JPH03255107A - Production of random cycloolefin copolymer - Google Patents

Abstract

PURPOSE:To produce the title copolymer having a decreased content of foreign matter and improved transparency by drying pellets obtained by pelletizing a specified random cycloolefin copolymer and separating a fine powder from the dried pellets. CONSTITUTION:Ethylene is copolymerized with a cycloolefin of formula I (wherein (n) is 0 or 1; (m) is 0 or a positive integer; R<1> to R<18> are each H, halogen or a hydrocarbon group; R<15> to R<18> may be combined to form a monocyclic or polycyclic ring which may have a double bond, and R<15> and R<16> or R<17> and R<18> may be combined to form an alkylidene group) or formula II (wherein (l) is 0 or an integer of 1 or greater; (m) and (n) are each 0-2; R<1> to R<15> are each H, halogen, an aliphatic or aromatic hydrocarbon group or alkoxy, R<5> or R<6> and R<9> or R<7> may be combined directly or through a 1-3C alkylene group) in the presence of a catalyst comprising a soluble V compound and an organoaluminum compound in a hydrocarbon solvent to obtain a random cycloolefin copolymer. Pellets obtained by pelletizing this copolymer are dried and passed through a classifier to separate a fine powder from the pellets.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a method for producing cyclic olefin random copolymer pellets. More specifically, the present invention is directed to a cyclic olefin random copolymer that can reduce the content of foreign substances contained as impurities and produce cyclic olefin random copolymer pellets that have excellent transparency. The present invention relates to a method for producing combined pellets.

Technical background of the invention A cyclic olefin-based random copolymer consisting of ethylene and a specific bulky cyclic olefin is a synthetic resin with well-balanced optical properties, mechanical properties, thermal properties, etc., and is used for example in optical memory. It is used in the field of optical materials such as disks and optical fibers.

However, in order to manufacture optical memory disks from such cyclic olefin random copolymers, copolymer pellets are usually used, but when optical memory disks are manufactured from these copolymer pellets, very little However, a read error may occur. The present inventors conducted intensive studies to reduce the read errors of optical memory disks manufactured from cyclic olefin random copolymer pellets, and found that -m
found that this was caused by foreign substances contained as impurities in the cyclic olefin random copolymer pellets.

Therefore, there is a strong desire for a method for producing cyclic olefin random copolymer pellets that can reduce the content of foreign substances contained as impurities.

By the way, such cyclic olefin-based random copolymer pellets are conventionally produced by mixing ethylene and a cyclic olefin with a hydrocarbon such as hexane, heptane, or the above-mentioned cyclic olefin in the presence of a catalyst formed from a soluble vanadium compound and an organoaluminum compound. It is produced by copolymerizing the cyclic olefin random copolymer using the following as a solvent, granulating the resulting cyclic olefin random copolymer, and then drying the resulting cyclic olefin random copolymer. The present inventors have conducted intensive studies on a method for producing cyclic olefin random copolymer pellets that have a reduced content of foreign substances contained as impurities and have excellent transparency. The present inventors have discovered that during production, it is sufficient to perform an operation to remove fine particles generated during the granulation process of the cyclic olefin random copolymer and/or the drying process of the pellets, thereby completing the present invention.

Purpose of the Invention The present invention has been made in view of the prior art as described above, and provides a cyclic olefin random copolymer which can reduce the content of foreign substances contained as impurities and has excellent transparency. It is an object of the present invention to provide a method for producing cyclic olefin random copolymer pellets that can produce coalesced pellets.

Summary of the Invention The method for producing cyclic olefin random copolymer pellets according to the present invention comprises (a) ethylene, (b) the following formula [I or [■] (where n is O or 1, m is O or a positive integer, R1-R18 are each independently a hydrogen atom, a halogen atom, or a hydrocarbon group, and R15-R18 are bonded to each other to form a monocyclic or polycyclic ring; The monocyclic or polycyclic ring may have a double bond, and R and R or R17 and R18 may form an alkylidene group).

[In the formula, l is an integer of 0 or 1 or more, m and n
is 0.1 or 2, R1 to R15 are each independently a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or an alkoxy group, and R5 (or R6) and R9 (or ') may be bonded via an alkylene group having 1 to 3 carbon atoms, or may be bonded directly without any group. ] At least one cyclic olefin selected from the group consisting of unsaturated monomers represented by A cyclic olefin-based random copolymer is copolymerized in a liquid phase consisting of a cyclic olefin, and this cyclic olefin-based random copolymer is granulated, and the resulting pellets are dried to form a cyclic olefin-based random copolymer. When producing polymer pellets, granulation process of cyclic olefin random copolymer and/or
Alternatively, the method is characterized in that it includes an operation for separating and removing fine powder generated during the pellet drying process.

According to the present invention, cyclic olefin random copolymer pellets are produced by copolymerizing ethylene and cyclic olefin, granulating the obtained cyclic olefin random copolymer, and then drying the obtained pellets. At this time, the granulation process of the cyclic olefin random copolymer and/or
Alternatively, since the fine powder generated during the pellet drying process is separated and removed, the content of foreign substances contained as impurities is reduced, and cyclic olefin random copolymer pellets with excellent transparency are produced. be able to.

DETAILED DESCRIPTION OF THE INVENTION The method for producing cyclic olefin random copolymer pellets according to the present invention will be specifically described below.

In the present invention, the general formula [I] or the general formula [
Cyclic olefins represented by [2]] and ethylene are co-coated in a hydrocarbon mixed solvent or in a liquid phase consisting of the above-mentioned cyclic olefin in the presence of a catalyst consisting of a vanadium compound and an organoaluminum compound soluble in the solvent. Polymerization to produce a cyclic olefin random copolymer, granulation of the obtained cyclic olefin random copolymer, and drying of the resulting pellets to produce cyclic olefin random copolymer pellets. , granulation process of cyclic olefin random copolymer and/or
Alternatively, an operation is performed to separate and remove fine powder generated during the pellet drying process.

The cyclic olefin represented by the above formula [r] used in the present invention is specifically 1-bicyclo[2,2,1]hept-2-ene-derived tetracyclo[4,4,0,12,S, 17.1.]-]
3-dodecene-derived xacyclo[5,6,l, p, s, 11m, +s
, □z, 'r, 0*th 3-4-heptadensene induced imitation octacyclo [8, 8, 0, 12, *, 1', 7.
1st eye 11,111!6Q1.・QII+? ]-5-tococene derivative, pentacyclo[6,6,1,13-6,
O2・7,0...14]-4-hexadecene derivative Heptacyclo-5-icosene derivative Heptacyclo-5-heneicosene derivative Tricyclo[
4,3,0,12・@]-3-decene derivative, tricyclo[4,3,0,12・I]-3-undecene derivative Pentacyclo[6,5,1,if@, 02・? ,Q@
, +1] -4-pentadecene induced imitation pentacyclopentadecadiene induced image pentacyclo[4,7,0,12,S,0cy13,1.
-3-pentadecene derivative, pentacyclo[7,8,0,p6,02.7.11・I
7, QI I, +81+z, +5) -4-
Eicosene induced image and nonasif t: + [9, 10, 1, 1, 4, 7, 03s
,021@,OI”211+t,2@,QIa,+s,
l+s,+s]-5-bentacocene derivatives.

Specific examples of such compounds are shown below.

hmm 5.10-dimethyltetra CH.

Bicyclo[2,2,1]hept-2-ene derivatives such as; 2,7.9-)limethylteCH.

9-Inbutyl-2,7- 9,11,12-)dimethyl 8-methyltetrasic 8-ethyltetrashif 嘗・] 3-Dodecene 8-hexyltetracy 01・H, Ding ,1・]-]3-dodese -ethyl-11,12-dime 9-isobutyl-11,12 5,8,9,10-tetramethy ·eye] Dodesen 8-methyl-9-ethylte 8-chlorotetrashif -3-dodecene -3-dodecene B]-3-dodecene ,1.]-3-dodecene s, 1, +1]-3-dodecene hmm 8-ethylidene-9-iso 1・]-]3-dodese One dodecene -3-dodecene 12, I, lte・I@]-3-dodese hmm +1]-]3-dodese 111〒、I・〒〒〕-〕3-Dodese t, s4-t, 1-]-]3-dode Se8-n-propylidene9 hmm One dodecene 8-n-propylidene-9 8-isopropylidene [4,4,0,12・s,1v III Cor 3 One dodecene One dodecene 1・]-]3-dodese N1・]-3 Dodesen 8-n-propylidene-9 [4,4,0,12 5,17・1]-3 CH.

[4,4,0,12 SJT, 11]-3 Tetracyclo[4,4,0,12・s,p・ro]-3-dodecene derivatives such as 1-dodecene and 1-dodecene; (blank below) 8-isopropylide ndodecene, heavy 4]-4-hebutadecene Iff, Q2. T, Qil, +4-hexacyclo[6,6,1,116,11 such as 4-heptadecene Q2, 7, (p decene, l=] -4-hebutadecene derivative; +8. Octacyclo[8,8,0,12,*,1'
7.1 ■ 1@, 1 ) , + 6 , Q3, -Ql 21] -5-tococene derivative: @ , Ql 2・+ ? ]-] 5-heneicosene, which hebutacyclo-5-icosene derivative or hebutacyclo-5-heneicosene derivative;
+ 4-4-hexadecene derivatives; tricyclo[4,3,0,1t.! such as 5-methyl-tricyclo1,3-dimethyl-penta! ]-3-decene derivatives; pentacyclo[6,5 such as tricyclo[4,4,0,1''·s]-3-undecene derivatives such as 1,6-dimethylbenta10-methyl-tricif-14,15-dimethylben ,1,1”・6
．． O2? , Q9, +! Pentacyclo[4,7,0,12, B, 0@13. 19 12] = 3-pentadecene derivative; 2@, 0th, 1., II@ 1@] = nonacyclo[9,10,1,1', ? , Q8. I, Q21@, Ql
t, 21.11 11, Q14 -1+s mouth] -5-bentacocene-derived cocene bodies can be mentioned.

(Left below) 2, cho, 11., 1ma, 0th 1@11 18] Hebutacyclo [7,8,0,1' @, OR, 1,'j11@, +1. such as -4-eicosene. Q +1.1eJ12.1J -4-eicosene derivative: Also, as a cyclic olefin represented by the above formula [nl] used in the present invention, 14 Specifically, 1! Examples include the following compounds.

15-phenyl-bicyclo[ -2-en ] can be mentioned.

(The following is a blank space) The cyclic olefin represented by the above formula [I] or [nl] can be easily produced by subjecting a cyclopentadiene and a corresponding olefin to a Diels-Alder reaction.

In the present invention, a catalyst formed from a soluble vanadium compound and an organoaluminum compound is used when copolymerizing ethylene and cyclic olefins.

Specifically, the vanadium compound has the general formula vO (
OR), Xb or V (OR), X.

(However, R is a hydrocarbon group, 0≦a≦3.0≦b≦3.
2≦a+b≦3, O≦C≦4, O≦d≦4.3≦c10d
A vanadium compound represented by ≦4) or an electron donor adduct thereof is used.

More specifically, VOCl3, ■0(OC2H5)C12, VO (OC2H5) 2 CI.

VO(0-n-C3H7)C12, VO(0-n-C4H9)C12, VO(OCH), VOBr-VCA'
<, 2 5 3 2 V OCl , V O (0-n-C4H9) 3.
A vanadium compound such as 2 vct .20C8HI70H is used.

Electron donors that may be used when preparing the soluble vanadium catalyst component include alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic or inorganic acids, ethers, acid amides, and acid anhydrides. Oxygen-containing electron donors such as silanes, alkoxysilanes, and nitrogen-containing electron donors such as ammonia, amines, nitriles, and isocyanates can be mentioned. More specifically, the number of carbon atoms in methanol, ethanol, propatool, pentanol, hexanol, octatool, dodecanol, octadecyl alcohol, oleyl alcohol, benzyl alcohol, phenylethyl alcohol, cumyl alcohol, isopropyl alcohol, isopropylbenzyl alcohol, etc. Alcohols having 1 to 18 carbon atoms, which may have a lower alkyl group such as phenol, cresol, xylenol, ethylphenol, propylphenol, nonylphenol, cumylphenol, naphthol, etc.
20 phenols: acetone, methyl ethyl ketone,
Ketones having 3 to 15 carbon atoms such as methyl isobutyl ketone, acetophenone, benzophenone, and benzoquinone;
Aldehydes with 2 to 15 carbon atoms such as acetaldehyde, propionaldehyde, octylaldehyde, benzaldehyde, tolualdehyde, naphthaldehyde, methyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, ethyl propionate , methyl butyrate, ethyl valerate, methyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, ethyl dichloroacetate, methyl methacrylate, ethyl crotonate, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, propyl benzoate, benzoate butyl acid, octyl benzoate, cyclohexyl benzoate, phenyl benzoate, benzyl benzoate, methyl toluate, ethyl toluate, amyl toluate, ethyl ethylbenzoate, methyl anisate, n-butyl maleate, diisobutyl methylmalonate , cyclohexenecarboxylic acid di-n
-Hexyl, diethyl nadic acid, diisopropyl tetrahydrophthalate, diethyl phthalate, diisobutyl phthalate, di-n-butyl phthalate, di-2-ethylhexyl phthalate, γ-butyrolactone, δ-valerolactone, coumarin, phthalide, ethylene carbonate, etc. carbon number 2~
30 organic acid esters; acid halides having 2 to 15 carbon atoms such as acetyl chloride, benzoyl chloride, toluyl chloride, anisyl chloride; methyl ether;
Ethers with 2 to 20 carbon atoms such as ethyl ether, isopropyl ether, butyl ether, amyl ether, tetrahydrofuran, anisole, and diphenyl ether; acid amides such as acetic acid amide, benzoic acid amide, and toluic acid amide; methylamine, ethylamine, diethylamine, Amines such as tributylamine, piperidine, tribenzylamine, aniline, pyridine, picoline, tetramethylenediamine; Nitriles such as acetonitrile, benzonitrile, tolnitrile; Alkoxysilanes such as ethyl silicate, diphenyldimethoxysilane, etc. I can do it. Two or more types of these electron donors can be used.

As the organoaluminum compound, a compound having at least one AJ-carbon bond in the molecule is used, for example, (where R1 and R2 are the number of carbon atoms, usually 1 to 15, preferably 1 to 4). The hydrocarbon groups contained may be the same or different. X is halogen, m is O≦m≦3
, n is a number of 0≦n<3, p is a number of 0≦n<3, q is a number of 0≦q<3, and m+n+p+q=3), 1 (i) General formula Examples include complex alkylated products of Group 1 metals and aluminum represented by MAA'R (where Ml is Li, Na, or Ni, and R1 is the same as above).

Examples of the organoaluminum compounds belonging to (i) above include the following.

General formula R', AI (OR2) -m (where R and R2 are the same as above. m is preferably 1
．． 5≦m<3).

General formula R' 1IAI X3° (where R1 is the same as above, X is halogen, and m is preferably O<m<3).

General formula R' mAt R31 (Here, R1 is the same as above. m is preferably 2≦m<3
).

(Here, R and R2 are the same as above. X is halogen, O
<m≦3.0≦n<3.0≦q<3, m + n +
q = 3).

More specifically, aluminum compounds belonging to (i) include trialkylaluminiums such as triethylaluminum and tributylaluminium, trialkenylaluminums such as triisopropenylaluminum, dialkylaluminums such as diethylaluminum ethoxide, dibutylaluminum butoxide, etc. In addition to alkyl aluminum sesquialkoxides such as alkoxide, ethyl aluminum sesquiethoxide and butyl aluminum sesqui butoxide, partially alkoxylated alkoxides having an average composition strength of 2.50.5 expressed as R' AI (OR) etc. aluminum alkyl,
dialkylaluminum halides such as diethylaluminum chloride, dibutylaluminum chloride, diethylaluminium bromide, alkylaluminum sesquihalides such as ethylaluminum sesquichloride, butylaluminum sesquichloride, ethylaluminum sesquipromide, ethylaluminum dichloride, propylaluminum dichloride, Partially halogenated alkylaluminiums such as alkylaluminum cybarides such as butylaluminum dibromide, dialkylaluminum hydrides such as diethylaluminum hydride, dibutylaluminum hydride, ethylaluminum dicdride, probylaluminum dihydride, etc. Examples include partially hydrogenated aluminum alkyls such as alkylaluminium haladride, partially alkoxylated and halogenated alkyl aluminums such as ethylaluminum ethoxy chloride, butylaluminum butoxychloride, ethylaluminum ethoxybromide. It may also be a compound similar to (i), such as an organoaluminum compound in which two or more aluminum atoms are bonded via an oxygen atom or a nitrogen atom. Specifically, such compounds include (C2H5)2AlOAl (C2H5)2, (C4H
5) 2AlOAl (C4H9)2, CaHs can be exemplified.

As a compound belonging to the above (i), L i /akJ
(c H>, L I A1 (C7R15) 4, etc.). Among these, it is particularly preferable to use alkylaluminum halides, alkylaluminium cybarides, or mixtures thereof.

In the present invention, a hydrocarbon solvent can also be used when copolymerizing ethylene and the above-mentioned cyclic olefin. Such hydrocarbon solvents include pentane,
Aliphatic hydrocarbons and their halogen derivatives such as hexane, heptane, octane, decane, dodecane, and kerosene; Alicyclic hydrocarbons and their halogen derivatives such as cyclohexane, methylcyclopentane, and methylcyclohexane; Aromatics such as benzene, toluene, and xylene Group hydrocarbons and halogen derivatives such as chlorobenzene are used.

In the present invention, ethylene and the cyclic olefin (general formula [
I] or [II]) may be copolymerized, but if necessary, an α-olefin having 3 or more carbon atoms may be copolymerized, and such α-olefins having 3 or more carbon atoms include, for example, Propylene, 1-butene, 4-methyl
-α-olefins having 3 to 20 carbon atoms such as 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. can be mentioned.

Further, other copolymerizable unsaturated monomer components can be copolymerized as necessary within a range that does not impair the purpose of the present invention. Specifically, such copolymerizable unsaturated monomers include cyclopentene, cyclohexene, 3-methylcyclohexene, cyclooctene, etc. in an amount less than equimolar to the cyclic olefin component unit in the random copolymer to be produced. Cycloolefin, 1,4-hexadiene, 4-
Methyl 14-hexadiene, 5-methyl-1,4-hexadiene, 17-octadiene, dicyclopentadiene, 5-ethylidene-2-norbornene, 5-vinyl-2
- Non-conjugated dienes such as norbornene can be exemplified.

When producing a cyclic olefin-based random copolymer, ethylene and the above-mentioned pentacyclopentadecenes (general formula (I)) or aromatic-containing cyclic olefins (
The copolymerization reaction with the general formula [■]) is carried out in a continuous manner.

At this time, the ratio of the organic aluminum compound concentration (C) supplied into the polymerization tank and the organic aluminum compound concentration (C) in the polymerization tank (C/IAA'
OAA'C) is 50 or less, preferably 40-1, more preferably IAA'C is 30-1, and the vanadium compound concentration (Co, ) supplied into the polymerization tank and the vanadium compound concentration (C) in the polymerization tank are , , ), the ratio (Co, /C1,) is 10
The following range is preferably 8 to 1, more preferably 6 to 1.

The soluble vanadium compound and the organoaluminum compound are usually diluted with the hydrocarbon solvent, pentacyclopentadecenes, or aromatic-containing cyclic olefins, respectively, and then supplied to the polymerization tank.

In the present invention, the ratio of aluminum atoms to vanadium atoms (AA'/V) in the polymerization reaction system is 2 or more, preferably 2 to 50. It is particularly desirable that the number is in the range of 3 to 20.

Further, when producing a cyclic olefin random copolymer, the concentration of the soluble vanadium compound in the copolymerization reaction system is usually 0.01 to 5 gram atoms/I, preferably 0.05 to 3 gram atoms/I as vanadium atoms. It is in the range of gram atom/1.

Such a copolymerization reaction of ethylene and cyclic olefins is carried out at a temperature of -50 to 100°C, preferably 30 to 80°C, more preferably -20 to 60°C.

The reaction time for carrying out the above copolymerization reaction (
In the case of a continuous polymerization reaction, the average residence time of the polymerization reaction mixture varies depending on the type of polymerization raw material, the concentration of the catalyst component, and the temperature, but is usually 5 minutes to 5 hours, preferably 1 hour.
It ranges from 0 minutes to 3 hours. Further, the pressure when carrying out the copolymerization reaction is usually 50 kg/cj exceeding O, preferably 20 kg/alf exceeding O. Further, during copolymerization, a molecular weight regulator such as hydrogen may be added to adjust the molecular weight of the resulting copolymer.

When producing a cyclic olefin random copolymer, the molar ratio of ethylene/cyclic olefin is 85/15 to
15/85, more preferably 40/60 to 85/15
It is desirable that it be within the range of .

When the copolymerization reaction of ethylene and cyclic olefins is carried out as described above, a solution of a cyclic olefin random copolymer is obtained. The concentration of the cyclic olefin random copolymer contained in such a copolymer solution is usually
5-300g//.

Preferably it is in the range of 10 to 200 g/J.

In the present invention, ethylene and cyclic olefin are copolymerized as described above, the cyclic olefin random copolymer is granulated, and the resulting pellets are dried to produce cyclic olefin random copolymer pellets. In doing so, the granulation process of the cyclic olefin random copolymer and/or
Alternatively, an operation is performed to separate and remove fine powder generated during the pellet drying process.

To remove fine powder from cyclic olefin random copolymer pellets, for example, a method using a classifier, a method of dispersing the pellets in a fluid such as gas or liquid, and removing fine powder can be adopted. . Specifically, zigzag wind classifier, Iiya style wind centrifugal classifier,
Used are vantongeren type classifiers, cyclones, batch type gravity settling tank type classifiers such as Spitzkasten, GIC type wind classifiers, centrifugal sedimentation machines such as decanters, and the like.

There is also a method of placing a wire mesh on the intake side of the blower and blowing away particles smaller than the opening of the wire mesh using wind power, leaving the pellets on the wire mesh and separating the fine powder, and dispersing the pellets in a liquid such as a flotation machine. A method for removing fine powder by blowing gas into it and attaching it to the floating bubbles. A method for charging static electricity through friction, collision, etc., and removing fine powder based on the difference in the amount of charge, electric charge, and weight. Fluoroacetone, tetrachloride. It is also possible to adopt a method of washing and removing fine powder adhering to the pellet using carbon, water, water containing a surfactant, alcohol, or the like.

If the fine powder generated in the cyclic olefin random copolymer granulation process and/or pellet drying process is separated and removed in this way, reading errors may occur in optical memory disks manufactured from the resulting cyclic olefin random copolymer pellets. can significantly reduce the occurrence of

Although the reason for this is not clear, it is thought to be as follows.

In other words, fine powder is generated in the granulation process of the cyclic olefin random copolymer and/or the pellet drying process, but for some reason, gel-like substances and metal fine powder are contained in this fine powder and are more edible than the pellets. It is included in
If an optical memory disk or the like is manufactured from a cyclic olefin random copolymer pellet obtained without separating and removing this fine powder, it is thought that this fine powder becomes a foreign substance in the disk, and thus a reading error occurs.

Here, in this specification, fine powder means 1 of the weight of pellet particles.
15 or less, preferably 1/10 or less, more preferably 1/10 or less
It means a fine powder having a weight of less than 20. The cyclic olefin random copolymer pellets produced in the present invention usually have a weight of about 0.01 to 0.03 g.

The cyclic olefin random copolymer obtained in the present invention is preferably an amorphous copolymer that does not have a DSC melting point and is also determined by X-ray diffraction.

Furthermore, the ethylene/cyclic olefin molar ratio of the cyclic olefin random copolymer according to the present invention is usually 951.
The range is from 5 to 30/70, preferably from 90/10 to 40/60, and more preferably from 85/15 to 40/60. Further, the glass transition point (Tg) of the cyclic olefin random copolymer is usually 10 to 240°C, preferably 20 to 240°C.
The temperature range is 200°C.

Effects of the Invention In the present invention, when producing cyclic olefin random copolymer pellets as described above, fine powder generated in the granulation process of the cyclic olefin random copolymer and/or the pellet drying process is separated. Since the removal operation is performed, the content of foreign substances contained in the obtained cyclic olefin random copolymer is reduced, and the transparency of the molded article obtained from the copolymer is improved. therefore,
In the optical memory disk manufactured from the cyclic olefin random copolymer pellets according to the present invention, reading errors caused by the disk substrate are significantly reduced.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 [Catalyst preparation 0 (OC2H5) C12 was diluted with cyclohexane,
A vanadium catalyst was prepared with a vanadium concentration of 18.6 mmol/l cyclohexane. On the other hand, ethylaluminum sesquichloride (AI(C2H5) +, s
t, sCI) was diluted with cyclohexane to give an aluminum concentration of 164 mmol/l.
- An organoaluminum catalyst, which is cyclohexane, was prepared.

[Polymerization reactor with baffle plate and stirrer with inner diameter of 70C1 m, total volume of 5701 m, reaction volume of 3001 m, and vertical multi-tube cooler with heat transfer area of 19.4 flf] Then, extract the polymerization solution from the bottom of the polymerization vessel with a stirrer,
Using a polymerization apparatus system equipped with a circulation line that circulates the polymerization solution through the multi-tube cooler and returns it to the polymerization vessel, and a circulation pump installed in the circulation line, ethylene and -
A copolymerization reaction was continuously carried out so as to contain about 1.2 mol% of a physical olefin represented by (3-dodecene) (hereinafter sometimes simply referred to as tetracyclododecene) and butene-1. When carrying out this reaction, the vanadium catalyst (■catalyst) prepared by the above method is
The amount of catalyst was supplied into the polymerization vessel so that the concentration of catalyst was 0.35 mmol/1. Furthermore, this (1) catalyst is diluted in advance using cyclohexane, a polymerization solvent, so that the V catalyst concentration immediately before being supplied to the polymerization vessel is 1.8 times the dilution ratio of the catalyst concentration in the polymerization vessel. and supplied it.

On the other hand, ethylaluminum sesquichloride as an organoaluminum compound was fed into the polymerization vessel in an amount such that Al/■=8.0. In addition, the solution was diluted in advance using cyclohexane, a polymerization solvent, so that the concentration immediately before being supplied to the polymerization vessel was a dilution ratio of 11 relative to the concentration inside the polymerization vessel. The point where these catalysts and organic aluminum catalysts are supplied is near the tip of the upper blade of a stirrer equipped with two stages of six vertical disk turbine blades with a diameter of 0.25 m, where the stirring is strongest, and the dispersion mixing is performed. This was done promptly.

The amount of cyclohexane used as a polymerization solvent was 233 kg/
h into the polymerization vessel. 2.69 kg of ethylene
/h, and hydrogen gas as a molecular weight regulator was added at 2.2NI/h.
was supplied to the gas phase inside the polymerization vessel. The polymerization solution was strongly stirred using a stirrer with a power of 4.4 kw/kL.

The temperature was controlled so that the polymerization temperature was 10° C. by circulating 25% by weight methanol water as a refrigerant through the jacket attached to the outside of the polymerization vessel and the shell side of the multi-tubular cooler.

Nitrogen gas was introduced into the polymerization vessel to control the pressure so that the polymerization pressure was 1.0 kg/adG.

The following method was used to clean the inner wall of the polymerization vessel. In other words, the receiver with a hole partially drilled in the gas phase part of the shaft that connects the agitator and the agitating blade is a dish (spray disk).
was installed. Then, cyclohexane solvent was supplied in an amount of 30 kg/h, tetracyclododecene was supplied in an amount of 14.2 kg/h, and butene-1 was supplied in an amount of 0.41 kg/h into this spray disk. The shaft was rotated, and cyclohexane, tetracyclododecene, and butene-1 were scattered from the holes in the spray disk by the centrifugal force generated by the rotation of the shaft, and sprayed onto the inner wall of the polymerization vessel. The sprayed tetracyclododecene, cyclohexane, and butene-1 passed along the inner wall and mixed into the liquid phase.

When the copolymerization reaction of ethylene, tetracyclododecene, and butene-1 was carried out continuously under the above-mentioned conditions, the concentration of the ethylene-tetracyclododecene-butene-1 copolymer was 4.0 to 4.0. A 3% by weight cyclohexane solution was obtained.

[To the copolymer solution of ethylene and tetracyclododecene extracted from the deashing copolymerizer, boiler water at 80°C and a NaOH solution with a concentration of 4% by weight as a pH adjuster were added,
The copolymerization reaction was stopped and the catalyst residue remaining in the copolymer solution was removed (deashed) from the copolymer solution.

The copolymerization solution after deashing was heated to a temperature of 900 m, with an inner diameter of 900 m,
It was stored in a container with an effective volume of 1.0 - equipped with a stirrer, and cooled to about 30 to 40° C. by flowing water at room temperature through a jacket attached to the outside of the container.

[Filtration] The copolymer solution thus obtained was filtered at 261 kg/
In the amount of h, the outer diameter is 63.5 m +, the inner diameter is 28 m, and the length is 1
The sample was supplied to a filter containing 34 cotton thread-wound filters (vertical wind filters manufactured by Nippon Gensen Co., Ltd.) with a nominal diameter of 1 μm, and was continuously filtered.

Next, a nominally 2 μm S with an outer diameter of 25 mm and a length of 750 m.
The mixture was fed at a rate of 261 kg/h to a filter containing 15 tube-type filters made of laminated metal mesh made of US 304 (vertical type Fujiplate ■ filters made by Fuji Filter Co., Ltd.), and filtered continuously.

Furthermore, the outer diameter is 61mm and the length is 510m, which is a nominal 0.3μm.
SO3304 metal non-woven fabric pleated filter (
Using two filters containing three Brunswick PSPO3 filters, connected in series, the capacity is 261 kg/h.
continuous filtration.

[Precipitation] Acetone was added to the thus filtered copolymer solution to precipitate the copolymer, and the obtained copolymer was separated.

After extracting unreacted monomers from the obtained cyclic olefin random copolymer, the copolymer is separated and dried,
Pelletized and dried.

[Classification] Before filling the pellets and soto dried as described above into the product container, one part of the pellets is separated using an air classifier.
/10 or less in weight, specifically, pellet abrasion powder generated during pellet drying, small-sized pellets, crushed pellet fragments, fine foreign matter adhering to pellets, etc. were removed.

The classifier uses a 370m long zigzag wind classifier.
Fine particles were removed by dropping nitrogen gas from the bottom at 30 to 4 ONm"/h" and dropping the pellets from the top at 300 kg/h.

When optical discs were manufactured from the obtained cyclic olefin random copolymer, reading errors were significantly reduced compared to when optical discs were manufactured from pellets that were not subjected to classification.

Claims (1)

[Claims] 1. (a) Ethylene, (b) The following formula [I] or [II] ▲There are numerical formulas, chemical formulas, tables, etc.▼...[I] (In the formula, n is 0 or 1) , m is 0 or a positive integer, R^1 to R^1^8 are each independently a hydrogen atom, a halogen atom, or a hydrocarbon group, R^1^5 to R^1^8 may combine with each other to form a monocyclic or polycyclic ring, and the monocyclic or polycyclic ring may have a double bond, and R^1^5 and R^1^ With 6 or R^1^7
and R^1^8 may form an alkylidene group). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [II] [In the formula, l is an integer of 0 or 1 or more, m and n
is 0, 1 or 2, R^1 to R^1^5 are each independently a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group, an aromatic hydrocarbon group or an alkoxy group, and R^5
(or R^6) and R^9 (or R^7) may be bonded via an alkylene group having 1 to 3 carbon atoms,
Alternatively, they may be directly bonded without any group intervening. ] At least one cyclic olefin selected from the group consisting of unsaturated monomers represented by A cyclic olefin-based random copolymer is copolymerized in a liquid phase consisting of a cyclic olefin, and this cyclic olefin-based random copolymer is granulated, and the resulting pellets are dried to form a cyclic olefin-based random copolymer. When producing polymer pellets, granulation process of cyclic olefin random copolymer and/or
Alternatively, a method for producing cyclic olefin random copolymer pellets, the method comprising the step of separating and removing fine powder generated in the step of drying the pellets. 2. The method according to claim 1, wherein the operation of separating and removing the fine powder is performed using a classifier.