US3917548A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the suspension polymerization of polyvinyl chloride
Assignee: Stauffer Chemical Co
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Filing: 1970-12-14
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Granted: 1975-11-04
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Expires: 1990-12-14
Abstract
Abstract There is disclosed an improved process for the suspension polymerization of the homo- and copolymers of vinyl chloride involving the use, as a suspending agent, of methyl hydroxypropyl cellulose in combination with a polyvalent metal, anionic surfactant such as magnesium lauryl sulfate. The resulting polymers are characterized by their ability to absorb unusually high concentrations of plasticizers as well as by their excellent heat stability, desirable particle size distribution and high bulk densities.
Inventors
- 👤 Charles L Harrington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 17:48
CPC Classifications
C; C08; C08F; C08F14/00; C08F14/02; C08F14/04; C08F14/06; Y; Y10; Y10S; Y10S526/00; Y10S526/91
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
83 words
A POLYMER SELECTED FROM THE GROUP CONSISTING OF POLYVINYL CHLORIDE AND THE COPOLYMERS OF VINYL CHLORIDE WITH A MINOR PROPORATION OF AT LEAST ONE VINYL COMONOMER, SAID POLYMER HAVING THE FOLLOWING CHARACTERISTICS: A. A PLASTICIZER CAPACITY OF AT LEAST 120 PHR AS DETERMINED BY ASTM D-1755, B. A BULK DENSITY OF AT LEAST ABOUT 0.35 GM/CM3, AND, C. A PARTICLE SIZE DISTRIBUTION SUCH THAT AT LEAST ABOUT 90 TO 98%, BY WEIGHT, IS IN THE RANGE OF FROM ABOUT 50 TO 120 MICRONS.
Claim 2
Dependent Claim
83 words
A POLYMER SELECTED FROM THE GROUP CONSISTING OF POLYVINYL CHLORIDE AND THE COPOLYMERS OF VINYL CHLORIDE WITH A MINOR PROPORATION OF AT LEAST ONE VINYL COMONOMER, SAID POLYMER HAVING THE FOLLOWING CHARACTERISTICS: A. A PLASTICIZER CAPACITY OF AT LEAST 120 PHR AS DETERMINED BY ASTM D-1755, B. A BULK DENSITY OF AT LEAST ABOUT 0.35 GM/CM3, AND, C. A PARTICLE SIZE DISTRIBUTION SUCH THAT AT LEAST ABOUT 90 TO 98%, BY WEIGHT, IS IN THE RANGE OF FROM ABOUT 50 TO 120 MICRONS.
Claim 3
Dependent Claim
6 words
Polyvinyl chloride according to claim 1.
Claim 4
Dependent Claim
19 words
A copolymer of vinyl chloride and a minor proportion of at least one vinyl comonomer according to claim 1.
Claim 5
Dependent Claim
16 words
A copolymer of vinyl chloride and a minor proportion of vinyl acetate according to claim 3.
References Cited (Backward Citations)
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US2772258A
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US3042665A
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US3161623A
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US3592800A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |