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公开(公告)号：JPH04332726A
公开(公告)日：1992-11-19
申请号：JP19896591
申请日：1991-05-08
Applicant: DAICEL CHEM
Inventor： YAMATO TSUTOMU , OKANO YOSHIMICHI
IPC: C08G64/20
Abstract: PURPOSE:To obtain a polymer having faint color at a low cost by producing a prepolymer using a reactor having a liquid-contacting part made of a material containing less than specific amount of iron, adding a discoloration-preventing agent and carrying out polycondensation until the viscosity-average molecular weight of the polymer reaches a prescribed range. CONSTITUTION:The polycarbonate is produced by the ester-interchange melt- polycondensation reaction of a bivalent hydroxy compound (e.g. bisphenol A) with a bisaryl carbonate in the presence of an ester-interchange catalyst (e.g. lithium borohydride). In the above process, the liquid-contacting part of the reactor is made of a material having an iron-content of
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公开(公告)号：JPH02284917A
公开(公告)日：1990-11-22
申请号：JP10701589
申请日：1989-04-26
Applicant: DAICEL CHEM
Inventor： SUGANO TATSUYA , YAMATO TSUTOMU
Abstract: PURPOSE:To obtain in high efficiency the title polymer of high molecular weight without the need for using phosgene by reaction in the presence of a specific catalyst between a dialkyl carbonate and a compound prepared by diesterification of the hydroxyl groups of an aromatic dihydroxyl compound. CONSTITUTION:Firstly, a reaction is carried out between (A) a dialkyl carbonate (pref. dimethyl carbonate) and (B) a compound prepared by diesterification of the hydroxyl groups of an aromatic dihydroxyl compound (pref. bisphenol A diacetate) in the presence of a catalyst of formula MBHnR4-n (M is alkali metal; R is hydrocarbon, phenoxy, etc.; n is 0-4) (pref. KBH4) to obtain an oligomer of the formula (R1 is alkyl; Ac is acyloxy; BP is residue resulted from eliminating hydroxyl group from bisphenol; m is 1-10; x+y=2). Thence, the oligomer is reacted in the presence of the above-mentioned catalyst to obtain the objective polymer.
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公开(公告)号：JPH02284916A
公开(公告)日：1990-11-22
申请号：JP10701489
申请日：1989-04-26
Applicant: DAICEL CHEM
Inventor： SUGANO TATSUYA , YAMATO TSUTOMU
Abstract: PURPOSE:To obtain in an industrially advantageous manner a highmolecular weight polycarbonate of favorable hue without the need for using highly toxic phosgene by reaction between a dialkyl carbonate and an aromatic dihydroxyl compound using a specific compound as ester interchange catalyst. CONSTITUTION:The objective polycarbonate can be obtained by reaction between (A) a dialkyl carbonate (pref. dimethyl carbonate) and (B) an aromatic dihydroxyl compound [e.g. 2,2-bis(4-hydroxyphenyl)propane] using, as ester interchange catalyst, a compound of formula MBHnR4-n [M is alkali (alkaline earth) metal; R is alkyl, phenyl, alkoxyl or phenoxy; n is 0-4] (e.g. LiBH4).
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公开(公告)号：JPH0260927A
公开(公告)日：1990-03-01
申请号：JP21426188
申请日：1988-08-29
Applicant: DAICEL CHEM
Inventor： YAMATO TSUTOMU , NISHIMURA KOJI
Abstract: PURPOSE:To reduce the remaining by-product salt by bringing a mixture contg. a polymerized arom. polyether into contact with a non-solvent of the polymer after it is filtered. CONSTITUTION:By-products are removed by filtering a soln. of a mixture contg. an arom. polyether after the polymer is syntersized (e.g., polycondensation of dihydroxydiphenyl and dichlorodiphenyl sulfone). It is pref. here that the concn. of the polymer is 15-50wt.%, the filtration temp. is 70-180 deg.C and the filtration fineness is 5-50mum (it is performed by filtering at the first stage of 10-100mum and at the second stage of 1-10mum). Then, the by-products are dissolved and water or an org. solvent which is a non-solvent for the arom. polyether, e.g., methanol, is used for washing to reduce the content of the by-products to about 10-100ppm.
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公开(公告)号：JPH0892365A
公开(公告)日：1996-04-09
申请号：JP12701891
申请日：1991-03-13
Applicant: DAICEL CHEM
Inventor： YAMATO TSUTOMU , FUKUDA YUTAKA
Abstract: PURPOSE: To efficiently obtain a colorless transparent and high-molecular weight polycarbonate by melt polycondensation through transesterification between a dihydric hydroxy compound and a bisaryl carbonate for a specific residence time in the later condensation process. CONSTITUTION: A melt polycondensation is carried out through transesterification between (A) a dihydric hydroxy compound of pref. formula I, II or III (R1 -R4 are each H, a 1-8C alkyl or phenyl; X is a halogen; (n) is 0-4; (m) is 1-4) and (B) a bisaryl carbonate (pref. diphenyl-carbonate). In this case, the intermediately formed polycarbonate 5000-20000 in viscosity-average molecular weight is subjected to polycondensation reaction in the later condensation process for a residence time of 15-60min, thus obtaining the objective polycarbonate. It is preferable that the latter polycondensation reaction be conducted 0.1-50mm in the thickness of the liquor in the reaction region during the later condensation process.
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Patent Agency Ranking
公开(公告)号：JPH05156000A
公开(公告)日：1993-06-22
申请号：JP32579191
申请日：1991-12-10
Applicant: DAICEL CHEM
Inventor： OSHINO YASUHIRO , YAMATO TSUTOMU
Abstract: PURPOSE:To obtain a thermally stable polycarbonate by limiting the concentration of a monohydric phenol contained in a polycarbonate produced by a given process. CONSTITUTION:The objective polycarbonate is obtained by the melt polycondensation of a dihydroxy compound [e.g. 2,2-bis(4-hydroxyphenyl)propane] and a carbonic diester (e.g. diphenyl carbonate) in the presence of a transesterification catalyst (e.g. 4-dimethylaminopyridine) according to the transesterification process, wherein the concentration of a monohydric phenol contained is limited to 1000ppm or less. Further, preferably, the concentration of the dihydroxy compound as the starting material is limited to 1000ppm or less.
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公开(公告)号：JPH04332727A
公开(公告)日：1992-11-19
申请号：JP19896691
申请日：1991-05-08
Applicant: DAICEL CHEM
Inventor： YAMATO TSUTOMU , SUGANO TATSUYA
IPC: C08G64/20
Abstract: PURPOSE:To produce a colorless transparent polycarbonate having high molecular weight on an industrial scale in high efficiency by carrying out ester- interchange melt-polycondensation of a bivalent hydroxy compound and a bisaryl carbonate. CONSTITUTION:The polycarbonate prepolymer having a viscosity-average molecular weight of 5,000-20,000 and produced by a precondensation process in the presence of a solvent is subjected to a post-condensation process using one or more paddle-type self-cleaning twin-screw extruders to obtain a polycarbonate having high molecular weight.
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公开(公告)号：JPH04142329A
公开(公告)日：1992-05-15
申请号：JP26582890
申请日：1990-10-02
Applicant: DAICEL CHEM
Inventor： YAMATO TSUTOMU , KUWANA TAKAAKI
Abstract: PURPOSE:To obtain a colorless and transparent high-molecular weight polycarbonate at good efficiency by melting a starting monomer mixture in a preparation tank, polycondensing the monomer mixture in a tank reactor and increasing the viscosity-average molecular weight on a specified twin-screw extruder. CONSTITUTION:A process for producing a polycarbonate by melt-polycondensing a dihydroxyl compound [e.g. 2,2-bis-(4-hydroxyphenyl) propane] with a bisaryl carbonate (e.g. diphenyl carbonate) by transesrterification, wherein the above monomer are molten in a preparation tank (step 1), the molten monomer mixture is polycondensed in a tank reactor to obtain a polycarbonate of a viscosity- average molecular weight of 5000-30000 (step 2), and a polycarbonate of a viscosity-average molecular weight of 12000-60000 is obtained on a paddle-type self-cleaning twin-screw extruder (step 3). According to the above process, a colorless and transparent high-molecular weight polycarbonate can be produced at good efficiency.
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公开(公告)号：JPH04106124A
公开(公告)日：1992-04-08
申请号：JP22323590
申请日：1990-08-24
Applicant: DAICEL CHEM
Inventor： YAMATO TSUTOMU , SUGANO TATSUYA
Abstract: PURPOSE:To produce a polycarbonate having a high molecular weight and improved colorlessness, transparency and production efficiency by melt- polycondensing a dihydroxy compound with a bisaryl carbonate in four specified steps. CONSTITUTION:In step 1, a monomer comprising a dihydroxy compound and a bisaryl carbonate is polycondensed in a molten state in the presence of a transesterification catalyst in at least one horizontal reaction tank to obtain a polycarbonate prepolymer of a number-average molecular weight of 5000-20000. In step 2, the obtained prepolymer is received in at least one hold tank. In step 3, this prepolymer is polycondensed to obtain a polycarbonate of a viscosity-average molecular weight of 10000-30000 while the distillate such as the phenol formed by the reaction is removed on at least one preheater and a vacuum flashing chamber. In step 4, the obtained polycarbonate is treated with at least one paddle-type self-cleaning twin-screw extruder to obtain a polycondensate of a viscosity-average molecular weight of 12000-60000.
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公开(公告)号：JPH0488017A
公开(公告)日：1992-03-19
申请号：JP20439490
申请日：1990-08-01
Applicant: DAICEL CHEM
Inventor： YAMATO TSUTOMU , OSHINO YASUHIRO
IPC: C08G64/20
Abstract: PURPOSE:To obtain the subject high-molecular weight colorless and transparent polycarbonate suitable for injection molding by carrying out ester interchange reaction using a material having a specific content or below of iron as a material for a reactor. CONSTITUTION:(A) A dihydric hydroxy compound and (B) a bisaryl carbonate are subjected melt polymerization in the presence of an ester interchange catalyst according to an ester interchange method. In the process, a material (e.g. Monel metal) with
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