JP5822225B2 - Hydrocarbon copolymer, process for producing the same, and molded article - Google Patents

Description

The present invention relates to a hydrocarbon copolymer, a method for producing the same, and a molded body. More specifically, the present invention relates to a hydrocarbon-based copolymer which is colorless and transparent and has a number average molecular weight in the range of 5 × 10 ^{4 to} 5 × 10 ⁶ obtained by copolymerizing a norbornene derivative and an N-substituted maleimide. And a method for producing the same, and a molded body made of such a hydrocarbon copolymer.

  Hydrocarbon polymers obtained by polymerizing norbornene derivatives have high transparency and heat resistance, and are expected to be used for various molded articles (especially for optical films).

  Of these, the production of hydrocarbon copolymers by copolymerizing norbornene with other monomers having an electron-attracting substituent, such as maleic anhydride or N-substituted maleimide, has also been studied. (Refer nonpatent literature 1). However, the hydrocarbon copolymer has a number average molecular weight of less than 10,000 and has low moldability.

Shenyang Huagong Xueyuan Xuebao, 15 (3), 161-165 (2001).

  Accordingly, an object of the present invention is to provide a hydrocarbon copolymer excellent in transparency, heat resistance and moldability, a method for producing the same, and a molded body comprising such a hydrocarbon copolymer.

  As a result of intensive studies, the present inventors have determined that a hydrocarbon copolymer obtained by copolymerizing a norbornene derivative having a specific structure and an N-substituted maleimide having a specific structure so that the number average molecular weight falls within a specific range. I found.

That is, the present invention includes the following.
[1] The number average molecular weight obtained by copolymerizing the norbornene derivative represented by the general formula (1) and the N-substituted maleimide represented by the general formula (2) is in the range of 5 × 10 ^{4 to} 5 × 10 ⁶ . A hydrocarbon-based copolymer.

（式（１）中、Ｒ¹〜Ｒ¹²は、それぞれ独立して水素原子または炭化水素基を示す。Ｒ⁹またはＲ¹⁰とＲ¹¹またはＲ¹²とは互いに環を形成していてもよい。ｎは０または１である。）

(In Formula (1), R < ¹ > -R < ¹² > shows a hydrogen atom or a hydrocarbon group each independently. R < ⁹ > or R < ¹⁰ > and R < ¹¹ > or R < ¹² > may mutually form the ring. n is 0 or 1.)

（式（２）中、Ｒ¹³はフッ素不含の炭素数１〜１２のアルキル基、１つ以上のアルキル基を有してもよい炭素数３〜８の環状アルキル基、またはアルキル基、アリール基およびアラルキル基から選ばれる１つ以上の置換基を有してもよい炭素数６〜１４のアリール基を示す。）

(In the formula (2), R ¹³ is a fluorine-free alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms which may have one or more alkyl groups, or an alkyl group, aryl. And an aryl group having 6 to 14 carbon atoms which may have one or more substituents selected from a group and an aralkyl group .)

[2] The hydrocarbon copolymer according to the above [1], which has a glass transition temperature in the range of 250 to 400 ° C.
[3] A molded article comprising the hydrocarbon copolymer of [1] or [2].
[4] A Lewis acid or Bronsted selected from a fluorine-containing alcohol, a fluorine-containing diol, and a halogenated hydrocarbon, comprising a norbornene derivative represented by the general formula (1) and an N-substituted maleimide represented by the general formula (2) The method for producing a hydrocarbon copolymer according to the above [1] or [2], comprising radical copolymerization in the presence of an acid.

  The hydrocarbon copolymer of the present invention is excellent in transparency, heat resistance and moldability. The hydrocarbon-based copolymer according to the present invention can provide a molded body having an arbitrary shape such as a film, a sheet, a plate, or a container by a known molding method. Such a molded article of the present invention is useful, for example, as a substrate for laminating a transparent conductive thin film. Specifically, it can be used for touch panels, solar cells, flat panel displays (liquid crystal displays, electroluminescence) and the like.

1 is a diagram showing a ¹ H-NMR spectrum of a hydrocarbon-based copolymer obtained in Example 1. FIG. 1 is a diagram showing a DSC curve of a hydrocarbon-based copolymer obtained in Example 1. FIG.

