US3065190A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making extruded polyethylene foams which contain a styrene polymer
Assignee: Dow Chemical Co
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Filing: 1959-11-09
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Granted: 1962-11-20
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Expires: 1979-11-09
Abstract
No abstract record available.
Inventors
- 👤 Douglas S Chisholm
- 👤 Dale D Freeman
- 👤 Robert E Holzinger
- 👤 Harry H Price
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:55
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0061; C08J2323/00; C08J2323/02; C08J2323/04; C08J2323/06; C08J2425/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
178 words
A METHOD FOR MAKING EXTRUDED POLETHYLENE FOAMS OF UNIFORM FINE CELLS AND RESILIENT STRUCTURE, WHICH METHOD COMPRISES INTIMATELY INCORPORATING POLYETHYLENE AND FROM 1 TO 3 PERCENT BY WEIGHT OF A THERMOPLASTIC STYRENE POLYMER SELECTED FROM THE GROUP CONSISTING OF THE HOMOPOLYMERS AND COPPLYMERS CONSISTING OF AT LEAST TWO DISSIMILAR MONOVINYL AROMATIC HYDROCARBONS OF THE BENZENE SERIES HAVING THE VINYL RADICAL DIRECTLY ATTACHED TO A CARBON ATOM OF THE BENZENE NUCLEUS AND COPOLYMERS OF AT LEAST 70 PERCENT BY WEIGHT OF AT LEAST ONE SUCH MONOVINYL AROMATIC HYDROCARBON AND NOT MORE THAN 30 PERCENT OF ACRYLONITRILE, WITH A VOLATILE ORGANIC FOAMING AGENT HAVING A BOILING POINT AT ATMOSPHERIC PRESSURE BELOW THE MELTING POINT OF THE POLYETHYLENE AND WHICH IS A NONSOLVENT FOR THE POLYETHYLENE, UNDER SUPERATMOSPHERIC PRESSURE TO FORM A FLOWABLE GEL, BRINGING SAID GEL TO A TEMPERATURE BETWEEN 90* AND 200*C. AND ABOVE THE BOILING POINT OF THE VOLATILE ORGANIC FOAMING AGENT, AND THEREAFTER EXTRUDING SAID GEL INTO A ZONE OF SUFFICIENTLY LOWER PRESSURE TO CAUSE THE EXTRUDED MATERIAL TO EXPAND WITH RESULTANT FORMATION OF ACELLULAR POLYETHYLENE FOAM.
Claim 2
Independent Claim
178 words
A METHOD FOR MAKING EXTRUDED POLETHYLENE FOAMS OF UNIFORM FINE CELLS AND RESILIENT STRUCTURE, WHICH METHOD COMPRISES INTIMATELY INCORPORATING POLYETHYLENE AND FROM 1 TO 3 PERCENT BY WEIGHT OF A THERMOPLASTIC STYRENE POLYMER SELECTED FROM THE GROUP CONSISTING OF THE HOMOPOLYMERS AND COPPLYMERS CONSISTING OF AT LEAST TWO DISSIMILAR MONOVINYL AROMATIC HYDROCARBONS OF THE BENZENE SERIES HAVING THE VINYL RADICAL DIRECTLY ATTACHED TO A CARBON ATOM OF THE BENZENE NUCLEUS AND COPOLYMERS OF AT LEAST 70 PERCENT BY WEIGHT OF AT LEAST ONE SUCH MONOVINYL AROMATIC HYDROCARBON AND NOT MORE THAN 30 PERCENT OF ACRYLONITRILE, WITH A VOLATILE ORGANIC FOAMING AGENT HAVING A BOILING POINT AT ATMOSPHERIC PRESSURE BELOW THE MELTING POINT OF THE POLYETHYLENE AND WHICH IS A NONSOLVENT FOR THE POLYETHYLENE, UNDER SUPERATMOSPHERIC PRESSURE TO FORM A FLOWABLE GEL, BRINGING SAID GEL TO A TEMPERATURE BETWEEN 90* AND 200*C. AND ABOVE THE BOILING POINT OF THE VOLATILE ORGANIC FOAMING AGENT, AND THEREAFTER EXTRUDING SAID GEL INTO A ZONE OF SUFFICIENTLY LOWER PRESSURE TO CAUSE THE EXTRUDED MATERIAL TO EXPAND WITH RESULTANT FORMATION OF ACELLULAR POLYETHYLENE FOAM.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-11-19 | 1966-05-21 | 1966-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-11-19 | 1970-05-21 | 1970-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-11-19 | 1974-05-21 | 1974-11-20 | $7700.00 | Window Closed / Lapsed |