US4282277A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oriented, semi-crystalline polymer product and method and apparatus for producing such product
Assignee: Alcoa Corp
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Filing: 1979-09-05
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Granted: 1981-08-04
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Expires: 1999-09-05
Abstract
Abstract A thick-walled, seamless, rigid conduit having a substantially uniform wall thickness which is not less than about 0.5 percent of the outside diameter consisting essentially of an oriented crystalline thermoplastic polymer characterized by a structure comprised of radially compressed discrete, platelet-like spherulitic crystalline aggregates and having a combination of good ultimate tensile strength and low temperature tensile impact strength is described. The conduit is fabricated by solid state hydrostatic extrusion of a substantially non-oriented semi-crystalline thermoplastic polymer preform which may contain up to about 60 weight percent filler. The polymer is substantially simultaneously elongated in both circumferential and axial directions by compressive forces with the circumferential elongation being at least 100 percent. The apparatus used to produce the product is a hydrostatic extrusion press which includes an annular orifice in which the thermoplastic polymer is elongated substantially simultaneously circumferentially and axially with the circumferential elongation being at least 100 percent. Means for maintaining the rigidity of tooling and the hydrostatic extrusion fluid pressure while providing a film of the fluid on the preform for lubricity are provided in the apparatus. A sheet substantially uniform in thickness and having substantially the microstructure and properties of the conduit and excellent drawability may be made from the conduit. An article of manufacture may be made by solid state deformation processing of the conduit or the sheet.
Inventors
- 👤 Alfred R. Austen
- 👤 Darral V. Humphries
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:17
CPC Classifications
F; F16; F16L; F16L9/00; F16L9/12; B; B29; B29C; B29C31/00; B29C31/002; B29C48/00; B29C48/022; B29C48/03; B29C48/09; B29C55/00; B29C55/02; B29C55/10; B29C55/12; B29C55/16; B29C55/18; B29C55/30; C; C08; C08J; C08J5/00; C08J5/18; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2023/10; B29K2023/12; B29K2105/00; B29K2105/06; B29K2105/16; B29K2995/00; B29K2995/0037; B29K2995/0041; B29K2995/005; B29K2995/0077; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1372; Y10T428/139; Y10T428/31504; Y10T428/31725; Y10T428/31786; Y10T428/31855; Y10T428/31938; Y10T428/31942
Claims Analysis
Total Claims: 69
Claim 1
Independent Claim
230 words
A rigid conduit having a substantially uniform wall thickness which does not vary circumferentially and axially by more than plus or minus 10 percent, and which is from about 0.5 percent to about 6.25 percent of the outside diameter, the thickness being not less than 0.079 centimeter (1/32 inch) in conduits having an outside diameter of between 2.54 centimeters (1 inch) and 7.62 centimeters (3 inches), comprising at least one layer of at least one oriented semi-crystalline thermoplastic polymer characterized by a density which is at least equal to the density of the unoriented polymer and by having a microstructure substantially devoid of process induced microvoids and microfibrils and comprised of radially compressed, discrete, platelet-like spherulitic crystalline aggregates which are oriented in the plane of the conduit wall; the conduit having a circumferential tensile impact strength at -45 C. (-50 F.) which is not less than 20 percent of its circumferential tensile impact strength at 24 C. (75 F.), and having a circumferential tensile impact strength at 24 C. which is at least five times and a circumferential ultimate tensile strength which is at least one and three quarters that of a corresponding conduit of the same polymer in an unoriented state and a ratio of tensile impact strength over ultimate tensile strength which is at least 50% greater than that ratio determined for a conventional biaxially oriented thermoplastic conduit.
Claim 2
Dependent Claim
230 words
A rigid conduit having a substantially uniform wall thickness which does not vary circumferentially and axially by more than plus or minus 10 percent, and which is from about 0.5 percent to about 6.25 percent of the outside diameter, the thickness being not less than 0.079 centimeter (1/32 inch) in conduits having an outside diameter of between 2.54 centimeters (1 inch) and 7.62 centimeters (3 inches), comprising at least one layer of at least one oriented semi-crystalline thermoplastic polymer characterized by a density which is at least equal to the density of the unoriented polymer and by having a microstructure substantially devoid of process induced microvoids and microfibrils and comprised of radially compressed, discrete, platelet-like spherulitic crystalline aggregates which are oriented in the plane of the conduit wall; the conduit having a circumferential tensile impact strength at -45 C. (-50 F.) which is not less than 20 percent of its circumferential tensile impact strength at 24 C. (75 F.), and having a circumferential tensile impact strength at 24 C. which is at least five times and a circumferential ultimate tensile strength which is at least one and three quarters that of a corresponding conduit of the same polymer in an unoriented state and a ratio of tensile impact strength over ultimate tensile strength which is at least 50% greater than that ratio determined for a conventional biaxially oriented thermoplastic conduit.
Claim 3
Dependent Claim
24 words
The conduit as claimed in claim 1 in which the outside diameter is between about 5 centimeters (1.9 inches) and 63.5 centimeters (25 inches).
Claim 4
Dependent Claim
24 words
The conduit as claimed in claim 1 in which the outside diameter is between about 20 centimeters (8 inches) and 41 centimeters (16 inches).
Claim 5
Dependent Claim
28 words
The conduit as claimed in claim 1 in which the thickness of the wall is between about 0.5 to 3.0 percent of the outside diameter of the conduit.
Claim 6
Dependent Claim
28 words
The conduit as claimed in claim 1 in which the thickness of the wall is between about 1.0 to 2.0 percent of the outside diameter of the conduit.
Claim 7
Dependent Claim
21 words
The conduit as claimed in claim 1 in which the length of the conduit is at least 7.6 centimeters (3 inches).
Claim 8
Dependent Claim
25 words
The conduit as claimed in claim 2 in which the length of the conduit is between 30 centimeters (12 inches) and 244 centimeters (96 inches).
Claim 9
Dependent Claim
24 words
The conduit as claimed in claim 1 in which the thickness and concentricity of the wall does not vary by more than 5 percent.
Claim 10
Dependent Claim
27 words
The conduit as claimed in claim 1 in which the thickness and concentricity of the wall does not vary in more than plus or minus 2.5 percent.
Claim 11
Dependent Claim
15 words
The conduit as claimed in claim 1 wherein the thermoplastic polymer is a semi-crystalline polyolefin.
Claim 12
Dependent Claim
14 words
The conduit as claimed in claim 10 wherein the polyolefin is high density polyethylene.
Claim 13
Dependent Claim
13 words
The conduit as claimed in claim 1 wherein the polyolefin is isotactic polypropylene.
Claim 14
Dependent Claim
14 words
The conduit as claimed in claim 1 wherein the thermoplastic polymer is a polyamide.
Claim 15
Dependent Claim
13 words
The conduit as claimed in claim 13 wherein the polyamide is nylon 6/6.
Claim 16
Dependent Claim
13 words
The conduit as claimed in claim 13 wherein the polyamide is nylon 6/10.
Claim 17
Dependent Claim
13 words
The conduit as claimed in claim 13 wherein the polyamide is nylon 11.
Claim 18
Dependent Claim
14 words
The conduit as claimed in claim 1 wherein the thermoplastic polymer is a polyacetal.
Claim 19
Dependent Claim
14 words
The conduit as claimed in claim 1 wherein the thermoplastic polymer is a polyester.
Claim 20
Dependent Claim
13 words
The conduit as claimed in claim 18 wherein the polyester is polybutylene terephthalate.
Claim 21
Dependent Claim
19 words
The conduit of claim 1 wherein the oriented crystalline thermoplastic polymer contains at least 10 weight percent particulate filler.
Claim 22
Dependent Claim
12 words
The conduit of claim 20 wherein the thermoplastic polymer is isotactic polypropylene.
Claim 23
Dependent Claim
10 words
The conduit of claim 20 wherein the filler is talc.
Claim 24
Dependent Claim
11 words
The conduit of claim 20 wherein the filler is calcium carbonate.
Claim 25
Dependent Claim
10 words
The conduit of claim 20 wherein the filler is mica.
Claim 26
Dependent Claim
69 words
A method for producing the conduit of claim 1 which comprises compressively extruding a preform of a substantially non-oriented semi-crystalline thermoplastic polymer in a solid state with a hydrostatic fluid through an extrusion zone whereby the preform is expanded and elongated substantially simultaneously circumferentially at least 100 percent and axially at least 50 percent to form a conduit, while lubricating the surface of the polymer with the hydrostatic fluid.
Claim 27
Dependent Claim
20 words
The method as claimed in claim 25 wherein the circumferential elongation of the thermoplastic polymer is at least 200 percent.
Claim 28
Dependent Claim
18 words
The method as claimed in claim 25 wherein the axial elongation is essentially equal to the circumferential elongation.
Claim 29
Dependent Claim
46 words
The method as claimed in claim 25 in which the thermoplastic polymer is heated to a temperature which is between the 4.64 kilograms force per square centimeter heat deflection temperature of the thermoplastic polymer and 8 C. below the crystalline melt temperature of the thermoplastic polymer.
Claim 30
Dependent Claim
42 words
The method as claimed in claim 25 wherein the thermoplastic polymer is heated to a temperature which is within a temperature range of 18 C. to 30 C. (32 F. to 54 F.) below the crystalline melt temperature of the thermoplastic polymer.
Claim 31
Dependent Claim
15 words
The method as claimed in claim 25 wherein the thermoplastic polymer is a semi-crystalline polyolefin.
Claim 32
Dependent Claim
13 words
The method as claimed in claim 30 wherein the polyolefin is isotactic polypropylene.
Claim 33
Dependent Claim
17 words
The method of claim 25 in which the polymer preform is split to produce a split conduit.
Claim 34
Dependent Claim
13 words
The method of claim 25 comprising the further step of slitting the conduit.
Claim 35
Dependent Claim
24 words
The method as claimed in either claim 32 or 25 comprising the further step of heat flattening the conduit to form a sheet product.
Claim 36
Dependent Claim
191 words
A rigid sheet having a substantially uniform thickness of at least 0.079 centimeter (1/32 inch) comprising at least one layer of at least one oriented semi-crystalline thermoplastic polymer characterized by a density which is at least equal to the density of the unoriented polymer, and by having a micro-structure substantially devoid of any process induced microvoids and microfibrils and comprised of discrete, platelet-like spherulitic crystalline aggregates which are compressed in a direction transverse to the plane of the sheet and which are planar oriented; and having a tensile impact strength at 24 C. (75 F.) which is at least five times an ultimate tensile strength which is at least one and three quarters that of a corresponding sheet of the same polymer in an unoriented state when tested in the plane of the sheet and the tensile impact strength at -45 C. (-50 F.) which is not less than 20 percent of the tensile impact strength at 24 C. (75 F.) and a ratio of tensile impact strength over ultimate tensile strength which is at least 50 percent greater than the ratio determined for a conventional biaxially oriented thermoplastic polymer sheet.
Claim 37
Dependent Claim
191 words
A rigid sheet having a substantially uniform thickness of at least 0.079 centimeter (1/32 inch) comprising at least one layer of at least one oriented semi-crystalline thermoplastic polymer characterized by a density which is at least equal to the density of the unoriented polymer, and by having a micro-structure substantially devoid of any process induced microvoids and microfibrils and comprised of discrete, platelet-like spherulitic crystalline aggregates which are compressed in a direction transverse to the plane of the sheet and which are planar oriented; and having a tensile impact strength at 24 C. (75 F.) which is at least five times an ultimate tensile strength which is at least one and three quarters that of a corresponding sheet of the same polymer in an unoriented state when tested in the plane of the sheet and the tensile impact strength at -45 C. (-50 F.) which is not less than 20 percent of the tensile impact strength at 24 C. (75 F.) and a ratio of tensile impact strength over ultimate tensile strength which is at least 50 percent greater than the ratio determined for a conventional biaxially oriented thermoplastic polymer sheet.
Claim 38
Dependent Claim
15 words
The sheet as claimed in claim 35 wherein the semi-crystalline thermoplastic polymer is a polyolefin.
Claim 39
Dependent Claim
13 words
The sheet as claimed in claim 36 wherein the polyolefin is isotactic polypropylene.
Claim 40
Dependent Claim
14 words
The sheet as claimed in claim 36 wherein the polyolefin is high density polyethylene.
Claim 41
Dependent Claim
14 words
The sheet as claimed in claim 35 wherein the thermoplastic polymer is a polyamide.
Claim 42
Dependent Claim
13 words
The sheet as claimed in claim 39 wherein the polyamide is nylon 6/6.
Claim 43
Dependent Claim
13 words
The sheet as claimed in claim 39 wherein the polyamide is nylon 6/10.
Claim 44
Dependent Claim
13 words
The sheet as claimed in claim 39 wherein the polyamide is nylon 11.
Claim 45
Dependent Claim
14 words
The sheet as claimed in claim 35 wherein the thermoplastic polymer is a polyacetal.
Claim 46
Dependent Claim
14 words
The sheet as claimed in claim 35 wherein the thermoplastic polymer is a polyester.
Claim 47
Dependent Claim
14 words
The sheet as claimed in claim 35 wherein the thermoplastic polymer is polybutylene terephthalate.
Claim 48
Dependent Claim
18 words
The sheet of claim 35 wherein the oriented crystalline thermoplastic polymer contains at least 10 weight percent filler.
Claim 49
Dependent Claim
12 words
The sheet of claim 46 wherein the thermoplastic polymer is isotactic polypropylene.
Claim 50
Dependent Claim
10 words
The sheet of claim 46 wherein the filler is talc.
Claim 51
Dependent Claim
11 words
The sheet of claim 46 wherein the filler is calcium carbonate.
Claim 52
Dependent Claim
10 words
The sheet of claim 46 wherein the filler is mica.
Claim 53
Dependent Claim
191 words
An article of manufacture comprised of at least one oriented semi-crystalline thermoplastic polymer having a thickness of not less than 0.079 centimeters in at least a portion of its contour which portion is characterized by having a microstructure comprised of spherulitic crystalline aggregates compressed transversely to the plane of the portion and biaxially oriented in the plane of the portion, said portion being substantially devoid of stretch oriented microvoids and microfibrils and having a density which is at least equal to the density of the non-oriented polymer and a tensile impact strength which is at least five times and an ultimate tensile strength which is at least 11/2 times that of the corresponding substantially non-oriented thermoplastic polymer melt, a tensile impace strength at -45 C. (-50 F.) which is not less than 20 percent of its tensile impact strength at 24 C. (75 F.), a ratio of tensile impact strength to ultimate tensile strength, determined by ASTM D1822 S-type specimens, is at least 50% greater than the same ratio determined for a conventional biaxially oriented semi-crystalline thermoplastic polymer of the same composition, which polymer has the same ultimate tensile strength level.
Claim 54
Dependent Claim
191 words
An article of manufacture comprised of at least one oriented semi-crystalline thermoplastic polymer having a thickness of not less than 0.079 centimeters in at least a portion of its contour which portion is characterized by having a microstructure comprised of spherulitic crystalline aggregates compressed transversely to the plane of the portion and biaxially oriented in the plane of the portion, said portion being substantially devoid of stretch oriented microvoids and microfibrils and having a density which is at least equal to the density of the non-oriented polymer and a tensile impact strength which is at least five times and an ultimate tensile strength which is at least 11/2 times that of the corresponding substantially non-oriented thermoplastic polymer melt, a tensile impace strength at -45 C. (-50 F.) which is not less than 20 percent of its tensile impact strength at 24 C. (75 F.), a ratio of tensile impact strength to ultimate tensile strength, determined by ASTM D1822 S-type specimens, is at least 50% greater than the same ratio determined for a conventional biaxially oriented semi-crystalline thermoplastic polymer of the same composition, which polymer has the same ultimate tensile strength level.
Claim 55
Dependent Claim
14 words
The article of manufacture of claim 51 wherein the thermoplastic polymer is isotactic polypropylene.
Claim 56
Dependent Claim
17 words
The article of manufacture as claimed in claim 51 wherein the oriented semi-crystalline thermoplastic polymer is unfilled.