The hydrocarbon-based copolymer of the present invention is obtained by copolymerizing a norbornene derivative having a specific structure and an N-substituted maleimide having a specific structure.
The norbornene derivative used in the present invention is a compound represented by the formula (1). R < ¹ > -R < ¹² > in Formula (1) shows a hydrogen atom or a hydrocarbon group each independently. Such a hydrocarbon group is preferably a saturated hydrocarbon group having 1 to 8 carbon atoms. Examples of the saturated hydrocarbon group having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, An n-hexyl group etc. are mentioned. R ^{1 to} R ¹² may each be one kind or plural kinds.

R ⁹ or R ¹⁰ and R ¹¹ or R ^{12 in} formula (1) may be connected to each other to form a ring.
Specific examples of the norbornene derivative in which R ⁹ or R ¹⁰ and R ¹¹ or R ¹² form a ring include dicyclopentadiene (tricyclo [5.2.1.0 ^2,6 ] deca-4,8 -Dienes) and tricyclo [4.3.1 ^2,5 . 0] Dec-3-ene.

Specific examples of norbornene derivatives used in the present invention include 2-norbornene, 5-methylnorbornene, 5,6-dimethylnorbornene, 1-methylnorbornene, 7-methylnorbornene, 5,5,6-trimethylnorbornene, 5- Phenylnorbornene, 5-benzylnorbornene, 5-ethylidenenorbornene, 5-vinylnorbornene, dicyclopentadiene, tricyclo [4.3.1 ^2,5 . 0] dec-3-ene, tricyclo [4.4.1 ^2,5 . 0] unda-3-ene, tetracyclododecene, 8-ethyltetracyclododecene, 8-ethylidenetetracyclododecene, and the like. Of these, 2-norbornene is preferred.

The N-substituted maleimide used in the present invention is a compound represented by the formula (2). R ¹³ is fluorine-free with and alkyl groups having 1 to 12 carbon atoms in the formula (2), fluorine-free with and cyclic alkyl group having 3 to 20 carbon atoms or a fluorine-free with and having 6 to 20 carbon atoms, An aryl group is shown.
Examples of the alkyl group containing no fluorine and having 1 to 12 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n- A pentyl group, n-hexyl group, etc. are mentioned.

The cyclic alkyl group containing no fluorine and having 3 to 20 carbon atoms is preferably a cyclic alkyl group having 3 to 8 carbon atoms which is free of fluorine and may have one or more substituents. Examples of the cyclic alkyl group having 3 to 8 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the substituent which the C3-C8 cyclic alkyl group may have include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert. Examples thereof include alkyl groups such as -butyl group, n-pentyl group, and n-hexyl group.

As the aryl group having no fluorine and having 6 to 20 carbon atoms, an aryl group having 6 to 14 carbon atoms which is free of fluorine and may have one or more substituents is preferable. Examples of the aryl group having 6 to 14 carbon atoms include a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. Examples of the substituent that the aryl group having 6 to 14 carbon atoms may have include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. Examples thereof include alkyl groups such as butyl group, n-pentyl group and n-hexyl group; aryl groups such as phenyl group; and aralkyl groups such as benzyl group.
R ¹³ may be one type or a plurality of types.

  Specific examples of the N-substituted maleimide used in the present invention include N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-isobutylmaleimide, Nt- N-alkylmaleimides such as butylmaleimide; N-cycloalkylmaleimides, such as N-cyclohexylmaleimide, N-cyclopentylmaleimide, N-norbornylmaleimide, N-cyclohexylmethylmaleimide, N-cyclopentylmethylmaleimide; N-phenylmaleimide; N-chlorophenylmaleimide, N-methylphenylmaleimide, N-naphthylmaleimide, N-hydroxyphenylmaleimide, N-methoxyphenylmaleimide, N-carboxyphenylmaleimide, N-nitro E cycloalkenyl maleimide, etc. N- aryl maleimides such as N- tribromophenyl maleimide. Among these, N-cycloalkylmaleimide and N-alkylmaleimide are preferable from the viewpoint of weather resistance, N-cycloalkylmaleimide is more preferable, and N-cyclohexylmaleimide is particularly preferable from the viewpoint of heat resistance.

The hydrocarbon copolymer of the present invention has a number average molecular weight in the range of 5 × 10 ^{4 to} 5 × 10 ⁶ , and is 1 × 10 ⁵ to 1 × 10 ⁶ from the viewpoints of moldability and ease of production. A range is preferable. The number average molecular weight is a conversion value measured based on a calibration curve prepared with standard polystyrene using size exclusion chromatography.

  The weight average molecular weight of the hydrocarbon copolymer of the present invention can be measured simultaneously with the measurement of the number average molecular weight. The molecular weight distribution (weight average molecular weight / number average molecular weight) is preferably in the range of 1.0 to 3.0, and more preferably in the range of 1.2 to 2.5.

  The hydrocarbon copolymer of the present invention may be a random copolymer, an alternating copolymer, a graft copolymer, a block copolymer, etc., but the homogeneity of the resulting hydrocarbon copolymer, From the viewpoint of ease of production and the like, a random copolymer and an alternating copolymer are preferable.

  The glass transition temperature of the hydrocarbon copolymer of the present invention is preferably in the range of 250 to 400 ° C, more preferably in the range of 300 to 370 ° C. Further, the 5% weight loss temperature measured by TG-DTA is preferably 300 ° C. or higher, and more preferably 350 ° C. or higher.

In the production of the hydrocarbon-based copolymer of the present invention, the N-substituted maleimide to be used for copolymerization is preferably used in a range of 0.1 to 10 mol times that of the norbornene derivative, and is preferably 0.25 to 1.5 mol times. It is more preferable to use in the range. You may copolymerize another monomer in the range which does not impair the effect of this invention. The amount of such other monomer used is preferably 5% by mass or less of the total amount of the norbornene derivative and the N-substituted maleimide.
Other monomers that can be used in the production of the hydrocarbon copolymer of the present invention include cyclopentene, 3-methylcyclopentene, 4-methylcyclopentene, 3,4-dimethylcyclopentene, 3,5-dimethylcyclopentene, and 3-chloro. Cyclopentene, cyclohexene, 3-methylcyclohexene, 4-methylcyclohexene, 3,4-dimethylcyclohexene, 3-chlorocyclohexene, cycloheptene, 1,3-cyclopentadiene, 1,3-cyclohexadiene, 1, Alicyclic unsaturated hydrocarbons such as 4-cyclohexadiene, 5-ethyl-1,3-cyclohexadiene, 1,3-cycloheptadiene, 1,3-cyclooctadiene; α- such as ethylene and propylene Olefins; Aromatic vinyl compounds such as styrene; , Acrylic acid, methacrylic acid, methyl acrylate, ethylene carboxylic acid compound or a derivative thereof such as methyl methacrylate and the like.

  In the production of the hydrocarbon-based copolymer of the present invention, the polymerization reaction between the norbornene derivative and the N-substituted maleimide is preferably radical polymerization from the viewpoint of easy industrial production. The polymerization temperature in radical polymerization is preferably in the range of 0 to 150 ° C, more preferably in the range of 40 to 80 ° C. The polymerization time is preferably in the range of 3 to 300 hours, and more preferably in the range of 6 to 96 hours from the viewpoint of easy control of the polymerization temperature and production efficiency.

  Examples of the initiator used for the radical polymerization include azo compounds such as 2,2′-azobisisobutylnitrile and 2,2′-azobis (2,4-dimethylvaleronitrile); benzoyl peroxide, lauroyl peroxide, dialkyl Milperoxide, dibutyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, diisopropylbenzene hydroperoxide, t-hexylperoxy-2-ethylhexanate, t-butylperoxyisobutyrate, t-perper Examples thereof include peroxides such as oxypivalate.

The radical polymerization may be carried out by any polymerization method such as a bulk polymerization method, a solution polymerization method, a suspension polymerization method and an emulsion polymerization method, but a solution polymerization method is preferred. As a solvent used in such a solution polymerization method, a solvent in which a monomer to be used for copolymerization and the obtained hydrocarbon copolymer is dissolved is preferable.
The solvent may function as a Lewis acid or a Bronsted acid. Solvents that function as Lewis acids or Bronsted acids include 2,2,2-trifluoroethanol, 2,2,3,3,3-pentafluoro-1-propanol, 2,2,3,3,4, 4-hexafluoro-1-butanol, 2,2,3,3,4,4,4-heptafluoro-1-butanol, 2,2,3,3,4,4,5,5-octafluoro-1 -Fluorinated alcohols such as pentanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol 2,2,3,3,4,4-hexafluoro-1,5-pentanediol, 2,2,3,3,4,4,5,5,5-octafluoro-1,6-hexanediol, etc. And the like. Further, halogenated hydrocarbons such as dichloroethane and chloroform may be used as a solvent. These solvents may be used alone or in combination of two or more. In addition, Lewis acid or Bronsted acid may be added to the solvent as an additive.

