US 4,062,834 AGranted

Method for preparing extrudable polytetramethylene ether polyurethane-urea resins

AssigneeEthicon, Inc.

InventorsDenis Keith Gilding, John Albert Taylor, Jr.

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Abstract

Melt extrudable thermoplastic polytetramethylene ether polyurethane-urea elastomers of this invention are prepared by reacting a tetramethylene ether glycol with 4,4'-diphenyl methane diisocyanate to form a polytetramethylene ether polyurethane pre-polymer having a number average molecular weight of from about 2,000 to about 10,000. This pre-polymer is water extended to form a thermoplastic bio-compatible elastomer having a number average molecular weight of about 50,000 to about 100,000, and a weight average molecular weight of about 300,000 to about 1,000,000. The elastomer so obtained has a softening point in the range of 127.degree. - 149.degree. C. and may be melt extruded without decomposition to produce articles useful in the field of medicine and surgery.

Claims11

Dependent claims

A process for preparing melt-extrudable polytetramethylene ether polyurethane-urea resins which comprises:

a. reacting a polytetramethylene ether glycol having a molecular weight of from about 650 to 2,000 with 4,4'-diphenyl methane diisocyanate to form a prepolymer having isocyanate termination and a number average molecular weight of from about 2,000 to 10,000,
b. dissolving the prepolymer in an organic solvent,
c. extending said prepolymer by reaction in said organic solvent with water to form a solution of polytetramethylene ether polyurethane-urea polymer having a molecular weight of from about 50,000 to 100,000 in said solvent,
d. precipitating said polytetramethylene ether polyurethane-urea polymer from said solvent in an aqueous monohydric alcohol solution, and
e. recovering said precipitated polymer from said aqueous solution.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application: 05/572,773Filed 29 Apr 1975 · continuation in part
Priority: 16 May 1973
Granted: 13 Dec 1977
Term ends: Not estimatedThe source records don’t support an estimate.

Classification4 codes

C08G 18/7671
Containing alkylene polyphenyl groups: containing only one alkylene bisphenyl group
C08G 18/10
Processes: prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
C08G 18/4854
Polyethers: polyethers containing oxyalkylene groups having four carbon atoms in the alkylene group
C08G
Macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds