US4631329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Moisture resistant polyurethanes derived from non-aromatic diisocyanates
Assignee: Dow Silicones Corp
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Filing: 1985-11-29
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Granted: 1986-12-23
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Expires: 2005-11-29
Abstract
Abstract The reduction in tensile strength exhibited in high humidity environments by "soft" polyurethanes prepared from aliphatic or cycloaliphatic diisocyanates can be substantially reduced if the molar ratio of diisocyanate and chain extender to isocyanate-reactive species other than said chain extender in the reaction mixtures from which said polyurethanes are prepared is at least 4.
Inventors
- 👤 Gerald A. Gornowicz
- 👤 Chi-Long Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 10:15
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/74; C08G18/75; C08G18/758; C08G18/28; C08G18/40; C08G18/61; C08G18/65; C08G18/6505
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
102 words
A method for preparing a polyurethane exhibiting a hardness of less than 90 on the Shore A durometer scale and retention of useful tensile properties at a relative humidity greater than 50%, said method comprising heating a reaction mixture comprising an aliphatic or cycloaliphatic diisocyanate, a diol or diamine chain extender and at least one polyol for a period of time sufficient to form said polyurethane, wherein the molar ratio of the combination of said diisocyanate and chain extender to all isocyanate-reactive ingredients other than said chain extender is at least 4:1, respectively, and isolating the resultant polyurethane from said reaction mixture.
Claim 2
Independent Claim
102 words
A method for preparing a polyurethane exhibiting a hardness of less than 90 on the Shore A durometer scale and retention of useful tensile properties at a relative humidity greater than 50%, said method comprising heating a reaction mixture comprising an aliphatic or cycloaliphatic diisocyanate, a diol or diamine chain extender and at least one polyol for a period of time sufficient to form said polyurethane, wherein the molar ratio of the combination of said diisocyanate and chain extender to all isocyanate-reactive ingredients other than said chain extender is at least 4:1, respectively, and isolating the resultant polyurethane from said reaction mixture.
Claim 3
Dependent Claim
15 words
A method according to claim 1 where said molar ratio is from 4:1 to 7:1.
Claim 4
Dependent Claim
13 words
A method according to claim 1 where said diisocyanate is a cycloaliphatic diisocyanate.
Claim 5
Dependent Claim
17 words
A method according to claim 1 where said chain extender contains from 2 to 6 carbon atoms.
Claim 6
Dependent Claim
32 words
A method according to claim 1 where up to 50 mole percent of the polyol is replaced by an equivalent amount of a polydiorganosiloxane having terminal groups that react with said diisocyanate.
Claim 7
Dependent Claim
15 words
A method according to claim 5 where the terminal group of said polydiorganosiloxane is ##STR2##
Claim 8
Dependent Claim
12 words
A method according to claim 6 where said polydiorganosiloxane is a polydimethylsiloxane.
Claim 9
Dependent Claim
102 words
A polyurethane comprising repeating units of the general formulae ##STR3## where R represents an alkylene or cycloalkylene radical, R' represents a hydrocarbylene radical containing from 2 to 10 carbon atoms, R" represents the residue remaining following removal of the terminal hydroxyl groups of a polyether polyol or a polyester polyol and X is --NH-- or --O--, with the proviso that the molar ratio of the combination of units represented by formulae (1) and (2) to all other repeating units in the polyurethane is at least 4:1 and the polyurethane exhibits a hardness of less than 90 on the Shore A durometer scale.
Claim 10
Dependent Claim
102 words
A polyurethane comprising repeating units of the general formulae ##STR3## where R represents an alkylene or cycloalkylene radical, R' represents a hydrocarbylene radical containing from 2 to 10 carbon atoms, R" represents the residue remaining following removal of the terminal hydroxyl groups of a polyether polyol or a polyester polyol and X is --NH-- or --O--, with the proviso that the molar ratio of the combination of units represented by formulae (1) and (2) to all other repeating units in the polyurethane is at least 4:1 and the polyurethane exhibits a hardness of less than 90 on the Shore A durometer scale.
Claim 11
Dependent Claim
12 words
A polyurethane according to claim 8 where R represents a cycloalkylene radical.
Claim 12
Dependent Claim
15 words
A polyurethane according to claim 8 where R' contains from 2 to 6 carbon atoms.
Claim 13
Dependent Claim
15 words
A polyurethane according to claim 8 where said molar ratio is from 4:1 to 7:1.
Claim 14
Dependent Claim
40 words
A polyurethane according to claim 8 wherein up to 50 mole percent of the --OR"O-- units are replaced by divalent polydiorganosiloxane units terminated by an oxygen atom or an aminoalkyl group and exhibiting a molecular weight of at least 200.
Claim 15
Dependent Claim
30 words
A polyurethane according to claim 12 where said polydiorganosiloxane units are polydimethylsiloxane units exhibiting molecular weights of from 540 to 10,000 and are terminated by units of the formula ##STR4##
Claim 16
Dependent Claim
87 words
A polyurethane prepared by heating a reaction mixture comprising an aliphatic or cycloaliphatic diisocyanate, a diol or diamine chain extender and at least one polyol for a period of time sufficient to form said polyurethane, wherein the molar ratio of the combination of said diisocyanate and chain extender to all isocyanate-reactive ingredients other than said chain extender is at least 4:1, respectively, and isolating the resultant polyurethane from said reaction mixture, where said polyurethane exhibits a hardness of less than 90 on the Shore A durometer scale.
Claim 17
Dependent Claim
87 words
A polyurethane prepared by heating a reaction mixture comprising an aliphatic or cycloaliphatic diisocyanate, a diol or diamine chain extender and at least one polyol for a period of time sufficient to form said polyurethane, wherein the molar ratio of the combination of said diisocyanate and chain extender to all isocyanate-reactive ingredients other than said chain extender is at least 4:1, respectively, and isolating the resultant polyurethane from said reaction mixture, where said polyurethane exhibits a hardness of less than 90 on the Shore A durometer scale.
Claim 18
Dependent Claim
15 words
A polyurethane according to claim 14 where said molar ratio is from 4:1 to 7:1.
Claim 19
Dependent Claim
13 words
A polyurethane according to claim 14 where said diisocyanate is a cycloaliphatic diisocyanate.
Claim 20
Dependent Claim
17 words
A polyurethane according to claim 14 where said chain extender contains from 2 to 6 carbon atoms.
Claim 21
Dependent Claim
32 words
A polyurethane according to claim 14 where at least 50 mole percent of the polyol is replaced by an equivalent amount of a polydiorganosiloxane having terminal groups that react with said diisocyanate.
Claim 22
Dependent Claim
24 words
A polyurethane according to claim 18 where said polydiorganosiloxane is an aminoalkyl endblocked polydiorganosiloxane wherein the aminoalkyl radical contains three or four carbon atoms.
Claim 23
Dependent Claim
12 words
A polyurethane according to claim 18 where said polydiorganosiloxane is a polydimethylsiloxane.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-22 | 1990-06-23 | 1990-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-22 | 1994-06-23 | 1994-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-22 | 1998-06-23 | 1998-12-23 | $7700.00 | Window Closed / Lapsed |