US4975515A
Expired / Lapsed
US
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Polyurethanes
Assignee: Albemarle Corp
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Filing: 1989-02-21
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Granted: 1990-12-04
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Expires: 2009-02-21
Abstract
Abstract Novel polyurethanes having superior high temperature performance are prepared by reacting 3,5-di(methylthio)2,6-diaminotoluene with a toluenediisocyanate prepolymer having a free --NCO content of 0.1-20% by weight, preferably a toluenediisocyanate/polyether glycol prepolymer having a free --NCO content of 2-7% by weight. The elastomers have good dynamic properties, such as resilience, that make them attractive as tire-forming materials.
Inventors
- 👤 Christopher J. Nalepa
- 👤 James H. Simon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:58
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/74; C08G18/76; C08G18/7614; C08G18/7621; C08G18/08; C08G18/10; C08G18/28; C08G18/40; C08G18/48; C08G18/4854
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
51 words
A polyurethane which loses less than 5% of its hardness between 150° C. and 175° C. and which has been prepared by a process which consists essentially of reacting 3,5-di(methylthio)-2,6-diaminotoluene containing not more than about 5% of impurities with a toluenediisocyanate prepolymer having a free --NCO content of 0.1-20% by weight.
Claim 2
Dependent Claim
51 words
A polyurethane which loses less than 5% of its hardness between 150° C. and 175° C. and which has been prepared by a process which consists essentially of reacting 3,5-di(methylthio)-2,6-diaminotoluene containing not more than about 5% of impurities with a toluenediisocyanate prepolymer having a free --NCO content of 0.1-20% by weight.
Claim 3
Dependent Claim
17 words
The polyurethane of claim 1 wherein the prepolymer has a free --NCO content of 0.5-15% by weight.
Claim 4
Dependent Claim
17 words
The polyurethane of claim 2 wherein the prepolymer has a free --NCO content of 2-7% by weight.
Claim 5
Dependent Claim
14 words
The polyurethane of claim 1 wherein the toluenediisocyanate component of the prepolymer is toluene-2,4-diisocyanate.
Claim 6
Dependent Claim
14 words
The polyurethane of claim 1 wherein the toluenediisocyanate component of the prepolymer is toluene-2,6-diisocyanate.
Claim 7
Dependent Claim
19 words
The polyurethane of claim 1 wherein the toluenediisocyanate component of the prepolymer is a mixture of toluene-2,4-diisocyanate and toluene-2,6-diisocyanate.
Claim 8
Dependent Claim
14 words
The polyurethane of claim 1 wherein the prepolymer is a toluenediisocyanate/polyether polyol reaction product.
Claim 9
Dependent Claim
14 words
The polyurethane of claim 7 wherein the polyether polyol is a polytetramethylene ether glycol.
Claim 10
Dependent Claim
25 words
The polyurethane of claim 1 wherein the 3,5-di-(methylthio)-2,6-diaminotoluene is employed in an amount such as to provide 0.8-1.2 --NH 2 groups per free --NCO group.
Claim 11
Dependent Claim
13 words
The polyurethane of claim 9 wherein the --NH 2 /--NCO ratio is 0.95-1.05.
Claim 12
Dependent Claim
44 words
The polyurethane of claim 1 which is prepared by reacting 0.8-1.2 equivalent proportions of 3,5-di(methylthio)-2,6-diaminotoluene with one equivalent proportion of a toluenediisocyanate prepolymer having a free --NCO content of 2-7% by weight and obtained by reacting a toluenediisocyanate component with a polytetramethylene ether glycol.
Claim 13
Dependent Claim
22 words
The polyurethane of claim 11 which is prepared by reacting 0.95-1.05 equivalent proportions of 3,5-di(methylthio)-2,6-diaminotoluene with one equivalent proportion of the prepolymer.
Claim 14
Dependent Claim
78 words
A process which comprises (A) casting into a mold a reaction mixture consisting essentially of 3,5-di(methylthio)-2,6-diaminotoluene containing not more than about 5% of impurities and a toluenediisocyanate prepolymer having a free --NCO content of 0.1-20% by weight, (B) curing the reaction mixture in the mold at a temperature of about 25-150° C. to form a polyurethane which loses less than 5% of its hardness between 150° C. and 175° C., and (C) removing the polyurethane from the mold.
Claim 15
Dependent Claim
78 words
A process which comprises (A) casting into a mold a reaction mixture consisting essentially of 3,5-di(methylthio)-2,6-diaminotoluene containing not more than about 5% of impurities and a toluenediisocyanate prepolymer having a free --NCO content of 0.1-20% by weight, (B) curing the reaction mixture in the mold at a temperature of about 25-150° C. to form a polyurethane which loses less than 5% of its hardness between 150° C. and 175° C., and (C) removing the polyurethane from the mold.
Claim 16
Dependent Claim
44 words
The process of claim 13 wherein the reaction mixture comprises 0.8-1.2 equivalent proportions of 3,5-di(methyl-thio)-2,6-diaminotoluene and one equivalent proportion of a toluenediisocyanate prepolymer having a free --NCO content of 2-7% by weight and obtained by reacting a toluenediisocyanate component with a polytetramethylene ether glycol.
Claim 17
Dependent Claim
22 words
The process of claim 14 wherein the reaction mixture comprises 0.95-1.05 equivalent proportions of 3,5-di-(methylthio)-2,6-diaminotoluene and one equivalent proportion of the prepolymer.
Claim 18
Dependent Claim
12 words
The process of claim 13 wherein the mold is a tire mold.
Claim 19
Dependent Claim
54 words
A tire formed from a polyurethane which loses less than 5% of its hardness between 150° C. and 175° C. and which is prepared by a process which consists essentially of reacting 3,5-di(methylthio)-2,6-diaminotoluene containing not more than about 5% of impurities with a toluenediisocyanate prepolymer having a free --NCO content of 0.1-20% by weight.
Claim 20
Dependent Claim
54 words
A tire formed from a polyurethane which loses less than 5% of its hardness between 150° C. and 175° C. and which is prepared by a process which consists essentially of reacting 3,5-di(methylthio)-2,6-diaminotoluene containing not more than about 5% of impurities with a toluenediisocyanate prepolymer having a free --NCO content of 0.1-20% by weight.
Claim 21
Dependent Claim
44 words
The tire of claim 17 which is prepared by reacting 0.8-1.2 equivalent proportions of 3,5-di(methylthio)-2,6-diaminotoluene with one equivalent proportion of a toluenediisocyanate prepolymer having a free --NCO content of 2-7% by weight and obtained by reacting a toluenediisocyanate component with a polytetramethylene ether glycol.
Claim 22
Dependent Claim
22 words
The tire of claim 18 which is prepared by reacting 0.95-1.05 equivalent proportions of 3,5-di(methylthio)-2,6-diaminotoluene with one equivalent proportion of the prepolymer.
References Cited (Backward Citations)
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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) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |