US4919992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making microporous products and the products thereof
Assignee: North West Water Group PLC
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Filing: 1988-07-01
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Granted: 1990-04-24
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Expires: 2008-07-01
Abstract
Abstract A process of producing a structural network from a semicrystalline, melt crystallizable polyarylene ether or polyarylene thioether comprising providing a molten mixture of at least one semicrystalline polymer in the presence of a melt plasticizer for the polymer which melt contains at least some polymer entities having a crystalline form, the total polymer concentration being between 5 and 50% by weight of the mixture of polymer and melt plasticizer, and heating the mixture of polymer and melt plasticizer at a heating rate of between 1° C./hour and 1000° C./hr, preferably between 10° C./hour and 100° C./hour until the mixture is at a temperature in the range 10° C. below to 20° C. above its clearing point and cooling the mixture until it solidifies whereby an open cell structure essentially free from granular superstructure is obtained.
Inventors
- 👤 David J. Blundell
- 👤 Frederic N. Cogswell
- 👤 Peter J. Meakin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:07
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/26; B; B01; B01D; B01D71/00; B01D71/06; B01D71/52; B01D71/522; C08J9/28; D; D01; D01D; D01D5/00; D01D5/42; C08J2201/00; C08J2201/04; C08J2201/052; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24273; Y10T428/249921; Y10T428/249953; Y10T428/249978; Y10T428/249987; Y10T428/31504; Y10T428/31533
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
131 words
A process of producing an open cell structure network from a semicrystalline, melt crystallisable polyarylene ether or polyarylene thioether comprising providing a molten mixture of at least one such semicrystalline polymer in the presence of a melt plasticiser for the polymer which melt contains at least some polymer entities having a crystalline form, the total polymer concentration being between 5 and 50% by weight of the mixture of polymer and melt plasticiser and heating the mixture of polymer and melt plasticiser at a heating rate of between 1° C. and 1000° C./hour, until the mixture is at a temperature in the range 10° C. below to 20° C. above its clearing point and cooling the mixture until it solidifies, whereby an open cell structure essentially free from granular superstructure is obtained.
Claim 2
Dependent Claim
131 words
A process of producing an open cell structure network from a semicrystalline, melt crystallisable polyarylene ether or polyarylene thioether comprising providing a molten mixture of at least one such semicrystalline polymer in the presence of a melt plasticiser for the polymer which melt contains at least some polymer entities having a crystalline form, the total polymer concentration being between 5 and 50% by weight of the mixture of polymer and melt plasticiser and heating the mixture of polymer and melt plasticiser at a heating rate of between 1° C. and 1000° C./hour, until the mixture is at a temperature in the range 10° C. below to 20° C. above its clearing point and cooling the mixture until it solidifies, whereby an open cell structure essentially free from granular superstructure is obtained.
Claim 3
Dependent Claim
102 words
A process of producing an open cell structure network according to claim 1 comprising melting the semicrystalline polymer in the presence of melt plasticiser for the polymer to give a homogeneous melt of the mixture, cooling the melt until the onset of crystallisation is reached and the melt becomes cloudy, subsequently reheating the mixture of polymer and melt plasticiser at a heating rate of 1° C./hour to 1,000° C., until the mixture is at a temperature in the range 10° C. below to 20° C. above its clearing point and cooling the mixture from a temperature in this range until it solidifies.
Claim 4
Dependent Claim
33 words
A process of producing a structural network according to claim 1 wherein the subsequent reheating is conducted to a temperature in the range 5° C. below to 10° C. above the clearing point.
Claim 5
Dependent Claim
18 words
A process according to claim 1 in which the product is cast while the mixture is still fluid.
Claim 6
Dependent Claim
17 words
A process according to claim 4 in which the cast product is subjected to stretching or compression.
Claim 7
Dependent Claim
25 words
A process according to claim 5 wherein the operation is performed at a temperature above the glass transition temperature of the polymer of the product.
Claim 8
Dependent Claim
33 words
A process of producing an open cell, structural network according to claim 1 in which the melt plasticiser is substantially completely removed from the structure after the open cell structure has been formed.
Claim 9
Dependent Claim
29 words
A process according to claim 7 in which the network structure is reimpregnated with a polymer or precursor materials for forming a polymer within the pores of the network.
Claim 10
Dependent Claim
97 words
An open cell, 3-dimensionally uniform structure of a semi-crystalline polyarylene ether or polyarylene thioether having an average pore size of less than 10 microns, the product having a pore volume fraction of at least 0.5 but less than 0.95, the structure comprising thin connected entities, the entities having a sectional diameter (H) of less than 1 micron and a length L, approximating to the pore size, wherein H and L are related so that H lies in the range 0.05 L to 0.5 L, and the pores are substantially filled with a melt plasticiser for the polymer.
Claim 11
Dependent Claim
97 words
An open cell, 3-dimensionally uniform structure of a semi-crystalline polyarylene ether or polyarylene thioether having an average pore size of less than 10 microns, the product having a pore volume fraction of at least 0.5 but less than 0.95, the structure comprising thin connected entities, the entities having a sectional diameter (H) of less than 1 micron and a length L, approximating to the pore size, wherein H and L are related so that H lies in the range 0.05 L to 0.5 L, and the pores are substantially filled with a melt plasticiser for the polymer.
Claim 12
Dependent Claim
20 words
An open cell semi-crystalline polymer product according to claim 9 from which the melt plasticiser has been substantially completely removed.
Claim 13
Dependent Claim
24 words
An open cell semi-crystalline polymer product according to claim 10 in which the pores are at least partially filled with a different polymeric material.
Claim 14
Dependent Claim
29 words
An open cell structure obtained by drawing the products of claim 9 to orientate the polymer of the open cell structure and reduce the section of the connecting entities.
Claim 15
Dependent Claim
24 words
An open cell product according to claim 12 which has been drawn at a temperature above the glass transition temperature of the semi-crystalline polymer.
Claim 16
Dependent Claim
33 words
A laminated structure comprising a core of an open cell product according to claim 9 and a load bearing surface skin of fibre reinforced material on at least one surface of the core.
Claim 17
Dependent Claim
24 words
A fine particle size semi-crystalline polymer product having a mean diameter of less than 5 microns, obtained by comminuting the products of claim 9.
Claim 18
Dependent Claim
20 words
A microfibril of a semi-crystalline polymer of section less than 0.1 microns prepared by comminuting the product of claim 12.
Claim 19
Dependent Claim
69 words
A drapable, composite structure comprising an open, fibrous structure of continuous filaments, of a polyarylene ether or polyarylene thioether wherein the structure contains 10 to 50% by volume of the polymer, at least 50% of the surface area of the filaments is coated by the polymer and the integrity of the structure is maintained by the polymer being attached at a plurality of points to two or more filaments.
Claim 20
Dependent Claim
69 words
A drapable, composite structure comprising an open, fibrous structure of continuous filaments, of a polyarylene ether or polyarylene thioether wherein the structure contains 10 to 50% by volume of the polymer, at least 50% of the surface area of the filaments is coated by the polymer and the integrity of the structure is maintained by the polymer being attached at a plurality of points to two or more filaments.
Claim 21
Dependent Claim
17 words
A process according to claim 1 wherein the heating rate is between 10? C./hour and 100? C./hour.
Claim 22
Dependent Claim
16 words
A polymer product according to claim 15 having a mean diameter of less than 2 microns.
References Cited (Backward Citations)
US3892425A
Cited
US4613544A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-04-23 | 1993-10-23 | 1994-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-23 | 1997-10-23 | 1998-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-23 | 2001-10-23 | 2002-04-24 | $7700.00 | Window Closed / Lapsed |