Patent JPS62230367A successfully refreshed from Google Patents.
EP0046074A2
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Process for preparing polyimide solution
Assignee: Ube Corp
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Filing: 1981-08-07
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Granted: —
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Expires: 2001-08-07
Abstract
Abstract A polyimide solution is prepared by a process wherein a substantially equimolar mixture of a tetracarboxylic acid ingredient containing 2,3,3 min ,4 min -biphenyltetracarboxylic acid or its functional derivative in an amount of at least 70 mole % based on the total tetracarboxylic acid ingredient and an aromatic diamine ingredient is polymerized in an organic polar solvent at a temperature of 100 to 300 DEG C in a closed polymerization system, while adding water if necessary, until the water content in the polymer solution becomes constant. According to this process, a polyimide solution having a desired rotational viscosity can be produced with good reproducibility by a one-stage polymerization-imidation procedure.
Inventors
- 👤 Yoshikazu C/O Hirakata-Jushi-Kenkyusho Sasaki
- 👤 Hiroshi C/O Hirakata-Jushi-Kenkyusho Inoue
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 00:58
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1003; C08G73/1007; C08G73/1028; C08G73/1032
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
81 words
A process for preparing a polyimide solution which comprises polymerizing a substantially equimolar mixture of a tetracarboxylic acid ingredient containing 2,3,3',4'--biphenyltetracarboxylic acid or its functional derivative in an amount of at least 70 mole %, based on the total tetracarboxylic acid ingredient and an aromatic diamine ingredient in an organic polar solvent at a polymerization temperature of -100 to 300°C in a closed polymerization system, while adding water if necessary, until the water content in the polymer solution becomes substantially constant.
Claim 2
Dependent Claim
81 words
A process for preparing a polyimide solution which comprises polymerizing a substantially equimolar mixture of a tetracarboxylic acid ingredient containing 2,3,3',4'--biphenyltetracarboxylic acid or its functional derivative in an amount of at least 70 mole %, based on the total tetracarboxylic acid ingredient and an aromatic diamine ingredient in an organic polar solvent at a polymerization temperature of -100 to 300°C in a closed polymerization system, while adding water if necessary, until the water content in the polymer solution becomes substantially constant.
Claim 3
Dependent Claim
33 words
A process according -to claim 1 wherein the organic polar solvent is selected from the group consisting of N,N--diethylformamide, N,N-diethylacetamide, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethylmethoxy- acetamide, N-methyl-2-pyrrolidone, dimethylsulfoxide, hexamethylformamide, pyridine, dimethylsulfone, tetramethylene-sulfone, dimethyltetramethylene-sulfone, and sulforane.
Claim 4
Dependent Claim
27 words
A process according to claim 1 wherein the tetracarboxylic acid ingredient contains at least 75 mole %, based on the total tetracarboxylic acid ingredient, of 2,3,3',4'-biphenyltetracarboxylic dianhydride.
Claim 5
Dependent Claim
31 words
A process according to claim 1 wherein the aromatic diamine ingredient contains at least about 50 mole %, based on the total aromatic diamine ingredient, of a diphenyl type diamine compound.
Claim 6
Dependent Claim
19 words
A process according to claim 1 wherein the polymerization temperature is in the range of from 120 to 280°C.
Claim 7
Dependent Claim
34 words
A process according to claim 1 wherein water is added into the closed polymerization system in an amount of up to about 0.8 gram per gram of the polyimide formed in the polymer solution.
Claim 8
Dependent Claim
61 words
A process according to claim 1 or 6 wherein the partial pressure of water vapor in the closed polymerization system is maintained in the range of from 0.01 to 20 kg/cm 2 so that the water content in the polymer solution in the polymerization system be in the range of from 0.01 to 10% at the time of completion of polymerization.
Claim 9
Dependent Claim
74 words
A polyimide solution which has a rotational viscosity of 1 to 10,000 poises as measured at 140°C and contains 3 to 30% by weight of polyimide having a logarithmic viscosity of from 0.2 to 6 as measured at 50°C on a solution of a 0.5 g solution in 100 mt of p-chlorophenol and exhibiting an imidation ratio of at least about 90%, said polyimide solution being prepared by a process according to claim 1.
References Cited (Backward Citations)
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