preferable since the target product can be obtained in high yield while suppressing isomerization.

Examples of the ruthenium compound include RuHCl(CO)(PPh<NUM>)<NUM>, RuHCl(CO)[P(p-Me-Ph)<NUM>]<NUM>, RuHCl(CO)(PCy<NUM>)<NUM>, RuHCl(CO)[P(n-Bu)<NUM>]<NUM>, RuHCl(CO)[P(i-Pr)<NUM>]<NUM>, RuH<NUM>(CO)(PPh<NUM>)<NUM>, RuH<NUM>(CO)[P(p-Me-Ph)<NUM>]<NUM>, RuH<NUM>(CO)(PCy<NUM>)<NUM>, RuH<NUM>(CO)[P(n-Bu)<NUM>]<NUM>RuH(OCOCH<NUM>)(CO)(PPh<NUM>)<NUM>, RuH(OCOPh)(CO)(PPh<NUM>)<NUM>, RuH(OCOPh-CH<NUM>)(CO)(PPh<NUM>)<NUM>, RuH(OCOPh-OCH<NUM>)(CO)(PPh<NUM>)<NUM>, RuH(OCOPh)(CO)(PCy<NUM>)<NUM>, and the like.

The hydrogenation reaction is normally effected in an inert organic solvent. Examples of the inert organic solvent include an aromatic hydrocarbon such as benzene, toluene, and xylene; an aliphatic hydrocarbon-based solvent such as pentane and hexane; an alicyclic hydrocarbon-based solvent such as cyclohexane and decahydronaphthalene; an ether-based solvent such as tetrahydrofuran and ethylene glycol dimethyl ether; and the like.

In the step (II), hydrogen is added to the system that includes the tetracyclododecene-based ring-opening polymer and the hydrogenation catalyst to hydrogenate the carbon-carbon double bonds included in the tetracyclododecene-based ring-opening polymer.

The hydrogenation temperature is selected taking account of the type of hydrogenation catalyst. The hydrogenation temperature is normally set to -<NUM> to +<NUM>, preferably -<NUM> to +<NUM>, and more preferably from <NUM> to +<NUM>. If the hydrogenation temperature is too low, the reaction rate may decrease to a large extent. If the hydrogenation temperature is too high, a side reaction may occur.

The hydrogen pressure is normally set to <NUM> to <NUM> MPa, preferably <NUM> to <NUM> MPa, and more preferably <NUM> to <NUM> MPa. If the hydrogen pressure is too low, the reaction (hydrogenation) rate may decrease to a large extent. If the hydrogen pressure is too high, it may be necessary to use a reactor that can endure high pressure (i.e., the reaction equipment is limited).

The hydrogenation time is determined taking account of the reaction scale, but is normally set to <NUM> to <NUM> hours.

After completion of the hydrogenation reaction, the resulting hydrogenated tetracyclododecene-based ring-opening polymer is collected using an ordinary method. The residual catalyst may be removed by filtration or the like.

The hydrogenation ratio of the ring-opening polymer achieved by the hydrogenation reaction (i.e., the ratio of main-chain double bonds that have been hydrogenated) is <NUM>% or more, preferably <NUM>% or more, and more preferably <NUM>% or more. The resulting hydrogenated tetracyclododecene-based ring-opening polymer exhibits better heat resistance and processability as the hydrogenation ratio increases.

The hydrogenated tetracyclododecene-based ring-opening polymer may or may not have a specific tacticity as long as the hydrogenated tetracyclododecene-based ring-opening polymer has crystallinity (i.e., has a melting point), and the ratio of meso diads is <NUM>% or more. The hydrogenated tetracyclododecene-based ring-opening polymer obtained using the production method according to one embodiment of the invention normally has isotacticity.

The hydrogenated tetracyclododecene-based ring-opening polymer obtained using the production method according to one embodiment of the invention is a crystalline polymer that has a high melting point and a high glass transition temperature, and rarely shows a decrease in melting point even when heated at a temperature higher than the melting point. Therefore, the crystalline hydrogenated tetracyclododecene-based ring-opening polymer exhibits excellent heat resistance even after being formed by a melt forming process (i.e., exhibits excellent heat resistance and excellent processability), and may particularly suitably be used as a material for producing a formed article for which heat resistance is required. The applications of the formed article produced using the hydrogenated tetracyclododecene-based ring-opening polymer are not particularly limited. Examples of the applications of the formed article include an optical reflector, an insulating material, an optical film, a connector, a food packaging material, a bottle, a pipe, a gear, fibers, a nonwoven fabric, and the like.

The invention is further described below by way of examples. Note that the invention is not limited to the following examples.

The following measurement methods and evaluation methods were used in connection with the examples.

The ratio of the number of hydrogen atoms present at the terminals of the polymer chain to the number of hydrogen atoms present in the polymer chain excluding the terminals was calculated based on the <NUM>H-NMR measurement results, and the number average molecular weight of the tetracyclododecene-based ring-opening polymer was calculated based on the calculated ratio.

The ratio of the number of hydrogen atoms derived from the tetracyclododecene unit to the number of hydrogen atoms derived from the monomer unit other than the tetracyclododecene unit was calculated based on the <NUM>H-NMR measurement results, and the copolymerization compositional ratio (wt%) of the tetracyclododecene-based ring-opening polymer was calculated based on the calculated ratio.

The hydrogenation ratio of the tetracyclododecene-based ring-opening polymer was calculated based on the <NUM>H-NMR measurement results.

The ratio of meso diads to racemo diads in the hydrogenated tetracyclododecene-based ring-opening polymer was determined by subjecting the hydrogenated tetracyclododecene-based ring-opening polymer to <NUM>C-NMR measurement at <NUM> using o-dichlorobenzene-d<NUM>/trichlorobenzene mixed solvent, and calculating the ratio of meso diads to racemo diads based on the intensity ratio of the signal at <NUM> ppm (attributed to meso diads) to the signal at <NUM> ppm (attributed to racemo diads).

The melting point of the hydrogenated tetracyclododecene-based ring-opening polymer was measured using a differential scanning calorimeter (DSC) ("X-DSC7000" manufactured by SII NanoTechnology Inc. ) at a heating rate of <NUM>/min (independently of the thermal history of the resin). A temperature at which the endothermic calorific value was a maximum with respect to the first-order phase transition peak due to crystal melting was taken as the melting point. The glass transition temperature of the hydrogenated tetracyclododecene-based ring-opening polymer was measured by heating an amorphous sample (prepared by melting the resin at a high temperature, and instantaneously introducing the molten resin into liquid nitrogen to rapidly cool the resin) at a heating rate of <NUM>/min using a differential scanning calorimeter (DSC).

The melt-formed sample (see (<NUM>)) was subjected to X-ray diffraction analysis using a wide-angle X-ray diffractometer ("RINT <NUM>" manufactured by Rigaku Corporation) to measure the crystalline peak and the amorphous halo, and the intensity ratio thereof was calculated to determine the degree of crystallinity based on the weight ratio.

The hydrogenated ring-opening polymer was hot-pressed (melt-formed) using a metal die (<NUM>×<NUM>×<NUM>), and cooled at a cooling rate of <NUM>/min to prepare a sample (hereinafter may be referred to as "melt-formed sample"). The sample was immersed in solder at <NUM> for <NUM> seconds, and the presence or absence of deformation was observed with the naked eye. A case where deformation was not observed (i.e., the sample exhibited excellent heat resistance) was evaluated as "Good", and a case where deformation was observed was evaluated as "Bad".

One end of the melt-formed sample subjected to the solder immersion test was placed on a horizontal plane, and the distance between the other end of the sample (in the longitudinal direction) and the horizontal plane was measured, and taken as the curling value (mm). It was determined that the sample exhibited better heat resistance as the curling value decreased.

