US4698450A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyethylene wax
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1985-01-15
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Granted: 1987-10-06
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Expires: 2005-01-15
Abstract
Abstract Synthetic polyethylene wax having low molecular weight of 250 to 3000 and a density of 0.930 to 0.950 is prepared in a high pressure process at pressures of at least 800 bar using a carbonyl compound such as acetaldehyde as chain transfer agent. The resulting wax with incorporated CO has good compatibility in hot melt systems, and may be stripped to remove light ends, increase density and crystallinity and improve thermal stability.
Inventors
- 👤 Hugo J. C. Nuttens
- 👤 Gerard VanHaeren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:00
CPC Classifications
C; C08; C08F; C08F10/00; C08F10/02
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
88 words
A process for the preparation of a polyethylene wax having Mn of from 250 to 3000 and a density of 0.930 to 0.950, comprising polymerizing ethylene at a pressure of at least 800 bar, at a temperature of from 150° to 270° C., in the substantial absence of solvent and in the presence of a carbonyl compound as chain transfer agent, forming the desired wax product, and treating the formed wax product to remove at least a part of the light end containing up to 34 carbon atoms.
Claim 2
Dependent Claim
88 words
A process for the preparation of a polyethylene wax having Mn of from 250 to 3000 and a density of 0.930 to 0.950, comprising polymerizing ethylene at a pressure of at least 800 bar, at a temperature of from 150° to 270° C., in the substantial absence of solvent and in the presence of a carbonyl compound as chain transfer agent, forming the desired wax product, and treating the formed wax product to remove at least a part of the light end containing up to 34 carbon atoms.
Claim 3
Dependent Claim
22 words
A process as claimed in claim 1, in which the pressure is at least 1200 bar and the carbonyl compound is acetaldehyde.
Claim 4
Dependent Claim
31 words
A process as claimed in claim 2, in which the amount of acetaldehyde employed is from 5 to 15 wt. % based on the weight of the feed to the reactor.
Claim 5
Dependent Claim
25 words
A process as claimed in claim 2, in which the pressure in the polymerization reactor is in the range of from 1500 to 3000 bar.
Claim 6
Dependent Claim
24 words
A process as claimed in claim 1, in which the temperature of the reactor is in the range of 150° C. to 225° C.
Claim 7
Dependent Claim
21 words
A process as claimed in claim 1, in which the residence time in the reactor is from 20 to 120 seconds.
Claim 8
Dependent Claim
24 words
A process as claimed in claim 1, in which substantially all the light end containing up to 24 carbon atoms is removed by stripping.
Claim 9
Dependent Claim
20 words
A process as claimed in claim 7, in which from 8 to 10 wt. % of the wax is removed.
Claim 10
Dependent Claim
29 words
The process of claim 1 wherein the amount of carbonyl compound present is about 5 to 15 wt. % based on the weight of the feed through the reactor.
Claim 11
Dependent Claim
108 words
A process for the preparation of a thermally stable polyethylene wax having Mn of from 250 to 3000 and a density of 0.930 to 0.950, comprising: (1) polymerizing ethylene at a pressure of at least 800 bar, at a temperature of from 150° to 270° C., in the substantial absence of solvent and in the presence of from 5 to 15 wt. % based on the weight of the feed to the reactor of a carbonyl compound as chain transfer agent to give a wax product and (2) treating the wax product to remove at least a part of the light end containing up to 34 carbon atoms.
Claim 12
Dependent Claim
108 words
A process for the preparation of a thermally stable polyethylene wax having Mn of from 250 to 3000 and a density of 0.930 to 0.950, comprising: (1) polymerizing ethylene at a pressure of at least 800 bar, at a temperature of from 150° to 270° C., in the substantial absence of solvent and in the presence of from 5 to 15 wt. % based on the weight of the feed to the reactor of a carbonyl compound as chain transfer agent to give a wax product and (2) treating the wax product to remove at least a part of the light end containing up to 34 carbon atoms.
References Cited (Backward Citations)
DE2034534A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-10-05 | 1991-04-06 | 1991-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-05 | 1995-04-06 | 1995-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-05 | 1999-04-06 | 1999-10-06 | $7700.00 | Window Closed / Lapsed |