US4327009A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-block additives for olefin polymers
Assignee: Dow Chemical Co
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Filing: 1980-09-29
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Granted: 1982-04-27
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Expires: 2000-09-29
Abstract
Abstract Extrusion-cast films of high molecular weight, linear, low density ethylene copolymers which inherently have high block and high cling characteristics are compounded with a minor amount of a low molecular weight organic, such as a polyglycol, before being extrusion-cast as a thin film, the low molecular weight organic serving to substantially reduce the block, but retaining high cling characteristics.
Inventors
- 👤 James A. Allen
- 👤 George W. Knight
- 👤 Morris S. Edmondson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:14
CPC Classifications
C; C08; C08L; C08L23/00; C08L23/02; C08L23/04; C08L23/08; C08L23/0807; C08L23/0815; C08K; C08K5/00; C08K5/04; C08L2314/00; C08L2314/02; C08L71/00; C08L71/02
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
101 words
A process for reducing block, but retaining high cling, of extrusion-cast films of linear, low density, ethylene copolymers which inherently exhibit high block and high cling, said process comprising incorporating into the said copolymer, prior to extrusion-casting into films, an effective amount in the range of about 0.04 to about 4 weight percent of at least one block-reducing agent comprising a liquid organic having a molecular weight in the range of about 300 to about 5000, a Saybolt viscosity of at least 100 centistokes at 25° C., a boiling point above 285° C., and extrusion-casting the mixture into a thin film.
Claim 2
Dependent Claim
101 words
A process for reducing block, but retaining high cling, of extrusion-cast films of linear, low density, ethylene copolymers which inherently exhibit high block and high cling, said process comprising incorporating into the said copolymer, prior to extrusion-casting into films, an effective amount in the range of about 0.04 to about 4 weight percent of at least one block-reducing agent comprising a liquid organic having a molecular weight in the range of about 300 to about 5000, a Saybolt viscosity of at least 100 centistokes at 25° C., a boiling point above 285° C., and extrusion-casting the mixture into a thin film.
Claim 3
Dependent Claim
72 words
The process of claim 1 wherein the linear, low density, ethylene copolymer comprises ethylene copolymerized with a sufficient amount of at least one alpha, beta-ethylenically unsaturated alkene having from 3 to 12 carbon atoms to provide a copolymer having a density in the range of about 0.90 to about 0.93 gms./cc, said copolymers having a melt index in the range of about 0.2 to about 20 gms./10 min. as measured by ASTM-D-1238(E).
Claim 4
Dependent Claim
34 words
The process of claim 2 wherein the alkene is at least one selected from the group consisting of propylene, butene, isobutene, pentene, isopentene, hexene, isohexene, heptene, isoheptene, octene, isooctene, nonene, isononene, decene, and isodecene.
Claim 5
Dependent Claim
10 words
The process of claim 3 wherein the alkene is octene.
Claim 6
Dependent Claim
22 words
The process of claim 1 wherein the liquid organic has a molecular weight in the range of about 300 to about 3000.
Claim 7
Dependent Claim
37 words
The process of claim 1 wherein the liquid organic is at least one selected from the group consisting of polyalkylene ether polyols, polyepichlorohydrin, polyhydric alcohols, liquid esters of high molecular weight fatty acids, vegetable oils, and polyethers.
Claim 8
Dependent Claim
31 words
The process of claim 1 wherein the liquid organic is at least one selected from the group consisting of polyalkylene glycol, polyhydric alcohols, liquid esters of fatty acids, and polyoxyethylene ethers.
Claim 9
Dependent Claim
16 words
The process of claim 1 wherein the liquid organic is polyethylene glycol, glycerine, or glycerol monostearate.
Claim 10
Dependent Claim
22 words
The process of claim 8 wherein the liquid organic is polyethylene glycol having a molecular weight in the range of about 2000-3000.
Claim 11
Dependent Claim
36 words
The process of claim 1 wherein the extrusion-casting includes the coextrusion-casting of thin layers of low density polyethylene as outer layers of a laminar film wherein the linear, low density ethylene copolymer comprises the central layer.
References Cited (Backward Citations)
US3658980A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-04-26 | 1985-10-26 | 1986-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-04-26 | 1989-10-26 | 1990-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-04-26 | 1993-10-26 | 1994-04-27 | $7700.00 | Window Closed / Lapsed |