US3912664A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of flexible and rigid materials from scrap polyvinylchloride, its copolymers and cogeners
Assignee: Horizons Inc
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Filing: 1974-08-23
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Granted: 1975-10-14
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Expires: 1994-08-23
Abstract
Abstract Plastic compositions based on polyvinylchloride, polyvinyldichloride, polyvinylidene chloride and their copolymers available in the form of scrap may be processed by solution techniques to yield a flexible, semi-rigid, or rigid variation of the original composition practically irrespective of the degree of physical contamination of the original plastic composition. The entire composition in the form as available in the original heavily contaminated scrap is recovered in pure form without such contamination by treating the scrap with a polar aprotic solvent, separating the contaminants from the solution by screen filtration, precipitating the desired ingredients of the plastic composition by flushing the polar aprotic solution of the polymer with water, separating all of the polar aprotic solvent dissolved in water by a combination of squeezing and vacuum evaporation, and finally separately recovering the water used for flushing and the polar aprotic solvent in substantially water-free form by distillation. The polar aprotic solvent utilized for placing the plastic in solution must be one which does not form an azeotropic mixture with water. In order to produce rigid varieties of these types of plastic compositions, the same general procedure is utilized, except that the liquid used for precipitation of the plastic dissolved in the polar aprotic solvent is selected from aliphatic alcohols, aliphatic straight chain saturated hydrocarbons, saturated hydrocarbons such as kerosene and turpentine, cyclic saturated hydrocarbons and glycols.
Inventors
- 👤 Eugene Wainer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:49
CPC Classifications
C; C08; C08J; C08J11/00; C08J11/04; C08J11/06; C08J11/08; C08J2327/00; C08J2327/02; C08J2327/04; C08J2327/06; Y; Y02; Y02P; Y02P20/00; Y02P20/50; Y02P20/582; Y02W; Y02W30/00; Y02W30/50; Y02W30/62
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
201 words
A PROCESS FOR THE RECOVERY OF A REUSABLE POLYVINYLCHLORIDE BASE COMPOSITION FROM SCAP MATERIAL CONSISTING OF THE CONSTITUENTS TO BE REFUSED AND CONTAMINANTS ASSOCIATED THEREWITH, WHICH PROCESS COMPRISES: COMUNUTING THE SCRAP MATERIAL INTO SMALL PIECES, DIGESTING THE SMALL PIECES OF SCRAP IN A POLAR APROTIC SOLVENT FOR ANY POLYVINYCHLORIDE POLYMER AND COPOLYMER IN SAID SCRAP, FOR A TIME SUFFICIENT TO EFFECT COMPLETE DISSOLUTION OF THE POLYVINYLCHLORIDE POLYMER AND COPOLYMER CONTENT OF SAID SCRAP, FILTERING THE RESULTING MIXTURE AND SEPARATELY RECOVERING A LIQUID FILTRATE CONTAINING THE POLYMER CONTENT, IN SOLUTION, AND A SOLID RESIDUE CONTAINING CONSTITUTENTS OF SAID SCRAP MATERIAL WHICH DID NOT DISSOLVE IN SAID POLAR APROTIC SOLVENT, THEN PRECIPITATING THE POLYMER FROM SOLUTION IN SAID FILTRATE BY FLUSHING SAID POLYMER FROM SAID SOLUTION IN SAID FILTRATE BY ADDITION OF A FLUSHING LIQUID SELECTED FROM THE GROUP CONSISTING OF WATER, SATURATED HYDROCARBONS HAVING BOILING POINTS AT LEAST 50*C LESS THAN THE BOILING POINT OF SAID POLAR APROTIC SOLVENT AND WHICH DOES NOT FORM AN AZEOTROPE WITH SAID POLAR APROTIC SOLVENT AND MIXTURES CONSISTING OF SAID SATURATED HYDROCARBONS AND LOWER ALIPHATIC (C1 - C4) ALCOHOLS: AND RECOVERING THE PRECIPITATING SOLID POLYMER CONTAINING MATERIAL, SEPARATELY FROM THE LIQUID IN WHICH IT WAS PRECIPITATED.
Claim 2
Dependent Claim
201 words
A PROCESS FOR THE RECOVERY OF A REUSABLE POLYVINYLCHLORIDE BASE COMPOSITION FROM SCAP MATERIAL CONSISTING OF THE CONSTITUENTS TO BE REFUSED AND CONTAMINANTS ASSOCIATED THEREWITH, WHICH PROCESS COMPRISES: COMUNUTING THE SCRAP MATERIAL INTO SMALL PIECES, DIGESTING THE SMALL PIECES OF SCRAP IN A POLAR APROTIC SOLVENT FOR ANY POLYVINYCHLORIDE POLYMER AND COPOLYMER IN SAID SCRAP, FOR A TIME SUFFICIENT TO EFFECT COMPLETE DISSOLUTION OF THE POLYVINYLCHLORIDE POLYMER AND COPOLYMER CONTENT OF SAID SCRAP, FILTERING THE RESULTING MIXTURE AND SEPARATELY RECOVERING A LIQUID FILTRATE CONTAINING THE POLYMER CONTENT, IN SOLUTION, AND A SOLID RESIDUE CONTAINING CONSTITUTENTS OF SAID SCRAP MATERIAL WHICH DID NOT DISSOLVE IN SAID POLAR APROTIC SOLVENT, THEN PRECIPITATING THE POLYMER FROM SOLUTION IN SAID FILTRATE BY FLUSHING SAID POLYMER FROM SAID SOLUTION IN SAID FILTRATE BY ADDITION OF A FLUSHING LIQUID SELECTED FROM THE GROUP CONSISTING OF WATER, SATURATED HYDROCARBONS HAVING BOILING POINTS AT LEAST 50*C LESS THAN THE BOILING POINT OF SAID POLAR APROTIC SOLVENT AND WHICH DOES NOT FORM AN AZEOTROPE WITH SAID POLAR APROTIC SOLVENT AND MIXTURES CONSISTING OF SAID SATURATED HYDROCARBONS AND LOWER ALIPHATIC (C1 - C4) ALCOHOLS: AND RECOVERING THE PRECIPITATING SOLID POLYMER CONTAINING MATERIAL, SEPARATELY FROM THE LIQUID IN WHICH IT WAS PRECIPITATED.
