US3692876A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilized formaldehyde polymers
Assignee: Societa Italiana Resine SpA SIR
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Filing: 1971-02-24
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Granted: 1972-09-19
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Expires: 1991-02-24
Abstract
Abstract Formaldehyde polymers and copolymers are stabilized by incorporating 0.05 to 10 percent by weight of a complex obtained in the form of a precipitate by contacting, in a solvent or solvent mixture, an antioxidant of the phenolic type which has an acidic character and polyvinyl pyrrolidone. A composition of matter comprising said formaldehyde and said stabilizer is also claimed.
Inventors
- 👤 Jacob Ackermann
- 👤 Pierino Radici
- 👤 Franco Ferre
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:10
CPC Classifications
C; C08; C08L; C08L59/00; C08L59/02; C08L79/00
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
14 words
The stabilized formaldehyde polymers and formaldehyde copolymers prepared by the method of claim 1.
Claim 2
Dependent Claim
21 words
The composition of claim 2 wherein said stabilized formaldehyde polymer has a molecular weight of from about 10,000 to about 200,000.
Claim 3
Dependent Claim
28 words
The composition of claim 2 wherein said formaldehyde polymer contains terminal groups stabilized by a member selected from the group consisting of an ester, ether or urethane group.
Claim 4
Dependent Claim
29 words
The composition of claim 2 wherein said stabilized formaldehyde polymer composition contains less than one percent by weight of said complex of free polyvinyl pyrrolidone and free phenolic compound.
Claim 5
Dependent Claim
31 words
The method of claim 1 wherein said complex has the formula ABn, wherein A is said phenolic antioxidant and B is said polyvinyl pyrrolidone, further wherein n is 0.5 to 2.0.
Claim 6
Dependent Claim
29 words
The method of claim 1 wherein said member from said group consisting of formaldehyde polymers and formaldehyde copolymers has a molecular weight of from about 10,000 to about 200,000.
Claim 7
Dependent Claim
38 words
The method of claim 1 wherein said member selected from the group consisting of formaldehyde polymers and formaldehyde copolymers contains terminal groups stabilized by a member selected from the group consisting of an ester, ether or urethane group.
Claim 8
Dependent Claim
31 words
The method of claim 1 wherein said common solvent is selected from the group consisting of alcohol and alcohol/ketone mixtures, comprising no more than 60 percent by volume of said ketone.
Claim 9
Dependent Claim
10 words
The method of claim 1 wherein said nonsolvent is water.
Claim 10
Dependent Claim
17 words
The method of claim 1 wherein said dissolving is at a temperature of 20* to 80* C.
Claim 11
Dependent Claim
17 words
The method of claim 1 wherein said precipitating is at a temperature of 20* to 60* C.
Claim 12
Dependent Claim
28 words
The method of claim 1 wherein said dissolving yields a system comprising from 1 to 15 grams of polyvinyl pyrrolidone plus phenolic antioxidant per 100 ml of solvent.
Claim 13
Dependent Claim
26 words
The method of claim 1 wherein from one to 20 parts by volume of said nonsolvent are added per 1 part by volume of said solvent.
Claim 14
Dependent Claim
28 words
The method of claim 1 wherein following said separating less than 1% of unreacted polyvinyl pyrrolidone and phenolic antioxidant are present, based on the weight of said complex.
Claim 15
Dependent Claim
47 words
The method of claim 1 wherein one of said polyvinyl pyrrolidone and said phenolic antioxidant are added to the other of said polyvinyl pyrrolidone and said phenolic antioxidant in said solvent, said other of said polyvinyl pyrrolidone and said phenolic antioxidant being present in said common solvent.
References Cited (Backward Citations)
US3219727A
Cited
US3632686A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-19 | 1976-03-20 | 1976-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-19 | 1980-03-20 | 1980-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-19 | 1984-03-20 | 1984-09-19 | $7700.00 | Window Closed / Lapsed |