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US4299948A Expired / Lapsed US ⏱️ 0.0 years remaining

Macrocyclic polycarbonates

Assignee: Bayer AG
•
Filing: 1979-11-26
•
Granted: 1981-11-10
•
Expires: 1999-11-26
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Abstract

Abstract The subject of the instant invention are polycarbonates based on diphenols of the formula I ##STR1## wherein Y is a single bond, an elkylene- or alkylidene-radical with 1 to 7 carbon atoms, a cycloalkylene- or cycloalkylidene-radical with 5 to 12 carbon atoms, ##STR2## which have weight average molecular weights (M LS ) measured by light scattering of at least 15 000 and which are characterized in having an average of zero to 1.5 mols, preferably 0.3 to 1.0 mols and especially 0.3 to 0.8 mols endgroups per mol polycarbonate. The subject of instant invention is also a process for preparing these polycarbonates according to the interfacial polycondensation method, the polycarbonates thus obtained and the use of the polycarbonates according instant invention for the preparation of compounds and films.

Inventors

  • 👤 Kurt Weirauch
  • 👤 Alfred Horbach
  • 👤 Hugo Vernaleken

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 17:08
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/26; C07; C07C; C07C68/00; C07C68/02

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 74 words
Polycarbonates incorporating residues of diphenols of the formula (I) ##STR5## in which Y denotes a single bond, an alkylene or alkylidene radical with 1-7 C atoms, a cycloalkylene or cycloalkylidene radical with 5-2 C atoms, --O--, --S--, ##STR6## which have weight average molecular weights M LS , measured by light scattering, of at least 15,000, which are characterised in that the polycarbonates exhibit on average 0 to 1.5 mols end groups per mol polycarbonate.
Claim 2
Dependent Claim 74 words
Polycarbonates incorporating residues of diphenols of the formula (I) ##STR5## in which Y denotes a single bond, an alkylene or alkylidene radical with 1-7 C atoms, a cycloalkylene or cycloalkylidene radical with 5-2 C atoms, --O--, --S--, ##STR6## which have weight average molecular weights M LS , measured by light scattering, of at least 15,000, which are characterised in that the polycarbonates exhibit on average 0 to 1.5 mols end groups per mol polycarbonate.
Claim 3
Dependent Claim 23 words
Polycarbonates according to claim 1, characterised in that the polycarbonates contain, on the average, 0.3 to 1.0 mols end groups per mol polycarbonate.
Claim 4
Dependent Claim 23 words
Polycarbonates according to claim 1, characterised in that the polycarbonates contain, on the average, 0.3 to 0.8 mols end groups per mol polycarbonate.
Claim 5
Dependent Claim 12 words
Polycarbonates according to claim 1, 2 or 3, incorporating residues of 2,2-bis-(4-hydroxyphenyl)-propane.
Claim 6
Dependent Claim 12 words
Moldings and films comprising the polycarbonate of claim 1, 2 or 3.

References Cited (Backward Citations)

US3275601A Cited
US3220975A Cited
US3386954A Cited
US3221025A Cited
US4129574A Cited
US4139687A Cited
US4197394A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-11-09 1985-05-11 1985-11-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-11-09 1989-05-11 1989-11-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-11-09 1993-05-11 1993-11-10 $7700.00 Window Closed / Lapsed

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