US4957943A
Expired / Lapsed
US
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Particle-filled microporous materials
Assignee: 3M Co
•
Filing: 1988-10-14
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Granted: 1990-09-18
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Expires: 2008-10-14
Abstract
Abstract A microporous particulate-filled thermoplastic polymeric article is provided. The article can be in the form of a film, a fiber, or a tube. The article has a thermoplastic polymeric structure having a plurality of interconnected passageways to provide a network of communicating pores. The microporous structure contains discrete submicron or low micron-sized particulate filler, the particulate filler being substantially non-agglomerated.
Inventors
- 👤 Jerome W. McAllister
- 👤 Kevin E. Kinzer
- 👤 James S. Mrozinski
- 👤 Eric J. Johnson
- 👤 James F. Dyrud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:29
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/20; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08J3/205; C08J3/2053; C08J3/2056; C08J9/00; C08J9/28; C08K3/02; C08K3/08; D; D01; D01D; D01D5/00; D01D5/24; D01D5/247; C08J2201/00; C08J2201/04; C08J2201/052; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249978; Y10T428/249979
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
135 words
A method for preparing a particulate-filled microporous thermoplastic polymeric shaped article which comprises the steps of (a) dispersing submicron or micron-sized particulate filler in a liquid compatible with the thermoplastic polymer to form a colloidal suspension of the particulate filler in the liquid, the particulate filler being substantially non-agglomerated; (b) melt-blending the thermoplastic polymer with a solubilizing amount of the compatible liquid containing the dispersed particulate filler at a temperature sufficient to form a homogeneous solution; (c) forming an article from the solution; (d) cooling the shaped article at a rate and to a temperature sufficient to initiate thermodynamic, non-equilibrium phase separation; (e) further cooling the article to solidify the thermoplastic polymer; and (f) removing at least a substantial portion of the compatible liquid, said particulate filler remaining substantially entirely within the thermoplastic polymer article.
Claim 2
Independent Claim
135 words
A method for preparing a particulate-filled microporous thermoplastic polymeric shaped article which comprises the steps of (a) dispersing submicron or micron-sized particulate filler in a liquid compatible with the thermoplastic polymer to form a colloidal suspension of the particulate filler in the liquid, the particulate filler being substantially non-agglomerated; (b) melt-blending the thermoplastic polymer with a solubilizing amount of the compatible liquid containing the dispersed particulate filler at a temperature sufficient to form a homogeneous solution; (c) forming an article from the solution; (d) cooling the shaped article at a rate and to a temperature sufficient to initiate thermodynamic, non-equilibrium phase separation; (e) further cooling the article to solidify the thermoplastic polymer; and (f) removing at least a substantial portion of the compatible liquid, said particulate filler remaining substantially entirely within the thermoplastic polymer article.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said phase separation is liquid-liquid phase separation.
Claim 4
Dependent Claim
13 words
The method of claim 1 wherein said phase separation is liquid-solid phase separation.
Claim 5
Dependent Claim
10 words
The method of claim 1 further comprising orienting said article.
Claim 6
Dependent Claim
49 words
A microporous particulate-filled thermoplastic polymeric article which comprises a thermoplastic polymeric structure made by the method of claim 1 having a plurality of interconnected passageways to provide a network of communicating pores, the microporous structure containing discrete submicron or low micron-sized particulate filler, the particulate filler being substantially non-agglomerated.
Claim 7
Dependent Claim
18 words
The article of claim 5 wherein said particulate filler has a major axis no larger than 5 microns.
Claim 8
Dependent Claim
18 words
The article of claim 5 wherein said particulate filler has a major axis no larger than 3 microns.
Claim 9
Dependent Claim
18 words
The article of claim 5 wherein said particulate filler has a major axis no larger than 1 micron
Claim 10
Dependent Claim
19 words
The article of claim 5 wherein said particulate filler comprises up to about 95 weight percent of said article.
Claim 11
Dependent Claim
18 words
The article of claim 5 wherein said structure comprises void spaces encased by fibrous, lacy, or semi-continuous boundaries.
Claim 12
Dependent Claim
58 words
The article of claim 5 wherein said structure comprises a multiplicity of spaced, randomly disposed, non-uniform shaped, equiaxed particles of thermoplastic polymer, adjacent particles throughout said structure being separated from one another to provide the structure with a network of interconnected micropores and being connected to each other by a plurality of fibrils consisting of said thermoplastic polymer.
Claim 13
Dependent Claim
21 words
The article of claim 5 wherein said thermoplastic polymeric structure comprises an olefinic polymer, a condensation polymer, or an oxidation polymer.
Claim 14
Dependent Claim
24 words
The article of claim 12 wherein said olefinic polymer is high density polyethylene, low density polyethylene, polypropylene, polyvinyl-containing polymer, butadiene-containing polymer, or acrylate-containing polymer.
Claim 15
Dependent Claim
15 words
The article of claim 12 wherein said condensation polymer is polyester, polyamide, polycarbonate, or polysulfone.
Claim 16
Dependent Claim
12 words
The article of claim 12 wherein said oxidation polymer is polyphenylene oxide.
Claim 17
Dependent Claim
11 words
The article of claim 5 wherein said article is a film.
Claim 18
Dependent Claim
15 words
The article of claim 16 wherein said film is oriented in at least one direction.
Claim 19
Dependent Claim
11 words
The article of claim 5 wherein said article is a fiber.
Claim 20
Dependent Claim
10 words
The article of claim 18 wherein said fiber is oriented.
Claim 21
Dependent Claim
19 words
The article of claim 5 wherein said particulate filler is a metal, a metal oxide or a carbonaceous material.
Claim 22
Dependent Claim
17 words
The article of claim 20 wherein said metal is lead, platinum, tungsten, gold, bismuth, copper or silver.
Claim 23
Dependent Claim
20 words
The article of claim 20 wherein said metal oxide is lead oxide, iron oxide, chrome oxide, alumina, titania or silica.
Claim 24
Dependent Claim
12 words
The article of claim 20 wherein said carbonaceous material is carbon black.
Claim 25
Dependent Claim
13 words
The article of claim 5 wherein said structure has a uniform porosity therethrough.
Claim 26
Dependent Claim
13 words
The article of claim 5 wherein said structure has a gradient porosity therethrough.
Claim 27
Dependent Claim
16 words
The article of claim 5 wherein said particulate filler is substantially uniformly distributed throughout said structure.
Claim 28
Dependent Claim
20 words
The article of claim 16 wherein said article further comprises at least one layer of material laminated to said film.
Claim 29
Dependent Claim
24 words
The article of claim 27 wherein said material is a woven, knitted or nonwoven fabric, a film or an additional layer of said structure.
Claim 30
Dependent Claim
10 words
The article of claim 5 further comprising an imbibed material.
Claim 31
Dependent Claim
22 words
The article of claim 29 wherein said imbibed material is a medicament, a fragrance, an antistatic agent, a surfactant, or a pesticide.
Claim 32
Dependent Claim
49 words
A microporous particulate-filled thermoplastic polymeric filtration media comprising a thermoplastic polymeric structure made by the method of claim 1 having a plurality of interconnected passageways to provide a network of communicating pores, the microporous structure containing discrete submicron or low micron-sized particulate filler, the particulate filler being substantially non-agglomerated.
Claim 33
Dependent Claim
54 words
A protective garment comprising a microporous particulate-filled thermoplastic polymeric fabric, the fabric comprising a thermoplastic polymeric structure made by the method of claim 1 having a plurality of interconnected passageways to provide a network of communicating pores, the microporous structure containing discrete submicron or low micron-sized particulate filler, the particulate filler being substantially non-agglomerated.
Claim 34
Dependent Claim
49 words
X-ray shielding material comprising a thermoplastic polymeric structure made by the method of claim 1 having a plurality of interconnected passageways to provide a network of communicating pores, the microporous structure containing discrete submicron or low micron-sized heavy metal-containing X-ray absorbing particulate filler, the particulate filler being substantially non-agglomerated.
Claim 35
Dependent Claim
49 words
Electromagnetic shielding material comprising a thermoplastic polymeric structure made by the method of claim 1 having a plurality of interconnected passageways to provide a network of communicating pores, the microporous structure containing discrete submicron or low micron-sized heavy metal electromagnetic absorbing particulate filler, the particulate filler being substantially non-agglomerated.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-17 | 1994-03-19 | 1994-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-17 | 1998-03-19 | 1998-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-17 | 2002-03-19 | 2002-09-18 | $7700.00 | Window Closed / Lapsed |