Claim 57
Dependent Claim
27 words
The article of manufacture as claimed in claim 51 wherein the oriented semi-crystalline thermoplastic polymer contains between at least 10 weight percent to 60 weight percent filler.
Claim 58
Dependent Claim
15 words
The article of manufacture as claimed in claim 54 in which the filler is talc.
Claim 59
Dependent Claim
16 words
The article of manufacture as claimed in claim 54 in which the filler is calcium carbonate.
Claim 60
Dependent Claim
15 words
The article of manufacture as claimed in claim 54 in which the filler is mica.
Claim 61
Dependent Claim
185 words
A crystalline biaxially oriented thermoplastic polymer product having a thickness of not less than 0.079 centimeter in at least a portion thereof, which portion is characterized by having a microstructure comprised of spherulitic crystalline aggregates compressed transversely to the plane of the portion and biaxially oriented in the plane of the portion, said portion being substantially devoid of stretch oriented microvoids and microfibrils said portion being additionally characterized by having a density at least equal to the density of the non-oriented thermoplastic polymer from which it was made and a tensile impact strength which is at least five times and an ultimate tensile strength which is at least 13/4 times that of a substantially non-oriented thermoplastic polymer of the same composition and a tensile impact strength at -45 C. (-50 F.) which is not less than 20 percent of its tensile impact strength at 24 C. (75 F.) and a ratio of tensile impact strength to ultimate strength (TIS/UTS) as determined by ASTM D1822 S-type specimens, which is at least 50 percent greater than that ratio determined for a conventional biaxially oriented crystalline thermoplastic polymer.
Claim 62
Dependent Claim
185 words
A crystalline biaxially oriented thermoplastic polymer product having a thickness of not less than 0.079 centimeter in at least a portion thereof, which portion is characterized by having a microstructure comprised of spherulitic crystalline aggregates compressed transversely to the plane of the portion and biaxially oriented in the plane of the portion, said portion being substantially devoid of stretch oriented microvoids and microfibrils said portion being additionally characterized by having a density at least equal to the density of the non-oriented thermoplastic polymer from which it was made and a tensile impact strength which is at least five times and an ultimate tensile strength which is at least 13/4 times that of a substantially non-oriented thermoplastic polymer of the same composition and a tensile impact strength at -45 C. (-50 F.) which is not less than 20 percent of its tensile impact strength at 24 C. (75 F.) and a ratio of tensile impact strength to ultimate strength (TIS/UTS) as determined by ASTM D1822 S-type specimens, which is at least 50 percent greater than that ratio determined for a conventional biaxially oriented crystalline thermoplastic polymer.
Claim 63
Dependent Claim
23 words
The product as claimed in claim 58 wherein the thermoplastic polymer contains between at least 10 weight percent and 60 weight percent filler.
Claim 64
Dependent Claim
14 words
The product as claimed in claim 59 wherein the thermoplastic polymer is semi-crystalline polypropylene.
Claim 65
Dependent Claim
13 words
The product as claimed in claim 59 wherein the filler is calcium carbonate.
Claim 66
Dependent Claim
12 words
The product as claimed in claim 59 wherein the filler is talc.
Claim 67
Dependent Claim
15 words
A product in accordance with claims 58 or 59 wherein the product is a conduit.
Claim 68
Dependent Claim
15 words
A product in accordance with claims 58 or 59 wherein the product is a sheet.
Claim 69
Dependent Claim
18 words
A product in accordance with claims 58 or 59 wherein the product is a stretch-formed product of manufacture.
References Cited (Backward Citations)
US3205290A
Cited
US3174320A
Cited
US3215590A
Cited
US3198866A
Cited
US3475245A
Cited
US3896200A
Cited
US3440130A
Cited
US3507941A
Cited
US3642976A
Cited
US3784660A
Cited
US3767757A
Cited
US3923943A
Cited
US3929959A
Cited
US4056591A
Cited
US3907961A
Cited
US4042747A
Cited
US4002709A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-08-03 | 1985-02-02 | 1985-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-03 | 1989-02-02 | 1989-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-03 | 1993-02-02 | 1993-08-04 | $7700.00 | Window Closed / Lapsed |