US4098754A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of high molecular thermoplastic polycarbonates of low flammability
Assignee: Bayer AG
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Filing: 1975-12-11
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Granted: 1978-07-04
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Expires: 1995-12-11
Abstract
Abstract The present invention is concerned with a process for the production of high molecular weight thermoplastic ppolycarbonates having improved flame resistance and in conjunction with glass fibres, improved mechanical properties and the polycarbonates so produced. A solution polycarbonate is reacted with an alkali metal salt soluble in the melt of the polycarbonate until the Staudinger Index has increased by about 3 to 30 cm 3 /g. This usually requires about 0.0001 to 0.1 wt. % of the salt, based on the weight of polycarbonate and a temperature of about 250° to 400° C for between about 1 and 30 minutes. In a preferred embodiment the reaction is conducted in a self-cleaning twin screw extruder.
Inventors
- 👤 Dieter Neuray
- 👤 Hugo Vernaleken
- 👤 Claus Wulff
- 👤 Ralf Lange
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:52
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/42; C08G64/04; C08G64/06; C08K; C08K5/00; C08K5/04; C08K5/09; C08K5/098; C08K5/16; Y; Y10; Y10S; Y10S260/00; Y10S260/24
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
120 words
A process for preparing a polycarbonate comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate with a basic alkali metal salt of an organic compound selected from the group consisting of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, a linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with one to 12 carbon atoms, and a mono- to tetrahydric phenol, which is soluble in the melt, at an elevated temperature between about 280° and 380° C., until the resulting polycarbonate has Staudinger Index (measured in methylene chloride at 25° C.) which is from about 3 to 30 cm 3 /g higher than the original polycarbonate.
Claim 2
Dependent Claim
120 words
A process for preparing a polycarbonate comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate with a basic alkali metal salt of an organic compound selected from the group consisting of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, a linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with one to 12 carbon atoms, and a mono- to tetrahydric phenol, which is soluble in the melt, at an elevated temperature between about 280° and 380° C., until the resulting polycarbonate has Staudinger Index (measured in methylene chloride at 25° C.) which is from about 3 to 30 cm 3 /g higher than the original polycarbonate.
Claim 3
Dependent Claim
28 words
The process according to claim 1 wherein the Staudinger Index of the resulting polycarbonate is from about 3 to 15 cm 3 /g higher than the original polycarbonate.
Claim 4
Dependent Claim
120 words
A process for the preparation of a higher molecular weight thermoplastic aromatic polycarbonate which comprises reacting in a self-cleaning twin-screw extruder an aromatic solution polycarbonate with from about 0.0001 to 0.1% by weight, relative to the solution polycarbonate, of a basic alkali metal salt of an organic compound selected from the group consisting of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, a linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with 1 to 12 carbon atoms, and a mono- to tetrahydric phenol which is soluble in the polycarbonate melt, at a temperature between about 280° and 380° C., for a period of from about 1 to 30 minutes.
Claim 5
Dependent Claim
120 words
A process for the preparation of a higher molecular weight thermoplastic aromatic polycarbonate which comprises reacting in a self-cleaning twin-screw extruder an aromatic solution polycarbonate with from about 0.0001 to 0.1% by weight, relative to the solution polycarbonate, of a basic alkali metal salt of an organic compound selected from the group consisting of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, a linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with 1 to 12 carbon atoms, and a mono- to tetrahydric phenol which is soluble in the polycarbonate melt, at a temperature between about 280° and 380° C., for a period of from about 1 to 30 minutes.
Claim 6
Dependent Claim
21 words
The process according to claim 1 wherein the solution polycarbonate contains at least 70 mol % of units derived from 2,2-bis-(4-hydroxyphenyl)-propane.
Claim 7
Dependent Claim
21 words
The process according to claim 1 wherein the solution polycarbonate is a copolymer of 2,2-bis-(4-hydroxyphenyl)-propane and another copolymerizable aromatic dihydroxy compound.
Claim 8
Dependent Claim
32 words
The process according to claim 4 wherein the solution polycarbonate contains from 0.05 to 2.0 mol % based on dihydroxy starting component, of branched units derived from a tri- or polyhydroxy compound.
Claim 9
Dependent Claim
26 words
The process according to claim 1 wherein the solution polycarbonate has an initial weight average molecular weight of from 10,000 to 200,000 as determined by light-scattering.
Claim 10
Dependent Claim
30 words
The process according to claim 1 wherein the solution polycarbonate has an initial Staudinger Index (measured in methylene chloride at 25° C.) of from 21 to 250 cm 3 /g.
Claim 11
Dependent Claim
108 words
A process for preparing a polycarbonate comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt, which is soluble in the melt, of an organic compound at an elevated temperature between about 280° and 380° C. until the resulting polycarbonate has a Staudinger Index (measured in methylene chloride at 25° C.) which is from about 3 to 30 cm 3 /g higher than the original polycarbonate and reinforcing the molding composition with about 10-40% by weight, relative to the total molding composition, of glass fibers.
Claim 12
Dependent Claim
108 words
A process for preparing a polycarbonate comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt, which is soluble in the melt, of an organic compound at an elevated temperature between about 280° and 380° C. until the resulting polycarbonate has a Staudinger Index (measured in methylene chloride at 25° C.) which is from about 3 to 30 cm 3 /g higher than the original polycarbonate and reinforcing the molding composition with about 10-40% by weight, relative to the total molding composition, of glass fibers.
Claim 13
Dependent Claim
83 words
The process according to claim 9 wherein said alkali metal salt is an alkali metal salt of an aliphatic, aromatic or aromatic-aliphatic mono- or dibasic, optionally halogenated, carboxylic acid containing from 1 to 24 carbon atoms per molecule, or of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, or of a linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with 1 to 12 carbon atoms, or of a mono- to tetrahydric phenol.
Claim 14
Dependent Claim
128 words
A polycarbonate prepared by a process comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt of an organic compound selected from the group consisting of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with 1 to 12 carbon atoms, or of a mono- to tetrahydric phenol which is soluble in the melt, at an elevated temperature between about 280° and 380° C. until the resulting polycarbonate has a Staudinger Index which is from about 3 to 30 cm 3 /g higher than the original polycarbonate.
Claim 15
Dependent Claim
128 words
A polycarbonate prepared by a process comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt of an organic compound selected from the group consisting of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with 1 to 12 carbon atoms, or of a mono- to tetrahydric phenol which is soluble in the melt, at an elevated temperature between about 280° and 380° C. until the resulting polycarbonate has a Staudinger Index which is from about 3 to 30 cm 3 /g higher than the original polycarbonate.
Claim 16
Dependent Claim
132 words
A molded article formed from a polycarbonate prepared by a process comprising reacting in self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt of an organic compound selected from the group consisting of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, a linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with 1 to 12 carbon atoms, and a mono- to tetrahydric phenol which is soluble in the melt, at an elevated temperature between about 280° and 380° C., until the resulting polycarbonate has a Staudinger Index which is from about 3 to 30 cm 3 /g higher than the original polycarbonate.
Claim 17
Dependent Claim
132 words
A molded article formed from a polycarbonate prepared by a process comprising reacting in self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt of an organic compound selected from the group consisting of a carboxylic acid amide or imide containing up to 24 carbon atoms per molecule, a linear or branched aliphatic, cycloaliphatic or araliphatic monohydric to tetrahydric, optionally halogenated, alcohol with 1 to 12 carbon atoms, and a mono- to tetrahydric phenol which is soluble in the melt, at an elevated temperature between about 280° and 380° C., until the resulting polycarbonate has a Staudinger Index which is from about 3 to 30 cm 3 /g higher than the original polycarbonate.
Claim 18
Dependent Claim
108 words
A polycarbonate prepared by a process comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt, which is soluble in the melt, of an organic compound at an elevated temperature between about 280° and 380° C. until the resulting polycarbonate has a Staudinger Index (measured in methylene chloride at 25° C.) which is from about 3 to 30 cm 3 /g higher than the original polycarbonate and reinforcing the molding composition with about 10-40% by weight, relative to the total molding composition, of glass fibers.
Claim 19
Dependent Claim
108 words
A polycarbonate prepared by a process comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt, which is soluble in the melt, of an organic compound at an elevated temperature between about 280° and 380° C. until the resulting polycarbonate has a Staudinger Index (measured in methylene chloride at 25° C.) which is from about 3 to 30 cm 3 /g higher than the original polycarbonate and reinforcing the molding composition with about 10-40% by weight, relative to the total molding composition, of glass fibers.
Claim 20
Dependent Claim
113 words
A molded article formed from a polycarbonate prepared by a process comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt, which is soluble in the melt, of an organic compound at an elevated temperature between about 280 and 380° C. until the resulting polycarbonate has a Staudinger Index (measured in methylene chloride at 25° C.) which is from about 3 to 30 cm 3 /g higher than the original polycarbonate and reinforcing the molding composition with about 10-40% by weight, relative to the total molding composition, of glass fibers.
Claim 21
Dependent Claim
113 words
A molded article formed from a polycarbonate prepared by a process comprising reacting in a self-cleaning twin-screw extruder the melt of a solution polycarbonate having a weight average molecular weight, M w , of about 10,000 to 200,000 with a basic alkali metal salt, which is soluble in the melt, of an organic compound at an elevated temperature between about 280 and 380° C. until the resulting polycarbonate has a Staudinger Index (measured in methylene chloride at 25° C.) which is from about 3 to 30 cm 3 /g higher than the original polycarbonate and reinforcing the molding composition with about 10-40% by weight, relative to the total molding composition, of glass fibers.
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) | 1981-07-03 | 1982-01-02 | 1982-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-03 | 1986-01-02 | 1986-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-03 | 1990-01-02 | 1990-07-04 | $7700.00 | Window Closed / Lapsed |