Patent US4254513A successfully refreshed from Google Patents.
Patent US4330664A successfully refreshed from Google Patents.
US4330664A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polycarbonate transesterification with catalyst containing aluminum hydride or borohydride group
Assignee: General Electric Co
•
Filing: 1981-04-27
•
Granted: 1982-05-18
•
Expires: 2001-04-27
Abstract
Abstract An improved aromatic polycarbonate transesterification process comprising reacting a bis(aryl)carbonate and a dihydric phenol in the presence of a transesterification catalyst, the improvement wherein the catalyst contains an aluminum hydride or borohydride group.
Inventors
- 👤 Daniel J. Brunelle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:48
CPC Classifications
C; C08; C08G; C08G64/00; C08G64/20; C08G64/30; C08G64/307
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
113 words
In a process of preparing a high molecular weight polycarbonate by reacting at least one bis(aryl)carbonate with at least one dihydric phenol in the presence of a transesterification catalyst, the improvement wherein the catalyst is (1) a borohydride having the general formula: MBH.sub.n R.sub.4-n wherein M is selected from the class consisting of an alkali metal, an alkaline earth metal, a quaternary hydrocarbon ammonium, a quaternary hydrocarbon phosphonium and a tertiary hydrocarbon sulfonium group, n is a number of from 1 to 4, and R is a hydrocarbon or hydrocarbonoxy group, or (2) an aluminum hydride having the general formula: MAlH.sub.n R.sub.4-n wherein M, n and R are the same as described above.
Claim 2
Dependent Claim
113 words
In a process of preparing a high molecular weight polycarbonate by reacting at least one bis(aryl)carbonate with at least one dihydric phenol in the presence of a transesterification catalyst, the improvement wherein the catalyst is (1) a borohydride having the general formula: MBH.sub.n R.sub.4-n wherein M is selected from the class consisting of an alkali metal, an alkaline earth metal, a quaternary hydrocarbon ammonium, a quaternary hydrocarbon phosphonium and a tertiary hydrocarbon sulfonium group, n is a number of from 1 to 4, and R is a hydrocarbon or hydrocarbonoxy group, or (2) an aluminum hydride having the general formula: MAlH.sub.n R.sub.4-n wherein M, n and R are the same as described above.
Claim 3
Dependent Claim
38 words
The claim 1 process wherein the borohydride has the structural formula [R'.sub.4 N]BH.sub.n R.sub.4-n wherein each R' is an alkyl group containing from 1 to 4 carbon atoms, and n is a number of from 1 to 4.
Claim 4
Dependent Claim
11 words
The claim 2 process wherein each R' is an n-butyl group.
Claim 5
Dependent Claim
8 words
The claim 1 process wherein n is 4.
Claim 6
Dependent Claim
8 words
The claim 1 process wherein n is 3.
Claim 7
Dependent Claim
9 words
The claim 1 process wherein the n is 2.
Claim 8
Dependent Claim
9 words
The claim 1 process wherein the n is 1.
Claim 9
Dependent Claim
39 words
In a process of preparing a high molecular weight polycarbonate by reacting bis(4-hydroxyphenyl)-propane-2,2 with diphenyl carbonate in the presence of a transesterification catalyst, the improvement wherein the catalyst is quaternary n-butyl ammonium borohydride having the formula (C.sub.4 H.sub.9).sub.4 NBH.sub.4.
Claim 10
Dependent Claim
39 words
In a process of preparing a high molecular weight polycarbonate by reacting bis(4-hydroxyphenyl)-propane-2,2 with diphenyl carbonate in the presence of a transesterification catalyst, the improvement wherein the catalyst is quaternary n-butyl ammonium borohydride having the formula (C.sub.4 H.sub.9).sub.4 NBH.sub.4.
Claim 11
Dependent Claim
37 words
In a process of preparing a high molecular weight polycarbonate by reacting bis(4-hydroxyphenyl)-propane-2,2 with diphenyl carbonate in the presence of a transesterification catalyst, the improvement wherein the catalyst is lithium aluminum hydride having the structural formula LiAlH.sub.4.
Claim 12
Dependent Claim
37 words
In a process of preparing a high molecular weight polycarbonate by reacting bis(4-hydroxyphenyl)-propane-2,2 with diphenyl carbonate in the presence of a transesterification catalyst, the improvement wherein the catalyst is lithium aluminum hydride having the structural formula LiAlH.sub.4.
Claim 13
Dependent Claim
36 words
In a process of preparing a high molecular weight polycarbonate by reacting bis(4-hydroxyphenyl)-propane-2,2 with diphenyl carbonate in the presence of a transesterification catalyst, the improvement wherein the catalyst is sodium borohydride having the structural formula NaBH.sub.4.
Claim 14
Dependent Claim
36 words
In a process of preparing a high molecular weight polycarbonate by reacting bis(4-hydroxyphenyl)-propane-2,2 with diphenyl carbonate in the presence of a transesterification catalyst, the improvement wherein the catalyst is sodium borohydride having the structural formula NaBH.sub.4.
Claim 15
Dependent Claim
39 words
In a process of preparing a high molecular weight polycarbonate by reacting bis(4-hydroxyphenyl)-propane-2,2 with diphenyl carbonate in the presence of a transesterification catalyst, the improvement wherein the catalyst is quaternary methyl ammonium borohydride having the structural formula (CH.sub.3).sub.4 NBH.sub.4.
Claim 16
Dependent Claim
39 words
In a process of preparing a high molecular weight polycarbonate by reacting bis(4-hydroxyphenyl)-propane-2,2 with diphenyl carbonate in the presence of a transesterification catalyst, the improvement wherein the catalyst is quaternary methyl ammonium borohydride having the structural formula (CH.sub.3).sub.4 NBH.sub.4.
References Cited (Backward Citations)
US3153008A
Cited
GB1079822A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-17 | 1985-11-16 | 1986-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-17 | 1989-11-16 | 1990-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-17 | 1993-11-16 | 1994-05-18 | $7700.00 | Window Closed / Lapsed |