US3759918A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing ethylene copolymer
Assignee: Mitsubishi Chemical Corp
•
Filing: 1971-12-03
•
Granted: 1973-09-18
•
Expires: 1991-12-03
Abstract
Abstract Ethylene copolymers having high Environmental Stress Cracking Resistance, which is especially useful for blow-molding, is prepared by copolymerizing ethylene with at least one Alpha olefin, in the presence of a catalyst system comprising:(1) chromium oxide supported on silica or silica-alumina having an average pore diameter or 150-10A and (2) pentaalkyl-siloxyalane or dihydrocarbyl aluminum hydrocarbonoxide.
Inventors
- 👤 K Yamaguchi
- 👤 M Hasuo
- 👤 I Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:58
CPC Classifications
C; C08; C08F; C08F10/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
41 words
The process of claim 1, wherein said Alpha -olefin has the formula: CH2 CH - R wherein R represents a hydrocarbon group selected from the group consisting of alkyl, aryl, aralkyl, alkaryl, and cycloalkyl group, having 1 - 18 carbon atoms.
Claim 2
Dependent Claim
33 words
The process of claim 1, wherein the supported chromium oxide component is prepared by applying a suitable chromium compound onto the support, and then calcining the mixture at 300* - 1, 200* C.
Claim 3
Dependent Claim
45 words
The process of claim 1, wherein the molar ratio of the second component to the first component of the catalyst system is 0.01 -500 : 1 based on Si in pentaalkylsiloxyalane or on Al in dihydrocarbyl aluminum hydrocarbon oxide to Cr in the first component.
Claim 4
Dependent Claim
14 words
The process of claim 1, wherein the copolymerization is conducted as a slurry copolymerization.
Claim 5
Dependent Claim
26 words
The process of claim 1, wherein the copolymerization is conducted at 20* - 250* C. under a pressure of from atmospheric pressure to 20 atm. .
Claim 6
Dependent Claim
15 words
The process of claim 1, wherein the copolymerization is conducted in the presence of hydrogen.
References Cited (Backward Citations)
US3081286A
Cited
US3629216A
Cited
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 |