Patent EP0391633A2 successfully refreshed from Google Patents.
EP0391633A2
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EP
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Extrusion process of polyimide and polyimide pellet used for the process
Assignee: Mitsui Toatsu Chemicals Inc
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Filing: 1990-04-02
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Granted: —
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Expires: 2010-04-02
Abstract
Abstract Polyimide which is obtained by polymerization and consists essentially of recurring structural units of the formula (I): wherein X is a single bond or a hexafluoroisopropylidene group, is processed to a form of pellet, followed by heat-treating to obtain crystallinity of 5 % or more, and fed to an extruder to obtain articles.
Inventors
- 👤 Masumi Saruwatari
- 👤 Yasuhiro Fujii
- 👤 Syoichi Tsuji
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 23:10
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/022; C; C08; C08J; C08J3/00; C08J3/12; B29B; B29B9/00; B29B9/02; B29B9/06; B29B9/10; B29B9/12; B29C48/03; B29C48/04; B29C48/05; B29C48/06; B29C48/07; B29C48/08; B29C48/09; B29C48/10; B29C48/25; B29C48/78; B29C48/793; B29C48/80; B29C48/83; B29C48/832; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067; C08G73/1071; B29K; B29K2079/00; C08J2379/00; C08J2379/04; C08J2379/08
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
61 words
A process for extruding polyimide comprising the steps of pelletizing a polyimide consisting essentially of recurring structural units represented by the formula (I) wherein X is a single bond or a hexafluoroisopropylidene group, conducting heat-treatment of the resulting pellets to obtain a crystalline polyimide having a crystallinity of 5 % or more and feeding the crystalline polyimide pellets to an extruder.
Claim 2
Dependent Claim
61 words
A process for extruding polyimide comprising the steps of pelletizing a polyimide consisting essentially of recurring structural units represented by the formula (I) wherein X is a single bond or a hexafluoroisopropylidene group, conducting heat-treatment of the resulting pellets to obtain a crystalline polyimide having a crystallinity of 5 % or more and feeding the crystalline polyimide pellets to an extruder.
Claim 3
Dependent Claim
19 words
The process of claim 1 wherein the heat-treatment is conducted at a temperature of from 250 to 370 °C.
Claim 4
Dependent Claim
14 words
The process of claim 1 wherein the crystallinity is from 5 to 50 %.
Claim 5
Dependent Claim
45 words
A polyimide pellet for use in an extrusion process comprising polyimide consisting essentially of recurring structural units represented by the formula (I): wherein X is a single bond or a hexafluoroisopropylidene group, and wherein the polyimide pellet has a crystallinity of 5 % or more.
Claim 6
Dependent Claim
45 words
A polyimide pellet for use in an extrusion process comprising polyimide consisting essentially of recurring structural units represented by the formula (I): wherein X is a single bond or a hexafluoroisopropylidene group, and wherein the polyimide pellet has a crystallinity of 5 % or more.
Claim 7
Dependent Claim
15 words
The polyimide pellet of claim 4 wherein the crystallinity is from 5 to 50 %.
References Cited (Backward Citations)
No citation records indexed.
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