Patent US3400891A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4174437A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the preparation of branched polycarbonates

Assignee: Bayer AG
•
Filing: 1978-04-07
•
Granted: 1979-11-13
•
Expires: 1998-04-07
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The present invention relates to a process for the preparation of branched thermoplastic polycarbonates, characterized in that diphenols are completely reacted with about 0.05 to about 2.0 mol %, relative to mols of diphenols, of cyanuric chloride in a primary reaction, while controlling the pH and temperature and in the presence of a co-solvent, and thereafter the products are subjected to polycondensation, in accordance with known methods of the phase boundary process, to give high-molecular weight, branched polycarbonates. The invention further relates to the branched polycarbonates prepared by this process.

Inventors

  • 👤 Karsten Idel
  • 👤 Dieter Freitag
  • 👤 Werner Nouvertne

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 07:15
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/04; C08G64/06; C08K; C08K5/00; C08K5/36; C08K5/41; C08K5/42

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 74 words
Process for the preparation of branched thermoplastic polycarbonates, characterized in that diphenols are completely reacted with about 0.05 to about 2.0 mol %, relative to mols of diphenols, of cyanuric chloride in a primary reaction, while controlling the pH and temperature and in the presence of a water miscible co-solvent, and thereafter the products are subjected to polycondensation, in accordance with known methods of the phase boundary process, to give high-molecular weight, branched polycarbonates.
Claim 2
Dependent Claim 74 words
Process for the preparation of branched thermoplastic polycarbonates, characterized in that diphenols are completely reacted with about 0.05 to about 2.0 mol %, relative to mols of diphenols, of cyanuric chloride in a primary reaction, while controlling the pH and temperature and in the presence of a water miscible co-solvent, and thereafter the products are subjected to polycondensation, in accordance with known methods of the phase boundary process, to give high-molecular weight, branched polycarbonates.
Claim 3
Dependent Claim 58 words
A process for the preparation of branched thermoplastic polycarbonates comprising (a) completely reacting (1) about 0.5 to about 2.0 mol % of cyanuric chloride, dissolved in a water-miscible solvent, with (2) a mixture of a diphenol and a base in water and (b) subjecting the product obtained from (a) to polycondensation in accordance with the phase boundary process.
Claim 4
Dependent Claim 58 words
A process for the preparation of branched thermoplastic polycarbonates comprising (a) completely reacting (1) about 0.5 to about 2.0 mol % of cyanuric chloride, dissolved in a water-miscible solvent, with (2) a mixture of a diphenol and a base in water and (b) subjecting the product obtained from (a) to polycondensation in accordance with the phase boundary process.
Claim 5
Dependent Claim 23 words
The process of claim 2, wherein the cyanuric chloride is dissolved in a solvent selected from the group consisting of acetone and acetonitrile.
Claim 6
Dependent Claim 19 words
The process of claim 2, wherein the diphenols contain from about 5 to about 10 mol % of halogen.
Claim 7
Dependent Claim 12 words
The process of claim 4, wherein the halogenated diphenol is tetrabromobisphenol A.
Claim 8
Dependent Claim 41 words
The process of claim 2, further comprising the addition of about 0.001 to about 0.5% by weight, relative to the weight of the branched polycarbonate, of an alkali metal salt of an inorganic mineral acid and/or organic carboxylic or sulphonic acid.
Claim 9
Dependent Claim 25 words
The process of claim 2, wherein the base of the diphenol-base mixture is present in an amount of about 25 to about 200 mol %.
Claim 10
Dependent Claim 10 words
The process of claim 7, wherein the base is NaOH.
Claim 11
Dependent Claim 55 words
In the process of synthesizing branched thermoplastic polycarbonates by way of the phase boundary method using cyanuric chloride as the trifunctional branching agent, the improvement comprising reacting between about 0.05 and 2.0 mol %, based on the mols of diphenol, of cyanuric chloride, dissolved in a water-miscible solvent, with the diphenols in a primary reaction.
Claim 12
Dependent Claim 55 words
In the process of synthesizing branched thermoplastic polycarbonates by way of the phase boundary method using cyanuric chloride as the trifunctional branching agent, the improvement comprising reacting between about 0.05 and 2.0 mol %, based on the mols of diphenol, of cyanuric chloride, dissolved in a water-miscible solvent, with the diphenols in a primary reaction.
Claim 13
Dependent Claim 82 words
A process for the preparation of branched thermoplastic polycarbonates comprising (a) completely reacting in the same reaction vessel over a period of about 1 to about 24 hours at temperatures of about 0° to about 90° C. (1) about 0.5 to about 2.0 mol % of cyanuric chloride, dissolved in a water-miscible solvent, with (2) a mixture of a diphenol and a base in water, and (b) subjecting the products obtained from (a) to polycondensation in accordance with the phase boundary process.
Claim 14
Dependent Claim 82 words
A process for the preparation of branched thermoplastic polycarbonates comprising (a) completely reacting in the same reaction vessel over a period of about 1 to about 24 hours at temperatures of about 0° to about 90° C. (1) about 0.5 to about 2.0 mol % of cyanuric chloride, dissolved in a water-miscible solvent, with (2) a mixture of a diphenol and a base in water, and (b) subjecting the products obtained from (a) to polycondensation in accordance with the phase boundary process.
Claim 15
Dependent Claim 16 words
The process of claim 10, wherein the cyanuric chloride is slowly metered into the diphenol-base mixture.
Claim 16
Dependent Claim 10 words
The process of claim 10, wherein the temperature is constant.
Claim 17
Dependent Claim 11 words
The process of claim 10, wherein the temperature is slowly increased.
Claim 18
Dependent Claim 28 words
The process of claim 10, wherein the reaction takes place over a period of about 1 to about 5 hours at temperatures between about 20° and 50° C.
Claim 19
Dependent Claim 21 words
The process of claim 10, wherein polycondensation occurs in the presence of about 0.1--to about 8 mol % of a chain-stopper.

References Cited (Backward Citations)

US3541049A Cited
US4001183A Cited
US4104245A Cited
US4059565A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-11-12 1983-05-14 1983-11-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-11-12 1987-05-14 1987-11-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-11-12 1991-05-14 1991-11-13 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag