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US3963656A Expired / Lapsed US ⏱️ 0.0 years remaining

Thermoplastic polyurethanes and a two-stage process for their preparation

Assignee: Bayer AG
•
Filing: 1975-01-31
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Granted: 1976-06-15
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Expires: 1995-01-31
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Abstract

Abstract Polyurethane elastomers suitable for coating textiles, leather, paper and similar substrate and a multi-stage process for their production. The polyurethane elastomers are obtained from A. a polyol with an average molecular weight between 900 and 5300, B. 4,4'-diisocyanatodiphenylmethane and C. a diol with a molecular weight below 500, characterized in that the equivalent ratio ((b)/(a)+(c)) is between 0.87 and 1 and in that (a) contains at least 40% by weight of a polyurethane of the formula ##EQU1## where R is a divalent group such as can be obtained by removing the hydroxyl groups from a diol which has a molecular weight of between 700 and 1750, and Q is a divalent aliphatic, cycloaliphatic, araliphatic or aromatic group which contains 2 to 20, and preferably, 4 to 15, carbon atoms; but Q is not ##SPC1##

Inventors

  • 👤 Ernst Meisert
  • 👤 Wilhelm Goyert

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 00:41
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/10

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 158 words
A multi-stage process for the production of polyurethane elastomers that can be worked up thermoplastically and processed as a millable gum comprising the steps of: a. reacting in a first reaction stage a polyol having a molecular weight of between 700 and 1750 with 0.2 to 0.7 equivalents, per equivalent of polyol, of an aliphatic, cycloaliphatic or aromatic polyisocyanate to produce a diolurethane having a molecular weight of between 900 and 5300, b. reacting in a second reaction stage the diolurethane of step (a) with 4,4'-diisocyanatodiphenylmethane and a diol having a molecular weight below 500 at an equivalent ratio of from 0.87 to 0.97 of 4,4'-diisocyanatodiphenylmethane to the total equivalents of diol-urethane and diol, and c. mechanically mixing about 0.2 to 2.0 weight % of lubricant and mold release waxes selected from the group consisting of fatty acid esters, fatty acid amides, oxidized polyethylenes, microcrystalline waxes and silicone oil with the elastomer or any of its precursor reactants.
Claim 2
Dependent Claim 158 words
A multi-stage process for the production of polyurethane elastomers that can be worked up thermoplastically and processed as a millable gum comprising the steps of: a. reacting in a first reaction stage a polyol having a molecular weight of between 700 and 1750 with 0.2 to 0.7 equivalents, per equivalent of polyol, of an aliphatic, cycloaliphatic or aromatic polyisocyanate to produce a diolurethane having a molecular weight of between 900 and 5300, b. reacting in a second reaction stage the diolurethane of step (a) with 4,4'-diisocyanatodiphenylmethane and a diol having a molecular weight below 500 at an equivalent ratio of from 0.87 to 0.97 of 4,4'-diisocyanatodiphenylmethane to the total equivalents of diol-urethane and diol, and c. mechanically mixing about 0.2 to 2.0 weight % of lubricant and mold release waxes selected from the group consisting of fatty acid esters, fatty acid amides, oxidized polyethylenes, microcrystalline waxes and silicone oil with the elastomer or any of its precursor reactants.
Claim 3
Dependent Claim 146 words
An intimate mechanical mixture of about 0.2 to 2.0 weight % of lubricant and mold release waxes selected from the group consisting of fatty acid esters, fatty acid amides, oxidized polyethylenes, microcrystalline waxes and silicone oil with a polyurethane elastomer which is the reaction product of a. a polyol with an average molecular weight of between 900 and 5300, b. 4,4'-diisocyanatodiphenylmethane and c. a diol with a molecular weight below 500, wherein the equivalent ratio of ##EQU4## is between 0.87 and 0.97 and (a) contains at least 40% by weight of a urethane of the formula ##EQU5## where: R represents a divalent group obtained by removal of the hydroxyl groups from a diol having a molecular weight between 700 and 1750, and Q represents a divalent aliphatic, cycloaliphatic, araliphatic or aromatic group containing 2 to 20 carbon atoms, with the proviso that Q is not ##SPC3##
Claim 4
Dependent Claim 146 words
An intimate mechanical mixture of about 0.2 to 2.0 weight % of lubricant and mold release waxes selected from the group consisting of fatty acid esters, fatty acid amides, oxidized polyethylenes, microcrystalline waxes and silicone oil with a polyurethane elastomer which is the reaction product of a. a polyol with an average molecular weight of between 900 and 5300, b. 4,4'-diisocyanatodiphenylmethane and c. a diol with a molecular weight below 500, wherein the equivalent ratio of ##EQU4## is between 0.87 and 0.97 and (a) contains at least 40% by weight of a urethane of the formula ##EQU5## where: R represents a divalent group obtained by removal of the hydroxyl groups from a diol having a molecular weight between 700 and 1750, and Q represents a divalent aliphatic, cycloaliphatic, araliphatic or aromatic group containing 2 to 20 carbon atoms, with the proviso that Q is not ##SPC3##

References Cited (Backward Citations)

US3211701A Cited
US3726952A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-06-15 1979-12-15 1980-06-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-06-15 1983-12-15 1984-06-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-06-15 1987-12-15 1988-06-15 $7700.00 Window Closed / Lapsed

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