A glass reactor equipped with a stirrer was charged with <NUM> of a molybdenum oxytetrachloride complex (Mo(=O)Cl<NUM>) and <NUM> of toluene, and the mixture was cooled to -<NUM>. A solution prepared by dissolving <NUM> of <NUM>,<NUM>-dimethylphenoxylithium in <NUM> of toluene was cooled to -<NUM>, and added to the mixture. The resulting mixture was heated to <NUM>, and reacted at <NUM> for <NUM> hours. After completion of the reaction, n-hexane was added to the reaction mixture so that the n-hexane/toluene weight ratio was <NUM>/<NUM>, and a white precipitate was filtered off using Celite. The solvent was completely evaporated from the filtrate to obtain a blue solid (yield: <NUM>%). The blue solid was dissolved in a toluene/n-hexane (=<NUM>/<NUM> (weight ratio)) mixture. The resulting solution was cooled to -<NUM>, and allowed to stand to effect recrystallization to obtain a solid (blue needle-like crystals). The yield of the solid was <NUM> (<NUM>%). The solid was identified by <NUM>H-NMR, <NUM>C-NMR, and elemental analysis to be tetrakis(<NUM>,<NUM>-dimethylphenoxy)oxymolybdenum(VI).

A glass reactor equipped with a stirrer was charged with <NUM> of a phenylimidotungsten tetrachloride diethyl ether complex (W(=NPh)Cl<NUM>(Et<NUM>O)) and <NUM> of diethyl ether, and the mixture was cooled to -<NUM>. A solution prepared by dissolving <NUM> of <NUM>,<NUM>'-di(t-butyl)-<NUM>,<NUM>',<NUM>,<NUM>'-tetramethyl-<NUM>,<NUM>'-biphenoxylithium in <NUM> of diethyl ether was added to the mixture. The resulting mixture was gradually returned to room temperature (<NUM> (hereinafter the same)), and reacted at room temperature for <NUM> hours. After completion of the reaction, diethyl ether was evaporated from the reaction mixture. The residue was dissolved in a toluene/n-hexane (=<NUM>/<NUM> (weight ratio)) mixed solvent, and a white precipitate was filtered off using Celite. The solvent was completely evaporated from the filtrate to obtain a red solid (yield: <NUM>%). The red solid was cooled to -<NUM>, and allowed to stand to effect recrystallization to obtain a solid (red needle-like microcrystals). The yield of the solid was <NUM> (<NUM>%). The solid was identified by <NUM>H-NMR, <NUM>C-NMR, and elemental analysis to be bis{<NUM>,<NUM>'-di(t-butyl)-<NUM>,<NUM>',<NUM>,<NUM>'-tetramethyl-<NUM>,<NUM>'-biphenoxy}phenylimidotungsten(VI).

A glass reactor equipped with a stirrer was charged with <NUM> of a tetrakis(<NUM>,<NUM>-dimethylphenoxy)oxymolybdenum(VI) obtained in Synthesis Example <NUM> and <NUM> of toluene, and the mixture was cooled to -<NUM>. After the addition of a solution prepared by dissolving <NUM> of n-butyllithium in <NUM> of n-hexane to the mixture, the resulting mixture was returned to room temperature, and reacted at room temperature for <NUM> minutes. After the addition of <NUM> of tetracyclododecene (TCD), <NUM> of cyclohexane, and <NUM> of <NUM>-hexene to the reaction mixture, a polymerization reaction was effected at <NUM>. The viscosity of the reaction mixture gradually increased after the start of the polymerization reaction. After <NUM> hours had elapsed from the start of the polymerization reaction, a large quantity of acetone was poured into the reaction mixture to aggregate a precipitate, and the aggregate was filtered off. The aggregate was then washed with methanol, and dried at <NUM> for <NUM> hours under reduced pressure. <NUM> of a ring-opening polymer was thus obtained. The ring-opening polymer had a number average molecular weight of <NUM>,<NUM>.

An autoclave equipped with a stirrer was charged with <NUM> of the ring-opening polymer obtained as described above and <NUM> of cyclohexane. After the addition of a dispersion prepared by dispersing <NUM> of RuHCl(CO)(PPh<NUM>)<NUM> in <NUM> of cyclohexane, a hydrogenation reaction was effected at <NUM> for <NUM> hours under a hydrogen pressure of <NUM> MPa. The reaction mixture was poured into a large quantity of acetone to completely precipitate the resulting hydrogenated ring-opening polymer, which was filtered off. The hydrogenated ring-opening polymer was then washed with methanol, and dried at <NUM> for <NUM> hours under reduced pressure. The hydrogenation ratio of the resulting hydrogenated ring-opening polymer <NUM> was <NUM>% or more, and the ratio of meso diads to racemo diads in the hydrogenated ring-opening polymer was <NUM>:<NUM> (i.e., the hydrogenated ring-opening polymer <NUM> was isotactic).

The hydrogenated ring-opening polymer <NUM> was heated at a heating rate of <NUM>/min using a DSC to measure the melting point. The melting point measured in a state in which the hydrogenated ring-opening polymer <NUM> had not been subjected to a thermal history was <NUM>.

A sample that had been heated to <NUM> (completely melted) in the DSC was introduced into liquid nitrogen in a molten state to prepare a quench-cooled amorphous sample, and the amorphous sample was heated at a heating rate of <NUM>/min. A glass transition temperature was observed at <NUM>.

Next the amorphous sample was heated to <NUM> (completely melted) in the DSC and was cooled to room temperature at a cooling rate of <NUM>/min to solidify the sample, and the solidified sample was heated at a heating rate of <NUM>/min. A peak attributed to cold crystallization was observed to only a small extent during heating, and a melting point was observed at <NUM>.

The hydrogenated ring-opening polymer <NUM> was heated at <NUM> for <NUM> minutes (sufficiently melted), and melt-formed using the specific metal die. The melt-formed product was cooled to room temperature at a cooling rate of <NUM>/min to solidify the melt-formed product to prepare a melt-formed sample. When the melt-formed sample was subjected to wide-angle X-ray diffraction analysis, a sharp peak attributed to crystal diffraction was observed. It was thus confirmed that the melt-formed sample was crystalline. The sharp peak attributed to crystal diffraction and the amorphous halo were subjected to a waveform separation process to calculate the degree of crystallinity (based on weight ratio) of the melt-formed sample. The degree of crystallinity of the melt-formed sample thus calculated was <NUM>%.

When the melt-formed sample was then subjected to DSC analysis, a peak attributed to cold crystallization was observed to only a small extent during heating, and an endothermic peak was observed at <NUM>. It was thus confirmed that the melting point of the crystal included in the melt-formed sample was <NUM>. Therefore, crystallization proceeded to a sufficient extent when the melt-formed product was cooled to room temperature at a cooling rate of <NUM>/min using the specific metal die, and a crystalline resin was obtained. The melt-formed sample was also subjected to the solder immersion test and the curling value measurement process. The results are shown in Table <NUM>.

