US4649001A
Expired / Lapsed
US
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Process for producing polyethylene extruded foams
Assignee: JSP Corp
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Filing: 1985-04-16
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Granted: 1987-03-10
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Expires: 2005-04-16
Abstract
Abstract In a process for producing a polyethylene extruded foam, which comprises melting and kneading a composition of a polyethylene-based resin containing a foaming agent and extrusion-foaming it, a linear low-density polyethylene having a broadness of molecular weight distribution is used as the polyethylene-based resin. The linear low-density polyethylene used has a density of 0.920 to 0.940 g/cm3, a melt flow rate of 0.3 to 10 g/10 min's and a relationship Mw/Mw>/=4 between a weight average molecular weight and a number average molecular weight.
Inventors
- 👤 Hisao Nakamura
- 👤 Shoji Iwano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:23
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/12; B; B29; B29C; B29C44/00; B29C44/34; B29C44/36; B29C44/46; B29C44/50; B29C44/505; C08J9/06; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2995/00; B29K2995/0037; B29K2995/0063; C08J2323/00; C08J2323/02; C08J2323/04; C08J2323/08; Y; Y10; Y10S; Y10S264/00; Y10S264/05; Y10S264/13
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
69 words
A process for producing a polyethylene extruded foam, which comprises melting and kneading with a foaming agent, an ethylene-α-olefin copolymer having a density of 0.920 to 0.940 g/cm 3 , a melt-flow rate of 0.3 to 10 g/10 minutes and a relationship of Mw/Mn greater than or equal to 4 between a weight average molecular weight Mw and a number average molecular weight Mn, and extruding and foaming it.
Claim 2
Dependent Claim
69 words
A process for producing a polyethylene extruded foam, which comprises melting and kneading with a foaming agent, an ethylene-α-olefin copolymer having a density of 0.920 to 0.940 g/cm 3 , a melt-flow rate of 0.3 to 10 g/10 minutes and a relationship of Mw/Mn greater than or equal to 4 between a weight average molecular weight Mw and a number average molecular weight Mn, and extruding and foaming it.
Claim 3
Dependent Claim
25 words
A process for producing a polyethylene extruded foam according to claim 1, wherein a mixture of said ethylene-α-olefin copolymer with a low-density polyethylene is used.
Claim 4
Dependent Claim
37 words
A process for producing a polyethylene extruded foam according to claim 2, wherein the low density polyethylene has a density of 0.918 to 0.923 g/cm 3 and a melt flow rate of 0.1 to 1.0 g/10 min's.
Claim 5
Dependent Claim
38 words
A process for producing a polyethylene extruded foam according to claim 2, wherein the mixture of polyethylenes consists of 10 to 40% by weight of said ethylene-α-olefin copolymer and 90 to 60% by weight of a low-density polyethylene.
Claim 6
Dependent Claim
75 words
A polyethylene composition comprising a mixture of an ethylene-α-olefin copolymer having a density of 0.920 to 0.940 g/cm 3 , a melt-flow rate of 0.3 to 10 g/10 minutes and a weight average molecular weight Mw and a number average molecular weight Mn relationship of Mw/Mn greater than or equal to 4 and a low-density polyethylene having a density of 0.918 to 0.923 g/cm 3 and a melt-flow rate of 0.1 to 1.0 g/10 minutes.
Claim 7
Dependent Claim
75 words
A polyethylene composition comprising a mixture of an ethylene-α-olefin copolymer having a density of 0.920 to 0.940 g/cm 3 , a melt-flow rate of 0.3 to 10 g/10 minutes and a weight average molecular weight Mw and a number average molecular weight Mn relationship of Mw/Mn greater than or equal to 4 and a low-density polyethylene having a density of 0.918 to 0.923 g/cm 3 and a melt-flow rate of 0.1 to 1.0 g/10 minutes.
Claim 8
Dependent Claim
27 words
A polyethylene composition as in claim 5 comprising 10 to 40% by weight of the ethylene-α-olefin copolymer and 90 to 60% by weight of the low-density polyethylene.
Claim 9
Dependent Claim
45 words
A polyethylene composition as in claim 6 having an added blowing agent yielding a foaming ratio of 5 to 50 times, a tensile strength of 11 to 12 Kg/cm 2 , a thickness of 0.2 to 6 mm, and an elongation of up to 170%.
Claim 10
Dependent Claim
51 words
A polyethylene composition comprising an ethylene-α-olefin copolymer having a density of 0.920 to 0.940 g/cm 3 , a melt-flow rate of 0.3 to 10 g/10 minutes and a relationship of Mw/Mn greater than or equal to 4 between a weight average molecular weight Mw and a number average molecular weight Mn.
Claim 11
Dependent Claim
51 words
A polyethylene composition comprising an ethylene-α-olefin copolymer having a density of 0.920 to 0.940 g/cm 3 , a melt-flow rate of 0.3 to 10 g/10 minutes and a relationship of Mw/Mn greater than or equal to 4 between a weight average molecular weight Mw and a number average molecular weight Mn.
Claim 12
Dependent Claim
45 words
A polyethylene composition as in claim 8 having an added blowing agent yielding a foaming ratio of 5 to 50 times, a tensile strength of 13 to 16 Kg/cm 2 , an elongation of up to 250%, and a thickness of 0.1 to 5 mm.
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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) | 1990-03-09 | 1990-09-08 | 1991-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-09 | 1994-09-08 | 1995-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-09 | 1998-09-08 | 1999-03-10 | $7700.00 | Window Closed / Lapsed |