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US5169929A
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Lithium/hmpa-promoted synthesis of poly(phenylenes)
Assignee: University of South Carolina
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Filing: 1990-06-25
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Granted: 1992-12-08
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Expires: 2010-06-25
Abstract
Abstract Poly(phenylene) that is substantially free of insoluble material is prepared by the polymerization of a lithioarylhalide compound in the presence of a polar aprotic compound such as hexamethylphosphoramide, N,N,N',N'-tetramethylethylenediamine or hexamethylphosphorous triamide. The preferred reaction involves the polymerization of 1-bromo-4-lithiobenzene in the presence of hexamethylphosphoramide. The 1-bromo-4-lithiobenzene may be synthesized by reacting 1,4-dibromobenzene with t-butyllithium. These same types of reactions can also be used to synthesis other benzenoid polymers.
Inventors
- 👤 James M. Tour
- 👤 Eric B. Stephens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:54
CPC Classifications
C; C08; C08G; C08G61/00; C08G61/02; C08G61/10; C08G2261/00; C08G2261/30; C08G2261/31; C08G2261/312
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
27 words
A method of preparing a benzenoid polymer comprising polymerizing a lithioarylenehalide compound in the presence of a polar aprotic compound which is not decomposed by alkyllithium compounds.
Claim 2
Independent Claim
27 words
A method of preparing a benzenoid polymer comprising polymerizing a lithioarylenehalide compound in the presence of a polar aprotic compound which is not decomposed by alkyllithium compounds.
Claim 3
Independent Claim
22 words
A method according to 1, wherein the polar aprotic compound is selected from the group consisting of hexamethylphosphoramide, N,N,N',N'-tetramethyl-ethylenediamine and hexamethylphosphorous triamide.
Claim 4
Independent Claim
22 words
A method according to 1, wherein the polar aprotic compound is selected from the group consisting of hexamethylphosphoramide, N,N,N',N'-tetramethyl-ethylenediamine and hexamethylphosphorous triamide.
Claim 5
Dependent Claim
22 words
A method according to claim 1, wherein the benzenoid polymer is a para-poly(phenylene) and the polymer is prepared by polymerizing a paralithioarylenehalide.
Claim 6
Dependent Claim
25 words
A method according to claim 3, wherein the para-lithioarylhalide is selected from the group consisting of substituted and unsubstituted 1-halo-4-lithiobenzene and substituted and unsubstituted 4-halo-4'-lithiobiphenyl.
Claim 7
Dependent Claim
35 words
A method according to claim 1, further comprising the step of reacting a para-substituted aryldihalide with at least one equivalent of an alkyllithium that undergoes lithium halogen exchange to form the paralithioarylenehalide to be polymerized.
Claim 8
Dependent Claim
13 words
A method according to claim 5, wherein the polar aprotic compound is hexamethylphosphoramide.
Claim 9
Dependent Claim
12 words
A method according to claim 6, wherein the para-substituted aryldihalide is 1,4-dibromobenzene.
Claim 10
Dependent Claim
12 words
A method according to claim 5, wherein the alkyllithium compound is t-butyllithium.
Claim 11
Dependent Claim
18 words
A method according to claim 7, wherein at least two equivalents of alkyllithium are reacted with the 1,4-dibromobenzene.
Claim 12
Dependent Claim
12 words
A method according to claim 9, wherein the alkyllithium compound is t-butyllithium.
References Cited (Backward Citations)
US4576688A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-12-08 | 1996-06-08 | 1996-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-08 | 2000-06-08 | 2000-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-08 | 2004-06-08 | 2004-12-08 | $7700.00 | Window Closed / Lapsed |