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US4544713A
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Method for making heterocyclic block copolymer
Assignee: United States Department of the Air Force
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Filing: 1984-05-16
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Granted: 1985-10-01
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Expires: 2004-05-16
Abstract
Abstract Thermally stable aromatic heterocyclic block copolymers are prepared by reacting a diamino monomer and terephthalic acid to form a carboxy-terminated rigid rod segment and then polymerizing a carboxy-monoamine monomer therewith to form flexible segments grafted onto the rigid rod segments.
Inventors
- 👤 Tsu-tzu Tsai
- 👤 Fred E. Arnold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:22
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/08; C08G75/00; C08G75/32
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
116 words
A method for preparing a thermally stable aromatic heterocyclic block copolymer of the general formula ##STR4## wherein m is an integer equal to the number of repeating units of the rigid rod segment and n is an integer equal to the number of repeating units of the flexible end segments, which comprises the steps of (a) reacting 2,5-amino-1,4-dithiobenzene with terephthalic acid in polyphosphoric acid (PPA) under reaction conditions to form carboxy-terminated rigid rod segments; (b) adding an amino monomer of the general formula ##STR5## to the reaction mixture of PPA and rigid rod segments, and polymerizing said amino monomer to form flexible segments grafted onto said rigid rod segments; and (c) recovering the resulting block copolymer.
Claim 2
Independent Claim
116 words
A method for preparing a thermally stable aromatic heterocyclic block copolymer of the general formula ##STR4## wherein m is an integer equal to the number of repeating units of the rigid rod segment and n is an integer equal to the number of repeating units of the flexible end segments, which comprises the steps of (a) reacting 2,5-amino-1,4-dithiobenzene with terephthalic acid in polyphosphoric acid (PPA) under reaction conditions to form carboxy-terminated rigid rod segments; (b) adding an amino monomer of the general formula ##STR5## to the reaction mixture of PPA and rigid rod segments, and polymerizing said amino monomer to form flexible segments grafted onto said rigid rod segments; and (c) recovering the resulting block copolymer.
Claim 3
Dependent Claim
85 words
The method of claim 1 wherein said reaction step (a) is conducted at a temperature in the approximate range of 100° to 200° C. for a period of about 18 to 36 hours until said rigid rod segment has an inherent viscosity in methanesulfonic acid at room temperature in the approximate range of 8 to 31 dl/g and wherein said step (b) is conducted at a temperature in the approximate range of 100° to 250° C. for a period of about 12 to 36 hours.
Claim 4
Dependent Claim
19 words
The method of claim 1 wherein the relative proportion of rigid:flexible is in the approximate range 1:5 to 5:1.
Claim 5
Dependent Claim
18 words
The method of claim 3 wherein the ratio rigid:flexible is in the approximate range of 1:3 to 3:1.
Claim 6
Dependent Claim
22 words
The method of claim 1 wherein said recovery step (c) comprises precipitating said polymer in bulk from solution into a coagulating bath.
Claim 7
Dependent Claim
30 words
The method of claim 1 wherein said recovery step (c) comprises precipitating said polymer by extruding the reaction mixture of PPA and polymer through a spinnerette into a coagulating bath.
Claim 8
Independent Claim
116 words
A method for preparing a thermally stable aromatic heterocyclic block copolymer of the general formula ##STR6## wherein m is an interger equal to the number of repeating units of the rigid rod segment and n is an integer equal to the number of repeating units of the flexible end segments, which comprises the steps of (a) reacting 1.5-diamino-2.4-dithiabenzene with terephthalic acid in polyphosphoric acid (PPA) under reaction conditions to form carboxy-terminated rigid rod segments: (b) adding an amino monomer of the general formula ##STR7## to the reaction mixture of PPA and rigid rod segments, and polymerizing said amino monomer to form flexible segments grafted onto said rigid rod segments: and (c) recovering the resulting block copolymer.
Claim 9
Independent Claim
116 words
A method for preparing a thermally stable aromatic heterocyclic block copolymer of the general formula ##STR6## wherein m is an interger equal to the number of repeating units of the rigid rod segment and n is an integer equal to the number of repeating units of the flexible end segments, which comprises the steps of (a) reacting 1.5-diamino-2.4-dithiabenzene with terephthalic acid in polyphosphoric acid (PPA) under reaction conditions to form carboxy-terminated rigid rod segments: (b) adding an amino monomer of the general formula ##STR7## to the reaction mixture of PPA and rigid rod segments, and polymerizing said amino monomer to form flexible segments grafted onto said rigid rod segments: and (c) recovering the resulting block copolymer.
Claim 10
Dependent Claim
84 words
The method of claim 7 wherein said reaction step (a) is conducted at a temperature in the approximate range of 100° to 200° C. for a period of about 18 to 36 hours until said rigid rod segment has an inherent viscosity in methanesulfonic acid at room temperature in the approximate range of 8 to 31 dl/g and wherein step (b) is conduced at a temperature in the approximate range of 100° to 250° C. for a period of about 12 to 36 hours.
Claim 11
Dependent Claim
19 words
The method of claim 7 wherein the relative proportion of rigid:flexible is in the approximate range 1:5 to 5:1.
Claim 12
Dependent Claim
18 words
The method of claim 9 wherein the ratio rigid-flexible is in the approximate range of 1:3 to 3:1.
Claim 13
Dependent Claim
22 words
The method of claim 7 wherein said recovery step (c) comprises precipitating said polymer in bulk from solution into a coagulating bath.
Claim 14
Dependent Claim
30 words
The method of claim 7 wherein said recovery step (c) comprises precipitating said polmer by extruding the reaction mixture of PPA and polymer through a spinnerette into a coagulating bath.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-30 | 1989-04-01 | 1989-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-30 | 1993-04-01 | 1993-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-30 | 1997-04-01 | 1997-10-01 | $7700.00 | Window Closed / Lapsed |