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Patent US4684409A successfully refreshed from Google Patents.
US4684409A
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US
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Solvent system comprising N-alkyl substituted amide and quaternary ammonium compound
Assignee: EIDP Inc
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Filing: 1986-01-17
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Granted: 1987-08-04
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Expires: 2006-01-17
Abstract
Abstract A process and its product are disclosed whereby poly-p-phenylene terephthalamide is prepared in a polymerization solvent comprising an N-alkyl-substituted amide, preferably N-methyl-2-pyrrolidone, and a quaternary ammonium chloride, preferably methyl-tri-n-butylammonium chloride.
Inventors
- 👤 James D. Hodge
- 👤 Kiu-Seung Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:04
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/12; C08G63/40; C08G63/44; C08G69/00; C08G69/02; C08G69/26; C08G69/28; C08G69/32
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
58 words
A solvent system for use in solution polymerization of aromatic polyamides comprising: (a) an N-alkyl-substituted amide selected from the group consisting of N-methyl pyrrolidone, dimethyl acetamide, and tetramethyl urea and (b) an effective amount of a quaternary ammonium compound selected from the group consisting of methyl tri-n-butylammonium chloride, methyl tri-n-propyl ammonium chloride, tetra-n-butylammonium chloride, and tetra-n-propyl ammonium chloride.
Claim 2
Dependent Claim
58 words
A solvent system for use in solution polymerization of aromatic polyamides comprising: (a) an N-alkyl-substituted amide selected from the group consisting of N-methyl pyrrolidone, dimethyl acetamide, and tetramethyl urea and (b) an effective amount of a quaternary ammonium compound selected from the group consisting of methyl tri-n-butylammonium chloride, methyl tri-n-propyl ammonium chloride, tetra-n-butylammonium chloride, and tetra-n-propyl ammonium chloride.
Claim 3
Dependent Claim
27 words
The solvent system of claim 1 wherein the quaternary ammonium chloride is present in an amount which is at least 1 weight percent of the N-alkyl-substituted amide.
Claim 4
Dependent Claim
28 words
The solvent system of claim 1 wherein the quaternary ammonium chloride is present in the amount which is from 1 to 100 weight percent of the N-alkyl-substituted amide.
Claim 5
Dependent Claim
29 words
The solvent system of claim 1 additionally comprising, (c) a tertiary amine acid acceptor in an amount which is from 0.5 to 75 weight percent of the N-alkyl-substituted amide.
References Cited (Backward Citations)
US4045417A
Cited
US4172938A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-03 | 1991-02-02 | 1991-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-03 | 1995-02-02 | 1995-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-03 | 1999-02-02 | 1999-08-04 | $7700.00 | Window Closed / Lapsed |