Patent US4554293A successfully refreshed from Google Patents.
US4554293A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lightly crosslinked linear olefinic polymer foam blends and process for making
Assignee: Dow Chemical Co
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Filing: 1985-04-19
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Granted: 1985-11-19
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Expires: 2005-04-19
Abstract
Abstract An expandable blend of a linear olefinic polymer and a crosslinkable polymer for production of lightly crosslinked foamed polymers and a process for the preparation thereof is provided. The presence of a crosslinkable polymer component in the blend increases the melt strength of the linear olefinic component so that conventional melt processing techniques may be utilized to produce foamed polymers. Both open and closed cell foams may be produced.
Inventors
- 👤 Chung P. Park
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:59
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/12; C08J9/14; C08J9/143; C08J9/147; C08J9/0061; C08J9/149; C08K; C08K3/00; C08K3/34; C08K5/00; C08K5/02; C08K5/16; C08K5/17; C08K5/54; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/06; C08L23/08; C08L23/0807; C08L23/0815; C08J2323/00; C08J2323/02; C08K3/18; C08K3/20; C08K3/22; C08L2203/00; C08L2203/14; C08L2207/00; C08L2207/06; C08L2207/066; C08L23/0846; C08L23/0869; C08L2312/00; C08L2312/08; C08L63/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
105 words
A process for the preparation of a polymeric foam comprising the steps of: (a) melt processing a blend of a linear olefin polymer and a crosslinkable polymer having one or more carboxylic acid, amide, amine, or hydroxyl functional groups, together with a volatile blowing agent and a sufficient amount of a crosslinking agent selected from the group consisting of epoxy-functional silanes, amino-functional silanes, organofunctional alkoxy silanes, multiepoxyfunctional silanes, amines, and titanates, to form a flowable admixture; and (b) extruding said admixture through a die to a zone of lower pressure and activating said blowing agent to expand the polymer blend to a cellular crosslinked structure.
Claim 2
Dependent Claim
105 words
A process for the preparation of a polymeric foam comprising the steps of: (a) melt processing a blend of a linear olefin polymer and a crosslinkable polymer having one or more carboxylic acid, amide, amine, or hydroxyl functional groups, together with a volatile blowing agent and a sufficient amount of a crosslinking agent selected from the group consisting of epoxy-functional silanes, amino-functional silanes, organofunctional alkoxy silanes, multiepoxyfunctional silanes, amines, and titanates, to form a flowable admixture; and (b) extruding said admixture through a die to a zone of lower pressure and activating said blowing agent to expand the polymer blend to a cellular crosslinked structure.
Claim 3
Dependent Claim
40 words
The process of claim 1 in which said linear low density polyethylene is present in an amount of from 5 to 95% by weight and said crosslinkable polymer is present in an amount of from 95 to 5% by weight.
Claim 4
Dependent Claim
15 words
The process of claim 1 in which said crosslinkable polymer is an ethylene-acrylic acid copolymer.
Claim 5
Dependent Claim
14 words
The process of claim 2 in which said crosslinking agent is an epoxyfunctional silane.
Claim 6
Dependent Claim
34 words
The process of claim 1 in which a sufficient amount of an alcohol is added along with said blowing agent to control the degree of crosslinking of said crosslinkable polymer in the admixture formed.
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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) | 1988-11-18 | 1989-05-20 | 1989-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-18 | 1993-05-20 | 1993-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-18 | 1997-05-20 | 1997-11-19 | $7700.00 | Window Closed / Lapsed |