US3870692A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective hydroperoxidation of polyolefins in an aqueous slurry
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1971-07-12
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Granted: 1975-03-11
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Expires: 1991-07-12
Abstract
Abstract Polyolefins are selectively hydroperoxidized in an aqueous slurry with an ozone-oxygen mixture at temperatures between 65* and 100* C. for a time which does not exceed one hour to introduce sufficient hydroperoxides for later graft copolymerization while minimizing formations of higher oxidation products of the polymer and limiting molecular weight degradation.
Inventors
- 👤 Tad L Patton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:20
CPC Classifications
C; C08; C08F; C08F255/00; C08F255/02; C08F255/023; C08F8/00; C08F8/06
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
110 words
A process for selective hydroperoxidation of finely divided solid polypropylene particles, which consists essentially of: contacting a cationic surfactant-free, slurry of said polypropylene, having a particle size of about 30 to 1,000 microns in water with a 50 to 90 mg. of ozone per liter of air mixture as the sole free radical initiator, at a temperature within the range of from 75* C. to 95* C., and for a time sufficient to obtain a hydroperoxide concentration in said polypropylene between 0.014 and 0.050 weight percent, whereby formation of higher oxidation products than hydroperoxides is significantly less than said formation at temperatures outside said 75* C. to 95* C. range.
Claim 2
Dependent Claim
110 words
A process for selective hydroperoxidation of finely divided solid polypropylene particles, which consists essentially of: contacting a cationic surfactant-free, slurry of said polypropylene, having a particle size of about 30 to 1,000 microns in water with a 50 to 90 mg. of ozone per liter of air mixture as the sole free radical initiator, at a temperature within the range of from 75* C. to 95* C., and for a time sufficient to obtain a hydroperoxide concentration in said polypropylene between 0.014 and 0.050 weight percent, whereby formation of higher oxidation products than hydroperoxides is significantly less than said formation at temperatures outside said 75* C. to 95* C. range.
Claim 3
Dependent Claim
106 words
A PROCESS FOR SELECTIVE HYDROPEROXIDATION OF FINELY DIVIDED SOLID POLYPROPYLENE PARTICLES, WHICH CONSISTS ESSENTIALLY OF: CONTACTING A CATIONIC SURFACTANT-FREE, SLURRY OF SAID POLYPROPYLENE, HAVING A PARTICLE SIZE OF ABOUT 30 TO 1,000 MICRONS IN WATER WITH A 50 TO 90 MG. OF OZONE PER LITER OF AIR MIXTURE AS THE SOLE FREE RADICAL INITIATOR, AT A TEMPERATURE WITHIN THE RANGE OF FROM 75*C. TO 95*C., AND FOR A TIME SUFFICIENT TO OBTAIN A HYDROPEROXIDE CONCENTRATION IN SAID POLYPROPYLENE BETWEEN 0.014 AND 0.050 WEIGHT PERCENT, WHEREBY FORMATION OF HIGHER OXIDATION PRODUCTS THAN HYDROPEROXIDES IS SIGNIFICANTLY LESS THAN SAID FORMATION AT TEMPERATURES OUTSIDE SAID 75*C. TO 95*C. RANGE.
Claim 4
Dependent Claim
106 words
A PROCESS FOR SELECTIVE HYDROPEROXIDATION OF FINELY DIVIDED SOLID POLYPROPYLENE PARTICLES, WHICH CONSISTS ESSENTIALLY OF: CONTACTING A CATIONIC SURFACTANT-FREE, SLURRY OF SAID POLYPROPYLENE, HAVING A PARTICLE SIZE OF ABOUT 30 TO 1,000 MICRONS IN WATER WITH A 50 TO 90 MG. OF OZONE PER LITER OF AIR MIXTURE AS THE SOLE FREE RADICAL INITIATOR, AT A TEMPERATURE WITHIN THE RANGE OF FROM 75*C. TO 95*C., AND FOR A TIME SUFFICIENT TO OBTAIN A HYDROPEROXIDE CONCENTRATION IN SAID POLYPROPYLENE BETWEEN 0.014 AND 0.050 WEIGHT PERCENT, WHEREBY FORMATION OF HIGHER OXIDATION PRODUCTS THAN HYDROPEROXIDES IS SIGNIFICANTLY LESS THAN SAID FORMATION AT TEMPERATURES OUTSIDE SAID 75*C. TO 95*C. RANGE.
Claim 5
Dependent Claim
18 words
A process in accordance with claim 1 wherein said polypropylene has a molecular weight of at least 10,000.
Claim 6
Dependent Claim
21 words
A process in accordance with claim 1 wherein the ozone treat rate is from 18 to 225 mg O3/lb of polymer/min.
Claim 7
Dependent Claim
25 words
A process in accordance with claim 1 wherein the polyolefin is polypropylene powder having a particle size within the range from 100 to 600 microns.
Claim 8
Dependent Claim
21 words
A process in accordance with claim 1 wherein the ozone treat rate is from 25 to 55 mg O3/lb of polymer/min.
Claim 9
Dependent Claim
51 words
A process in accordance with claim 1 wherein the temperature is from 78* to 94* C., the time of oxidation is about 8 minutes, the amount of ozone reacted is about 236 to 271 mg/100 g polymer, and the ROOH concentration in the polymer is about 0.044 to 0.045 wt. %.
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) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |