Polyurethane hydrogel fibers and tapes and composites with natural and other synthetic fibers or films
AssigneeUnion Carbide Corporation
InventorsRobert John Knopf, Virgil Edison Matthews, Allen Paul Jones, Jr.
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Abstract
Method for the production of water swellable, lightly crosslinked, hydrogel polymer tapes or fibers comprises extruding an isocyanato terminated prepolymer of a poly(alkyleneoxy) polyol and an organic diisocyanate into a coagulant or crosslinking bath containing water or organic polyamine as the crosslinker.
Claims46
An article of manufacture comprising a composite of (I) a tape or fiber of a water swellable, lightly crosslinked, hydrogel polymer of the isocyanato terminated prepolymer comprising the reaction product of:
- i. a poly(alkyleneoxy) polyol having an average molecular weight up to about 25,000 wherein the alkyleneoxy group contains from 2 to 4 carbon atoms, and
- ii. an organic diisocyanate, said prepolymer lightly crosslinked with an equivalent amount of a crosslinking agent of the group:
- iii. water or organic polyamine;
- wherein said poly(alkyleneoxy) polyol is a mixture of a major amount of a poly(ethyleneoxy) diol having an average molecular weight of from about 4,000 to about 25,000 and a minor amount of a higher polyol of the group poly(alkyleneoxy) triol or poly(alkyleneoxy) tetrol or aliphatic polyhydroxyl compound of the formula C.sub.n H.sub.2n.sub.+2.sub.-m (OH).sub.m wherein n has a value of 3 to 6 and m has a value of 3 to 4 or mixtures thereof, said triol or tetrol having an average molecular weight of from about 92 to 5,000 wherein the mole ratio of diol to higher polyol in said mixture is from about 6:1 to 40:1;
- wherein the equivalents ratio of isocyanato groups to hydroxyl groups is from about 1.2:1 to about 1.6:1;
- wherein the organic polyamine is a primary or secondary diamine or triamine and wherein the equivalents of reactive crosslinking groups in said crosslinking agent used in equivalent to the number of equivalents of isocyanato groups present in said prepolymer;
- in combination with (II) a natural or a different synthetic fiber or film.
A method for producing a lightly crosslinked, water swellable, hydrogel polymer tape or fiber which comprises the steps of:
- A. producing an organic solvent solution of an isocyanato terminated prepolymer comprising the reaction product of:
- i. poly(alkyleneoxy) polyol having an average molecular weight up to about 25,000, wherein the alkyleneoxy group contains from 2 to 4 carbon atoms, and ii. organic diisocyanate,
- wherein said poly(alkyleneoxy) polyol is a mixture of a major amount of a poly(ethyleneoxy) diol having an average molecular weight of from about 4,000 to about 25,000 and a minor amount of a higher polyol of the group poly(alkyleneoxy) triol or poly(alkyleneoxy) tetrol or aliphatic polyhydroxyl compound of the formula C.sub.n H.sub.2n.sub.+2.sub.-m (OH).sub.m wherein n has a value of 3 to 6 and m has a value of 3 to 4 or mixtures thereof, said triol or tetrol having an average molecular weight of from about 92 to 5,000, wherein the mole ratio of diol to higher polyol in said mixture is from about 6:1 to 40:1;
- and wherein the equivalents ratio of isocyanato groups to hydroxyl groups is from about 1.2:1 to about 1.6:1;
- B. extruding or spinning said isocyanato terminated prepolymer solution into a crosslinking bath comprising:
- i. a crosslinking agent for the isocyanato terminated prepolymer of the group (a) water or (b) organic polyamine,
- wherein said polyamine is a primary or secondary diamine or triamine and wherein the equivalents of reactive crosslinking groups in said crosslinking agent used is equivalent to the number of equivalents of isocyanato groups present in said prepolymer;
- and
- C. recovering the lightly crosslinked, water swellable, hydrogel tape or fiber.
Dependencies are inferred from the claim text.