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US4331775A
Expired / Lapsed
US
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Stabilization of post-chlorinated vinyl chloride polymers by phosphate salts
Assignee: Goodrich Corp
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Filing: 1981-04-29
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Granted: 1982-05-25
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Expires: 2001-04-29
Abstract
Abstract The invention relates to porous post-chlorinated polyvinyl chloride resins which contain or have incorporated therein a salt of phosphoric acid resulting in a substantial improvement in the thermal stability thereof during subsequent processing. The phosphate salt is added to the porous post chlorinated polymer from an aqueous solution thereof which optionally contains a surfactant, which wets the polymer particles and allows the penetration thereof by the solution. Post chlorinated polyvinyl chloride (CPVC) is the most preferred polymer or resin.
Inventors
- 👤 Dale R. Hall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:07
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/20; C08J3/205; C08J3/2053; C08J9/00; C08J9/36; C08J9/40; C08J2327/00; C08J2327/22; C08J2327/24
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
68 words
A composition of matter comprising a particulate porous post-chlorinated vinyl chloride polymer having a density in the range of about 1.52 to about 1.61 grams/cc. at 25° C. and a chlorine content in the range of about 64% to about 70% by weight from about 5% to about 65% by volume of pore space, and having a metal salt of phosphoric acid evenly dispersed throughout each particle thereof.
Claim 2
Dependent Claim
68 words
A composition of matter comprising a particulate porous post-chlorinated vinyl chloride polymer having a density in the range of about 1.52 to about 1.61 grams/cc. at 25° C. and a chlorine content in the range of about 64% to about 70% by weight from about 5% to about 65% by volume of pore space, and having a metal salt of phosphoric acid evenly dispersed throughout each particle thereof.
Claim 3
Dependent Claim
16 words
A composition as defined in claim 1 wherein the porous resin is post-chlorinated polyvinyl chloride homopolymer.
Claim 4
Dependent Claim
17 words
A composition as defined in claim 2 wherein the salt of phosphoric acid is disodium hydrogen phosphate.
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) | 1985-05-24 | 1985-11-23 | 1986-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-24 | 1989-11-23 | 1990-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-24 | 1993-11-23 | 1994-05-25 | $7700.00 | Window Closed / Lapsed |