Claim 3
Dependent Claim
50 words
The process of claim 1 including in addition the steps of squeezing the recovered precipitated solid material thereby expelling flushing liquid and polar solvent adhering to the precipitated polymer; and separately recovering the expelled liquid and the squeeze-dried polymer; and returning the expelled liquid to the process of claim 1.
Claim 4
Dependent Claim
27 words
The process of claim 2 including vacuum drying the squeese-dried polymer residue, which is obtained after expulsion of the flushing liquid and polar solvent from said residue.
Claim 5
Dependent Claim
27 words
The process of claim 1 wherein the scrap being processed consists primarily of polyvinylchloride, polyvinylidene chloride and copolymers based on said polymers and mixtures of said polymers.
Claim 6
Dependent Claim
68 words
The process of claim 1 wherein the flushing liquid is water and the process includes: collecting the mixture of water and polar aprotic solvent which is separated from the precipitated polymer containing solid material, at each of the stages of the process where such a separation is effected; and separating the water from the polar aprotic solvent by distillation for their separate return to the process of claim
Claim 7
Dependent Claim
102 words
The process of claim 1 wherein the flushing liquid comprises at least one saturated hydrocarbon having a boiling point at least 50*C below the boiling point of said polar aprotic solvent and not forming an azeotrope with said polar aprotic solvent; and the process includes: recovery of the mixture of the hydrocarbon and the polar aprotic solvent and the plasticizer which is separated for the precipitated polymer containing solid material; effecting a rough separation of a fraction containing the aprotic solvent from a fraction containing the hydrocarbon and plasticizer; distilling the recovered hydrocarbon-plasticizer fraction; and separately recovering the plasticizer and the hydrocarbon.
Claim 8
Dependent Claim
16 words
The process of claim 6 wherein said flushing liquid is applied to the scrap in increments.
Claim 9
Dependent Claim
32 words
The process of claim 6 wherein the separation of plasticizer from the mixture of plaSticizer, hydrocarbon and polar aprotic solvent is effected in a plurality of extractions with the hydrocarbon as extractant.
Claim 10
Dependent Claim
63 words
The process of claim 1 wherein the flushing liquid is a mixture of aliphatic alcohols and saturated hydrocarbons, wherein said alcohols are selected from the group consisting of methyl, ethyl, propyl and butyl alcohols and said hydrocarbons are selected from hydrocarbons having boiling points of at least 50*C below the boiling point of said polar aprotic solvent and not forming an azeotrope therewith.
Claim 11
Dependent Claim
18 words
The process of claim 9 wherein the flushing luquid comprises about one part alcohol to two parts hydrocarbon.
Claim 12
Dependent Claim
26 words
The process of claim 9 including in addition distilling the mixture of alcohol, hydrocarbon, polar aprotic solvent and plasticizer and separately recovering the alcohol and hydrocarbon.
Claim 13
Dependent Claim
74 words
The process of claim 9 wherein the mixture separated from the precipitated polymer containing solid is processed for separate recovery of the aprotic solvent, alcohol, hydrocarbon and plasticizer contained therein by distilling said mixture and recovering the alcohol and hydrocarbon as a distillate, suitable for return to the process as a flushing liquid; and the polar solvent and plasticizer as a pot liquor, and thereafter separating the plasticizer from the polar solvent by distillation.
Claim 14
Dependent Claim
69 words
The process of claim 9 wherein the mixture separated from the precipitated polymer containing solid is processed for separate recovery of the aprotic solvent, alcohol, hydrocarbon and plasticizer contained therein by distilling said mixture and recovering the alcohol as a distillate, and a mixture containing the hydrocarbon, plasticizer and polar aprotic solvent as a residue; and separating said solvent from the remaining constituents by extraction in a separatory funnel.
Claim 15
Dependent Claim
90 words
The process of claim 9 wherein the mixture separated from the precipitated polymer containing solid is processed for separate recovery of the aprotic solvent, alcohol, hydrocarbon and plasticizer contained therein by distilling said mixture and recovering the alcohol and hydrocarbon as a distillate, suitable for return to the process as a flushing liquid; and the polar solvent and plasticizer as a pot liquor and thereafter separating the plasticizer from the solvent by adding water to said pot liquor whereby the plasticizer is precipitated and recovered separately from the aprotic solvent.
Claim 16
Dependent Claim
26 words
The process of claim 1 wherein said polar aprotic solvent is selected from the group consisting of 1,1,2,2-tetraethylurea, e-caprolactam, hexamethyl phosphoric triamide, gamma-butyrolactone, dimethylsulfoxide, and sulfolane.
Claim 17
Dependent Claim
31 words
The process of claim 1 wherein the saturated hydrocarbons are selected from the group consisting of cyclohexane, cyclopentane, hexane, heptane, octane, lead-free aviation gasoline, low boiling point kerosene, turpentine and iso-octane.
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) | 1978-10-13 | 1979-04-14 | 1979-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-13 | 1983-04-14 | 1983-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-13 | 1987-04-14 | 1987-10-14 | $7700.00 | Window Closed / Lapsed |