Patent US3878175A successfully refreshed from Google Patents.
US3878175A
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Highly absorbent spongy polymer materials
Assignee: Plastik Devices Inc
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Filing: 1973-07-27
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Granted: 1975-04-15
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Expires: 1993-07-27
Abstract
Abstract Highly absorbent spongy polymer materials are obtained by simultaneously copolymerizing and partially cross-linking a comonomer mixture of an alkyl acrylate and a heterocyclic N-vinyl monomer containing a carbonyl functionality, and a cross-linking agent in the presence of a hydrophobic liquid diluent in which the final polymer is insoluble and which will not materially swell the final resultant polymer in the presence of a freeradical catalyst at 35* - 60* C. and in the absence of atmospheric oxygen until a slightly gelled mass is obtained, followed by continued heating in an inert atmosphere to a temperature of about 100* C. for a period of time of 1/2 - 3 hours to yield an opaque self-supporting mass. The latter mass is immersed in water and allowed to swell and the water insoluble (hydrophobic) diluent is allowed to separate or is removed from its pores by squeezing. The resulting waterswelled gel can be dried to form a non-tacky sponge and re-swelled by immersion in water repeatedly, if desired.
Inventors
- 👤 Robert Steckler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:00
CPC Classifications
C; C08; C08F; C08F220/00; C08F220/02; C08F220/10; C08F220/12; C08F218/00; C08F218/02; C08F218/04; C08F226/00; C08F226/06; Y; Y10; Y10S; Y10S521/00; Y10S521/905
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
173 words
THE PROCESS OF PREPARING A SPONGY CROSS-LINKED COPOLYMER WHICH COMPRISES HEATING A SOLUTION IN A HYDROPHOBIC LIQUID DILUENT OF A MIXTURE CONSISTING ESSENTIALLY OF FROM 30 TO 90 PERCENT BY WEIGHT OF A HETEROCYCLIC N-VINYL MONOMER CONTAINING A CARBONYL FUNCTIONALITY ADJACENT TO THE NITROGEN IN ITS HETEROCYCLIC MOIETY, 10 TO 70 PERCENT BY WEIGHT OF A COMONOMER SELECTED FROM THE CLASS OF VINYL ESTERS AND ACRYLATE ESTERS, 0 TO 30 PERCENT BY WEIGHT OF ACRYLAMIDE OR METHACRYLAMIDE, AND FROM ABOUT 0.5 TO ABOUT 12 PERCENT BY WEIGHT, BASED ON THE TOTAL WEIGHT OF THE COMONOMER MIXTURE OF SAID HETEROCYCLIC N-VINYL MONOMER AND SAID ESTER OF A POLYETHYLENE GLYCOL DIMETHACRYLATE AS CROSS-LINKING AGENT, SAID HEATING CONDUCTED IN THE ABSENCE OF ATOMOSPHERIC OXYGEN AT A TEMPERATURE TURE RANGING FROM AMBIENT TO ABOUT 60*C. FOR A PERIOD OF TIME SUFFICIENT TO YIELD A SLIGHTLY GELLED MASS, FOLLOWED BY CONTINUED HEATING IN AN INERT ATMOSPHERE TO A TEMPERATURE OF ABOUT 100*C. FOR A PERIOD OF 1 TO 3 HOURS TO YIELD AN OPAQUE SELF SUPPORTING SPONGY MASS.
Claim 2
Dependent Claim
173 words
THE PROCESS OF PREPARING A SPONGY CROSS-LINKED COPOLYMER WHICH COMPRISES HEATING A SOLUTION IN A HYDROPHOBIC LIQUID DILUENT OF A MIXTURE CONSISTING ESSENTIALLY OF FROM 30 TO 90 PERCENT BY WEIGHT OF A HETEROCYCLIC N-VINYL MONOMER CONTAINING A CARBONYL FUNCTIONALITY ADJACENT TO THE NITROGEN IN ITS HETEROCYCLIC MOIETY, 10 TO 70 PERCENT BY WEIGHT OF A COMONOMER SELECTED FROM THE CLASS OF VINYL ESTERS AND ACRYLATE ESTERS, 0 TO 30 PERCENT BY WEIGHT OF ACRYLAMIDE OR METHACRYLAMIDE, AND FROM ABOUT 0.5 TO ABOUT 12 PERCENT BY WEIGHT, BASED ON THE TOTAL WEIGHT OF THE COMONOMER MIXTURE OF SAID HETEROCYCLIC N-VINYL MONOMER AND SAID ESTER OF A POLYETHYLENE GLYCOL DIMETHACRYLATE AS CROSS-LINKING AGENT, SAID HEATING CONDUCTED IN THE ABSENCE OF ATOMOSPHERIC OXYGEN AT A TEMPERATURE TURE RANGING FROM AMBIENT TO ABOUT 60*C. FOR A PERIOD OF TIME SUFFICIENT TO YIELD A SLIGHTLY GELLED MASS, FOLLOWED BY CONTINUED HEATING IN AN INERT ATMOSPHERE TO A TEMPERATURE OF ABOUT 100*C. FOR A PERIOD OF 1 TO 3 HOURS TO YIELD AN OPAQUE SELF SUPPORTING SPONGY MASS.
Claim 3
Dependent Claim
13 words
The process according to claim 1 wherein the heterocyclic N-vinyl monomer is N-vinyl-2-pyrrolidone.
Claim 4
Dependent Claim
13 words
The process according to claim 1 wherein the heterocyclic N-vinyl monomer is N-vinyl-E-caprolactam.
Claim 5
Dependent Claim
13 words
The process according to claim 1 wherein the heterocyclic N-vinyl monomer is N-vinyl-2-piperidone.
Claim 6
Dependent Claim
13 words
The process according to claim 1 wherein the heterocyclic N-vinyl monomer is N-vinyl-3-morpholinone.
Claim 7
Dependent Claim
14 words
The process according to claim 1 wherein the heterocyclic N-vinyl monomer is N-vinyl glutarimide.
Claim 8
Dependent Claim
10 words
The product prepared in accordance with the process of claim
Claim 9
Dependent Claim
11 words
The product prepared in accordance with the process of claim 2.
Claim 10
Dependent Claim
11 words
The product prepared in accordance with the process of claim 3.
Claim 11
Dependent Claim
11 words
The product prepared in accordance with the process of claim 4.
Claim 12
Dependent Claim
11 words
The product prepared in accordance with the process of claim 5.
Claim 13
Dependent Claim
11 words
The product prepared in accordance with the process of claim 6.
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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |