CN114981327A

CN114981327A - Olefin copolymer and film

Info

Publication number: CN114981327A
Application number: CN202180009752.2A
Authority: CN
Inventors: 柏女洋平; 十河健二; 古贺隆志
Original assignee: Sumitomo Chemical Co Ltd
Current assignee: Sumitomo Chemical Co Ltd
Priority date: 2020-01-29
Filing date: 2021-01-25
Publication date: 2022-08-30
Also published as: KR20220134591A; WO2021153478A1

Abstract

The present invention addresses the problem of providing an olefin copolymer that enables the production of a molded article having a low coefficient of linear expansion, and a film comprising the olefin copolymer. The olefin copolymer comprises a monomer unit (1) derived from at least one selected from the group consisting of ethylene and linear alpha-olefins having 3-20 carbon atoms, and a monomer unit (2) derived from a cyclic olefin represented by the formula (I), wherein the olefin isThe hydrocarbon copolymer satisfies requirements (a) to (c). (a) The glass transition temperature is 220 ℃ or higher. (b) The ratio (Mw/Mn) of the weight average molecular weight Mw in terms of polystyrene to the number average molecular weight Mn in terms of polystyrene, as measured by gel permeation chromatography, is 2.2 or less. (c) The refractive index is less than 1.540. [ chemical formula 1]

Description

Olefin copolymer and film

Technical Field

The present invention relates to an olefin copolymer and a film containing the olefin copolymer.

Background

Conventionally, a transition metal catalyst called a so-called metallocene catalyst has been used for polymerization of olefins such as ethylene and propylene. The following effects are known: by using a metallocene catalyst, a polymer having properties different from those of the conventional polymers can be produced, and a large amount of polymer can be produced with a very small amount of catalyst.

The use of such metallocene catalysts has also been proposed for cyclic olefins represented by norbornene. For example, patent document 1 discloses a method for polymerizing a cyclic olefin and ethylene and/or an α -olefin using a catalyst containing a specific transition metal complex as one component. According to the method of patent document 1, an olefin copolymer obtained by polymerizing cyclic olefins at a high conversion rate can be obtained with a very small amount of catalyst.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 9-183809

Disclosure of Invention

Problems to be solved by the invention

In order to provide a molded article having excellent dimensional stability, it is necessary to reduce the linear expansion coefficient of the molded article. However, a molded article obtained using the olefin-based copolymer obtained by the method of patent document 1 has a problem of a large linear expansion coefficient.

The present invention has been made in view of the above problems, and an object thereof is to provide an olefin copolymer capable of obtaining a molded article having a small linear expansion coefficient, and a film containing the olefin copolymer.

Means for solving the problems

The olefin copolymer according to the present invention includes a monomer unit (1) derived from at least one selected from the group consisting of ethylene and a linear alpha-olefin having 3 to 20 carbon atoms, and a monomer unit (2) derived from a cyclic olefin represented by formula (I), and satisfies requirements (a) to (c).

(a) The glass transition temperature is 220 ℃ or higher.

(b) The ratio (Mw/Mn) of the weight average molecular weight Mw in terms of polystyrene to the number average molecular weight Mn in terms of polystyrene, as measured by gel permeation chromatography, is 2.2 or less.

(c) The refractive index is less than 1.540.

[ chemical formula 1]

(in the formula (I), m represents an integer of 0 or more R ⁷ ～R ¹⁸ Each independently represents a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms. R ¹¹ ～R ¹⁴ When there are plural, they may be the same or different. R ¹⁶ And R ¹⁷ May be bonded to each other and form a ring together with the carbon atom to which they are bonded)

The film according to the present invention contains the above-mentioned olefin copolymer.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, an olefin copolymer capable of giving a molded article having a small linear expansion coefficient and a film comprising the olefin copolymer can be provided.

Detailed Description

Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

< olefin copolymer >

The olefin copolymer according to the present embodiment includes a monomer unit (1), and the monomer unit (1) is derived from at least one selected from the group consisting of ethylene and a linear α -olefin having 3 to 20 carbon atoms. The monomer unit (1) is preferably ethylene.

Examples of the linear α -olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, and 1-decene. Among them, propylene, 1-butene, 1-hexene or 1-octene is preferable, and propylene is more preferable. The linear alpha-olefin having 3 to 20 carbon atoms may be used alone in 1 kind or in combination with 2 or more kinds. The "linear α -olefin" refers to a linear olefin having a carbon-carbon unsaturated double bond at the α -position.

The olefin copolymer according to the present embodiment includes a monomer unit (2) derived from a cyclic olefin represented by the following general formula (I).

[ chemical formula 2]

(in the formula (I), m represents an integer of 0 or more R ⁷ ～R ¹⁸ Each independently represents a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms. R ¹¹ ～R ¹⁴ When a plurality of the compounds exist, they may be the same or different. R ¹⁶ And R ¹⁷ May be bonded to each other and form a ring together with the carbon atom to which they are bonded)

m is an integer of 0 or more, preferably an integer in the range of 0. ltoreq. m.ltoreq.3.

As R ⁷ ～R ¹⁸ Examples of the hydrocarbyl group having 1 to 20 carbon atoms which is one member of the substituents include an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, or a dodecyl group; aryl groups such as phenyl, tolyl, and naphthyl; aralkyl groups such as benzyl and phenethyl; and groups obtained by substituting a part of hydrogen atoms of the alkyl group, the aryl group, and the aralkyl group with a halogen atom. . Among them, an alkyl group, an aryl group or an aralkyl group is preferable. Namely, R ⁷ ～R ¹⁸ Preferably a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or an aralkyl group having 7 to 20 carbon atoms.

Examples of the cyclic olefin represented by the above general formula (I) include norbornene, 5-methylnorbornene, 5-ethylnorbornene, 5-butylnorbornene, 5-phenylnorbornene, 5-benzylnorbornene, tetracyclododecene, tricyclodecene, tricycloundecene, pentacyclopentadecene, pentacyclohexadecene, 8-methyltetracyclododecene, 8-ethyltetracyclododecene and the like. Among them, norbornene is preferable from the viewpoint of easiness of availability of the raw material monomer. The cyclic olefin represented by the above general formula (I) may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The olefin-based copolymer according to the present embodiment preferably has a double-stranded structure including the monomer unit (2). By containing such a double-stranded structure, heat resistance can be improved as compared with a copolymer having the same content of the monomer unit (2). The presence or absence of the double-stranded structure can be determined by ¹³ And C-NMR spectroscopy. For example, in the case of a tetracyclodecene-ethylene copolymer, signals of ethylene-tetracyclodecene-ethylene chains, which are isolated chains derived from tetracyclodecene, appear near 54.7ppm and near 51.1ppm, signals of ethylene-tetracyclodecene-ethylene chains, which are double chains of tetracyclodecene derived from an inside-outside (endo-exo) bond, appear near 51.5ppm and near 50.8ppm, and signals of ethylene-tetracyclodecene-ethylene chains derived from an outside-outside (exo-exo) bond appear near 55.3ppm and near 54.3ppm, and thus the determination can be made based on the pattern of signals near 55ppm and near 50ppm (pattern).

The double-stranded structure of the monomer unit (2) includes a meso-type double-strand represented by the following structural formula (II) and/or a racemic-type double-strand represented by the following structural formula (III).

[ chemical formula 3]

[ chemical formula 4]

The ratio of meso form duplex to racemic form duplex (meso form duplex/racemic form duplex) is preferably 0.50 or less, more preferably 0.01 to 0.20, from the viewpoint of solvent resistance of the copolymer.

The olefin-based copolymer according to the present embodiment is preferably an ethylene-norbornene copolymer including a monomer unit (1) derived from ethylene and a monomer unit (2) derived from norbornene, from the viewpoint of heat resistance and processability.

The olefin-based copolymer according to the present embodiment may further include another monomer unit (3). Examples of the other monomer unit (3) include: conjugated dienes such as butadiene and isoprene; non-conjugated dienes such as 1, 4-pentadiene; acrylic acid; acrylic esters such as methyl acrylate and ethyl acrylate; methacrylic acid; methacrylic acid esters such as methyl methacrylate and ethyl methacrylate; vinyl acetate, and the like.

The olefin copolymer according to the present embodiment has a content of the monomer unit (1) of 1 mol% or more and 30 mol% or less and a content of the monomer unit (2) of 70 mol% or more and 99 mol% or less, based on 100 mol% of the total of the content of the monomer unit (1) and the content of the monomer unit (2), from the viewpoint of heat resistance.

In the olefin copolymer according to the present embodiment, (a) the glass transition temperature (Tg) is 220 ℃ or higher, preferably 240 ℃ or higher and 320 ℃ or lower, from the viewpoint of obtaining a molded article having a small linear expansion coefficient. In this specification, the glass transition temperature (Tg) is a softening temperature measured by thermomechanical analysis (TMA) based on jis k 7196.

The olefin-based copolymer according to the present embodiment has (b) a ratio (Mw/Mn) of a weight average molecular weight Mw in terms of polystyrene to a number average molecular weight Mn in terms of polystyrene, as measured by gel permeation chromatography, of 2.2 or less, preferably 1.6 or more and 2.0 or less, more preferably 1.6 or more and 1.95 or less, further preferably 1.65 or more and 1.95 or less, and particularly preferably 1.65 or more and 1.9 or less, from the viewpoint of obtaining a molded article having a small linear expansion coefficient and improving strength and transparency.

The olefin-based copolymer according to the present embodiment has a weight average molecular weight Mw of preferably more than 300,000, more preferably 350,000 or more, still more preferably 400,000 or more, and particularly preferably 500,000 or more, from the viewpoint of improving strength. From the viewpoint of improving moldability, the weight average molecular weight Mw is preferably 2,000,000 or less, more preferably 1,500,000 or less, further preferably 1,000,000 or less, and particularly preferably 800,000 or less.

The olefin-based copolymer according to the present embodiment has a refractive index (c) of preferably less than 1.540, more preferably 1.520 or more and less than 1.540, from the viewpoint of obtaining a molded article having a small linear expansion coefficient.

From the viewpoint of processability, the solubility of the olefin-based copolymer according to the present embodiment in toluene is preferably 300mg/mL or more.

< method for producing olefin copolymer >

The olefin copolymer according to the present embodiment is produced by: a method for producing a polymer, which comprises polymerizing a monomer unit (1) derived from at least one selected from the group consisting of ethylene and a linear alpha-olefin having 3 to 20 carbon atoms with a monomer unit (2) derived from a cyclic olefin represented by the formula (I) in the presence of a catalyst comprising a transition metal complex (alpha) represented by the general formula (IV) as one component.

[ chemical formula 5]

(in the formula (IV), M represents a transition metal element of group 4 of the periodic Table of the elements Cp represents a group having a cyclopentadienyl skeleton A represents an atom of group 16 of the periodic Table of the elements B represents an atom of group 14 of the periodic Table of the elements X ¹ And X ² The halogen atom, the alkyl group having 1 to 20 carbon atoms, the halogenated alkyl group having 1 to 20 carbon atoms, the alkoxy group having 1 to 20 carbon atoms, the aryloxy group having 6 to 20 carbon atoms or the disubstituted amino group having 2 to 20 carbon atoms, which may be the same or different. R ¹ ～R ⁶ Represents a hydrogen atom, a halogen atom, a carbon atom number of 1 to20 hydrocarbon group, C1-20 halogenated hydrocarbon group, C1-20 alkoxy group, C6-20 aryloxy group, C2-20 disubstituted amino group or C1-20 silyl group, which may be the same or different, and may optionally be bonded to form a ring).

M is a transition metal element of group 4 of the periodic Table of the elements (revised 1989 of IUPAC inorganic chemical nomenclature), and examples thereof include a titanium atom, a zirconium atom, a hafnium atom and the like.

Cp is a group having a cyclopentadienyl skeleton, and examples thereof include a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group, a fluorenyl group, and a substituted fluorenyl group. Specific examples thereof include cyclopentadienyl, methylcyclopentadienyl, tetramethylcyclopentadienyl, n-propylcyclopentadienyl, primary butylcyclopentadienyl, phenylcyclopentadienyl, indenyl, methylindenyl, n-propylindenyl, primary butylindenyl, phenylindenyl, fluorenyl, methylfluorenyl, n-propylfluorenyl, phenylfluorenyl, and dimethylfluorenyl.

Among them, cyclopentadienyl, methylcyclopentadienyl, tetramethylcyclopentadienyl, primary butylcyclopentadienyl, indenyl, methylindenyl or fluorenyl is preferable.

A is an atom of group 16 of the periodic Table of the elements, and examples thereof include an oxygen atom, a sulfur atom and the like. Among them, oxygen atom is preferable.

B is an atom of group 14 of the periodic Table of the elements, and examples thereof include a carbon atom, a silicon atom, a germanium atom and the like. Among them, carbon atom or silicon atom is preferable.

X ¹ 、X ² The halogen atom, the alkyl group with 1 to 20 carbon atoms, the halogenated alkyl group with 1 to 20 carbon atoms, the alkoxy group with 1 to 20 carbon atoms, the aryloxy group with 6 to 20 carbon atoms or the disubstituted amino group with 2 to 20 carbon atoms, which can be the same or different. Among them, a halogen atom is preferable.

As X ¹ 、X ² Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

X ¹ 、X ² When the number of carbon atoms is 1 to 20, the number of carbon atoms is preferably 1 to 10. Specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, octyl, n-hexyl, n-octyl, phenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, naphthyl and benzyl.

As X ¹ 、X ² Specific examples of the halogenated hydrocarbon group include a fluoromethyl group, a difluoromethyl group, a 1-fluoroethyl group, a 1, 1-difluoroethyl group, a 1, 2-difluoroethyl group, a 1,1, 2-trifluoroethyl group, a tetrafluoroethyl group, a chloromethyl group, a dichloromethyl group, a 1-chloroethyl group, a 1, 1-dichloroethyl group, a 1, 2-dichloroethyl group, a 1,1, 2-trichloroethyl group, a 1,1,2, 2-tetrachloroethyl group, a bromomethyl group, a dibromomethyl group, a 1-bromoethyl group, a 1, 1-dibromoethyl group, a 1, 2-dibromoethyl group, a 1,1, 2-tribromoethyl group, a 1,1,2, 2-tetrabromoethyl group, a 2-fluorophenyl group, a 3-fluorophenyl group, a 4-fluorophenyl group, a 2, 3-difluorophenyl group, a 2, 4-difluorophenyl group, a 2, 5-difluorophenyl group, a, 2, 6-difluorophenyl group, 2,3, 4-trifluorophenyl group, 2,3, 5-trifluorophenyl group, 2,3, 6-trifluorophenyl group, 2,3,4, 5-tetrafluorophenyl group, 2,3,4, 6-tetrafluorophenyl group, pentafluorophenyl group, 2-chlorophenyl group, 3-chlorophenyl group, 4-chlorophenyl group, 2, 3-dichlorophenyl group, 2, 4-dichlorophenyl group, 2, 5-dichlorophenyl group, 2, 6-dichlorophenyl group, 2,3, 4-trichlorophenyl group, 2,3, 5-trichlorophenyl group, 2,3, 6-trichlorophenyl group, 2,3,4, 5-tetrachlorophenyl group, 2,3,4, 6-tetrachlorophenyl group, pentachlorophenyl group, 2-bromophenyl group, 3-bromophenyl group, 4-bromophenyl group, 2, 3-dibromophenyl group, 2, 4-dibromophenyl, 2, 5-dibromophenyl, 2, 6-dibromophenyl, 2,3, 4-tribromophenyl, 2,3, 5-tribromophenyl, 2,3, 6-tribromophenyl, 2,3,4, 5-tetrabromphenyl, 2,3,4, 6-tetrabromphenyl, pentabromophenyl, etc.

As X ¹ 、X ² Specific examples of the alkoxy group include methoxy, ethoxy, propoxy, isopropoxy, primary butoxy, secondary butoxy, tertiary butoxy, isobutoxy, n-pentyloxy, neopentyloxy, n-hexyloxy, n-octyloxy and the like.

As X ¹ 、X ² Specific examples of the aryloxy group include a phenoxy group, a 2-methylphenoxy group, a 3-methylphenoxy group, a 4-methylphenoxy group, a naphthyloxy group and the like.

So-called X ¹ 、X ² The disubstituted amino group in the case of a disubstituted amino group means an amino group to which 2 substituents are bonded. Specific examples thereof include dimethylamino group, diethylamino group, di-n-propylamino group, diisopropylamino group, di-n-butylamino group, di-tert-butylamino group, diisobutylamino group, di-n-hexylamino group, di-n-octylamino group, diphenylamino group and the like.

R ¹ ～R ⁶ The compound is a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a halogenated hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a disubstituted amino group having 2 to 20 carbon atoms or a silyl group having 1 to 20 carbon atoms, and may be the same or different, and they may be optionally bonded to form a ring. Of these, R ¹ ～R ⁶ Preferably a hydrocarbon group having 1 to 20 carbon atoms.

As R ¹ ～R ⁶ Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

R ¹ ～R ⁶ When the alkyl group is used, the number of carbon atoms is preferably 1 to 10. Specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, n-octyl, phenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 2, 3-dimethylphenyl, 2, 4-dimethylphenyl, 2, 5-dimethylphenyl, 2, 6-dimethylphenyl, 2,3, 4-trimethylphenyl, 2,3, 5-trimethylphenyl, 2,3, 6-trimethylphenyl, 2,3,4, 5-tetramethylphenyl, 2,3,4, 6-tetramethylphenyl, pentamethylphenyl and the like.

As R ¹ ～R ⁶ Specific examples of the halogenated hydrocarbon group include fluoromethyl group, difluoromethyl group, 1-fluoroethyl group, 1-difluoroethyl group, 1, 2-difluoroethyl group, 1, 2-trifluoroethyl group, tetrafluoroethyl group, chloromethyl group, dichloromethyl group, 1-chloroethyl group, 1-dichloroethyl group, 1, 2-dichloroethyl group, 1, 2-trichloroethyl group, 1,2, 2-tetrachloroethyl group, bromomethyl group, dibromomethyl group, 1-bromoethyl group, 1-dibromoethyl group, 1, 2-dibromoethyl group, 1, 2-tribromoethyl group, 1,2, 2-tetrabromoethyl group, 2-fluorophenyl group, 3-fluorophenyl group4-fluorophenyl group, 2, 3-difluorophenyl group, 2, 4-difluorophenyl group, 2, 5-difluorophenyl group, 2, 6-difluorophenyl group, 2,3, 4-trifluorophenyl group, 2,3, 5-trifluorophenyl group, 2,3, 6-trifluorophenyl group, 2,3,4, 5-tetrafluorophenyl group, 2,3,4, 6-tetrafluorophenyl group, pentafluorophenyl group, 2-chlorophenyl group, 3-chlorophenyl group, 4-chlorophenyl group, 2, 3-dichlorophenyl group, 2, 4-dichlorophenyl group, 2, 5-dichlorophenyl group, 2, 6-dichlorophenyl group, 2,3, 4-trichlorophenyl group, 2,3, 5-trichlorophenyl group, 2,3, 6-trichlorophenyl group, 2,3,4, 5-tetrachlorophenyl group, 2,3,4, 6-tetrachlorophenyl group, Pentachlorophenyl, 2-bromophenyl, 3-bromophenyl, 4-bromophenyl, 2, 3-dibromophenyl, 2, 4-dibromophenyl, 2, 5-dibromophenyl, 2, 6-dibromophenyl, 2,3, 4-tribromophenyl, 2,3, 5-tribromophenyl, 2,3, 6-tribromophenyl, 2,3,4, 5-tetrabromphenyl, 2,3,4, 6-tetrabromphenyl, pentabromophenyl, and the like.

As R ¹ ～R ⁶ Specific examples of the alkoxy group include methoxy, ethoxy, propoxy, isopropoxy, primary butoxy, secondary butoxy, tertiary butoxy, isobutoxy, n-pentyloxy, neopentyloxy, n-hexyloxy, n-octyloxy and the like.

As R ¹ ～R ⁶ Specific examples of the aryloxy group include a phenoxy group, a 2-methylphenoxy group, a 3-methylphenoxy group, a 4-methylphenoxy group, a naphthyloxy group and the like.

So-called R ¹ ～R ⁶ The disubstituted amino group in the case of a disubstituted amino group means an amino group to which 2 substituents are bonded. Specific examples thereof include a dimethylamino group, a diethylamino group, a di-n-propylamino group, a diisopropylamino group, a di-n-butylamino group, a di-sec-butylamino group, a di-tert-butylamino group, a di-isobutylamino group, a di-n-hexylamino group, a di-n-octylamino group, a diphenylamino group and the like.

As R ¹ ～R ⁶ Specific examples of the silyl group include a trimethylsilyl group, a triethylsilyl group, a tri-n-propylsilyl group, a triisopropylsilyl group, a tri-primary butylsilyl group, a tri-sec-butylsilyl group, a tri-tert-butylsilyl group, a triisobutylsilyl group, and a triphenylsilyl group.

Specific examples of the compound represented by the general formula (IV) include isopropylidene (cyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride, isopropylidene (methylcyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride, isopropylidene (dimethylcyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride, isopropylidene (trimethylcyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride, isopropylidene (tetramethylcyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride, isopropylidene (n-propylcyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride, and isopropylidene (n-propylcyclopentadienyl) (3-tert-butyl-5-methyl- 2-phenoxy) titanium dichloride, isopropylidene (primary butylcyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride, isopropylidene (phenylcyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride, isopropylidene (cyclopentadienyl) (3-tert-butyl-2-phenoxy) titanium dichloride, isopropylidene (methylcyclopentadienyl) (3-tert-butyl-2-phenoxy) titanium dichloride, isopropylidene (dimethylcyclopentadienyl) (3-tert-butyl-2-phenoxy) titanium dichloride, isopropylidene (trimethylcyclopentadienyl) (3-tert-butyl-2-phenoxy) titanium dichloride, isopropylidene (tetramethylcyclopentadienyl) (3-tert-butyl-2-phenoxy) bis (phenoxy) titanium dichloride Titanium chloride, isopropylidene (n-propylcyclopentadienyl) (3-tert-butyl-2-phenoxy) titanium dichloride, isopropylidene (primary butylcyclopentadienyl) (3-tert-butyl-2-phenoxy) titanium dichloride, isopropylidene (phenylcyclopentadienyl) (3-tert-butyl-2-phenoxy) titanium dichloride, isopropylidene (cyclopentadienyl) (2-phenoxy) titanium dichloride, isopropylidene (methylcyclopentadienyl) (2-phenoxy) titanium dichloride, isopropylidene (dimethylcyclopentadienyl) (2-phenoxy) titanium dichloride, isopropylidene (trimethylcyclopentadienyl) (2-phenoxy) titanium dichloride, isopropylidene (tetramethylcyclopentadienyl) (2-phenoxy) titanium dichloride, isopropylidene (n-propylcyclopentadienyl) (2-phenoxy) titanium dichloride, isopropylidene (n-butylcyclopentadienyl) (2-phenoxy) titanium dichloride, isopropylidene (2-phenyloxy) titanium dichloride, and the like, Isopropylidene (primary butylcyclopentadienyl) (2-phenoxy) titanium dichloride, isopropylidene (phenylcyclopentadienyl) (2-phenoxy) titanium dichloride, and the like.

In addition, compounds obtained by changing titanium in the above-mentioned specific examples to zirconium or hafnium, and compounds containing them and obtained by changing isopropylidene to dimethylsilylene, diphenylsilylene, or methylene can also be similarly exemplified. Examples of compounds obtained by changing dichloride to dibromide, diiodide, dimethyl, dibenzyl, dimethoxy and diethoxide are also given in the same manner.

The transition metal complex (α) represented by the above general formula (IV) can be used in combination with various cocatalysts as a catalyst for producing the olefin copolymer according to the present embodiment. The co-catalyst is a compound which interacts with the transition metal complex (α) to generate an active species for polymerization of cyclic olefins and alkenyl aromatic hydrocarbons. Examples thereof include an organoaluminum compound (. beta.) and/or any of the following compounds (. gamma.1) to (. gamma.3), but the structure of the polymerization active species produced by using these cocatalysts is not clear.

(gamma 1) formula BQ ¹ Q ² Q ³

(gamma 2) general formula J ⁺ (BQ ¹ Q ² Q ³ Q ⁴ ) ^-

(gamma 3) general formula (L-H) ⁺ (BQ ¹ Q ² Q ³ Q ⁴ ) ^-

As the organoaluminum compound (β), a known organoaluminum compound can be used. Specifically, the compound has the general formula (beta 1) E ¹ _a AlZ _3-a An organoaluminum compound represented by the formula { -Al (E) { (beta 2) { -Al (E) } ² )-O-} _b A cyclic aluminoxane having the structure shown, and a compound having the general formula (. beta.3) E ³ {-Al(E ³ )-O-} _c AlE ³ ₂ Linear aluminoxane of the structure shown (wherein, E ¹ 、E ² 、E ³ Is a C1-8 hydrocarbon group, all E ¹ All of E ² And all of E ³ May be the same or different. Z represents hydrogen or halogen, and all Z may be the same or different. Examples thereof include any one of a represents an integer of 0 to 3, b represents an integer of 2 or more, and c represents an integer of 1 or more), or a mixture of 2 to 3 kinds thereof.

As general formula E ¹ _a AlZ _3a The organoaluminum compound (. beta.1) represented byExamples thereof include trialkylaluminums such as trimethylaluminum, triethylaluminum, tripropylaluminum, triisobutylaluminum, trihexylaluminum and the like; dialkylaluminum chlorides such as dimethylaluminum chloride, diethylaluminum chloride, dipropylaluminum chloride, diisobutylaluminum chloride and dihexylaluminum chloride; alkylaluminum dichlorides such as methylaluminum dichloride, ethylaluminum dichloride, propylaluminum dichloride, isobutylaluminum dichloride and hexylaluminum dichloride; and dialkylaluminum hydrides such as dimethylaluminum hydride, diethylaluminum hydride, dipropylaluminum hydride, diisobutylaluminum hydride and dihexylaluminum hydride. Among them, trialkylaluminum is preferable, and triethylaluminum or triisobutylaluminum is more preferable.

As a compound having the formula { -Al (E) ² )-O-} _b A cyclic aluminoxane (. beta.2) having the structure shown in the general formula E ³ {-Al(E ³ )-O-} _c AlE ³ ₂ E in the Linear aluminoxane (. beta.3) of the structure shown ² 、E ³ Specific examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl and neopentyl. Among them, methyl or isobutyl is preferable. b is an integer of 2 or more, preferably an integer of 2 to 40. c is an integer of 1 or more, preferably an integer of 1 to 40.

The above aluminoxane can be prepared by various methods. The method is not particularly limited, and the method can be prepared by a known method. For example, there may be mentioned a method of producing the metal complex by contacting a solution obtained by dissolving trialkylaluminum (e.g., trimethylaluminum) in an appropriate organic solvent (e.g., benzene, aliphatic hydrocarbon, etc.) with water, and a method of producing the metal complex by contacting trialkylaluminum (e.g., trimethylaluminum) with a metal salt containing crystal water (e.g., copper sulfate hydrate, etc.).

As compound (. gamma.1), the general formula BQ ¹ Q ² Q ³ Boron compound represented by the formula (gamma 2) formula J ⁺ (BQ ¹ Q ² Q ³ Q ⁴ ) ^- Boron compound represented by the formula (gamma 3) or a compound represented by the formula (L-H) ⁺ (BQ ¹ Q ² Q ³ Q ⁴ ) ^- Any one of the boron compounds represented by (1).

General formula BQ ¹ Q ² Q ³ In the boron compound (. gamma.1), B is a boron atom in a valence state of 3, and Q ¹ ～Q ³ Is a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a halogenated hydrocarbon group having 1 to 20 carbon atoms, a substituted silyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms or a di-substituted amino group having 2 to 20 carbon atoms, which may be the same or different. Q ¹ ～Q ³ Preferably a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or a halogenated hydrocarbon group having 1 to 20 carbon atoms.

As a general formula BQ ¹ Q ² Q ³ Specific examples of the boron compound (. gamma.1) include tris (pentafluorophenyl) borane, tris (2,3,5, 6-tetrafluorophenyl) borane, tris (2,3,4, 5-tetrafluorophenyl) borane, tris (3,4, 5-trifluorophenyl) borane, tris (2,3, 4-trifluorophenyl) borane and phenylbis (pentafluorophenyl) borane. Among these, tris (pentafluorophenyl) borane is preferable.

General formula J ⁺ (BQ ¹ Q ² Q ³ Q ⁴ ) ^- In the boron compound (. gamma.2), B is a boron atom in a valence state of 3, and Q ¹ ～Q ⁴ And Q in the above (. gamma.1) ¹ ～Q ³ The same is true. Furthermore, J ⁺ Is an inorganic or organic cation. General formula J ⁺ (BQ ¹ Q ² Q ³ Q ⁴ ) ^- In the boron compound (. gamma.2) represented, J as an inorganic cation ⁺ Examples thereof include ferrocenium cation, alkyl-substituted ferrocenium cation, and silver cation. J as an organic cation ⁺ Examples thereof include triphenylmethyl cation. As (BQ) ¹ Q ² Q ³ Q ⁴ ) ^- Examples thereof include tetrakis (pentafluorophenyl) borate, tetrakis (2,3,5, 6-tetrafluorophenyl) borate, tetrakis (2,3,4, 5-tetrafluorophenyl) borate, tetrakis (3,4, 5-trifluorophenyl) borate, tetrakis (2,2, 4-trifluorophenyl) borate, phenylbis (pentafluorophenyl) borate, tetrakis (3, 5-bistrifluoromethylphenyl) borate and the like.

Specific combinations thereof include ferroceniumtetrakis (pentafluorophenyl) borate, 1' -dimethylferroceniumtetrakis (pentafluorophenyl) borate, silvertetrakis (pentafluorophenyl) borate, triphenylmethyltetrakis (3, 5-bistrifluoromethylphenyl) borate, and the like. Among them, triphenylmethyltetrakis (pentafluorophenyl) borate is preferable.

General formula (L-H) ⁺ (BQ ¹ Q ² Q ³ Q ⁴ ) ^- In the boron compound (. gamma.3), B is boron in the valence state of 3, and Q ¹ ～Q ⁴ With Q in the above boron compound (. gamma.1) ¹ ～Q ³ The same is true. Furthermore, L is a neutral Lewis base, (L-H) ⁺ Is bronsted acid (Bronstedacid).

General formula (L-H) ⁺ (BQ ¹ Q ² Q ³ Q ⁴ ) ^- (L-H) as a Bronsted acid among the boron compounds (. gamma.3) represented by (A) ⁺ Examples thereof include trialkyl-substituted ammonium onium, N-dialkylanilinium, dialkylammonium onium and triarylphosphonium onium. As (BQ) ¹ Q ² Q ³ Q ⁴ ) ^- Examples thereof include the same ions as described above.

Specific combinations thereof include triethylammoniumtetra (pentafluorophenyl) borate, tripropylammoniumtetra (pentafluorophenyl) borate, tri (N-butyl) ammoniumtetra (3, 5-bistrifluoromethylphenyl) borate, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, N-diethylanilinium tetrakis (pentafluorophenyl) borate, N-2,4, 6-pentamethylanilinium tetrakis (pentafluorophenyl) borate, N-dimethylanilinium tetrakis (3, 5-bistrifluoromethylphenyl) borate, diisopropylammoniumtetra (pentafluorophenyl) borate, dicyclohexylammoniumtetra (pentafluorophenyl) borate, triphenylphosphoniumtetra (pentafluorophenyl) borate, tris (methylphenyl) phosphoniumtetra (pentafluorophenyl) borate, triethylammoniumtetra (pentafluorophenyl) borate, tripropylammoniumtetra (pentafluorophenyl) borate, and triethylammoniumtetra (pentafluorophenyl) borate, Tris (dimethylphenyl) phosphonium tetrakis (pentafluorophenyl) borate, and the like. Among them, tri (N-butyl) ammonium tetrakis (pentafluorophenyl) borate or N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate is preferable.

The cocatalyst is preferably used in combination with an organoaluminum compound (. beta.) and a compound (. gamma.).

The transition metal complex (α), the organoaluminum compound (β) and/or the compound (γ) represented by the general formula (IV) may be used by being introduced in any order at the time of polymerization, but a reaction product obtained by contacting a combination of these arbitrary compounds in advance may be used.

The molar ratio of the cocatalyst to the transition metal complex (. alpha.) is preferably 0.01 to 10,000, more preferably 0.5 to 2,000. When the catalyst component is used in a solution state, the concentration of the transition metal complex (α) is preferably 0.0001 mmol/l to 5 mmol/l, more preferably 0.001 mmol/l to 1 mmol/l. The amount of the catalyst component used is preferably 0.00001 mol% or more and 1 mol% or less, more preferably 0.0001 mol% or more and 0.1 mol% or less, based on the total amount of all monomers used.

The polymerization method of the olefin copolymer according to the present embodiment is not particularly limited, and any method such as a batch or continuous gas phase polymerization method, a bulk polymerization method, a solution polymerization method using an appropriate solvent, or a slurry polymerization method may be used.

When a solvent is used, various solvents can be used under such conditions that the catalyst is not deactivated, and examples of such solvents include: hydrocarbons such as benzene, toluene, pentane, hexane, heptane, cyclohexane, and the like; halogenated hydrocarbons such as methylene chloride and ethylene dichloride.

When a solvent is used, the ethylene partial pressure in the polymerization system is 50kPa to 400kPa, preferably 50kPa to 300kPa, and the hydrogen partial pressure is preferably 0kPa to 100 kPa. When ethylene and hydrogen are charged into the system, it is preferable to pressurize the system under a hydrogen partial pressure and then pressurize the system under an ethylene partial pressure. Further, the solution of the cyclic olefin represented by the general formula (I) may be fed into the polymerization reaction tank, and then toluene may be fed.

The polymerization temperature is 50 ℃ or higher, preferably 50 ℃ or higher and 150 ℃ or lower, and more preferably 50 ℃ or higher and 100 ℃ or lower. A chain transfer agent such as hydrogen may be added to adjust the molecular weight of the polymer.

The olefin-based copolymer according to the present embodiment may be used in combination with known additives such as an antioxidant, a weather resistant agent, a lubricant, an antiblocking agent, an antistatic agent, an antifogging agent, an antidrip agent (japanese text: dripper), a pigment, and a filler, if necessary.

The olefin copolymer according to the present embodiment can be molded into various molded articles. As a method for molding into various molded articles, known molding methods such as inflation molding, T-die molding, calendering molding, blow molding, sheet molding, lamination molding, injection molding, foam molding, profile extrusion molding, and the like can be used.

The olefin copolymer according to the present embodiment can provide a molded article having a small linear expansion coefficient. Namely, a molded article having excellent dimensional stability can be provided. Therefore, it can be suitably used for: industrial materials such as automobile parts, electric and electronic parts; optical materials such as lenses, prisms, optical fibers, and recording media; packaging materials such as trays for food packaging and films for food packaging; and so on.

< membrane >

The film according to the present embodiment contains the above-described olefin copolymer.

The film according to the present embodiment may be a single-layer film, or may be a multilayer film including at least 1 layer formed of the film according to the present embodiment. When the film is a single-layer film, it can be produced by, for example, a T-die molding method, an inflation molding method, a calender molding method, or the like. When the film is a multilayer film, it can be produced by a multilayer film forming method such as a coextrusion method, an extrusion lamination method, a thermal lamination method, or a dry lamination method.

The thickness of the film according to the present embodiment is preferably 5 μm to 500 μm, and more preferably 10 μm to 300 μm.

The film according to the present embodiment may be subjected to surface treatment such as corona discharge treatment, flame treatment, plasma treatment, and ozone treatment by a method generally industrially employed.

The olefin-based copolymer and the film containing the olefin-based copolymer according to the present embodiment are not limited to the above-described embodiments, and various modifications may be made without departing from the scope of the present invention. The configurations, methods, and the like of the embodiments other than those described above may be arbitrarily combined, and the configurations, methods, and the like of the 1 embodiment described above may be applied to the configurations, methods, and the like of the other embodiments described above.

Examples

The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

For the synthesis of the ethylene-norbornene copolymer, toluene manufactured by Sumitomo chemical Co., Ltd., 2-norbornene (hereinafter referred to as "NB") manufactured by Mitsukawa chemical industry Co., Ltd., triisobutylaluminum (hereinafter referred to as "TIBA") manufactured by Tosohffinechem Co., Ltd., N-dimethylanilinium tetrakis (pentafluorophenyl) borate (hereinafter referred to as "AB") manufactured by AGC Co., Ltd., etc. were used. .

As toluene, there was used a toluene obtained by dehydrating with a molecular sieve 13X (manufactured by Union Showa Co.) and activated alumina (manufactured by Sumitomo chemical Co., Ltd., NKHD-24) and then removing dissolved oxygen by blowing nitrogen gas.

As NB, one obtained by dissolving NB in toluene, dehydrating it with molecular sieve 13X (manufactured by Union showa and Co., Ltd.) and activated alumina (NKHD-24 manufactured by Sumitomo chemical Co., Ltd.) and then removing dissolved oxygen by blowing nitrogen gas (hereinafter, referred to as "NB solution") was used. The NB concentration in the NB solution was measured by gas chromatography.

Isopropylidene (cyclopentadienyl) (3-tert-butyl-5-methyl-2-phenoxy) titanium dichloride (hereinafter referred to as "complex 1") was synthesized by the method described in Japanese patent application laid-open No. 9-183809.

< example 1 >

Into an autoclave, the inside of which was dried under reduced pressure, 1501mL of NB solution (NB concentration: 3.00M) was added, and the temperature was raised to 60 ℃. While stirring the inside of the system, ethylene partial pressure: after pressurization at 100kPa, 4.0mL (concentration: 1.0M) of a hexane solution of TIBA, 0.16g of AB, and 10.0mL (concentration: 10mM) of a toluene solution of complex 1 were added to initiate polymerization of ethylene and NB. During the polymerization, the temperature in the system was maintained at 60 ℃ and ethylene was continuously supplied to maintain the pressure in the system at the initial value. After 3 hours from the start of the polymerization, 5.0mL of water was added to stop the polymerization, and the solution in the autoclave was withdrawn. To the extracted solution were added 1500g of toluene and 100g of magnesium sulfate, followed by stirring, and then 100mL of water was added thereto, followed by stirring, and the solid was removed by filtration. The obtained liquid was added dropwise to acetone, and the precipitated powder was separated by filtration. The separated powder was further washed with acetone and dried at 120 ℃ for 2 hours under reduced pressure, whereby 210.0g of the ethylene-norbornene copolymer of example 1 was obtained. The synthesis conditions are shown in table 1.

< examples 2 to 6 and comparative example 1 >

An ethylene-norbornene copolymer was obtained in the same manner as in example 1, except that the synthesis conditions were changed as shown in table 1. In the case of introducing hydrogen, pressurization under a hydrogen partial pressure is performed before pressurization under an ethylene partial pressure. In addition, when toluene is charged, the NB solution is charged and then toluene is charged.

[ Table 1]

The physical properties and compositions of the ethylene-norbornene copolymers of the examples and comparative examples were determined by the following methods. The results are shown in Table 3.

< glass transition temperature >

The glass transition temperature (Tg) of the ethylene-norbornene copolymer was measured by thermomechanical analysis (TMA) based on jis k 7196. Specifically, the sheet-like test piece (thickness: 1.0mm) molded by the vacuum press was measured under the following conditions, and the starting point (onset) of the displacement when the indenter fell into the test piece was defined as the softening temperature.

The device comprises the following steps: TMA/SS6200 manufactured by Hitachi high-TechScience

Indenter (probe) diameter: 1mm

Load: 780mN

Temperature program: raising the temperature from 20 ℃ to 380 ℃ at a speed of 5 ℃/min

< Mw and Mn >

The weight average molecular weight Mw of the ethylene-norbornene copolymer in terms of polystyrene and the number average molecular weight Mn in terms of polystyrene were measured by gel permeation chromatography (hereinafter referred to as "GPC"). GPC measurement was carried out under the following conditions, and a chromatographic base line was defined and a peak was designated based on the description of ISO 16014-1.

(GPC apparatus and software)

The device comprises the following steps: HLC-8121GPC/HT (manufactured by Tosoh corporation)

Measurement software: GPC-8020model II data Collection Version4.32 (manufactured by Tosoh corporation)

Analysis software: GPC-8020modelII data analysis Version4.32 (manufactured by Tosoh corporation)

(measurement conditions)

GPC column: TSKgelGMH 6-HT7.8mmI.D.. times.300 mm (manufactured by Tosoh corporation) 3 roots

Mobile phase: BHT was added at 0.1w/V to ortho-dichlorobenzene (and light, extra grade) and used

Flow rate: 1 mL/min

Temperature of the column oven: 140 deg.C

Auto-sampler temperature: 140 deg.C

Temperature of the system oven: 40 deg.C

And (3) detection: differential Refractive Index Detector (RID)

RID cell temperature: 140 deg.C

Injection amount of sample solution: 300 μ L

Calibration standard for GPC column: the standard polystyrene manufactured by Tosoh corporation was measured in accordance with the combinations shown in Table 2 below, and 5mL of o-dichlorobenzene (same composition as the mobile phase) was added to each combination and dissolved for 2 hours at room temperature.

[ Table 2]

Combination 1	F700 0.4mg	F20 0.9mg	A5000 1.2mg
				Combination 2	F288 0.4mg	F10 1.0mg	A2500 1.2mg
Combination 3	F80 0.7mg	F4 1.1mg	A1000 1.3mg
				Combination 4	F40 0.8mg	F2 1,1mg	A500 1.3mg

(conditions for preparing sample solution)

Solvent: BHT was added at 0.1w/v in ortho-dichlorobenzene (and light, special grade) using sample solution concentrations: 1mg/mL

Automatic vibrator for dissolution: DF-8020 (made by Tosoh corporation)

Dissolution conditions: a sample of 5mg was sealed in a 1000 mesh SUS metal mesh bag, the metal mesh bag in which the sample was sealed was put in a test tube, 5mL of o-dichlorobenzene (same composition as the mobile phase) was added to the test tube, the test tube was covered with aluminum foil, the test tube was set on DF-8020, and the mixture was stirred at 140 ℃ for 120 minutes at a stirring speed of 60 cycles/minute.

< refractive index >

The refractive index of the ethylene-norbornene copolymer was determined by the following method: using a sheet-like sample formed to a thickness of 100 μm by a vacuum press, the obtained sample was measured under the following conditions.

Equipment: abbe refractometer TYPE-3 manufactured by Atago

Wavelength of light source: 589.3nm

Intermediate liquid: 1-bromonaphthalene

Measuring temperature: 23 + -1 deg.C

< meso type double-chain/racemic type double-chain >

The NB content of the ethylene-norbornene copolymer and the ratio of meso form double strand to racemic form double strand of NB double strand (meso form double strand/racemic form double strand) were used ¹³ C-NMR measurement. ¹³ The C-NMR measurement conditions were as follows.

The device comprises the following steps: AVANCE600, 10mm cryoprobe manufactured by Bruker

Measuring temperature: 135 deg.C

The determination method comprises the following steps: proton decoupling method

Concentration: 100mg/ml

Cumulative number of times: 1024 times

Pulse width: 45 degree

Pulse repetition time: 4 seconds

Chemical shift value benchmark: tetramethylsilane

Solvent: with 1, 2-dichlorobenzene-d ₄ With 1,1,2, 2-tetrachloroethane-d ₂ 85 of (1): 15 (volume ratio)

The NB content of the ethylene-norbornene copolymer was calculated based on the assignment described in "r.a.wendt, g.fink, macromol.chem.phys., 2001,202,3490" based on 1, 2-dichlorobenzene (127.68 ppm). In more detail, the NB content may be used according to the use ¹³ Signal integral values observed in chemical shift values of 44.0 to 52.0ppm of the spectrum measured by C-NMR: i is _C2，C3 (derived from carbon atoms at positions 2 and 3 of the norbornene ring)) The integral value of the signal observed in the chemical shift value of 27.0-33.0 ppm: I.C. A _C5，C6 +I _CE (carbon atoms at positions 5 and 6 of the norbornene ring and carbon atom at the ethylene part) was determined by the following formula.

NB content (mol%) ═ I _C2，C3 /(I _C5，C6 +I _CE )×100

The meso-type double strand/racemic-type double strand in the ethylene-norbornene copolymer was calculated based on the assignments described in "R.A. Wendt, G.Fink, Macromol.chem.Phys., 2001,202,3490" and "Japanese patent application laid-open No. 2008-285656" based on 1,1,2, 2-tetrachloroethane (74.24 ppm). More specifically, meso form double strand/racemic form double strand may be used according to the use ¹³ Signal integral values observed in chemical shift values 27.5 to 28.4ppm of the spectrum measured by C-NMR: i is _C5，C6 An integrated value of signals observed at m (carbon atoms at positions 5 and 6 of the norbornene ring derived from the meso-type double strand), a chemical shift value of 28.4 to 29.6 ppm: i is _C5，C6 R (carbon atoms at positions 5 and 6 of the norbornene ring derived from the racemic double strand) was determined by the following formula.

Meso form duplex/racemic form duplex ═ I _C5，C6 -m/I _C5，C6 -r

Solubility of < toluene >

The solubility of the ethylene-norbornene copolymer in toluene was measured by the following method. First, 1000mg of an ethylene-norbornene copolymer and 3mL of a solvent were added to a sample bottle, and then the mixture was stirred at room temperature for 2 hours. Then, the solid phase and the liquid phase were separated by filtration, the solid phase was dried at 80 ℃ for 2 hours under reduced pressure, and the weight X (mg) after drying was measured. Then, the solubility was calculated according to the following formula: y (mg/mL). When a solid phase was not visually observed after stirring at room temperature for 2 hours, the solubility was more than 333 mg/mL.

Y＝(1000-X)/3

< coefficient of linear expansion >

The linear expansion coefficient of the ethylene-norbornene copolymer was determined by thermomechanical analysis (TMA) based on JISK 7197. Specifically, the linear expansion coefficient was calculated under the following conditions by measurement at 50 ℃ to 100 ℃.

Indenter (probe) diameter: 3.5mm

Loading: 38.5mN

Temperature program: raising the temperature from 20 ℃ to 130 ℃ at a speed of 5 ℃/min

Test piece: cuboid of 10mm x 1mm

[ Table 3]

From the results shown in Table 3, it is understood that the ethylene-norbornene copolymers of examples 1 to 6 satisfying all the requirements of the present invention can provide molded articles having a smaller linear expansion coefficient than the ethylene-norbornene copolymer of comparative example 1.

Claims

1. An olefin-based copolymer comprising:

a monomer unit (1) derived from at least one selected from the group consisting of ethylene and a linear alpha-olefin having 3 to 20 carbon atoms; and

a monomer unit (2) derived from a cyclic olefin represented by the formula (I),

the olefin copolymer satisfies the requirements (a) to (c),

(a) the glass transition temperature is above 220 ℃;

(b) a ratio (Mw/Mn) of a weight average molecular weight Mw in terms of polystyrene to a number average molecular weight Mn in terms of polystyrene, as measured by gel permeation chromatography, of 2.2 or less;

(c) the refractive index is less than 1.540,

[ chemical formula 1]

In the formula (I), m represents an integer of 0 or more;

R ⁷ ～R ¹⁸ each independently represents a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms; at R ¹¹ ～R ¹⁴ When a plurality of them exist, they may be the same or different; r ¹⁶ And R ¹⁷ May be bonded to each other and form a ring together with the carbon atom to which they are bonded.

2. The olefin-based copolymer according to claim 1, wherein the polystyrene-equivalent weight average molecular weight Mw is greater than 300,000.

3. The olefin-based copolymer according to claim 1 or 2, which satisfies the requirement (a'),

(a') a glass transition temperature of 240 ℃ to 320 ℃.

4. The olefin-based copolymer according to any one of claims 1 to 3, which satisfies the requirement (b'),

(b') the ratio (Mw/Mn) of the weight average molecular weight Mw in terms of polystyrene to the number average molecular weight Mn in terms of polystyrene, as measured by gel permeation chromatography, is 1.6 to 2.0.

5. The olefin-based copolymer according to any one of claims 1 to 4, which satisfies the requirement (c'),

(c') a refractive index of 1.520 or more and less than 1.540.

6. The olefin copolymer according to any one of claims 1 to 5, wherein the amount of the olefin copolymer is such that, with respect to 100 mol% in total of the amount of the monomer unit (1) and the amount of the monomer unit (2),

the content of the monomer unit (1) is 1 mol% or more and 30 mol% or less, and

the content of the monomer unit (2) is 70 mol% or more and 99 mol% or less.

7. The olefin copolymer according to any one of claims 1 to 6, wherein the cyclic olefin represented by formula (I) is norbornene.

8. The olefin-based copolymer according to claim 7, which is an ethylene-norbornene copolymer.

9. The olefin copolymer according to any one of claims 1 to 8, which comprises a double-stranded structure of the monomer unit (2), wherein the ratio of meso double-strand to racemic double-strand (meso double-strand/racemic double-strand) is 0.50 or less.

10. The olefin copolymer according to claim 9, wherein the ratio of meso form duplex to racemic form duplex (meso form duplex/racemic form duplex) is from 0.01 to 0.20.

11. The olefin-based copolymer according to any one of claims 1 to 10, having a solubility in toluene of 300mg/mL or more.

12. A film comprising the olefin copolymer according to any one of claims 1 to 11.