A glass reactor equipped with a stirrer was charged with <NUM> of bis{<NUM>,<NUM>'-di(t-butyl)-<NUM>,<NUM>',<NUM>,<NUM>'-tetramethyl-<NUM>,<NUM>'-biphenoxy}phenylimidotungsten(VI) obtained in Synthesis Example <NUM> and <NUM> of toluene, and the mixture was cooled to -<NUM>. After the addition of a solution prepared by dissolving <NUM> of n-butyllithium in <NUM> of hexane to the mixture, the resulting mixture was returned to room temperature, and reacted at room temperature for <NUM> minutes. After the addition of <NUM> of tetracyclododecene (TCD), <NUM> of dicyclopentadiene (DCP), <NUM> of cyclohexane, and <NUM> of <NUM>-hexene to the reaction mixture, a polymerization reaction was effected at <NUM>. The viscosity of the mixture gradually increased after the start of the polymerization reaction, and the mixture became slightly cloudy. After <NUM> hours had elapsed from the start of the polymerization reaction, a large quantity of acetone was poured into the reaction mixture to aggregate a precipitate, and the aggregate was filtered off, washed, and dried at <NUM> for <NUM> hours under reduced pressure. <NUM> of a ring-opening polymer was thus obtained. The copolymerization compositional ratio (weight ratio) of tetracyclododecene to dicyclopentadiene in the ring-opening polymer calculated from the <NUM>H-NMR spectrum data was <NUM>:<NUM>, and the number average molecular weight of the ring-opening polymer was <NUM>,<NUM>.

An autoclave equipped with a stirrer was charged with <NUM> of the ring-opening polymer obtained as described above and <NUM> of cyclohexane. After the addition of a dispersion prepared by dispersing <NUM> of RuHCl(CO)(PPh<NUM>)<NUM> in <NUM> of cyclohexane, a hydrogenation reaction was effected at <NUM> for <NUM> hours under a hydrogen pressure of <NUM> MPa. The reaction mixture was poured into a large quantity of acetone to completely precipitate the resulting hydrogenated ring-opening polymer, which was filtered off. The hydrogenated ring-opening polymer was then washed with methanol, and dried at <NUM> for <NUM> hours under reduced pressure. The hydrogenation ratio of the resulting hydrogenated ring-opening polymer <NUM> was <NUM>% or more, and the ratio of meso diads to racemo diads in the repeating unit derived from tetracyclododecene was <NUM>:<NUM>.

The hydrogenated ring-opening polymer <NUM> that had been dried under reduced pressure was heated at <NUM> for <NUM> minutes (sufficiently melted), and melt-formed using the specific metal die. The melt-formed product was cooled to room temperature at a cooling rate of <NUM>/min to solidify the melt-formed product to prepare a melt-formed sample. When the melt-formed sample was subjected to wide-angle X-ray diffraction analysis, a sharp peak attributed to crystal diffraction was observed. It was thus confirmed that the melt-formed sample was crystalline. The sharp peak attributed to crystal diffraction and the amorphous halo were subjected to a waveform separation process to calculate the degree of crystallinity (based on weight ratio) of the melt-formed sample. The degree of crystallinity of the melt-formed sample thus calculated was <NUM>%.

A glass reactor equipped with a stirrer was charged with <NUM> of bis{<NUM>,<NUM>'-di(t-butyl)-<NUM>,<NUM>',<NUM>,<NUM>'-tetramethyl-<NUM>,<NUM>'-biphenoxy}phenylimidotungsten(VI) obtained in Synthesis Example <NUM> and <NUM> of toluene, and the mixture was cooled to -<NUM>. After the addition of a solution prepared by dissolving <NUM> of n-butyllithium in <NUM> of hexane to the mixture, the resulting mixture was returned to room temperature (<NUM>), and reacted at room temperature for <NUM> minutes. After the addition of <NUM> of tetracyclododecene (TCD), <NUM> of norbornene (NB), <NUM> of cyclohexane, and <NUM> of <NUM>-hexene to the reaction mixture, a polymerization reaction was effected at <NUM>. The viscosity of the reaction mixture gradually increased after the start of the polymerization reaction. After <NUM> hours had elapsed from the start of the polymerization reaction, a large quantity of acetone was poured into the reaction mixture to aggregate a precipitate, and the aggregate was filtered off, washed with methanol, and dried at <NUM> for <NUM> hours under reduced pressure. <NUM> of a ring-opening polymer was thus obtained. The copolymerization compositional ratio (weight ratio) of tetracyclododecene to norbomene in the ring-opening polymer calculated from the <NUM>H-NMR spectrum data was <NUM>:<NUM>, and the number average molecular weight of the ring-opening polymer was <NUM>,<NUM>.

An autoclave equipped with a stirrer was charged with <NUM> of the ring-opening polymer obtained as described above and <NUM> of cyclohexane. After the addition of a dispersion prepared by dispersing <NUM> of RuHCl(CO)(PPh<NUM>)<NUM> in <NUM> of cyclohexane, a hydrogenation reaction was effected at <NUM> for <NUM> hours under a hydrogen pressure of <NUM> MPa. The reaction mixture was poured into a large quantity of acetone to completely precipitate the resulting hydrogenated ring-opening polymer, which was filtered off. The hydrogenated ring-opening polymer was then washed with methanol, and dried at <NUM> for <NUM> hours under reduced pressure. The hydrogenation ratio of the resulting hydrogenated ring-opening polymer <NUM> was <NUM>%s or more, and the ratio of meso diads to racemo diads in the repeating unit derived from tetracyclododecene was <NUM>:<NUM>.

The hydrogenated ring-opening polymer <NUM> was heated at a heating rate of <NUM>/min using a DSC to measure the melting point. The melting point measured in a state in which the hydrogenated ring-opening polymer <NUM> had not been subjected to a thermal history was <NUM>. A sample that had been heated to <NUM> (completely melted) in the DSC was introduced into liquid nitrogen in a molten state to prepare a quench-cooled amorphous sample, and the amorphous sample was heated at a heating rate of <NUM>/min. A glass transition temperature was observed at <NUM>. Next the amorphous sample was heated to <NUM> (completely melted) in the DSC and was cooled to room temperature at a cooling rate of <NUM>/min to solidify the sample, and the solidified sample was heated at a heating rate of <NUM>/min. A peak attributed to cold crystallization was observed to only a small extent during heating, and a melting point was observed at <NUM>.

A hydrogenated ring-opening polymer 1r was obtained in the same manner as in Example <NUM>, except that a reaction product of <NUM> of phenylimidotungsten(VI) tetrachloride diethyl ether and <NUM> of diethylaluminum ethoxide was used as the polymerization catalyst instead of the reaction product of tetrakis(<NUM>,<NUM>-dimethylphenoxy)oxymolybdenum(VI) and n-butyllithium. The hydrogenation ratio of the resulting hydrogenated ring-opening polymer 1r was <NUM>% or more, and the ratio of meso diads to racemo diads was <NUM>:<NUM> (i.e., the hydrogenated ring-opening polymer 1r was syndiotactic).

The glass transition temperature of the hydrogenated ring-opening polymer 1r measured as described above was <NUM>, and a melting point was not observed even when the hydrogenated ring-opening polymer 1r was heated to <NUM>. A sample that had been heated to <NUM> (completely melted) in the DSC was introduced into liquid nitrogen in a molten state to prepare a quench-cooled amorphous sample, and the amorphous sample was heated at a heating rate of <NUM>/min. A glass transition temperature was observed at <NUM>, and a melting point was not observed. Next the amorphous sample was heated to <NUM> (completely melted) in the DSC and was cooled to room temperature at a cooling rate of <NUM>/min to solidify the sample, and the solidified sample was heated at a heating rate of <NUM>/min. A glass transition temperature was observed at <NUM> during heating, and a melting point was not observed.

The hydrogenated ring-opening polymer 1r that had been dried under reduced pressure was heated at <NUM> for <NUM> minutes (sufficiently melted), and melt-formed using the specific metal die. The melt-formed product was cooled to room temperature at a cooling rate of <NUM>/min to solidify the melt-formed product to prepare a melt-formed sample. When the melt-formed sample was subjected to wide-angle X-ray diffraction analysis, a peak attributed to crystal diffraction was not observed, and only an amorphous halo was observed. Specifically, the degree of crystallinity (based on weight ratio) of the melt-formed sample was <NUM>%. When the melt-formed sample was subjected to DSC analysis, a peak attributed to cold crystallization during heating and a peak attributed to crystal melting were not observed, and only a glass transition temperature was observed at <NUM>. It was thus confirmed that the syndiotactic hydrogenated tetracyclododecene-based ring-opening polymer in which the ratio of meso diads was <NUM>%, was amorphous independently of the thermal history and the forming conditions. The melt-formed sample was also subjected to the solder immersion test and the curling value measurement process. The results are shown in Table <NUM>. Note that the curling value (mm) could not be measured due to significant deformation.

