Patent US4046721A successfully refreshed from Google Patents.
US4046721A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low friability polyisocyanurate foams
Assignee: Dow Chemical Co
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Filing: 1976-07-30
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Granted: 1977-09-06
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Expires: 1996-07-30
Abstract
Abstract Covers novel urethane-modified polyisocyanurate rigid foams comprising a reaction product obtained by bringing together in the presence of a blowing agent, an aromatic polyisocyanate, an isocyanurate group formation catalyst and a polyol comprising an alkylene oxide adduct of a novolak resin containing 5-25 weight percent of free phenol or substituted phenol based on the weight of said resin. Said foams are particularly characterized by their low friability, good flammability resistance and excellent thermal stability.
Inventors
- 👤 Thomas H. Austin
- 👤 George P. Speranza
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:14
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/54; C08G18/546; C08G2110/00; C08G2110/0025; C08G2110/0041; C08G2115/00; C08G2115/02; Y; Y10; Y10S; Y10S521/00; Y10S521/902; Y10S521/903; Y10S521/906
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
74 words
A urethane-modified polyisocyanurate rigid foam comprising a reaction product obtained by bringing together in the presence of a blowing agent, an aromatic polyisocyanurate, an isocyanurate group formation catalyst and a polyol comprising the addition product of an alkylene oxide to a mixture of a novolak resin and excess phenol or phenolic derivative wherein said phenol or phenolic derivative is present in an amount of 5-25 weight percent based on the weight of said resin.
Claim 2
Dependent Claim
74 words
A urethane-modified polyisocyanurate rigid foam comprising a reaction product obtained by bringing together in the presence of a blowing agent, an aromatic polyisocyanurate, an isocyanurate group formation catalyst and a polyol comprising the addition product of an alkylene oxide to a mixture of a novolak resin and excess phenol or phenolic derivative wherein said phenol or phenolic derivative is present in an amount of 5-25 weight percent based on the weight of said resin.
Claim 3
Dependent Claim
25 words
The rigid foam of claim 1, wherein said novolak resin containing said excess phenol is prepared by reacting 1.5-3.0 moles of phenol per mole formaldehyde.
Claim 4
Dependent Claim
20 words
The rigid foam of claim 2, wherein said polyol has a hydroxyl number ranging from about 180 to about 325.
Claim 5
Dependent Claim
13 words
The rigid foam of claim 1, wherein said alkylene oxide is ethylene oxide.
Claim 6
Dependent Claim
13 words
The rigid foam of claim 1, wherein said alkylene oxide is propylene oxide.
Claim 7
Dependent Claim
18 words
The rigid foam of claim 1, wherein said alkylene oxide is a mixture of ethylene and propylene oxides.
Claim 8
Dependent Claim
78 words
A process for preparing a urethane-modified polyisocyanurate rigid foam comprising the steps of mixing and reacting in the presence of a blowing agent and an isocyanurate group formation catalyst, an aromatic polyisocyanate and a polyol comprising the addition product of an alkylene oxide to a mixture of a novolak resin and excess phenol or phenolic derivative wherein said phenol or phenolic derivative is present in an amount of 5-25 weight percent based on the weight of said resin.
Claim 9
Dependent Claim
78 words
A process for preparing a urethane-modified polyisocyanurate rigid foam comprising the steps of mixing and reacting in the presence of a blowing agent and an isocyanurate group formation catalyst, an aromatic polyisocyanate and a polyol comprising the addition product of an alkylene oxide to a mixture of a novolak resin and excess phenol or phenolic derivative wherein said phenol or phenolic derivative is present in an amount of 5-25 weight percent based on the weight of said resin.
Claim 10
Dependent Claim
24 words
The process of claim 7, wherein said novolak resin containing said excess phenol is prepared by reacting 1.5-3.0 moles of phenol per mole formaldehyde.
Claim 11
Dependent Claim
19 words
The process of claim 8, wherein said polyol has a hydroxyl number ranging from about 180 to about 325.
Claim 12
Dependent Claim
12 words
The process of claim 7, wherein said alkylene oxide is ethylene oxide.
Claim 13
Dependent Claim
12 words
The process of claim 7, wherein said alkylene oxide is propylene oxide.
Claim 14
Dependent Claim
18 words
The process of claim 7, wherein said alkylene oxide is a mixture of ethylene oxide and propylene oxides.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-05 | 1981-03-07 | 1981-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-05 | 1985-03-07 | 1985-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-05 | 1989-03-07 | 1989-09-06 | $7700.00 | Window Closed / Lapsed |