Patent US4065437A successfully refreshed from Google Patents.
US4065437A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aromatic polyether-sulfones
Assignee: BASF SE
•
Filing: 1976-10-12
•
Granted: 1977-12-27
•
Expires: 1996-10-12
Abstract
Abstract New thermoplastic polymers based on aromatic polyether-sulfones, which have molecular weights of from about 15,000 to 35,000 and contain units of the formula ##STR1## and a process for their manufacture.
Inventors
- 👤 Gerd Blinne
- 👤 Claus Cordes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:44
CPC Classifications
C; C08; C08G; C08G75/00; C08G75/20; C08G75/23
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
58 words
An aromatic polyethersulfone having repeating units of the formula (Ia) ##STR6## where Y is selected from the group consisting of ##STR7## individual Y's being identical or different, n is an integer of from 20 to 250, and the terminal groups being selected from the group consisting of hydroxy, alkoxy of 1 to 5 carbon atoms, F and Cl.
Claim 2
Dependent Claim
58 words
An aromatic polyethersulfone having repeating units of the formula (Ia) ##STR6## where Y is selected from the group consisting of ##STR7## individual Y's being identical or different, n is an integer of from 20 to 250, and the terminal groups being selected from the group consisting of hydroxy, alkoxy of 1 to 5 carbon atoms, F and Cl.
Claim 3
Dependent Claim
22 words
An aromatic polyethersulfone as claimed in claim 1, wherein the terminal groups are selected from the group consisting of methoxy and --Cl.
Claim 4
Dependent Claim
15 words
An aromatic polyethersulfone as claimed in claim 1, in which n is 25 to 40.
Claim 5
Dependent Claim
18 words
An aromatic polyethersulfone as claimed in claim 1, wherein the repeating units consist exclusively of said units (Ia).
Claim 6
Dependent Claim
34 words
An aromatic polyethersulfone as claimed in claim 1, wherein the repeating units consist exclusively of said units (Ia), and said terminal groups are predominantly members selected from the group consisting of chlorine and methoxy.
Claim 7
Dependent Claim
51 words
A process for the preparation of an aromatic polyethersulfone as defined in claim 1, which comprises condensing a dialkali metal salt of di-(4-hydroxyphenyl)-sulfone with a compound selected from the group consisting of ##STR8## in a molar ratio of from 0.9 to 1.1:1 at a temperature of from 200° to 350° C.
Claim 8
Dependent Claim
53 words
A process as claimed in claim 6, wherein the condensation is carried out in presence of such an amount of a polar aprotic solvent selected from the group consisting of dimethylsulfoxide and sulfolane in an amount such that a polyethersulfone solution having a solids content of 20% to 70% by weight is formed.
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) | 1980-12-26 | 1981-06-27 | 1981-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-26 | 1985-06-27 | 1985-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-26 | 1989-06-27 | 1989-12-27 | $7700.00 | Window Closed / Lapsed |