  In the solution polymerization method, the mass of the entire monomer used for copolymerization is preferably in the range of 5 to 75% by mass, more preferably in the range of 10 to 60% by mass, and more preferably in the range of 20 to 50% by mass. A range is further preferred.

  After performing the solution polymerization, the hydrocarbon copolymer can be recovered from the polymerization reaction solution by a known method. For example, the polymerization reaction solution may be dropped into a poor solvent such as methanol or hexane to precipitate the copolymer, or the polymerization reaction solution may be filtered or washed, and then the solvent may be distilled off.

  The molded product of the present invention is composed of the aforementioned hydrocarbon copolymer. The method for obtaining the molded body is not particularly limited, and examples thereof include an extrusion molding method, an injection molding method, an inflation molding method, a press molding method, and a cast molding method. The shape of the molded body can be arbitrarily selected according to the application. For example, a film, a sheet, a plate, a container, etc. are mentioned.

  Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited to these examples.

(Measurement of reaction rate)
0.05 mL of the reaction solution before the start of the reaction was dissolved in 0.45 mL of deuterated chloroform solution, and ¹ H-NMR measurement was performed. The peak derived from the vinyl proton of norbornene (6.0 to 6.1 ppm) and the vinyl of maleimide The integrated value of the peak derived from proton (6.7 to 6.9 ppm) and the peak derived from phenyl proton of 1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol (7 The ratio (r _n0 , r _m0 ) with the integrated value of .1 to 7.5 ppm was calculated. Next, the reaction solution after the reaction was similarly subjected to ¹ H-NMR measurement, and the integrated values of the peak derived from the vinyl proton of norbornene and the peak derived from the vinyl proton of maleimide and 1,1,1,3,3,3 _-The ratio (r _n1 , r _m1 ) with the integrated value of the peak derived from the phenyl proton of hexafluoro-2-phenyl-2-propanol was calculated, respectively, and relative to the ratio (r _n0 , r _m0 ) before the start of the reaction The reduction rate ((r _n0 -r _n1 ) / r _n0 , (r _m0 -r _m1 ) / r _m0 ) was expressed as a percentage and used as the reaction rate.

(Measurement of molecular weight)
A sample was obtained by dissolving 1 mg of the hydrocarbon-based copolymer obtained in each Example and Comparative Example in 1 mL of tetrahydrofuran. A high performance liquid chromatograph (“HPLC LC” manufactured by JASCO Corporation) in which two samples of this series were connected in series with a polystyrene gel column Shodex K-805L (inner diameter: 8.0 mm, length: 30 cm) manufactured by Showa Denko KK -2000 Plus ") was allowed to flow in as an eluent at a flow rate of 1.0 mL / min, and converted to standard polystyrene using a differential refractometer (RI-2031 manufactured by JASCO Corporation) as a detector at a measurement temperature of 40 ° C. The weight average molecular weight and number average molecular weight were calculated.

(Measurement of glass transition temperature)
The hydrocarbon-based copolymer obtained in each Example and Comparative Example was set in a differential scanning calorimetry (DSC) apparatus (Q200 manufactured by TA Instruments Inc.) and up to 320 ° C. at 10 ° C./min. Increase the temperature, hold for 10 minutes, decrease the temperature to −50 ° C. at 10 ° C./min, hold at −50 ° C. for 5 minutes, increase the temperature to 320 ° C. at 10 ° C./min, hold for 5 minutes, then 40 ° C. The temperature was lowered at 10 ° C./min. The calorie change during that time was measured. The intermediate temperature in the transition behavior at the second temperature rise was defined as the glass transition temperature.

(Measurement of thermal decomposition start temperature)
The hydrocarbon-based copolymer obtained in each example and comparative example was set in a thermal differential measurement (TG-DTA) apparatus (Q500 manufactured by TA Instruments Inc.), and the temperature was increased from 40 ° C to 500 ° C. The temperature was raised at ° C / min. The temperature at which the weight of the set polymer was reduced by 5% was defined as the thermal decomposition start temperature.

Example 1
In a well-dried flask with a glass cock, 1.41 g (15 mmol) of 2-norbornene (manufactured by Tokyo Chemical Industry), 1.34 g (7.5 mmol) of N-cyclohexylmaleimide (manufactured by Tokyo Chemical Industry), as a polymerization initiator. Azobisisobutyronitrile (AIBN: Wako Pure Chemical Industries, Ltd.) 16 mg and dehydrated 1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol (Tokyo Kasei Co., Ltd.) under a nitrogen stream To make a total volume of 5 mL. This mixture was stirred and dissolved uniformly.

  The mixture was heated to 40 ° C. with stirring and stirred for 100 hours for addition polymerization reaction. The reaction rates of 2-norbornene and N-cyclohexylmaleimide were 46% and 90%, respectively. The reaction solution was dropped into 50 ml of methanol to precipitate a solid content. Drying was performed at 25 ° C. under reduced pressure conditions of 10 Pa or less for 24 hours to obtain the saturated hydrocarbon copolymer of the present invention. A unimodal peak was observed in the size exclusion chromatogram of the obtained hydrocarbon copolymer. The hydrocarbon-based copolymer had a number average molecular weight (hereinafter abbreviated as Mn) of 172,000 and a molecular weight distribution (weight average molecular weight / number average molecular weight: hereinafter abbreviated as Mw / Mn) of 1.6. It was.

The ratio of 2-norbornene units and N-cyclohexylmaleimide units in the hydrocarbon-based copolymer obtained above was measured by ¹ H-NMR in deuterated chloroform at 55 ° C. ^{A 1} H-NMR chart is shown in FIG. As shown in FIG. 1, a methine proton (f) adjacent to a nitrogen on a cyclohexyl group derived from an N-cyclohexylmaleimide unit, a methine proton (a and c) derived from a 2-norbornene unit, a methylene proton (b and d ), Methine proton (e) adjacent to the carbonyl group derived from the N-cyclohexylmaleimide unit, and methylene protons (g, h and i) derived from the N-cyclohexylmaleimide unit were observed. From the ratio of the area of f (3.7 to 3.9 ppm) and the sum of the areas of a to e and g to (1.0 to 3.0 ppm), the 2-norbornene unit and the N-cyclohexylmaleimide unit The ratio was found to be 1: 1. In addition, the hydrocarbon copolymer had a thermal decomposition starting temperature of 402 ° C. and a glass transition temperature of 307 ° C.

  The hydrocarbon copolymer was dissolved in tetrahydrofuran to obtain a solution having a concentration of 5% by mass. This was applied onto an aluminum foil and dried at 25 ° C. for 3 hours. This was further dried under reduced pressure at 70 ° C. for 5 hours, and then brought to normal pressure and peeled off from the aluminum foil to obtain a film. The resulting film was 30 μm thick and colorless and transparent.

Example 2
The total amount of dehydrated 1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol was changed to 15 mL, and the amount of methanol added dropwise to the reaction solution was 150 mL. A hydrocarbon copolymer was obtained in the same manner as in Example 1 except that.
The reaction rates of 2-norbornene and N-cyclohexylmaleimide were 32% and 65%, respectively. A monomodal peak was observed in the size exclusion chromatogram of the obtained hydrocarbon copolymer, and Mn was 82,600 and Mw / Mn was 2.3. Moreover, from the measurement by ¹ H-NMR, it was found that the ratio of 2-norbornene units to N-cyclohexylmaleimide units was 1: 1. In addition, the hydrocarbon copolymer had a thermal decomposition starting temperature of 402 ° C. and a glass transition temperature of 306 ° C.
The hydrocarbon copolymer was dissolved in tetrahydrofuran to obtain a solution having a concentration of 5% by mass. This was applied onto an aluminum foil and dried at 25 ° C. for 3 hours. This was further dried under reduced pressure at 70 ° C. for 5 hours, and then brought to normal pressure and peeled off from the aluminum foil to obtain a film. The resulting film was 30 μm thick and colorless and transparent.

Comparative Example 1
The hydrocarbon system was the same as in Example 1 except that toluene (manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of dehydrated 1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol. A copolymer was obtained.
The reaction rates of 2-norbornene and N-cyclohexylmaleimide were 20% and 81%, respectively. A monomodal peak was observed in the size exclusion chromatogram of the obtained hydrocarbon copolymer, and Mn was 4,600 and Mw / Mn was 2.2. Further, the saturated hydrocarbon copolymer was dissolved in tetrahydrofuran to obtain a solution having a concentration of 5% by mass. This was thinly coated on an aluminum foil and dried at room temperature for 3 hours. This was dried under reduced pressure at 70 ° C. for 5 hours, but when it was peeled off from the aluminum foil, it was broken into pieces and the film could not be isolated.

Example 3
A colorless and transparent hydrocarbon-based copolymer was obtained in the same manner as in Example 1 except that 1.29 g (7.5 mmol) of N-phenylmaleimide (manufactured by Tokyo Chemical Industry Co., Ltd.) was used instead of N-cyclohexylmaleimide.
The reaction rates of 2-norbornene and N-phenylmaleimide were 43% and 90%, respectively. A monomodal peak was observed in the size exclusion chromatogram of the obtained hydrocarbon copolymer, and Mn was 172,000 and Mw / Mn was 1.6. Further, from the measurement by ¹ H-NMR, it was found that the ratio of 2-norbornene units to N-methylmaleimide units was 1: 1. The hydrocarbon copolymer had a thermal decomposition starting temperature of 404 ° C. and a glass transition temperature of 284 ° C.

Example 4
A colorless and transparent hydrocarbon-based copolymer was obtained in the same manner as in Example 1, except that 0.83 g (7.5 mmol) of N-methylmaleimide (manufactured by Tokyo Chemical Industry Co., Ltd.) was used instead of N-cyclohexylmaleimide.
The reaction rates of 2-norbornene and N-methylmaleimide were 45% and 88%, respectively. A monomodal peak was observed in the size exclusion chromatogram of the obtained hydrocarbon copolymer, and Mn was 159,000 and Mw / Mn was 2.3. Further, from the measurement by ¹ H-NMR, it was found that the ratio of 2-norbornene units to N-methylmaleimide units was 1: 1. The hydrocarbon copolymer had a thermal decomposition starting temperature of 392 ° C. and a glass transition temperature of 253 ° C.

Example 5
A colorless and transparent hydrocarbon copolymer was obtained in the same manner as in Example 1 except that 0.94 g (7.5 mmol) of N-ethylmaleimide (manufactured by Tokyo Chemical Industry Co., Ltd.) was used instead of N-cyclohexylmaleimide. It was.
The reaction rates of 2-norbornene and N-ethylmaleimide were 44% and 87%, respectively. A monomodal peak was observed in the size exclusion chromatogram of the obtained hydrocarbon copolymer, and Mn was 161,000 and Mw / Mn was 2.4. Moreover, from the measurement by ¹ H-NMR, it was found that the ratio of 2-norbornene units to N-ethylmaleimide units was 1: 1. The hydrocarbon copolymer had a thermal decomposition starting temperature of 395 ° C. and a glass transition temperature of 284 ° C.

  From these results, it can be seen that the hydrocarbon copolymer according to the present invention is excellent in transparency, heat resistance and moldability.

Claims (4)

Hydrocarbon having a number average molecular weight in the range of 5 × 10 ^{4 to} 5 × 10 ⁶ obtained by copolymerizing a norbornene derivative represented by the general formula (1) and an N-substituted maleimide represented by the general formula (2) Copolymer.

(In formula (1), R ^{1 to} R ¹² each independently represent a hydrogen atom or a hydrocarbon group. R ⁹ or R ¹⁰ and R ¹¹ or R ¹² may be linked to each other to form a ring. Good, n is 0 or 1)

(In the formula (2), R ¹³ represents an alkyl group having 1 to 12 carbon atoms of fluorine-free, one or more cyclic alkyl group which has good carbon atoms 3 to be 8 have an alkyl group or an alkyl group, (It represents an aryl group having 6 to 14 carbon atoms which may have one or more substituents selected from an aryl group and an aralkyl group .)   The hydrocarbon copolymer according to claim 1, wherein the glass transition temperature is in the range of 250 to 400 ° C.   The molded object which consists of a hydrocarbon type copolymer of Claim 1 or 2. Presence of Lewis acid or Bronsted acid selected from fluorine-containing alcohols, fluorine-containing diols and halogenated hydrocarbons from norbornene derivatives represented by general formula (1) and N-substituted maleimides represented by general formula (2) The method for producing a hydrocarbon-based copolymer according to claim 1 or 2, comprising radical copolymerization below.

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