A hydrogenated ring-opening polymer 2r was obtained in the same manner as in Example <NUM>, except that a reaction product of <NUM> of tungsten(VI) hexachloride and <NUM> of diethylaluminum ethoxide was used as the polymerization catalyst instead of the reaction product of tetrakis(<NUM>,<NUM>-dimethylphenoxy)oxymolybdenum(VI) and n-butyllithium. The hydrogenation ratio of the resulting hydrogenated ring-opening polymer 2r was <NUM>% or more, and the ratio of meso diads to racemo diads was <NUM>:<NUM> (i.e., the hydrogenated ring-opening polymer 2r was atactic).

The hydrogenated ring-opening polymer 2r was heated at a heating rate of <NUM>/min using a DSC to measure the melting point. The melting point measured in a state in which the hydrogenated ring-opening polymer 2r had not been subjected to a thermal history was <NUM>. A sample that had been heated to <NUM> (completely melted) in the DSC was introduced into liquid nitrogen in a molten state to prepare a quench-cooled amorphous sample. When the amorphous sample was heated at a heating rate of <NUM>/min, a glass transition temperature was observed at <NUM>. When the amorphous sample was further heated, an exothermic peak attributed to phase transition was observed at <NUM>. This suggests that cold crystallization occurred. Next the amorphous sample was heated to <NUM> (completely melted) in the DSC and was cooled to room temperature at a cooling rate of <NUM>/min to solidify the sample, and the solidified sample was heated at a heating rate of <NUM>/min. A glass transition temperature was observed at <NUM>. An exothermic peak attributed to cold crystallization was observed at <NUM>, and an endothermic peak attributed to crystal melting was observed at <NUM>. The exothermic peak and the endothermic peak were observed at the same calorific value (absolute value).

The hydrogenated ring-opening polymer that had been dried under reduced pressure was heated at <NUM> for <NUM> minutes (sufficiently melted), and melt-formed using the specific metal die. The melt-formed product was cooled to room temperature at a cooling rate of <NUM>/min to solidify the melt-formed product to prepare a melt-formed sample. When the melt-formed sample was subjected to wide-angle X-ray diffraction analysis, a peak attributed to crystal diffraction was not observed, and only an amorphous halo was observed. Specifically, the degree of crystallinity (based on weight ratio) of the melt-formed sample was <NUM>%.

When the melt-formed sample was subjected to DSC analysis, a glass transition temperature was observed at <NUM> during heating. A peak attributed to cold crystallization was observed at <NUM>, and a peak attributed to crystal melting was observed at <NUM>. These peaks were observed at the same calorific value (absolute value). It was thus confirmed that the atactic hydrogenated tetracyclododecene-based ring-opening polymer in which the ratio of meso diads was <NUM>%, was not crystallized under the forming conditions in which the melt-formed product was cooled to room temperature at a cooling rate of <NUM>/min using the specific metal die, and the melt-formed sample was amorphous. Therefore, the melt-formed sample did not have a melting point. The melt-formed sample was also subjected to the solder immersion test and the curling value measurement process. The results are shown in Table <NUM>.

A hydrogenated ring-opening polymer 3r was obtained in the same manner as in Example <NUM>, except that a reaction product of <NUM> of <NUM>,<NUM>-diisopropylphenylimidotungsten(VI) tetrachloride diethyl ether and <NUM> of diethylaluminum ethoxide was used as the polymerization catalyst instead of the reaction product of tetrakis(<NUM>,<NUM>-dimethylphenoxy)oxymolybdenum(VI) and n-butyllithium. The hydrogenation ratio of the resulting hydrogenated ring-opening polymer 3r was <NUM>% or more, and the ratio of meso diads to racemo diads was <NUM>:<NUM> (i.e., the hydrogenated ring-opening polymer 3r was atactic).

The hydrogenated ring-opening polymer 3r was heated at a heating rate of <NUM>/min using a DSC to measure the melting point. The melting point measured in a state in which the hydrogenated ring-opening polymer 3r had not been subjected to a thermal history was <NUM>. A sample that had been heated to <NUM> (completely melted) in the DSC was introduced into liquid nitrogen in a molten state to prepare a quench-cooled amorphous sample, and the amorphous sample was heated at a heating rate of <NUM>/min. A glass transition temperature was observed at <NUM>. When the amorphous sample was further heated, an exothermic peak attributed to phase transition was observed at <NUM>. This suggests that cold crystallization occurred. Next the amorphous sample was heated to <NUM> (completely melted) in the DSC and was cooled to room temperature at a cooling rate of <NUM>/min to solidify the sample, and the solidified sample was heated at a heating rate of <NUM>/min. A glass transition temperature was observed at <NUM>. An exothermic peak attributed to cold crystallization was observed at <NUM>, and an endothermic peak attributed to crystal melting was observed at <NUM>. These peaks were observed at the same calorific value (absolute value).

The hydrogenated ring-opening polymer 3r was heated at <NUM> for <NUM> minutes (sufficiently melted), and melt-formed using the specific metal die. The melt-formed product was cooled to room temperature at a cooling rate of <NUM>/min to solidify the melt-formed product to prepare a melt-formed sample. When the melt-formed sample was subjected to wide-angle X-ray diffraction analysis, a peak attributed to crystal diffraction was not observed, and only an amorphous halo was observed. Specifically, the degree of crystallinity (based on weight ratio) of the melt-formed sample was <NUM>%.

As is clear from the results shown in Table <NUM>, the hydrogenated tetracyclododecene-based ring-opening polymers of Examples <NUM> to <NUM> in which the ratio of meso diads was <NUM>% or more, had a high melting point (after melting) and a high glass transition temperature, had a high crystallization rate (after melting), and exhibited excellent heat resistance (after melting).

The syndiotactic hydrogenated tetracyclododecene-based ring-opening polymer of Comparative Example <NUM> in which the ratio of meso diads was less than <NUM>%, was substantially amorphous, and exhibited poor heat resistance (after melting). The atactic hydrogenated tetracyclododecene-based ring-opening polymers of Comparative Examples <NUM> and <NUM> did not exhibit crystallinity (after melting) when normal forming conditions were used (since the crystallization rate (after melting) was low), and exhibited poor heat resistance (after melting).

Claim 1:
A hydrogenated tetracyclododecene-based ring-opening polymer comprising a repeating unit (A) derived from tetracyclododecene having a content of endo-anti stereoisomer of <NUM>% or more in a ratio of <NUM> wt% or more based on a total amount of repeating units, the hydrogenated tetracyclododecene-based ring-opening polymer being obtained by hydrogenating <NUM>% or more of main-chain carbon-carbon double bonds of a tetracyclododecene-based ring-opening polymer,
wherein the ratio of meso diads in the repeating unit (A) determined based on the intensity ratio of the signal at <NUM> ppm attributed to meso diads to the signal at <NUM> ppm attributed to racemo diads in the <NUM>C-NMR spectrum measured at <NUM> using o-dichlorobenzene-d<NUM>/trichlorobenzene mixed solvent is <NUM>% or more, and
the melting point measured as a temperature at which an endothermic calorific value is a maximum with respect to the first-order phase transition peak due to crystal melting using a differential scanning calorimeter at a heating rate of <NUM>/min is <NUM> or more.