US4123584A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for reclaiming processed thermosetting plastic compounds
Assignee: Southwire Co LLC
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Filing: 1977-01-31
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Granted: 1978-10-31
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Expires: 1997-01-31
Abstract
Abstract A process for recovering solid scrap thermosetting plastic compounds such as crosslinkable polyethylene compound and the like, by immediately hot-granulating the fresh thermosetting scrap before it has time to fully cure and then reducing the granules to a fine powder. The powdered scrap compound may be reused directly or blended with virgin material, and recompounded into granules for reuse in molding or extrusion processes.
Inventors
- 👤 Lee K. Brewton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:49
CPC Classifications
C; C08; C08J; C08J11/00; C08J11/04; C08J11/06; B; B29; B29B; B29B17/00; B29B17/0005; B29K; B29K2023/00; B29K2023/04; B29K2023/06; B29K2105/00; B29K2105/24; B29K2105/26; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/62; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
115 words
A process for utilizing reclaimed thermosetting crosslinkable polyethylene recovered from an extruder, said recovered polyethylene being fully compounded to permit re-extrusion to a final product, the steps comprising: a. initially extruding said fully compounded polyethylene without adding additional crosslinking agents at a temperature generally sufficient to cause crosslinking of said polyethylene, said temperature being above about 170° F. and below about 480° F.; b. recovering the hot polyethylene; c. granulating the recovered polyethylene while still warm and before it has become substantially crosslinked; d. cooling the granulated polyethylene to arrest further crosslinking; e. grinding the cooled granules to a powder of about 30 mesh or less; and f. regranulating the powder suitable for extrusion use.
Claim 2
Dependent Claim
27 words
The process according to claim 1 wherein the granules formed in step (c) are about 1/4 inch which are ground to a powder of about 18 mesh.
Claim 3
Dependent Claim
27 words
The process according to claim 1 wherein said powder is blended with up to about 50% fully compound virgin polyethylene prior to being regranulated for extrusion use.
Claim 4
Dependent Claim
24 words
The process according to claim 3 wherein said granules formed in step (f) are introduced into an extruder and extruded onto an electrical conductor.
Claim 5
Dependent Claim
16 words
The process according to claim 3 wherein at least 25% by weight virgin polyethylene is blended.
Claim 6
Dependent Claim
10 words
An insulated electrical conductor made in accordance with claim 4.
Claim 7
Dependent Claim
10 words
An insulated electrical conductor made in accordance with claim 5.
Claim 8
Dependent Claim
63 words
A process for reclaiming once-processed thermosetting crosslinkable polyethylene comprising the steps of: a. initially processing fully compounded thermosetting crosslinkable polyethylene at a temperature greater than about 170° F. and below about 480° F.; b. granulating said processed polyethylene while still warm before it is fully crosslinked; c. powdering said granules; and d. reprocessing said powdered polyethylene without adding crosslinking agents for said polyethylene.
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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) | 1981-10-30 | 1982-05-01 | 1982-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-30 | 1986-05-01 | 1986-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-30 | 1990-05-01 | 1990-10-31 | $7700.00 | Window Closed / Lapsed |