US3759641A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and apparatus for pre-expanding polymer particles
Assignee: Atlantic Richfield Co
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Filing: 1971-01-12
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Granted: 1973-09-18
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Expires: 1991-01-12
Abstract
Abstract An apparatus and process are provided for expanding polymeric particles to a predetermined density, which particles are subject to further expansion. Agitated particulate expandable polymer is heated in a dry atmosphere in a closed vessel, under vacuum, to a predetermined density. To achieve ultra-low density expandable prepuff, a coolant such as water is introduced into the closed vessel after the predetermined density is reached, but prior to the release of the vacuum. Following release of the vacuum, the beads are removed from the closed vessel and may be molded directly, without any aging period such as that necessary following steam pre-expansion.
Inventors
- 👤 R Immel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:00
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/34; B29C44/3461; Y; Y10; Y10S; Y10S264/00; Y10S264/09
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
164 words
Apparatus for partially expanding particulate foamable polymer particles containing an aliphatic blowing agent having a boiling point below the softening point of said polymer to a predetermined density, said particles being capable of further expansion comprising: 1. a closed vessel for the containing of particulate foamable polymer particles in a substantially dry atmosphere; 2. a volumetric feed chamber for charging a predetermined quantity of said particles to said closed vessel; 3. a ribbon-blender for agitating said particles while said particles are iN said closed vessel; 4. a jacket surrounding said vessel for heating said particles in said substantially dry atmosphere while said particles are in said closed vessel; 5. a vacuum source for subjecting said particles, in said closed vessel to a reduced pressure for a predetermined time to partially expand said particles to said predetermined density; 6. a vent for releasing said vacuum; and 7. a source of compressed air for discharging said partially expanded particulate foamable polymer particles from said closed vessel.
Claim 2
Dependent Claim
164 words
Apparatus for partially expanding particulate foamable polymer particles containing an aliphatic blowing agent having a boiling point below the softening point of said polymer to a predetermined density, said particles being capable of further expansion comprising: 1. a closed vessel for the containing of particulate foamable polymer particles in a substantially dry atmosphere; 2. a volumetric feed chamber for charging a predetermined quantity of said particles to said closed vessel; 3. a ribbon-blender for agitating said particles while said particles are iN said closed vessel; 4. a jacket surrounding said vessel for heating said particles in said substantially dry atmosphere while said particles are in said closed vessel; 5. a vacuum source for subjecting said particles, in said closed vessel to a reduced pressure for a predetermined time to partially expand said particles to said predetermined density; 6. a vent for releasing said vacuum; and 7. a source of compressed air for discharging said partially expanded particulate foamable polymer particles from said closed vessel.
Claim 3
Dependent Claim
35 words
The apparatus of claim 1 wherein said vessel has a feeder attached thereon for charging a controlled amount of water to said vessel while said particles in said closed vessel are subjected to said vacuum.
Claim 4
Dependent Claim
16 words
a volumetric feed chamber for charging a predetermined quantity of said particles to said closed vessel;
Claim 5
Dependent Claim
16 words
a volumetric feed chamber for charging a predetermined quantity of said particles to said closed vessel;
Claim 6
Dependent Claim
16 words
a volumetric feed chamber for charging a predetermined quantity of said particles to said closed vessel;
Claim 7
Dependent Claim
16 words
a volumetric feed chamber for charging a predetermined quantity of said particles to said closed vessel;
Claim 8
Dependent Claim
36 words
Apparatus for partially expanding particulate foamable polymer particles containing an aliphatic blowing agent having a boiling point below the softening point of said polymer to a predetermined density, said particles being capable of further expansion comprising:
Claim 9
Dependent Claim
36 words
Apparatus for partially expanding particulate foamable polymer particles containing an aliphatic blowing agent having a boiling point below the softening point of said polymer to a predetermined density, said particles being capable of further expansion comprising:
Claim 10
Dependent Claim
15 words
a ribbon blender for agitating said particles while said particles are in said closed vessel;
Claim 11
Dependent Claim
15 words
a ribbon blender for agitating said particles while said particles are in said closed vessel;
Claim 12
Dependent Claim
14 words
a ribbon-blender for agitating said particles while said particles are iN said closed vessel;
Claim 13
Dependent Claim
14 words
a ribbon-blender for agitating said particles while said particles are iN said closed vessel;
Claim 14
Dependent Claim
22 words
a jacket surrounding said vessel for heating said particles in said substantially dry atmosphere while said particles are in said closed vessel;
Claim 15
Dependent Claim
22 words
a jacket surrounding said vessel for heating said particles in said substantially dry atmosphere while said particles are in said closed vessel;
Claim 16
Dependent Claim
25 words
a jacket surrounding said vessel for heating said particles by conduction heating in said substantially dry atmosphere while said particles are in said closed vessel;
Claim 17
Dependent Claim
25 words
a jacket surrounding said vessel for heating said particles by conduction heating in said substantially dry atmosphere while said particles are in said closed vessel;
Claim 18
Dependent Claim
28 words
a vacuum source for subjecting said particles, in said closed vessel, to a reduced pressure for a predetermined time to partially expand said particles to said predetermined density;
Claim 19
Dependent Claim
28 words
a vacuum source for subjecting said particles, in said closed vessel, to a reduced pressure for a predetermined time to partially expand said particles to said predetermined density;
Claim 20
Dependent Claim
28 words
a vacuum source for subjecting said particles, in said closed vessel to a reduced pressure for a predetermined time to partially expand said particles to said predetermined density;
Claim 21
Dependent Claim
28 words
a vacuum source for subjecting said particles, in said closed vessel to a reduced pressure for a predetermined time to partially expand said particles to said predetermined density;
Claim 22
Dependent Claim
7 words
a vent for releasing said vacuum; and
Claim 23
Dependent Claim
7 words
a vent for releasing said vacuum; and
Claim 24
Dependent Claim
28 words
a feeder connected to the closed vessel for charging a controlled amount of coolant to said vessel while said particles in said closed vessel are subjected to vacuum;
Claim 25
Dependent Claim
28 words
a feeder connected to the closed vessel for charging a controlled amount of coolant to said vessel while said particles in said closed vessel are subjected to vacuum;
Claim 26
Dependent Claim
7 words
a vent for releasing said vacuum; and
Claim 27
Dependent Claim
7 words
a vent for releasing said vacuum; and
Claim 28
Dependent Claim
18 words
a source of compressed air for discharging said partially expanded particulate foamable polymer particles from said closed vessel.
Claim 29
Dependent Claim
18 words
a source of compressed air for discharging said partially expanded particulate foamable polymer particles from said closed vessel.
Claim 30
Dependent Claim
18 words
a source of compressed air for discharging said partially expanded particulate foamable polymer particles from said closed vessel.
Claim 31
Dependent Claim
18 words
a source of compressed air for discharging said partially expanded particulate foamable polymer particles from said closed vessel.
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) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |