Claims
- 1. A method of making a multilayered microfiber, comprising the steps of:
- (a) introducing at least one water soluble polymer into a flowstream;
- (b) introducing at least one hydrolytically degradable polymer into a second flowstream; and
- (c) extruding the two flowstreams through a die having an array of side-by-side orifices to form the multilayer microfiber.
- 2. The method according to claim 1, further comprising the step (d) of forming the multilayered microfiber into a web.
- 3. The method according to claim 1, wherein the hydrolytically degradable polymer comprises poly(lactic acid), poly(ester amides), poly(glycolic acid), poly(hydroxy butyrate-co-valorate), or combinations thereof as copolymers, blends, or mixtures.
- 4. The method according to claim 1, wherein the water soluble polymer comprises poly(vinyl alcohol), poly(aspartic acid), poly(acrylic acid), poly(methacrylic acid), poly(acrylamide), poly(vinyl pyrrolidone), poly(alkylene oxide)s, complex carbohydrates, or combinations thereof as copolymers, blends or mixtures.
- 5. The method according to claim 1, wherein the multilayered microfiber comprises from about 9:1 to about 1:9 of water soluble polymer: hydrolytically degradable polymer.
- 6. The method according to claim 5, wherein step (c) forms the multilayered microfiber as a three layered microfiber having a composition of 75:25 poly(lactic acid): poly (vinyl alcohol) where poly(lactic acid) forms two outermost layers.
- 7. The method according to claim 1, wherein step (d) forms the microfiber into a non-woven web having a density of from about 10 to about 200 g/m.sup.2.
- 8. The method according to claim 1, the water soluble polymer and wherein the hydrolytically degradable polymer are selected for introduction into steps (a) and (b), respectively, in order the extrude in step (c) a multilayered microfiber selected from the group consisting of poly(hydroxy butyrate-co-valorate)/poly(vinyl alcohol)/poly(hydroxy butyrate-co-valorate) multilayered microfiber, poly(hydroxy butyrate-co-valorate)/poly(lactic acid) multilayered microfiber, and poly(esteramide)/poly(vinyl alcohol)/poly(esteramide) multilayered microfiber.
Parent Case Info
This is a continuation of application Ser. No. 08/367,026 filed Dec. 30, 1994 now U.S. Pat. No. 5,472,518.
US Referenced Citations (30)
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Continuations (1)
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Number |
Date |
Country |
Parent |
367026 |
Dec 1994 |
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