# US 11,111,606 B2 · Production of micro- and nano-fibers by continuous microlayer coextrusion

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,111,606 B2
- Document ID: US11111606B2
- Status: Granted
- Kind: B2
- Application number: 16/134,581
- Filed: 2018-09-18
- Published: 2019-01-17
- Granted: 2021-09-07
- Earliest claimed: 2012-04-13
- Assignees: Case Western Reserve University
- Applicants: Case Western Reserve University
- Inventors: Eric Baer; Jia Wang; Deepak Langhe
- Web page: https://patentgrep.com/patent/US11111606B2

## CPC

- D01D 5/42: by cutting films into narrow ribbons or filaments or by fibrillation of films {or filaments}
- B29C 48/08: flexible, e.g. films
- B29C 48/154: Coating solid articles, i.e. non-hollow articles
- B29C 48/18: the components being layers
- B29C 48/307: {specially adapted for bringing together components, e.g. melts within the die}
- B32B 5/12: characterised by the relative arrangement of fibres or filaments of {different layers, e.g. the fibres or filaments being parallel or perpendicular to each other}
- B32B 27/08: of synthetic resin
- B32B 27/20: using fillers, pigments, thixotroping agents
- B32B 27/302: {comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers}
- B32B 27/34: comprising polyamides
- B32B 27/36: comprising polyesters
- D01D 5/253: with a non-circular cross section; Spinnerette packs therefor (D01D5/38 takes precedence)
- D01D 5/423: {by fibrillation of films or filaments}
- D01F 6/66: from polyethers
- D01F 8/00: Conjugated, i.e. bi- or multicomponent, artificial filaments or the like; Manufacture thereof
- D02G 3/22: Yarns or threads characterised by constructional features {, e.g. blending, filament/fibre (piecing of yarns or threads D01H15/00)}
- B29C 48/12: Articles with an irregular circumference when viewed in cross-section, e.g. window profiles
- B32B 2250/02: 2 layers
- B32B 2250/03: 3 layers
- B32B 2250/24: All layers being polymeric
- B32B 2250/40: Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA
- B32B 2262/02: Synthetic macromolecular fibres
- B32B 2262/0276: Polyester fibres
- B32B 2307/514: Oriented
- B32B 2307/54: Yield strength; Tensile strength
- B32B 2367/00: Polyesters, e.g. PET, i.e. polyethylene terephthalate
- B32B 2371/00: Polyethers, e.g. PEEK, i.e. polyether-etherketone; PEK, i.e. polyetherketone
- B32B 2535/00: Medical equipment, e.g. bandage, prostheses or catheter
- D10B 2331/06: polyethers
- D10B 2509/00: Medical; Hygiene
- Y10T 428/24752: Laterally noncoextensive components
- Y10T 428/2973: Particular cross section
- D01D: MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
- B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00)
- B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- D01F: CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D02G: CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
- D10B: INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A multilayered polymer composite film includes a first polymer material forming a polymer matrix and a second polymer material coextruded with the first polymer material. The second polymer material forms a plurality of fibers embedded within the polymer matrix. The fibers have a rectangular cross-section.

## Claims

### Claim 1

A method for producing a polymer construct comprising:
coextruding a first polymer material with a second polymer material to form a coextruded polymer film having discrete overlapping layers of polymeric material that each extend the entire length of the coextruded polymer film;
multiplying the overlapping layers by dividing the coextruded polymer film into portions and stacking the portions to form a multilayered composite film;
separating the first polymer material from the second polymer material to form a plurality of first polymer material fibers having a rectangular cross-section; and
adhering the first polymer material fibers together to form the polymer construct.

### Claim 2 (depends on 1)

The method of claim 1, wherein separating the first polymer material from the second polymer material comprises immersing the multilayered composite film in a solvent to dissolve the second polymer material.

### Claim 3 (depends on 2)

The method of claim 2, wherein the solvent comprises water, the first polymer material being water insoluble and the second polymer material being water soluble.

### Claim 4 (depends on 1)

The method of claim 1, wherein the first polymer material comprises polycaprolactone and the second polymer material comprises polyethylene oxide.

### Claim 5 (depends on 1)

The method of claim 1, wherein separating the first polymer material from the second polymer material comprises applying pressurized water to the multilayered composite film.

### Claim 6 (depends on 1)

The method of claim 1, further comprising depositing a static electric charge on the first polymer material fibers.

### Claim 7 (depends on 1)

The method of claim 1, wherein the first polymer material comprises polystyrene and the second polymer material comprises polyamide 6.

### Claim 8 (depends on 1)

The method of claim 1, wherein separating the first and second polymer materials forms a plurality of second polymer material fibers having a rectangular cross-section.

### Claim 9 (depends on 8)

The method of claim 8, wherein the first and second polymer material fibers are adhered together to form the polymer construct.

### Claim 10 (depends on 8)

The method of claim 8, further comprising depositing a static electric charge on the first and second polymer material fibers.

### Claim 11 (depends on 1)

The method of claim 1, wherein the first polymer material fibers are nano-scale fibers.

### Claim 12 (depends on 1)

The method of claim 1, further comprising axially orienting the multilayered composite film in at least one direction.

### Claim 13 (depends on 1)

The method of claim 1, wherein the first polymer material and the second polymer material are substantially immiscible.

### Claim 14 (depends on 1)

The method of claim 1, further comprising coextruding a third polymer material with the first polymer material and the second polymer material and separating the third polymer material from the first and second polymer materials to form third polymer material fibers having a rectangular cross-section.

### Claim 15 (depends on 14)

The method of claim 14, wherein the first polymer material comprises polystyrene, the second polymer material comprises polyamide 6, and the third polymer material comprises poly(ethylene terephthalate).

### Claim 16 (depends on 1)

The method of claim 1, further comprising entangling the first polymer material fibers before adhering the first polymer material fibers together to form the polymer construct.

### Claim 17 (depends on 1)

The method of claim 1, wherein the polymer construct is a tissue scaffold.

### Claim 18 (depends on 1)

The method of claim 1, wherein the polymer construct is a membrane.

### Claim 19 (depends on 18)

The method of claim 18, wherein the polymer construct is a filtration membrane.

### Claim 20 (depends on 18)

The method of claim 18, wherein the polymer construct is a desalination membrane.

### Claim 21 (depends on 18)

The method of claim 18, wherein the polymer construct is a water purification membrane.