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US4421870A
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Process for the preparation of cellular polyurethane elastomers based on 4,4'-diisocyanato-1,2-diphenylethane
Assignee: BASF SE
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Filing: 1982-09-20
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Granted: 1983-12-20
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Expires: 2002-09-20
Abstract
Abstract The invention relates to a method for the preparation of cellular polyurethane elastomers with densities of approximately 250 to 800 grams per liter by reacting 4,4'-diisocyanato-1,2-diphenylethane or a diisocyanato-1,2-diphenylethane isomer mixture with a 4,4'-diisocyanato-1,2-diphenylethane content of more than 95 percent by weight with higher molecular weight polyhydroxyl compounds and water, as well as optionally chain extenders in the presence of auxiliaries and/or additives according to the one-shot or preferably the prepolymer method in closed molds. Compared with products based on 4,4'-diisocyanatodiphenylmethane, the polyurethane elastomer molded parts have improved physical and thermal properties.
Inventors
- 👤 Herbert Stutz
- 👤 Karl H. Illers
- 👤 Herbert Haberkorn
- 👤 Walter Heckmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:45
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/74; C08G18/76; C08G18/7657; C08G18/7664; C08G18/7671; C08G2110/00; C08G2110/0008; C08G2110/0041; C08G2110/0066; C08G2110/0083; C08G2350/00; C08G2410/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
65 words
In a process for the manufacture of molded cellular polyurethane elastomers by reacting (a) an organic polyisocyanate with (b) higher molecular weight polyhydroxyl compounds and (c) water as well as possibly (d) chain extenders in the presence of (e) auxiliaries and/or additives wherein the improvement comprises using 4,4'-diisocyanato-1,2-diphenylethane or diisocyanato-1,2-diphenylethane isomer mixtures containing more than 95 percent by weight of 4,4'-diisocyanato-1,2-diphenylethane as the organic polyisocyanate.
Claim 2
Dependent Claim
65 words
In a process for the manufacture of molded cellular polyurethane elastomers by reacting (a) an organic polyisocyanate with (b) higher molecular weight polyhydroxyl compounds and (c) water as well as possibly (d) chain extenders in the presence of (e) auxiliaries and/or additives wherein the improvement comprises using 4,4'-diisocyanato-1,2-diphenylethane or diisocyanato-1,2-diphenylethane isomer mixtures containing more than 95 percent by weight of 4,4'-diisocyanato-1,2-diphenylethane as the organic polyisocyanate.
Claim 3
Dependent Claim
68 words
The process of claim 1 comprising (i) preparing initially a prepolymer with an isocyanate content of 2 to 20 percent by weight by reaction of 4,4'-diisocyanato-1,2-diphenylethane or a diisocyanato-1,2-diphenylethane isomer mixture containing at least 95 percent by weight of 4,4'-diisocyanato-1,2-diphenylethane and the higher molecular weight polyhydroxyl compounds and (ii) reacting the resultant prepolymer in a second reaction step with water or a mixture of water and chain extenders.
Claim 4
Dependent Claim
94 words
The process of claim 1 comprising (i) preparing initially a prepolymer with an isocyanate content of 2 to 20 percent by weight by reaction of 4,4'-diisocyanato-1,2-diphenylethane or a diisocyanato-1,2-diphenylethane isomer mixture containing at least 95 percent by weight of 4,4'-diisocyanato1,2-diphenylethane and a part of the higher molecular weight polyhydroxyl compound and (ii) reacting the resultant prepolymer in a second reaction stage with a mixture of the remainder of the higher molecular weight polyhydroxyl compound and water or a mixture of the remainder of the higher molecular weight polyhydroxyl compound, water and a chain extender.
Claim 5
Dependent Claim
30 words
The process of claim 1 wherein the ratio of the isocyanate groups of component (a) to Zerewitinoff active hydrogen atoms of components (b), (c) and (d) is 0.8 to 1.3.
Claim 6
Dependent Claim
29 words
The process of claim 1 wherein the amount of water used is up to 5 percent by weight relative to the overall weight of components (a), (b) and (d).
Claim 7
Dependent Claim
24 words
The process of claim 1 wherein 0 to 0.3 mole of chain extender is used per 1 mole of higher molecular weight polyhydroxyl compound.
Claim 8
Dependent Claim
25 words
The process of claim 1 wherein aliphatic diols and/or possibly substituted aromatic diamines having molecular weights of 60 to 500 are used as chain extenders.
Claim 9
Dependent Claim
19 words
The process of claim 1 wherein the cellular polyurethane elastomers have densities of 250 to 800 grams per liter.
Claim 10
Dependent Claim
19 words
The cellular polyurethane elastomer prepared by the process of claim 1, 2, 3, 4, 5, 6, 7 or 8.
References Cited (Backward Citations)
US3960788A
Cited
US3933701A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-19 | 1987-06-20 | 1987-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-19 | 1991-06-20 | 1991-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-19 | 1995-06-20 | 1995-12-20 | $7700.00 | Window Closed / Lapsed |