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US4338429A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for working up polycarbonates

Assignee: Bayer AG
•
Filing: 1980-07-07
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Granted: 1982-07-06
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Expires: 2000-07-07
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Abstract

Abstract The present invention relates to a process for working up alkaline two-phase mixtures which have been obtained in the synthesis of polycarbonates by the two-phase boundary process, characterized in that for the separation of the alkaline two-phase mixture into an organic phase and an aqueous phase, the mixture is supplied with shearing energy and/or added are one or more cationic emulsifying agents and/or dispersing agents and/or in that, for the separation of the acidified two-phase mixture into an organic phase and an aqueous phase, the mixture is supplied with shearing energy and/or added are one or more cationic emulsifying agents and/or dispersing agents and/or in that the organic phase which was separated off after the acidification is washed with water to which one or more water-soluble, organic anionic compounds have been added.

Inventors

  • 👤 Volker Serini
  • 👤 John Goossens
  • 👤 Ludwig Bottenbruch
  • 👤 Dieter Freitag

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 12:01
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/22; C08G64/24; C08G64/40; C08G64/406

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 125 words
In the process for working up two-phase mixtures which are obtained in the course of the synthesis of polycarbonates by the two-phase boundary process, the improvement comprising one or more of the steps of (i) promoting the separation of the acidic two-phase mixture resulting from the acidification of the organic phase obtained by separation from alkaline two-phase mixture into an organic phase and an aqueous phase by the addition of one or more cationic emulsifying agents and/or dispersing agents and, optionally, by the application of shear energy; and, (ii) promoting the separation of the two-phase mixture resulting from water washing of the organic phase obtained by separation of the acidic two-phase mixture by adding one or more water-soluble organic anionic compounds to the wash water.
Claim 2
Dependent Claim 125 words
In the process for working up two-phase mixtures which are obtained in the course of the synthesis of polycarbonates by the two-phase boundary process, the improvement comprising one or more of the steps of (i) promoting the separation of the acidic two-phase mixture resulting from the acidification of the organic phase obtained by separation from alkaline two-phase mixture into an organic phase and an aqueous phase by the addition of one or more cationic emulsifying agents and/or dispersing agents and, optionally, by the application of shear energy; and, (ii) promoting the separation of the two-phase mixture resulting from water washing of the organic phase obtained by separation of the acidic two-phase mixture by adding one or more water-soluble organic anionic compounds to the wash water.
Claim 3
Dependent Claim 37 words
The process according to claim 1, characterized in that the cationic emulsifying agents and dispersing agents are employed in amounts of 10 to 10,000 ppm, relative to the weight of the aqueous phase of the two-phase mixture.
Claim 4
Dependent Claim 37 words
The process according to claim 1, characterized in that the cationic emulsifying agents and dispersing agents are employed in amounts of 100 to 1,000 ppm, relative to the weight of the aqueous phase of the two-phase mixture.
Claim 5
Dependent Claim 35 words
The process according to claim 1, characterized in that the water-soluble, organic anionic compounds are employed in amounts of 0.1 to 1,000 ppm, relative to the weight of the aqueous phase of the two-phase mixture.
Claim 6
Dependent Claim 35 words
The process according to claim 1, characterized in that the water-soluble organic, anionic compounds are employed in amounts of 5 to 100 ppm, relative to the weight of the aqueous phase of the two-phase mixture.
Claim 7
Dependent Claim 87 words
In the process for working up two-phase mixtures which are obtained in the course of the synthesis of polycarbonates characterized in that they contain at least 50% by weight units derived from 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane, by the two-phase boundary process, the improvement in promoting the separation of the alkaline two-phase mixture, obtained upon completion of the synthesis reaction, into an organic phase and an aqueous phase consisting essentially of the addition of one or more cationic emulsifying agents and/or dispersing agents and optionally by the application of shearing energy.
Claim 8
Dependent Claim 87 words
In the process for working up two-phase mixtures which are obtained in the course of the synthesis of polycarbonates characterized in that they contain at least 50% by weight units derived from 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane, by the two-phase boundary process, the improvement in promoting the separation of the alkaline two-phase mixture, obtained upon completion of the synthesis reaction, into an organic phase and an aqueous phase consisting essentially of the addition of one or more cationic emulsifying agents and/or dispersing agents and optionally by the application of shearing energy.
Claim 9
Dependent Claim 90 words
In the process for working up two-phase mixtures which are obtained in the course of the synthesis of polycarbonates by the two-phase boundary process wherein the alkaline two-phase mixture is separated into an organic phase and an aqueous phase, and said organic phase having then been acidified by aqueous acid, the improvement comprising promoting the separation of said acidic two-phase mixture into an organic phase and an aqueous phase by the addition of one or more cationic emulsifying agents and/or dispersing agents and optionally by the application of shearing energy.
Claim 10
Dependent Claim 90 words
In the process for working up two-phase mixtures which are obtained in the course of the synthesis of polycarbonates by the two-phase boundary process wherein the alkaline two-phase mixture is separated into an organic phase and an aqueous phase, and said organic phase having then been acidified by aqueous acid, the improvement comprising promoting the separation of said acidic two-phase mixture into an organic phase and an aqueous phase by the addition of one or more cationic emulsifying agents and/or dispersing agents and optionally by the application of shearing energy.
Claim 11
Dependent Claim 97 words
In the process for working up two-phase mixtures which are obtained in the course of the synthesis of polycarbonates by the two-phase boundary process wherein the alkaline two-phase mixture is separated into an organic phase and an aqueous phase and said organic phase is acidified and separated into a second organic phase and an aqueous phase, said second organic phase having then been washed with water, the improvement comprising promoting the separation of the two-phase mixture of said second organic phase and wash water by adding one or more water-soluble organic anionic compounds to said wash water.
Claim 12
Dependent Claim 97 words
In the process for working up two-phase mixtures which are obtained in the course of the synthesis of polycarbonates by the two-phase boundary process wherein the alkaline two-phase mixture is separated into an organic phase and an aqueous phase and said organic phase is acidified and separated into a second organic phase and an aqueous phase, said second organic phase having then been washed with water, the improvement comprising promoting the separation of the two-phase mixture of said second organic phase and wash water by adding one or more water-soluble organic anionic compounds to said wash water.

References Cited (Backward Citations)

GB963322A Cited
DE1645054U Cited
US3275601A Cited
US3143525A Cited
US3294741A Cited
US3184431A Cited
US3879348A Cited
US3879347A Cited
DE2901665A1 Cited
DE2901668A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-07-05 1986-01-04 1986-07-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-07-05 1990-01-04 1990-07-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-07-05 1994-01-04 1994-07-06 $7700.00 Window Closed / Lapsed

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