US5142000A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for increasing polyamide molecular weight with organophosphonic acid or ester catalysts in the presence of alumina-containing titanium dioxide
Assignee: Organization World Intellectual Property
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Filing: 1991-08-28
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Granted: 1992-08-25
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Expires: 2011-08-28
Abstract
Abstract A process for increasing the molecular weight of a polyamide in the presence of alumina-containing titanium dioxide, said process comprising heating a polyamide containing terminal carboxy and amino groups, and alumina-containing titanium dioxide, in the presence of a catalytically effective quantity of at least one phosphonic acid catalyst and/or ester thereof selected from: R(CH.sub.2).sub.n PO.sub.3 R.sup.1.sub.2 (I) wherein: R is 2-pyridyl or 2-methoxyphenyl; each R 1 is independently selected from H or C 1-10 alkyl; and n is 0 or an integer of from 2-5 with the proviso that n is 0 when R is 2-methoxyphenyl.
Inventors
- 👤 Robert C. Wheland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:26
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/48
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
98 words
A process for increasing the molecular weight of a polyamide in the presence of alumina-containing titanium dioxide, said process comprising heating a polyamide containing terminal carboxy and amino groups, and alumina-containing titanium dioxide, in the presence of a catalytically effective quantity of at least one phosphonic acid catalyst, ester or mixture thereof selected from: R(CH.sub.2).sub.n PO.sub.3 R.sup.1.sub.2 ( 1) wherein: R is 2-pyridyl or 2-methoxyphenyl; each R 1 is independently selected from H or C 1-10 alkyl; and n is 0 or an integer of from 2-5 with the proviso that n is 0 when R is 2-methoxyphenyl.
Claim 2
Dependent Claim
98 words
A process for increasing the molecular weight of a polyamide in the presence of alumina-containing titanium dioxide, said process comprising heating a polyamide containing terminal carboxy and amino groups, and alumina-containing titanium dioxide, in the presence of a catalytically effective quantity of at least one phosphonic acid catalyst, ester or mixture thereof selected from: R(CH.sub.2).sub.n PO.sub.3 R.sup.1.sub.2 ( 1) wherein: R is 2-pyridyl or 2-methoxyphenyl; each R 1 is independently selected from H or C 1-10 alkyl; and n is 0 or an integer of from 2-5 with the proviso that n is 0 when R is 2-methoxyphenyl.
Claim 3
Dependent Claim
10 words
A process according to claim 1 wherein R is 2-pyridyl.
Claim 4
Dependent Claim
12 words
A process according to claim 2 wherein n is 2 or 3.
Claim 5
Dependent Claim
17 words
A process according to claim 3 wherein each R 1 is H or linear C 2-4 alkyl.
Claim 6
Dependent Claim
15 words
A process according to claim 4 wherein each R 1 is linear C 2-4 alkyl.
Claim 7
Dependent Claim
16 words
A process according to claim 5 wherein each R 1 is ethyl and n is 2.
Claim 8
Dependent Claim
16 words
A process according to claim 5 wherein each R 1 is n-butyl and n is 2.
Claim 9
Dependent Claim
16 words
A process according to claim 4 wherein each R 1 is H and n is 3.
Claim 10
Dependent Claim
20 words
A process according to claim 1 wherein R is 2-methoxyphenyl and each R 1 is H or C 1-4 alkyl.
Claim 11
Dependent Claim
14 words
A process according to claim 9 wherein each R 1 is C 1-4 alkyl.
Claim 12
Dependent Claim
12 words
A process according to claim 10 wherein each R 1 is ethyl.
Claim 13
Dependent Claim
30 words
A process according to claim 1 wherein the alumina-containing titanium dioxide is present in a concentration of up to about 5 percent by weight based on the weight of polyamide.
Claim 14
Dependent Claim
21 words
A process according to claim 12 wherein the alumina-containing titanium dioxide contains up to about 8 percent by weight of alumina.
Claim 15
Dependent Claim
21 words
A process according to claim 13 wherein the alumina-containing titanium dioxide contains up to about 2 percent by weight of alumina.
References Cited (Backward Citations)
US4912175A
Cited
US4966949A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-25 | 1996-02-24 | 1996-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-25 | 2000-02-24 | 2000-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-25 | 2004-02-24 | 2004-08-25 | $7700.00 | Window Closed / Lapsed |